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Sample records for ionics electrolytic regeneration process

  1. Impact of regeneration process on the crystalline structure and enzymatic hydrolysis of cellulose obtained from ionic liquid.

    PubMed

    Cao, Xuefei; Peng, Xinwen; Sun, Shaoni; Zhong, Linxin; Wang, Sha; Lu, Fachuang; Sun, Runcang

    2014-10-13

    The present study investigated the impact of regeneration process on the crystalline structure and enzymatic hydrolysis behaviors of microcrystalline cellulose (MCC) regenerated from ionic liquid 1-butyl-3-methylimidazolium chloride. The crystalline structures of these regenerated samples were analyzed by X-ray diffraction. Results suggested that almost amorphous cellulose was obtained by regenerating MCC in acetone (DRC-a), while partial cellulose II structure could be found in these regenerated samples from water and ethanol. Additionally, the enzymatic hydrolysis behaviors of MCC and its regenerated samples were comparatively studied. Results showed that above 90% of cellulose could be converted into glucose within 4h for DRC-a and regenerated cellulose without drying (WRC-w) as compared to that of MCC (9.7%). Therefore, the regeneration process could significantly influence the crystallinity and digestibility of cellulose.

  2. Lithium ion conducting ionic electrolytes

    DOEpatents

    Angell, C.A.; Xu, K.; Liu, C.

    1996-01-16

    A liquid, predominantly lithium-conducting, ionic electrolyte is described which has exceptionally high conductivity at temperatures of 100 C or lower, including room temperature. It comprises molten lithium salts or salt mixtures in which a small amount of an anionic polymer lithium salt is dissolved to stabilize the liquid against recrystallization. Further, a liquid ionic electrolyte which has been rubberized by addition of an extra proportion of anionic polymer, and which has good chemical and electrochemical stability, is described. This presents an attractive alternative to conventional salt-in-polymer electrolytes which are not cationic conductors. 4 figs.

  3. Lithium ion conducting ionic electrolytes

    DOEpatents

    Angell, C. Austen; Xu, Kang; Liu, Changle

    1996-01-01

    A liquid, predominantly lithium-conducting, ionic electrolyte is described which has exceptionally high conductivity at temperatures of 100.degree. C. or lower, including room temperature. It comprises molten lithium salts or salt mixtures in which a small amount of an anionic polymer lithium salt is dissolved to stabilize the liquid against recrystallization. Further, a liquid ionic electrolyte which has been rubberized by addition of an extra proportion of anionic polymer, and which has good chemical and electrochemical stability, is described. This presents an attractive alternative to conventional salt-in-polymer electrolytes which are not cationic conductors.

  4. Solid electrolyte oxygen regeneration system

    NASA Technical Reports Server (NTRS)

    Shumar, J. W.; See, G. G.; Schubert, F. H.; Powell, J. D.

    1976-01-01

    A program to design, develop, fabricate and assemble a one-man, self-contained, solid electrolyte oxygen regeneration system (SX-1) incorporating solid electrolyte electrolyzer drums was completed. The SX-1 is a preprototype engineering model designed to produce 0.952 kg (2.1 lb)/day of breathable oxygen (O2) from the electrolysis of metabolic carbon dioxide (CO2) and water vapor. The CO2 supply rate was established based on the metabolic CO2 generation rate for one man of 0.998 kg (2.2 lb)/day. The water supply rate (0.254 kg (0.56 lb)/day) was designed to be sufficient to make up the difference between the 0.952 kg (2.1 lb)/day O2 generation specification and the O2 available through CO2 electrolysis, 0.726 kg (1.6 lb)/day. The SX-1 was successfully designed, fabricated and assembled. Design verification tests (DVT) or the CO Disproportionators, H2 separators, control instrumentation, monitor instrumentation, water feed mechanism were successfully completed. The erratic occurrence of electrolyzer drum leakage prevented the completion of the CO2 electrolyzer module and water electrolyzer module DVT's and also prevented the performance of SX-1 integrated testing. Further development work is required to improve the solid electrolyte cell high temperature seals.

  5. Nonaqueous Electrolyte Systems Ionic Transport in Nonaqueous Media.

    DTIC Science & Technology

    ALUMINATES, *IONIC CURRENT), (*ELECTROLYTES, ALUMINA), (*SULFITES, ELECTROLYTES), SODIUM COMPOUNDS, ELECTRICAL CONDUCTIVITY, TRANSPORT PROPERTIES, SOLUTIONS(MIXTURES), PERCHLORATES, FLUOBORATES , LITHIUM COMPOUNDS, VISCOSITY

  6. Polymer--Ionic liquid Electrolytes for Electrochemical Capacitors

    NASA Astrophysics Data System (ADS)

    Ketabi, Sanaz

    Polymer electrolyte, comprised of ionic conductors, polymer matrix, and additives, is one of the key components that control the performance of solid flexible electrochemical capacitors (ECs). Ionic liquids (ILs) are highly promising ionic conductors for next generation polymer electrolytes due to their excellent electrochemical and thermal stability. Fluorinated ILs are the most commonly applied in polymer-IL electrolytes. Although possessing high conductivity, these ILs have low environmental favorability. The aim of this work was to develop environmentally benign polymer-ILs for both electrochemical double layer capacitors (EDLCs) and pseudocapacitors, and to provide insights into the influence of constituent materials on the ion conduction mechanism and the structural stability of the polymer-IL electrolytes. Solid polymer electrolytes composed of poly(ethylene oxide) (PEO) and 1-ethyl-3-methylimidazolium hydrogen sulfate (EMIHSO4) were investigated for ECs. The material system was optimized to achieve the two criteria for high performance polymer-ILs: high ionic conductivity and highly amorphous structure. Thermal and structural analyses revealed that EMIHSO4 acted as an ionic conductor and a plasticizer that substantially decreased the crystallinity of PEO. Two types of inorganic nanofillers were incorporated into these polymer electrolytes. The effects of SiO2 and TiO2 nanofillers on ionic conductivity, crystallinity, and dielectric properties of PEO-EMIHSO 4 were studied over a temperature range from -10 °C and 80 °C. Using an electrochemical capacitor model, impedance (complex capacitance) and dielectric analyses were performed to understand the ionic conduction process with and without fillers in both semi crystalline and amorphous states of the polymer electrolytes. Despite their different nanostructures, both SiO2 and TiO2 promoted an amorphous structure in PEO-EMIHSO 4 and increased the ionic conductivity 2-fold. While in the amorphous state, the

  7. Magnesium Battery Electrolytes in Ionic Liquids

    NASA Astrophysics Data System (ADS)

    Watkins, Tylan Strike

    A lack of adequate energy storage technologies is arguably the greatest hindrance to a modern sustainable energy infrastructure. Chemical energy storage, in the form of batteries, is an obvious solution to the problem. Unfortunately, today's state of the art battery technologies fail to meet the desired metrics for full scale electric grid and/or electric vehicle role out. Considerable effort from scientists and engineers has gone into the pursuit of battery chemistries theoretically capable of far outperforming leading technologies like Li-ion cells. For instance, an anode of the relatively abundant and cheap metal, magnesium, would boost the specific energy by over 4.6 times that of the current Li-ion anode (LiC6). The work presented here explores the compatibility of magnesium electrolytes in TFSI---based ionic liquids with a Mg anode (TFSI = bis(trifluoromethylsulfonyl)imide). Correlations are made between the Mg2+ speciation conditions in bulk solutions (as determined via Raman spectroscopy) and the corresponding electrochemical behavior of the electrolytes. It was found that by creating specific chelating conditions, with an appropriate Mg salt, the desired electrochemical behavior could be obtained, i.e. reversible electrodeposition and dissolution. Removal of TFSI -- contact ion pairs from the Mg2+ solvation shell was found to be essential for reversible electrodeposition. Ionic liquids with polyethylene glycol chains pendent from a parent pyrrolidinium cation were synthesized and used to create the necessary complexes with Mg 2+, from Mg(BH4)2, so that reversible electrodeposition from a purely ionic liquid medium was achieved. The following document discusses findings from several electrochemical experiments on magnesium electrolytes in ionic liquids. Explanations for the failure of many of these systems to produce reversible Mg electrodeposition are provided. The key characteristics of ionic liquid systems that are capable of achieving reversible Mg

  8. Ionic conduction in polymer composite electrolytes

    NASA Astrophysics Data System (ADS)

    Dam, Tapabrata; Tripathy, Satya N.; Paluch, M.; Jena, S.; Pradhan, D. K.

    2016-05-01

    Conductivity and structural relaxation has been explored from modulus and dielectric loss formalisms respectively for a series of polymer composite electrolytes with zirconia as filler. The temperature dependence of conductivity followed Vogel-Tamman-Fulcher (VTF) behavior, which suggested a close correlation between conductivity and the segmental relaxation process in polymer electrolytes. Vogel temperature (T0) plays significant role in ion conduction process in these kind of materials.

  9. Ionic liquids, electrolyte solutions including the ionic liquids, and energy storage devices including the ionic liquids

    SciTech Connect

    Gering, Kevin L.; Harrup, Mason K.; Rollins, Harry W.

    2015-12-08

    An ionic liquid including a phosphazene compound that has a plurality of phosphorus-nitrogen units and at least one pendant group bonded to each phosphorus atom of the plurality of phosphorus-nitrogen units. One pendant group of the at least one pendant group comprises a positively charged pendant group. Additional embodiments of ionic liquids are disclosed, as are electrolyte solutions and energy storage devices including the embodiments of the ionic liquid.

  10. Room-temperature ionic liquid battery electrolytes

    SciTech Connect

    Carlin, R.T.; Fuller, J.

    1997-12-01

    The room-temperature molten salts possess a number of unique properties that make them ideal battery electrolytes. In particular, they are nonflammable, nonvolatile, and chemically inert, and they display wide electrochemical windows, high inherent conductivities, and wide thermal operating ranges. Although the ionic liquids have excellent characteristics, the chemical and electrochemical properties of desirable battery electrode materials are not well understood in these electrolytes. The research has focused on rechargeable electrodes and has included work on metallic lithium and sodium anodes in buffered neutral chloroaluminate melts, graphite-intercalation electrodes in neutral chloroaluminate and non-chloroaluminate melts, and silane-imidazole polymeric cathodes in acidic chloroaluminate melts. This paper will provide an overview of the research in these areas.

  11. Ionic conductivity in crystalline polymer electrolytes.

    PubMed

    Gadjourova, Z; Andreev, Y G; Tunstall, D P; Bruce, P G

    2001-08-02

    Polymer electrolytes are the subject of intensive study, in part because of their potential use as the electrolyte in all-solid-state rechargeable lithium batteries. These materials are formed by dissolving a salt (for example LiI) in a solid host polymer such as poly(ethylene oxide) (refs 2, 3, 4, 5, 6), and may be prepared as both crystalline and amorphous phases. Conductivity in polymer electrolytes has long been viewed as confined to the amorphous phase above the glass transition temperature, Tg, where polymer chain motion creates a dynamic, disordered environment that plays a critical role in facilitating ion transport. Here we show that, in contrast to this prevailing view, ionic conductivity in the static, ordered environment of the crystalline phase can be greater than that in the equivalent amorphous material above Tg. Moreover, we demonstrate that ion transport in crystalline polymer electrolytes can be dominated by the cations, whereas both ions are generally mobile in the amorphous phase. Restriction of mobility to the lithium cation is advantageous for battery applications. The realization that order can promote ion transport in polymers is interesting in the context of electronically conducting polymers, where crystallinity favours electron transport.

  12. An imidazolium based ionic liquid electrolyte for lithium batteries

    NASA Astrophysics Data System (ADS)

    Kim, Jae-Kwang; Matic, Aleksandar; Ahn, Jou-Hyeon; Jacobsson, Per

    An electrolyte for lithium batteries based on the ionic liquid 3-methy-1-propylimidazolium bis(trifluoromethysulfony)imide (PMIMTFSI) complexed with lithium bis(trifluoromethysulfony)imide (LiTFSI) at a molar ratio of 1:1 has been investigated. The electrolyte shows a high ionic conductivity (∼1.2 × 10 -3 S cm -1) at room temperature. Over the whole investigated temperature range the ionic conductivity is more than one order of magnitude higher than for an analogue electrolyte based on N-butyl-N-methyl-pyrrolidinium bis(trifluoromethanesulfonyl)imide (Py 14TFSI) complexed with LiTFSI and used here as a benchmark. Raman results indicate furthermore that the degree of lithium coordinated TFSI is slightly lower in the electrolyte based on PMIMTFSI and thus that the Li + charge carriers should be higher than in electrolytes based on Py 14TFSI. An ionic liquid gel electrolyte membrane was obtained by soaking a fibrous fully interconnected membrane, made of electrospun P(VdF-HFP), in the electrolyte. The gel electrolyte was cycled in Li/ionic liquid polymer electrolyte/Li cells over 15 days and in Li/LiFePO 4 cells demonstrating good interfacial stability and highly stable discharge capacities with a retention of >96% after 50 cycles (∼146 mAh g -1).

  13. Ionic conductivity enhancement of polymer electrolytes with ceramic nanowire fillers.

    PubMed

    Liu, Wei; Liu, Nian; Sun, Jie; Hsu, Po-Chun; Li, Yuzhang; Lee, Hyun-Wook; Cui, Yi

    2015-04-08

    Solid-state electrolytes provide substantial improvements to safety and electrochemical stability in lithium-ion batteries when compared with conventional liquid electrolytes, which makes them a promising alternative technology for next-generation high-energy batteries. Currently, the low mobility of lithium ions in solid electrolytes limits their practical application. The ongoing research over the past few decades on dispersing of ceramic nanoparticles into polymer matrix has been proved effective to enhance ionic conductivity although it is challenging to form the efficiency networks of ionic conduction with nanoparticles. In this work, we first report that ceramic nanowire fillers can facilitate formation of such ionic conduction networks in polymer-based solid electrolyte to enhance its ionic conductivity by three orders of magnitude. Polyacrylonitrile-LiClO4 incorporated with 15 wt % Li0.33La0.557TiO3 nanowire composite electrolyte exhibits an unprecedented ionic conductivity of 2.4 × 10(-4) S cm(-1) at room temperature, which is attributed to the fast ion transport on the surfaces of ceramic nanowires acting as conductive network in the polymer matrix. In addition, the ceramic-nanowire filled composite polymer electrolyte shows an enlarged electrochemical stability window in comparison to the one without fillers. The discovery in the present work paves the way for the design of solid ion electrolytes with superior performance.

  14. Composite Electrolytes for Lithium Batteries: Ionic Liquids in APTES Crosslinked Polymers

    NASA Technical Reports Server (NTRS)

    Tigelaar, Dean M.; Meador, Mary Ann B.; Bennett, William R.

    2007-01-01

    Solvent free polymer electrolytes were made consisting of Li(+) and pyrrolidinium salts of trifluoromethanesulfonimide added to a series of hyperbranched poly(ethylene oxide)s (PEO). The polymers were connected by triazine linkages and crosslinked by a sol-gel process to provide mechanical strength. The connecting PEO groups were varied to help understand the effects of polymer structure on electrolyte conductivity in the presence of ionic liquids. Polymers were also made that contain poly(dimethylsiloxane) groups, which provide increased flexibility without interacting with lithium ions. When large amounts of ionic liquid are added, there is little dependence of conductivity on the polymer structure. However, when smaller amounts of ionic liquid are added, the inherent conductivity of the polymer becomes a factor. These electrolytes are more conductive than those made with high molecular weight PEO imbibed with ionic liquids at ambient temperatures, due to the amorphous nature of the polymer.

  15. Regenerating cellulose from ionic liquids for an accelerated enzymatic hydrolysis

    SciTech Connect

    Zhao, Hua; Jones, Cecil L; Baker, Gary A; Xia, Shuqian; Olubajo, Olarongbe; Person, Vernecia

    2009-01-01

    The efficient conversion of lignocellulosic materials into fuel ethanol has become a research priority in producing affordable and renewable energy. The pretreatment of lignocelluloses is known to be key to the fast enzymatic hydrolysis of cellulose. Recently, certain ionic liquids (ILs)were found capable of dissolving more than 10 wt% cellulose. Preliminary investigations [Dadi, A.P., Varanasi, S., Schall, C.A., 2006. Enhancement of cellulose saccharification kinetics using an ionic liquid pretreatment step. Biotechnol. Bioeng. 95, 904 910; Liu, L., Chen, H., 2006. Enzymatic hydrolysis of cellulose materials treated with ionic liquid [BMIM]Cl. Chin. Sci. Bull. 51, 2432 2436; Dadi, A.P., Schall, C.A., Varanasi, S., 2007. Mitigation of cellulose recalcitrance to enzymatic hydrolysis by ionic liquid pretreatment. Appl. Biochem. Biotechnol. 137 140, 407 421] suggest that celluloses regenerated from IL solutions are subject to faster saccharification than untreated substrates. These encouraging results offer the possibility of using ILs as alternative and nonvolatile solvents for cellulose pretreatment. However, these studies are limited to two chloride-based ILs: (a) 1-butyl-3-methylimidazolium chloride ([BMIM]Cl), which is a corrosive, toxic and extremely hygroscopic solid (m.p. 70 C), and (b) 1-allyl-3-methylimidazolium chloride ([AMIM]Cl), which is viscous and has a reactive side-chain. Therefore, more in-depth research involving other ILs is much needed to explore this promising pretreatment route. For this reason, we studied a number of chloride- and acetate-based ILs for cellulose regeneration, including several ILs newly developed in our laboratory. This will enable us to select inexpensive, efficient and environmentally benign solvents for processing cellulosic biomass. Our data confirm that all regenerated celluloses are less crystalline (58 75% lower) and more accessible to cellulase (>2 times) than untreated substrates. As a result, regenerated Avicel

  16. Analysis of the solid electrolyte interphase formed with an ionic liquid electrolyte for lithium-sulfur batteries

    NASA Astrophysics Data System (ADS)

    Xiong, Shizhao; Xie, Kai; Blomberg, Erik; Jacobsson, Per; Matic, Aleksandar

    2014-04-01

    We have investigated the formation of the solid electrolyte interphase (SEI) on lithium electrodes in the presence of an ionic liquid electrolyte with a particular focus on the influence of polysulfides present in the electrolyte on the SEI. The electrochemical performance of symmetric cells with lithium electrodes and electrolytes composed of N-Methyl-(n-butyl)pyrrolidinium bis(trifluoromethanesulfonyl)imide (PYR14-TFSI) and LiTFSI, with and without the addition of polysulfides, were analyzed as well as the chemical composition of the SEI, before and after cycling. The cycling behavior of the symmetrical cells shows that the SEI films are relatively stable in the ionic liquid electrolyte, also in the presence of polysulfides. However, the presence of polysulfides results in a higher SEI layer resistance (RSEI) and a higher activation energy. From X-ray photoelectron spectroscopy spectra (XPS), with argon-ion sputtering for depth profiling, we find that the SEI is formed by decomposition products from both cations and anions of the electrolyte. The XPS spectra show that the presence of polysulfides alters the decomposition process of the electrolyte, resulting in a SEI film with different chemical composition and structure, in line with the results from the electrochemical performance.

  17. Structure, morphology and ionic conductivity of solid polymer electrolyte

    SciTech Connect

    Dey, Arup; Karan, S.; Dey, Ashis; De, S.K.

    2011-11-15

    Graphical abstract: Two-dimensional atomic force image of pure polyethylene oxide presents a crystallized network of regular spherulites developing spirals and branches of well distributed surface contours. Highlights: {yields} The incorporation of ceria significantly modifies the morphology of polyethylene oxide (PEO)-KI complex. {yields} The ionic conductivity increases by about two orders of magnitude by the addition of ceria nanoparticles. {yields} Ionic conductivity as a function of ceria concentration reveals two maxima. {yields} Grain boundary effect of nanofiller, strong Lewis acid-base interaction between PEO and nanosized ceria, change of conformation of PEO molecule and epitaxial effect of ceria nanoparticles control the ionic conductivity of composite polymer electrolyte. -- Abstract: Polyethylene oxide (PEO) complexed with potassium iodide (KI) is synthesized to investigate the ionic conductivity of alkaline based polymer electrolytes. The structural and morphological characterizations of the nanocomposite polymer electrolytes are performed by X-ray diffractometry (XRD), atomic force microscopy (AFM), differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR) measurements. The ionic conductivity increases with the increase of KI concentration up to about 20 wt.%. The effect of nanosized ceria (CeO{sub 2} {approx} 10 nm) fillers on ionic conductivity in PEO-KI polymer electrolyte is also carried out, keeping PEO to KI wt.% ratio 80:20 and 85:15. The result reveals that the addition of ceria nanoparticles enhances the conductivity by two orders of magnitude. The presence of ceria at the highest concentration induces the same molecular environment within PEO chain as that of undoped PEO. Temperature dependence of ionic conductivity follows Arrhenius mechanism.

  18. Engineering the Electrode-Electrolyte Interface: From Electrode Architecture to Zinc Redox in Ionic Liquid Electrolytes

    NASA Astrophysics Data System (ADS)

    Engstrom, Erika

    2011-12-01

    The electrode-electrolyte interface in electrochemical environments involves the understanding of complex processes relevant for all electrochemical applications. Some of these processes include electronic structure, charge storage, charge transfer, solvent dynamics and structure and surface adsorption. In order to engineer electrochemical systems, no matter the function, requires fundamental intuition of all the processes at the interface. The following work presents different systems in which the electrode-electrolyte interface is highly important. The first is a charge storage electrode utilizing percolation theory to develop an electrode architecture producing high capacities. This is followed by Zn deposition in an ionic liquid in which the deposition morphology is highly dependant on the charge transfer and surface adsorption at the interface. Electrode Architecture: A three-dimensional manganese oxide supercapacitor electrode architecture is synthesized by leveraging percolation theory to develop a hierarchically designed tri-continuous percolated network. The three percolated phases include a faradaically-active material, electrically conductive material and pore-former templated void space. The micropores create pathways for ionic conductivity, while the nanoscale electrically conducting phase provides both bulk conductivity and local electron transfer with the electrochemically active phase. Zn Electrodeposition: Zn redox in air and water stable N-ethyl-N-methylmorpholinium bis(trifluoromethanesulfonyl)imide, [C2nmm][NTf2] is presented. Under various conditions, characterization of overpotential, kinetics and diffusion of Zn species and morphological evolution as a function of overpotential and Zn concentration are analyzed. The surface stress evolution during Zn deposition is examined where grain size and texturing play significant rolls in compressive stress generation. Morphological repeatability in the ILs led to a novel study of purity in ionic

  19. Destabilization Mechanism of Ionic Surfactant on Curcumin Nanocrystal against Electrolytes.

    PubMed

    Rachmawati, Heni; Rahma, Annisa; Al Shaal, Loaye; Müller, Rainer H; Keck, Cornelia M

    2016-10-18

    We have successfully developed curcumin nanosuspension intended for oral delivery. The main purpose is to improve bioavailability through enhancing its solubility. The nanoparticles were stabilized using various stabilizers, including polyvinyl pyrrolidone (PVP), polyvinyl alcohol (PVA), sodium carboxymethylcellulose (Na-CMC), d-α-tocopheryl polyethylene glycol 1000 succinate (TPGS), and sodium dodecyl sulfate (SDS). The average diameter of particles, microscopic appearance, and sedimentation of each preparation was observed and compared. Each stabilizer demonstrated a different degree of inhibition of particle aggregation under electrolyte-containing simulated gastrointestinal (GIT) fluid. Non-ionic stabilizers (PVA, PVP, and TPGS) were shown to preserve the nanosuspension stability against electrolytes. In contrast, strong ionic surfactants such as SDS were found to be very sensitive to electrolytes. The results can provide useful information for the formulators to choose the most suitable stabilizers by considering the nature of stabilizers and physiological characteristics of the target site of the drug.

  20. Destabilization Mechanism of Ionic Surfactant on Curcumin Nanocrystal against Electrolytes

    PubMed Central

    Rachmawati, Heni; Rahma, Annisa; Al Shaal, Loaye; Müller, Rainer H.; Keck, Cornelia M.

    2016-01-01

    We have successfully developed curcumin nanosuspension intended for oral delivery. The main purpose is to improve bioavailability through enhancing its solubility. The nanoparticles were stabilized using various stabilizers, including polyvinyl pyrrolidone (PVP), polyvinyl alcohol (PVA), sodium carboxymethylcellulose (Na-CMC), d-α-tocopheryl polyethylene glycol 1000 succinate (TPGS), and sodium dodecyl sulfate (SDS). The average diameter of particles, microscopic appearance, and sedimentation of each preparation was observed and compared. Each stabilizer demonstrated a different degree of inhibition of particle aggregation under electrolyte-containing simulated gastrointestinal (GIT) fluid. Non-ionic stabilizers (PVA, PVP, and TPGS) were shown to preserve the nanosuspension stability against electrolytes. In contrast, strong ionic surfactants such as SDS were found to be very sensitive to electrolytes. The results can provide useful information for the formulators to choose the most suitable stabilizers by considering the nature of stabilizers and physiological characteristics of the target site of the drug. PMID:27763572

  1. Enhanced performance of dicationic ionic liquid electrolytes by organic solvents

    NASA Astrophysics Data System (ADS)

    Li, Song; Zhang, Pengfei; Fulvio Pasquale, F.; Hillesheim Patrick, C.; Feng, Guang; Dai, Sheng; Cummings Peter, T.

    2014-07-01

    The use of dicationic ionic liquid (DIL) electrolytes in supercapacitors is impeded by the slow dynamics of DILs, whereas the addition of organic solvents into DIL electrolytes improves ion transport and then enhances the power density of supercapacitors. In this work, the influences of organic solvents on the conductivity of DILs and the electrical double layer (EDL) of DIL-based supercapacitors are investigated using classical molecular dynamics simulation. Two types of organic solvents, acetonitrile (ACN) and propylene carbonate (PC), were used to explore the effects of different organic solvents on the EDL structure and capacitance of DIL/organic solvent-based supercapacitors. Firstly, it was found that the conductivity of DIL electrolytes was greatly enhanced in the presence of the organic solvent ACN. Secondly, a stronger adsorption of PC on graphite results in different EDL structures formed by DIL/ACN and DIL/PC electrolytes. The expulsion of co-ions from EDLs was observed in DIL/organic solvent electrolytes rather than neat DILs and this feature is more evident in DIL/PC. Furthermore, the bell-shaped differential capacitance-electric potential curve was not essentially changed by the presence of organic solvents. Comparing DIL/organic solvent electrolytes with neat DILs, the capacitance is slightly increased by organic solvents, which is in agreement with experimental observation.

  2. Printed environmentally friendly supercapacitors with ionic liquid electrolytes on paper

    NASA Astrophysics Data System (ADS)

    Pettersson, F.; Keskinen, J.; Remonen, T.; von Hertzen, L.; Jansson, E.; Tappura, K.; Zhang, Y.; Wilén, C.-E.; Österbacka, R.

    2014-12-01

    Environmentally friendly supercapacitors are fabricated using commercial grade aluminum coated paper as a substrate and symmetrical activated carbon electrodes as large area electrodes. Different choline chloride-based eutectic solvents are used as electrolyte. These are inexpensive, environmentally friendly and have a larger operating window compared to that of water electrolytes. As the entire device is printed and the materials used are inexpensive, both small- and large-area power sources can be fabricated to be used in cheap, disposable and recyclable devices. Supercapacitors with different eutectic solvents are measured using cyclic charge-discharge and impedance spectroscopy measurements and compared to one widely used and one "green" imidazolium ionic liquid; EMIM:TFSI and EcoEng 212™, respectively. A mixture of ethylene glycol and choline chloride, Glyceline™, show the highest capacitance and power densities of the electrolytes being tested, including the imidazolium alternatives.

  3. Silicon microhole arrays architecture for stable and efficient photoelectrochemical cells using ionic liquids electrolytes

    NASA Astrophysics Data System (ADS)

    Shen, Xiaojuan; Chen, Ling; Li, Junnan; Zhao, Jie

    2016-06-01

    Silicon microhole arrays (SiMHs) structure is constructed and fabricated by a low-cost maskless anodic etching process, which is applied as the photoanode for the silicon photoelectrochemical (PEC) cells. The depths of silicon microhole arrays can be independently controlled by the etching time. The light-scattering properties are also investigated. Additionally, surface morphology analysis show that large hole diameters of SiMHs is very favourable for the full-filling of ionic liquids electrolyte. Therefore, better electrochemical contact as well as high ionic conductivity of the ionic liquids electrolyte renders the PEC SiMHs solar cells to exhibit more excellent performance. After optimization, the maximum PCE could be achieved at 4.04% for the SiMHs cell. The performance of the SiMHs cell is highly comparable to that of silicon nanowires cell. More importantly, the liquid-state electrolyte is confined in the unique microhole structure, which can obviously prevent the leakage of the ionic liquids electrolyte, resulting in much better long-term stability than the reference devices. These preliminary results validate the concept of interpenetrating networks with semiconductor structure/ILs junction to develop stable and efficient PEC cells.

  4. Flexible thin-film battery based on solid-like ionic liquid-polymer electrolyte

    NASA Astrophysics Data System (ADS)

    Li, Qin; Ardebili, Haleh

    2016-01-01

    The development of high-performance flexible batteries is imperative for several contemporary applications including flexible electronics, wearable sensors and implantable medical devices. However, traditional organic liquid-based electrolytes are not ideal for flexible batteries due to their inherent safety and stability issues. In this study, a non-volatile, non-flammable and safe ionic liquid (IL)-based polymer electrolyte film with solid-like feature is fabricated and incorporated in a flexible lithium ion battery. The ionic liquid is 1-Ethyl-3-methylimidazolium dicyanamide (EMIMDCA) and the polymer is composed of poly(vinylidene fluoride-co-hexafluoropropene) (PVDF-HFP). The electrolyte exhibits good thermal stability (i.e. no weight loss up to 300 °C) and relatively high ionic conductivity (6 × 10-4 S cm-1). The flexible thin-film lithium ion battery based on solid-like electrolyte film is encapsulated using a thermal-lamination process and demonstrates excellent electrochemical performance, in both flat and bent configurations.

  5. Mixed ionic liquid as electrolyte for lithium batteries

    NASA Astrophysics Data System (ADS)

    Diaw, M.; Chagnes, A.; Carré, B.; Willmann, P.; Lemordant, D.

    Ionic liquids like 1-butyl-3-methylimidazolium tetrafluoroborate (IMIBF 4) or hexafluorophosphate (IMIPF 6) and 1-butyl-4-methylpyridinium tetrafluoroborate (PyBF 4) were mixed with organic solvents such as butyrolactone (BL) and acetonitrile (ACN). A lithium salt (LiBF 4 or LiPF 6) was added to these mixtures for possible application in the field of energy storage (batteries or supercapacitors). Viscosities, conductivities and electrochemical windows at a Pt electrode of these electrolytes were investigated. All studied electrolytes are stable toward oxidation and exhibit a vitreous phase transition, which has been determined by application of the VTF theory to conductivity measurements. Mixtures containing the BF 4- anion exhibit the lowest viscosity and the highest conductivity. Two mixtures have been optimized in terms of conductivity: BL/IMIBF 4 (60/40, v/v) and ACN/IMIBF 4 (70/30, v/v).

  6. Ionic liquid electrolytes as a platform for rechargeable metal-air batteries: a perspective.

    PubMed

    Kar, Mega; Simons, Tristan J; Forsyth, Maria; MacFarlane, Douglas R

    2014-09-21

    Metal-air batteries are a well-established technology that can offer high energy densities, low cost and environmental responsibility. Despite these favourable characteristics and utilisation of oxygen as the cathode reactant, these devices have been limited to primary applications, due to a number of problems that occur when the cell is recharged, including electrolyte loss and poor efficiency. Overcoming these obstacles is essential to creating a rechargeable metal-air battery that can be utilised for efficiently capturing renewable energy. Despite the first metal-air battery being created over 100 years ago, the emergence of reactive metals such as lithium has reinvigorated interest in this field. However the reactivity of some of these metals has generated a number of different philosophies regarding the electrolyte of the metal-air battery. Whilst much is already known about the anode and cathode processes in aqueous and organic electrolytes, the shortcomings of these electrolytes (i.e. volatility, instability, flammability etc.) have led some of the metal-air battery community to study room temperature ionic liquids (RTILs) as non-volatile, highly stable electrolytes that have the potential to support rechargeable metal-air battery processes. In this perspective, we discuss how some of these initial studies have demonstrated the capabilities of RTILs as metal-air battery electrolytes. We will also show that much of the long-held mechanistic knowledge of the oxygen electrode processes might not be applicable in RTIL based electrolytes, allowing for creative new solutions to the traditional irreversibility of the oxygen reduction reaction. Our understanding of key factors such as the effect of catalyst chemistry and surface structure, proton activity and interfacial reactions is still in its infancy in these novel electrolytes. In this perspective we highlight the key areas that need the attention of electrochemists and battery engineers, in order to progress

  7. Atomistic Simulations of Ternary Polymer Electrolytes Containing Ionic Liquids: Ion Transport and Viscoelastic Behavior

    NASA Astrophysics Data System (ADS)

    Mogurampelly, Santosh; Ganesan, Venkat

    Influence of the BMIMPF6 ionic liquid on ion transport and viscoelastic properties of ternary polymer electrolytes containing polyethylene oxide solvated with LiPF6 salt and the underlying mechanisms are investigated. By employing atomistic molecular dynamics and trajectory extended kinetic Monte Carlo simulation techniques, we observe enhanced ionic mobilities and conductivities of the PEOLiPF6-BMIMPF ternary electrolytes upon the addition ionic liquid into the PEOLiPF6 binary electrolyte. The dispersion of the BMIMPF6 ionic liquid into the PEOLiPF6 electrolyte is found to (a) promote dissociation of existing LiPF6 ion-pairs and (b) slightly accelerate the polymer segmental dynamics. Together, these effects are observed to collectively give rise to an increase in ionic mobilities and conductivities of the ternary polymer electrolyte. On the other hand, Rouse analysis reveals that the storage and loss modulus of the ternary polymer electrolytes are coupled to their ion conducting properties.

  8. Solid electrolyte material manufacturable by polymer processing methods

    DOEpatents

    Singh, Mohit; Gur, Ilan; Eitouni, Hany Basam; Balsara, Nitash Pervez

    2012-09-18

    The present invention relates generally to electrolyte materials. According to an embodiment, the present invention provides for a solid polymer electrolyte material that is ionically conductive, mechanically robust, and can be formed into desirable shapes using conventional polymer processing methods. An exemplary polymer electrolyte material has an elastic modulus in excess of 1.times.10.sup.6 Pa at 90 degrees C. and is characterized by an ionic conductivity of at least 1.times.10.sup.-5 Scm-1 at 90 degrees C. An exemplary material can be characterized by a two domain or three domain material system. An exemplary material can include material components made of diblock polymers or triblock polymers. Many uses are contemplated for the solid polymer electrolyte materials. For example, the present invention can be applied to improve Li-based batteries by means of enabling higher energy density, better thermal and environmental stability, lower rates of self-discharge, enhanced safety, lower manufacturing costs, and novel form factors.

  9. Frequency dependence of ionic conductivity of electrolyte solutions

    NASA Astrophysics Data System (ADS)

    Chandra, Amalendu; Bagchi, Biman

    2000-01-01

    A theory for the frequency dependence of ionic conductivity of an electrolyte solution is presented. In this theory contributions to the conductivity from both the ion atmosphere relaxation and the electrophoretic effects are included in a self-consistent fashion. Mode coupling theory, combined with time-dependent density functional theory of ion atmosphere fluctuations, leads to expressions for these two contributions at finite frequencies. These expressions need to be solved self-consistently for the frequency dependence of the electrolyte friction and the ion conductivity at varying ion concentrations. In the limit of low concentration, the present theory reduces exactly to the well-known Debye-Falkenhagen (DF) expression of the frequency-dependent electrolyte friction when the non-Markovian effects in the ion atmosphere relaxation are ignored and in addition the ions are considered to be pointlike. The present theory also reproduces the expressions of the frequency-dependent conductivity derived by Chandra, Wei, and Patey when appropriate limiting situations are considered. We have carried out detailed numerical solutions of the self-consistent equations for concentrated solutions of a 1:1 electrolyte by using the expressions of pair correlation functions given by Attard. Numerical results reveal that the frequency dependence of the electrolyte friction at finite concentration can be quite different from that given by the DF expression. With the increase of ion concentration, the dispersion of the friction is found to occur at a higher frequency because of faster relaxation of the ion atmosphere. At low frequency, the real part of the conductivity shows a small increase with frequency which can be attributed to the well-known Debye-Falkenhagen effect. At high frequency, the conductivity decreases as expected. The extensions of the present theory to treat frequency-dependent diffusivities of charged colloid suspensions and conductivity of a dilute

  10. Metal-air cell comprising an electrolyte with a room temperature ionic liquid and hygroscopic additive

    DOEpatents

    Friesen, Cody A.; Krishnan, Ramkumar; Tang, Toni; Wolfe, Derek

    2014-08-19

    An electrochemical cell comprising an electrolyte comprising water and a hydrophobic ionic liquid comprising positive ions and negative ions. The electrochemical cell also includes an air electrode configured to absorb and reduce oxygen. A hydrophilic or hygroscopic additive modulates the hydrophobicity of the ionic liquid to maintain a concentration of the water in the electrolyte is between 0.001 mol % and 25 mol %.

  11. The Effect of Ionic Strength on the Solubility of an Electrolyte

    ERIC Educational Resources Information Center

    Willey, Joan D.

    2004-01-01

    A simple experiment was conducted for studying and demonstrating visually and dramatically the effect of ionic strength on the solubility of an electrolyte is described. It is seen that the experiment visually illustrates the effect of ionic strength on electrolyte solubility by the appearance of the two solutions and by the difference in the…

  12. Study on Ion-Conducting Properties of Ionic Liquid Containing Carbonate Electrolytes Against Carbon Electrode.

    PubMed

    Choi, Bo-Ra; Park, Soo-Jin; Kim, Seok

    2016-03-01

    The ionic performances for the mixture of ethylene carbonate (EC) and dimethylcarbonate (DMC) were investigated for supercapacitor electrolyte. The usage of ethylene carbonate (EC) and dimethylcarbonate (DMC) as organic solvent could solve some problems of acetonitrile (AN). The general aim of present paper is compare to properties of electrochemical properties based on two mixed organic electrolytes. The ionic conductivity, viscosity, and electrochemical performances of EC/DMC+0.1 M TEABF4 mixtures were determined. The ionic conductivity of the electrolytes was measured by AC impedance, and the capacitative performances of the electrolytes were evaluated by using cyclic voltammetry.

  13. UV cross-linked, lithium-conducting ternary polymer electrolytes containing ionic liquids

    NASA Astrophysics Data System (ADS)

    Kim, G. T.; Appetecchi, G. B.; Carewska, M.; Joost, M.; Balducci, A.; Winter, M.; Passerini, S.

    In this manuscript is reported an attempt to prepare high ionic conductivity lithium polymer electrolytes by UV cross-linking the poly(ethyleneoxide) (briefly called PEO) polymer matrix in presence of the plasticizing lithium salt, lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and an ionic liquid of the pyrrolidinium family (N-alkyl- N-methylpyrrolidinium TFSI) having a common anion with the lithium salt. It is demonstrated that polymer electrolytes with room temperature ionic conductivities of nearly 10 -3 S cm -1 could be obtained as a result of the reduced crystallinity of the ternary electrolytes. The results clearly indicate that the cross-linked ternary electrolyte shows superior mechanical properties with respect to the non-cross-linked electrolytes and higher conductivities with respect to polymer electrolytes containing none or less ionic liquid.

  14. Passivation of Lithium Metal Anode via Hybrid Ionic Liquid Electrolyte toward Stable Li Plating/Stripping.

    PubMed

    Li, Nian-Wu; Yin, Ya-Xia; Li, Jin-Yi; Zhang, Chang-Huan; Guo, Yu-Guo

    2017-02-01

    Hybrid electrolyte of ionic liquid and ethers is used to passivate the surface of Li metal surface via modification of the as-formed solid electrolyte interphase with N-propyl-N-methylpyrrolidinium bis(trifluoromethanesulfonyl)amide (Py13TFSI), thereby reducing the side reactions between the Li metal and electrolyte, leading to remarkably suppressed Li dendrite growth and mitigating Li metal corrosion.

  15. Biopolymer Processing Using Ionic Liquids

    DTIC Science & Technology

    2014-08-07

    AFRL-OSR-VA-TR-2014-0181 (YIP-11) BIOPOLYMER PROCESSING USING IONIC LIQUIDS William Reichert UNIVERSITY OF SOUTH ALABAMA 08/07/2014 Final Report...3. DATES COVERED (From - To) May 2011-May 2014 4. TITLE AND SUBTITLE iopolymer Processing using Ionic Liquids for Feedstock Chemicals 5a...reaction and degradation products of the conversion of chitin and chitosan, and 3) investigate the effects of various reaction conditions, such as

  16. Separation of gases with solid electrolyte ionic conductors

    SciTech Connect

    Balachandran, U.; Dusek, J.T.; Maiya, P.S.; Mieville, R.L.; Ma, B.; Kleefisch, M.S.; Udovich, C.A.

    1996-11-01

    The authors have developed a novel method of gas separation based on electrolyte ionic membrane technology. Separation of one gas from another occurs through an ion-conducting membrane by the passage of selected ions. Most systems studied have focused on oxygen ion conduction for the separation of oxygen from air, although protonic and halide-conducting solid materials also exist. As an example of this system, this paper concentrates on a study of a membrane reactor used in the production of syngas (CO + H{sub 2}) from methane. The membrane material is a modified perovskite-type oxide exhibiting mixed (electronic/ionic) conductivity. Mixed-conductivity oxides are promising materials for oxygen-permeating membranes that can operate without electrodes or external electrical circuitry. Extruded tubes of this material have been evaluated in a reactor operating at {approx} 850 C for partial oxidation of methane into syngas in the presence of a reforming catalyst. Separated oxygen on one side of the reactor wall was obtained from air on the other side. Methane conversion efficiencies of > 99% were observed, and some of the reactor tubes have been operated for > 1,000 h. Membrane tubes were fabricated from calcined powders by a plastic extrusion technique. Characterization of the mechanical, physical, and chemical properties of this material confirmed the stability exhibited in the reactor.

  17. Li Ion Conducting Polymer Gel Electrolytes Based on Ionic Liquid/PVDF-HFP Blends

    PubMed Central

    Ye, Hui; Huang, Jian; Xu, Jun John; Khalfan, Amish; Greenbaum, Steve G.

    2009-01-01

    Ionic liquids thermodynamically compatible with Li metal are very promising for applications to rechargeable lithium batteries. 1-methyl-3-propylpyrrolidinium bis(trifluoromethanesulfonyl)imide (P13TFSI) is screened out as a particularly promising ionic liquid in this study. Dimensionally stable, elastic, flexible, nonvolatile polymer gel electrolytes (PGEs) with high electrochemical stabilities, high ionic conductivities and other desirable properties have been synthesized by dissolving Li imide salt (LiTFSI) in P13TFSI ionic liquid and then mixing the electrolyte solution with poly(vinylidene-co-hexafluoropropylene) (PVDF-HFP) copolymer. Adding small amounts of ethylene carbonate to the polymer gel electrolytes dramatically improves the ionic conductivity, net Li ion transport concentration, and Li ion transport kinetics of these electrolytes. They are thus favorable and offer good prospects in the application to rechargeable Li batteries including open systems like Li/air batteries, as well as more “conventional” rechargeable lithium and lithium ion batteries. PMID:20354587

  18. Crystalline, Glassy and Polymeric Electrolytes:. Similarities and Differences in Ionic Transport Mechanisms

    NASA Astrophysics Data System (ADS)

    Souquet, Jean Louis

    2006-06-01

    Ionocovalent crystals or glasses as well as molten salts or salt polymer complexes are currently studied as electrolytes for high energy density batteries. Their large Red/Ox stability range results from their thermodynamic or kinetic characteristics. For all these electrolytes, charge carriers are the consequence of local deviations from electroneutrality, identified as point defects for ionic crystals or partial dissociation in disordered structures. The charge carriers formation derives from a similar activated process. The main difference comes from the migration process, which depends on the dynamic properties of the surrounding medium. When the structural relaxation time is large, an activated process, mainly enthalpic, prevails for charge carriers migration. It is the usual case for ionic crystals or glasses. In the liquid or overcooled liquid states, the structural relaxation time of the medium is shorter that the time required for the activated migration process to occur and a local reorganization of the medium vanishes the energy barrier and provides the free volume necessary to ionic migration. In that case, the migration is mainly an entropic process. The configurational entropy necessary to this process decreases with temperature and vanishes at the so called ideal glass transition temperature which can be estimated by extrapolation of the transport properties or of the thermodynamic characteristics of the medium. However, at the experiment time scale, this configurational entropy disappears at a somewhat higher temperature, the glass transition temperature at which the structural relaxation time corresponds to the measurement time. Some glass forming ionic melts studied in a large temperature scale, over and below the glass transition temperature, evidence the two, enthalpic and entropic, migration mechanisms, allowing the determination of the thermodynamic characteristics of the charge carriers formation and migration. Some recent results indicate

  19. Morphology and Ionic Conductivity of Block Copolymer Electrolytes Containing Ionic Liquids

    NASA Astrophysics Data System (ADS)

    Park, Moon Jeong

    2015-03-01

    The global energy crisis and an increase in environmental pollution in the recent years have drawn the attention of the scientific community towards the development of efficient electrochemical devices. Polymers containing charged species have the potential to serve as electrolytes in next-generation devices and achieving high ion transport properties in these electrolytes is the key to improving their efficiency. Although the synthesis and characterization of a wide variety of ion-containing polymers have been extensively reported over the last decade, quantitative understanding of the factors governing the ion transport properties of these materials is in its infancy. In this talk, I will present the current understanding of the diverse factors affecting the thermodynamics, morphologies and ion transport of ion-containing polymers by focusing on the use of ionic liquids (ILs). Various strategies for accessing improved transport properties of IL-containing polymers are elucidated by focusing on the role of IL-polymer interactions. The major accomplishment of obtaining well-defined morphologies for these IL-containing polymers by the use of block copolymer is particularly emphasized as a novel means of controlling the transport properties. The application of IL-incorporated polymer electrolytes in high temperature fuel cells and electro-active actuators is also enclosed.

  20. Lithium insertion in graphite from ternary ionic liquid-lithium salt electrolytes. I. Electrochemical characterization of the electrolytes

    NASA Astrophysics Data System (ADS)

    Appetecchi, Giovanni B.; Montanino, Maria; Balducci, Andrea; Lux, Simon F.; Winterb, Martin; Passerini, Stefano

    In this paper we report the results of chemical-physical investigation performed on ternary room temperature ionic liquid-lithium salt mixtures as electrolytes for lithium-ion battery systems. The ternary electrolytes were made by mixing N-methyl- N-propyl pyrrolidinium bis(fluorosulfonyl) imide (PYR 13FSI) and N-butyl- N-methylpyrrolidinium bis(trifluoromethanesulfonyl) imide (PYR 14TFSI) ionic liquids with lithium hexafluorophosphate (LiPF 6) or lithium bis(trifluoromethanesulfonyl)imide (LiTFSI). The mixtures were developed based on preliminary results on the cyclability of graphite electrodes in the IL-LiX binary electrolytes. The results clearly show the beneficial synergic effect of the two ionic liquids on the electrochemical properties of the mixtures.

  1. Ionic Liquids as Electrolytes for Electrochemical Double-Layer Capacitors: Structures that Optimize Specific Energy.

    PubMed

    Mousavi, Maral P S; Wilson, Benjamin E; Kashefolgheta, Sadra; Anderson, Evan L; He, Siyao; Bühlmann, Philippe; Stein, Andreas

    2016-02-10

    Key parameters that influence the specific energy of electrochemical double-layer capacitors (EDLCs) are the double-layer capacitance and the operating potential of the cell. The operating potential of the cell is generally limited by the electrochemical window of the electrolyte solution, that is, the range of applied voltages within which the electrolyte or solvent is not reduced or oxidized. Ionic liquids are of interest as electrolytes for EDLCs because they offer relatively wide potential windows. Here, we provide a systematic study of the influence of the physical properties of ionic liquid electrolytes on the electrochemical stability and electrochemical performance (double-layer capacitance, specific energy) of EDLCs that employ a mesoporous carbon model electrode with uniform, highly interconnected mesopores (3DOm carbon). Several ionic liquids with structurally diverse anions (tetrafluoroborate, trifluoromethanesulfonate, trifluoromethanesulfonimide) and cations (imidazolium, ammonium, pyridinium, piperidinium, and pyrrolidinium) were investigated. We show that the cation size has a significant effect on the electrolyte viscosity and conductivity, as well as the capacitance of EDLCs. Imidazolium- and pyridinium-based ionic liquids provide the highest cell capacitance, and ammonium-based ionic liquids offer potential windows much larger than imidazolium and pyridinium ionic liquids. Increasing the chain length of the alkyl substituents in 1-alkyl-3-methylimidazolium trifluoromethanesulfonimide does not widen the potential window of the ionic liquid. We identified the ionic liquids that maximize the specific energies of EDLCs through the combined effects of their potential windows and the double-layer capacitance. The highest specific energies are obtained with ionic liquid electrolytes that possess moderate electrochemical stability, small ionic volumes, low viscosity, and hence high conductivity, the best performing ionic liquid tested being 1-ethyl-3

  2. Advances in the electrodeposition of aluminum from ionic liquid based electrolytes

    NASA Astrophysics Data System (ADS)

    Leadbetter, Kirt C.

    Aluminum plating is of considerable technical and economic interest because it provides an eco-friendly substitute for cadmium coatings used on many military systems. However, cadmium has been determined to be a significant environmental safety and occupational health (ESOH) hazard because of its toxicity and carcinogenic nature. Furthermore, the cost of treating and disposing of generated wastes, which often contain cyanide, is costly and is becoming prohibitive in the face of increasingly stringent regulatory standards. The non-toxic alternative aluminum is equivalent or superior in performance to cadmium. In addition, it could serve to provide an alternative to hexavalent chromium coatings used on military systems for similar reasons to that of cadmium. Aluminum is a beneficial alternative in that it demonstrates self-healing corrosion resistance in the form of a tightly-bound, impervious oxide layer. A successfully plated layer would be serviceable over a wider temperature range, 925 °F for aluminum compared to 450 oF for cadmium. In addition, an aluminum layer can be anodized to make it non-conducting and colorable. In consideration of the plating process, aluminum cannot be deposited from aqueous solutions because of its reduction potential. Therefore, nonaqueous electrolytes are required for deposition. Currently, aluminum can be electrodeposited in nonaqueous processes that use hazardous chemicals such as toluene and pyrophoric aluminum alkyls. Electrodeposition from ionic liquids provides the potential for a safer method that could be easily scaled up for industrial application. The plating process could be performed at a lower temperature and higher current density than other commercially available aluminum electrodeposition processes; thus a reduced process cost could be possible. The current ionic liquid based electrolytes are more expensive; however production on a larger scale and a long electrolyte lifetime are associated with a reduction in price

  3. An advanced lithium-air battery exploiting an ionic liquid-based electrolyte.

    PubMed

    Elia, G A; Hassoun, J; Kwak, W-J; Sun, Y-K; Scrosati, B; Mueller, F; Bresser, D; Passerini, S; Oberhumer, P; Tsiouvaras, N; Reiter, J

    2014-11-12

    A novel lithium-oxygen battery exploiting PYR14TFSI-LiTFSI as ionic liquid-based electrolyte medium is reported. The Li/PYR14TFSI-LiTFSI/O2 battery was fully characterized by electrochemical impedance spectroscopy, capacity-limited cycling, field emission scanning electron microscopy, high-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy. The results of this extensive study demonstrate that this new Li/O2 cell is characterized by a stable electrode-electrolyte interface and a highly reversible charge-discharge cycling behavior. Most remarkably, the charge process (oxygen oxidation reaction) is characterized by a very low overvoltage, enhancing the energy efficiency to 82%, thus, addressing one of the most critical issues preventing the practical application of lithium-oxygen batteries.

  4. Examination of the fundamental relation between ionic transport and segmental relaxation in polymer electrolytes

    SciTech Connect

    Wang, Yangyang; Fan, Fei; Agapov, Alexander L; Saito, Tomonori; Yang, Jun; Yu, Xiang; Hong, Kunlun; Mays, Jimmy; Sokolov, Alexei P

    2014-01-01

    Replacing traditional liquid electrolytes by polymers will significantly improve electrical energy storage technologies. Despite significant advantages for applications in electrochemical devices, the use of solid polymer electrolytes is strongly limited by their poor ionic conductivity. The classical theory predicts that the ionic transport is dictated by the segmental motion of the polymer matrix. As a result, the low mobility of polymer segments is often regarded as the limiting factor for development of polymers with sufficiently high ionic conductivity. Here, we show that the ionic conductivity in many polymers can be strongly decoupled from their segmental dynamics, in terms of both temperature dependence and relative transport rate. Based on this principle, we developed several polymers with superionic conductivity. The observed fast ion transport suggests a fundamental difference between the ionic transport mechanisms in polymers and small molecules and provides a new paradigm for design of highly conductive polymer electrolytes.

  5. Nonlinear ionic transport through microstructured solid electrolytes: homogenization estimates

    NASA Astrophysics Data System (ADS)

    Curto Sillamoni, Ignacio J.; Idiart, Martín I.

    2016-10-01

    We consider the transport of multiple ionic species by diffusion and migration through microstructured solid electrolytes in the presence of strong electric fields. The assumed constitutive relations for the constituent phases follow from convex energy and dissipation potentials which guarantee thermodynamic consistency. The effective response is heuristically deduced from a multi-scale convergence analysis of the relevant field equations. The resulting homogenized response involves an effective dissipation potential per species. Each potential is mathematically akin to that of a standard nonlinear heterogeneous conductor. A ‘linear-comparison’ homogenization technique is then used to generate estimates for these nonlinear potentials in terms of available estimates for corresponding linear conductors. By way of example, use is made of the Maxwell-Garnett and effective-medium linear approximations to generate estimates for two-phase systems with power-law dissipation. Explicit formulas are given for some limiting cases. In the case of threshold-type behavior, the estimates exhibit non-analytical dilute limits and seem to be consistent with fields localized in low energy paths.

  6. A disiloxane-functionalized phosphonium-based ionic liquid as electrolyte

    SciTech Connect

    Weng, Wei; Zhang, Zhengcheng; Lu, Jun; Amine, Khalil

    2011-01-01

    A disiloxane-functionalized ionic liquid based on a phosphonium cation and a bis(trifluoromethylsulfonyl)imide (TFSI) anion was synthesized and characterized. This new ionic liquid electrolyte showed good stability with a lithium transition metal oxide cathode and a graphite anode in lithium ion cells.

  7. Towards safer sodium-ion batteries via organic solvent/ionic liquid based hybrid electrolytes

    NASA Astrophysics Data System (ADS)

    Monti, Damien; Ponrouch, Alexandre; Palacín, M. Rosa; Johansson, Patrik

    2016-08-01

    Hybrid electrolytes aimed at application in sodium-ion batteries (SIB) consisting of an organic solvent mixture (EC:PC) and different ionic liquids (ILs); EMImTFSI, BMImTFSI, and Pyr13TFSI, and with the NaTFSI salt providing the Na+ charge carriers have here been extensively studied. The physico-chemical and electrochemical characterisation includes ionic conductivity, viscosity, density, cation coordination and solvation, various safety measures, and electrochemical stability window (ESW). Hybrid electrolytes with 10-50% of IL content were found to have ionic conductivities on par with comparable organic solvent based electrolytes, but with highly enhanced safety properties. A systematic Raman spectroscopy study of the cation coordination and solvation before and after electrolyte safety tests by ignition suggest that IL cations and TFSI remain stable when ignited while organic solvents are consumed. Finally, the solid electrolyte interphase (SEI) formed when using hybrid electrolytes has both better mechanical and electrochemical stability than the SEI derived from pure IL based electrolytes. For a half-cell with a hard carbon (HC) electrode and a hybrid electrolyte with a composition of 0.8 m NaTFSI in EC0.45:PC0.45:Pyr13TFSI0.10 encouraging results were obtained for IL based electrolytes - ca. 182 mAhg-1 at C/10 over 40 cycles.

  8. The Effect of Long Range Order on Ionic Conductivity in a Solid Block Copolymer Electrolyte

    NASA Astrophysics Data System (ADS)

    Chintapalli, Mahati; Thelen, Jacob; Teran, Alexander; Balsara, Nitash

    2014-03-01

    Poly(styrene)-block-poly(ethylene oxide) (SEO) mixed with lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) salt is a promising material for battery electrolytes due to its high ionic conductivity and ability to suppress lithium dendrite growth. Ion conduction has been found to depend on many aspects of the electrolyte microstructure, including the morphology and degree of ordering. The effect of long range order on ionic conductivity was investigated in a lamellar SEO/LiTFSI mixture by in situ small angle x-ray scattering and ac impedance spectroscopy during polymer annealing. The observation that increasing long range order decreases ionic conductivity indicates that disorder, due to small grain size or defects, enhances the ionic conductivity of the electrolyte.

  9. Electrolytic process for preparing uranium metal

    DOEpatents

    Haas, Paul A.

    1990-01-01

    An electrolytic process for making uranium from uranium oxide using Cl.sub.2 anode product from an electrolytic cell to react with UO.sub.2 to form uranium chlorides. The chlorides are used in low concentrations in a melt comprising fluorides and chlorides of potassium, sodium and barium in the electrolytic cell. The electrolysis produces Cl.sub.2 at the anode that reacts with UO.sub.2 in the feed reactor to form soluble UCl.sub.4, available for a continuous process in the electrolytic cell, rather than having insoluble UO.sub.2 fouling the cell.

  10. Optimization of Pore Structure of Cathodic Carbon Supports for Solvate Ionic Liquid Electrolytes Based Lithium-Sulfur Batteries.

    PubMed

    Zhang, Shiguo; Ikoma, Ai; Li, Zhe; Ueno, Kazuhide; Ma, Xiaofeng; Dokko, Kaoru; Watanabe, Masayoshi

    2016-10-04

    Lithium-sulfur (Li-S) batteries are a promising energy-storage technology owing to their high theoretical capacity and energy density. However, their practical application remains a challenge because of the serve shuttle effect caused by the dissolution of polysulfides in common organic electrolytes. Polysulfide-insoluble electrolytes, such as solvate ionic liquids (ILs), have recently emerged as alternative candidates and shown great potential in suppressing the shuttle effect and improving the cycle stability of Li-S batteries. Redox electrochemical reactions in polysulfide-insoluble electrolytes occur via a solid-state process at the interphase between the electrolyte and the composite cathode; therefore, creating an appropriate interface between sulfur and a carbon support is of great importance. Nevertheless, the porous carbon supports established for conventional organic electrolytes may not be suitable for polysulfide-insoluble electrolytes. In this work, we investigated the effect of the porous structure of carbon materials on the Li-S battery performance in polysulfide-insoluble electrolytes using solvate ILs as a model electrolyte. We determined that the pore volume (rather than the surface area) exerts a major influence on the discharge capacity of S composite cathodes. In particular, inverse opal carbons with three-dimensionally ordered interconnected macropores and a large pore volume deliver the highest discharge capacity. The battery performance in both polysulfide-soluble electrolytes and solvate ILs was used to study the effect of electrolytes. We propose a plausible mechanism to explain the different porous structure requirements in polysulfide-soluble and polysulfide-insoluble electrolytes.

  11. Ionogel Electrolytes through Sol-Gel Processing

    NASA Astrophysics Data System (ADS)

    Horowitz, Ariel I.

    Electrical energy needs have intensified due to the ubiquity of personal electronics, the decarbonization of energy services through electrification, and the use of intermittent renewable energy sources. Despite developments in mechanical and thermal methods, electrochemical technologies are the most convenient and effective means of storing electrical energy. These technologies include both electrochemical cells, commonly called batteries, and electrochemical double-layer capacitors, or "supercapacitors", which store energy electrostatically. Both device types require an ion-conducting electrolyte. Current devices use solutions of complex salts in organic solvents, leading to both toxicity and flammability concerns. These drawbacks can be avoided by replacing conventional electrolytes with room-temperature molten salts, known as ionic liquids (ILs). ILs are non-volatile, non-flammable, and offer high conductivity and good electrochemical stability. Device mass can be reduced by combining ILs with a solid scaffold material to form an "ionogel," further improving performance metrics. In this work, sol-gel chemistry is explored as a means of forming ionogel electrolytes. Sol-gel chemistry is a solution-based, industrially-relevant, well-studied technique by which solids such as silica can be formed in situ. Previous works used a simple acid-catalyzed sol-gel reaction to create brittle, glassy ionogels. Here, both the range of products that can be accomplished through sol-gel processing and the understanding of interactions between ILs and the sol-gel reaction network are greatly expanded. This work introduces novel ionogel materials, including soft and compliant silica-supported ionogels and PDMS-supported ionogels. The impacts of the reactive formulation, IL identity, and casting time are detailed. It is demonstrated that variations in formulation can lead to rapid gelation and open pore structures in the silica scaffold or slow gelation and more dense silica

  12. Enhanced electrical transport in ionic liquid dispersed TMAI-PEO solid polymer electrolyte

    SciTech Connect

    Gupta, Neha; Rathore, Munesh Dalvi, Anshuman; Kumar, Anil

    2014-04-24

    A polymer composite is prepared by dispersing ionic liquid [Bmim][BF{sub 4}] in Polyethylene oxide-tetra methyl ammonium iodide composite and subsequent microwave treatment. X-ray diffraction patterns confirm the composite nature. To explore possibility of proton conductivity in these films, electrical transport is studied by impedance spectroscopy and DC polarization. It is revealed that addition of ionic liquid in host TMAI-PEO solid polymer electrolyte enhances the conductivity by ∼ 2 orders of magnitude. Polarization measurements suggest that composites are essentially ion conducting in nature. The maximum ionic conductivity is found to be ∼2 × 10{sup −5} for 10 wt % ionic liquid.

  13. Capacitance of Ti3C2Tx MXene in ionic liquid electrolyte

    NASA Astrophysics Data System (ADS)

    Lin, Zifeng; Barbara, Daffos; Taberna, Pierre-Louis; Van Aken, Katherine L.; Anasori, Babak; Gogotsi, Yury; Simon, Patrice

    2016-09-01

    Ti3C2Tx MXene, a two-dimensional (2D) early transition metal carbide, has shown an extremely high volumetric capacitance in aqueous electrolytes, but in a narrow voltage window (less than 1.23 V). The utilization of MXene materials in ionic liquid electrolytes with a large voltage window has never been addressed. Here, we report the preparation of the Ti3C2Tx MXene ionogel film by vacuum filtration for use as supercapacitor electrodes operating in 1-Ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMI-TFSI) neat ionic liquid electrolyte. Due to the disordered structure of the Ti3C2Tx hydrogel film and a stable spacing after vacuum drying, achieved through ionic liquid electrolyte immersion of the Ti3C2Tx hydrogel film, the Ti3C2Tx surface became accessible to EMI+ and TFSI- ions. A capacitance of 70 F g-1 together with a large voltage window of 3 V was obtained at a scan rate of 20 mV s-1 in neat EMI-TFSI electrolyte. The electrochemical signature indicates a capacitive behavior even at a high scan rate (500 mV s-1) and a high power performance. This work opens up the possibilities of using MXene materials with various ionic liquid electrolytes.

  14. Capacitance of Ti3C2Tx MXene in Ionic Liquid Electrolyte

    DOE PAGES

    Lin, Zifeng; Barbara, Daffos; Taberna, Pierre-Louis; ...

    2016-04-14

    Ti3C2Tx MXene, a two-dimensional (2D) early transition metal carbide, has shown an extremely high volumetric capacitance in aqueous electrolytes, but in a narrow voltage window (less than 1.23 V). The utilization of MXene materials in ionic liquid electrolytes with a large voltage window has never been addressed. Here, we report the preparation of the Ti3C2Tx MXene ionogel film by vacuum filtration for use as supercapacitor electrodes operating in 1-Ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMI-TFSI) neat ionic liquid electrolyte. Due to the disordered structure of the Ti3C2Tx hydrogel film and a stable spacing after vacuum drying, achieved through ionic liquid electrolyte immersion of themore » Ti3C2Tx hydrogel film, the Ti3C2Tx surface became accessible to EMI+ and TFSI- ions. A capacitance of 70 F g-1 together with a large voltage window of 3 V was obtained at a scan rate of 20 mV s-1 in neat EMI-TFSI electrolyte. The electrochemical signature indicates a capacitive behavior even at a high scan rate (500 mV s-1) and a high power performance. This work opens up the possibilities of using MXene materials with various ionic liquid electrolytes.« less

  15. Ionic Transport Across Interfaces of Solid Glass and Polymer Electrolytes

    SciTech Connect

    Tenhaeff, Wyatt E; Yu, Xiang; Hong, Kunlun; Perry, Kelly A; Dudney, Nancy J

    2011-01-01

    A study of lithium cation transport across solid-solid electrolyte interfaces to identify critical resistances in nanostructured solid electrolytes is reported. Bilayers of glass and polymer thin film electrolytes were fabricated and characterized for this study. The glass electrolyte was lithium phosphorous oxynitride (Lipon), and two polymer electrolytes were studied: poly(methyl methacrylate-co-poly(ethylene glycol) methyl ether methacrylate) and poly(styrene-co-poly(ethylene glycol) methyl ether methacrylate). Both copolymers contained LiClO{sub 4} salt. In bilayers where polymer electrolyte layers are fabricated on top of Lipon, the interfacial resistance dominates transport. At 25 C, the interfacial resistance is at least three times greater than the sum of the Lipon and polymer electrolyte resistances. By reversing the structure and fabricating Lipon on top of the polymer electrolytes, the interfacial resistance is eliminated. Experiments to elucidate the origin of the interfacial resistance in the polymer-on-Lipon bilayers reveal that the solvent mixtures used to fabricate the polymer layers do not degrade the Lipon layer. The importance of the polymer electrolytes' mechanical properties is also discussed.

  16. Dissolution kinetics and mechanisms at dolomite-water interfaces: effects of electrolyte specific ionic strength.

    PubMed

    Xu, Man; Sullivan, Katie; Vanness, Garrett; Knauss, Kevin G; Higgins, Steven R

    2013-01-02

    Elucidating dissolution kinetics and mechanisms at carbonate mineral-water interfaces is essential to many environmental and geochemical processes, including geologic CO(2) sequestration in deep aquifers. In the present work, effects of background electrolytes on dolomite (CaMg(CO(3))(2)) reactivity were investigated by measuring step dissolution rates using in situ hydrothermal atomic force microscopy (HAFM) at 90 °C. Cleaved surfaces of dolomite were exposed to sodium chloride and tetramethylammonium chloride (TMACl) aqueous solutions with ionic strengths (I) ranging from 0 to 0.77 m at pH 4 and pH 9. HAFM results demonstrated that dolomite step retreat rates increased with increasing solution ionic strength and decreasing pH. Comparison of [481] and [441] steps revealed that the anisotropy of [481] and [441] step speeds became significant as solution ionic strength increased, with NaCl exerting more pronounced effects than TMACl for the same I. To interpret the different trends observed for NaCl and TMACl, a dissolution mechanism involving orientation-dependent ion adsorption and consequent edge free energy changes is proposed.

  17. Ionic liquid based lithium battery electrolytes: charge carriers and interactions derived by density functional theory calculations.

    PubMed

    Angenendt, Knut; Johansson, Patrik

    2011-06-23

    The solvation of lithium salts in ionic liquids (ILs) leads to the creation of a lithium ion carrying species quite different from those found in traditional nonaqueous lithium battery electrolytes. The most striking differences are that these species are composed only of ions and in general negatively charged. In many IL-based electrolytes, the dominant species are triplets, and the charge, stability, and size of the triplets have a large impact on the total ion conductivity, the lithium ion mobility, and also the lithium ion delivery at the electrode. As an inherent advantage, the triplets can be altered by selecting lithium salts and ionic liquids with different anions. Thus, within certain limits, the lithium ion carrying species can even be tailored toward distinct important properties for battery application. Here, we show by DFT calculations that the resulting charge carrying species from combinations of ionic liquids and lithium salts and also some resulting electrolyte properties can be predicted.

  18. Ionic-Liquid-Based Polymer Electrolytes for Battery Applications.

    PubMed

    Osada, Irene; de Vries, Henrik; Scrosati, Bruno; Passerini, Stefano

    2016-01-11

    The advent of solid-state polymer electrolytes for application in lithium batteries took place more than four decades ago when the ability of polyethylene oxide (PEO) to dissolve suitable lithium salts was demonstrated. Since then, many modifications of this basic system have been proposed and tested, involving the addition of conventional, carbonate-based electrolytes, low molecular weight polymers, ceramic fillers, and others. This Review focuses on ternary polymer electrolytes, that is, ion-conducting systems consisting of a polymer incorporating two salts, one bearing the lithium cation and the other introducing additional anions capable of plasticizing the polymer chains. Assessing the state of the research field of solid-state, ternary polymer electrolytes, while giving background on the whole field of polymer electrolytes, this Review is expected to stimulate new thoughts and ideas on the challenges and opportunities of lithium-metal batteries.

  19. Comparison of physical properties of regenerated cellulose films fabricated with different cellulose feedstocks in ionic liquid.

    PubMed

    Pang, JinHui; Wu, Miao; Zhang, QiaoHui; Tan, Xin; Xu, Feng; Zhang, XueMing; Sun, RunCang

    2015-05-05

    With the serious "white pollution" resulted from the non-biodegradable plastic films, considerable attention has been directed toward the development of renewable and biodegradable cellulose-based film materials as substitutes of petroleum-derived materials. In this study, environmentally friendly cellulose films were successfully prepared using different celluloses (pine, cotton, bamboo, MCC) as raw materials and ionic liquid 1-ethyl-3-methylimidazolium acetate as a solvent. The SEM and AFM indicated that all cellulose films displayed a homogeneous and smooth surface. In addition, the FT-IR and XRD analysis showed the transition from cellulose I to II was occurred after the dissolution and regeneration process. Furthermore, the cellulose films prepared by cotton linters and pine possessed the most excellent thermal stability and mechanical properties, which were suggested by the highest onset temperature (285°C) and tensile stress (120 MPa), respectively. Their excellent properties of regenerated cellulose films are promising for applications in food packaging and medical materials.

  20. Crosslinked polymer gel electrolytes based on polyethylene glycol methacrylate and ionic liquid for lithium battery applications

    SciTech Connect

    Liao, Chen; Sun, Xiao-Guang; Dai, Sheng

    2013-01-01

    Gel polymer electrolytes were synthesized by copolymerization polyethylene glycol methyl ether methacrylate with polyethylene glycol dimethacrylate in the presence of a room temperature ionic liquid, methylpropylpyrrolidinium bis(trifluoromethanesulfonyl)imide (MPPY TFSI). The physical properties of gel polymer electrolytes were characterized by thermal analysis, impedance spectroscopy, and electrochemical tests. The ionic conductivities of the gel polymer electrolytes increased linearly with the amount of MPPY TFSI and were mainly attributed to the increased ion mobility as evidenced by the decreased glass transition temperatures. Li||LiFePO4 cells were assembled using the gel polymer electrolytes containing 80 wt% MPPY TFSI via an in situ polymerization method. A reversible cell capacity of 90 mAh g 1 was maintained under the current density of C/10 at room temperature, which was increased to 130 mAh g 1 by using a thinner membrane and cycling at 50 C.

  1. Solid-state supercapacitors with ionic liquid based gel polymer electrolyte: Effect of lithium salt addition

    NASA Astrophysics Data System (ADS)

    Pandey, G. P.; Hashmi, S. A.

    2013-12-01

    Performance characteristics of the solid-state supercapacitors fabricated with ionic liquid (IL) incorporated gel polymer electrolyte and acid treated multiwalled carbon nanotube (MWCNT) electrodes have been studied. The effect of Li-salt (LiPF6) addition in the IL (1-ethyl-3-methylimidazolium tris(pentafluoroethyl) trifluorophosphate, EMImFAP) based gel electrolyte on the performance of supercapacitors has been specifically investigated. The LiPF6/IL/poly(vinylidine fluoride-co-hexafluoropropylene) (PVdF-HFP) gel electrolyte film possesses excellent electrochemical window of 4 V (from -2.0 to 2.0 V), high ionic conductivity ˜2.6 × 10-3 S cm-1 at 20 °C and high enough thermal stability. The comparative performance of supercapacitors employing electrolytes with and without lithium salt has been evaluated by impedance spectroscopy and cyclic voltammetric studies. The acid-treated MWCNT electrodes show specific capacitance of ˜127 F g-1 with IL/LiPF6 containing gel polymer electrolyte as compared to that with the gel polymer electrolyte without Li-salt, showing the value of ˜76 F g-1. The long cycling stability of the solid state supercapacitor based on the Li-salt containing gel polymer electrolyte confirms the electrochemical stability of the electrolyte.

  2. Determination of preservatives in soft drinks by capillary electrophoresis with ionic liquids as the electrolyte additives.

    PubMed

    Sun, Bingbing; Qi, Li; Wang, Minglin

    2014-08-01

    A capillary electrophoresis method for separating preservatives with various ionic liquids as the electrolyte additives has been developed. The performances for separation of the preservatives using five ionic liquids with different anions and different substituted group numbers on imidazole ring were studied. After investigating the influence of the key parameters on the separation (the concentration of ionic liquids, pH, and the concentration of borax), it has been found that the separation efficiency could be improved obviously using the ionic liquids as the electrolyte additives and tested preservatives were baseline separated. The proposed capillary electrophoresis method exhibited favorable quantitative analysis property of the preservatives with good linearity (r(2) = 0.998), repeatability (relative standard deviations ≤ 3.3%) and high recovery (79.4-117.5%). Furthermore, this feasible and efficient capillary electrophoresis method was applied in detecting the preservatives in soft drinks, introducing a new way for assaying the preservatives in food products.

  3. Higher energy and safety of lithium-ion batteries with ionic liquid electrolyte

    NASA Astrophysics Data System (ADS)

    Komaba, Shinichi; Yabuuchi, Naoaki; Katayama, Yasushi; Miura, Takashi

    2010-04-01

    Ionic liquid has been utilized as safe electrolyte solution for lithium-ion batteries. Reversible charge / discharge cycling of the graphite electrode in the ionic liquid has been achieved with polyacrylic acid polymer binder, which can suppress the organic cation intercalation to the graphite. Cycleability of the graphite-silicon composite electrodes prepared with polyacrylate binder was significantly improved in comparison to the conventional PVdF binder, and it has been demonstrated that the reversible cycling with 1000 mAh g-1 for 30 cycling test is possible in ionic liquid. The possibility of the safe and high-energy lithium-ion battery is discussed through the preliminary study on Li2MnO3-LiCo1/3Ni1/3Mn1/3O2 based positive electrode and graphite-silicon-polyacrylate composite negative electrode with the ionic liquid electrolyte.

  4. The Role of Dissolved Gas in Ionic Liquid Electrolytes for Secondary Lithium Metal Batteries

    DTIC Science & Technology

    2013-01-07

    devices use lithium - ion batteries comprised of a graphite anode and metal oxide cathode. Lithium , being the third-lightest element, is already synonymous...support shuttling lithium ions ( battery cycling) such as the separator, electrolyte, and cathode and anode superstructures contribute most of the...The Role of Dissolved Gas in Ionic Liquid Electrolytes for Secondary Lithium Metal Batteries Johanna K. Stark1, Yi Ding2, and Paul A. Kohl1

  5. Improved electrolytes for Li-ion batteries: Mixtures of ionic liquid and organic electrolyte with enhanced safety and electrochemical performance

    NASA Astrophysics Data System (ADS)

    Guerfi, A.; Dontigny, M.; Charest, P.; Petitclerc, M.; Lagacé, M.; Vijh, A.; Zaghib, K.

    Physical and electrochemical characteristics of Li-ion battery systems based on LiFePO 4 cathodes and graphite anodes with mixture electrolytes were investigated. The mixed electrolytes are based on an ionic liquid (IL), and organic solvents used in commercial batteries. We investigated a range of compositions to determine an optimum conductivity and non-flammability of the mixed electrolyte. This led us to examine mixtures of ILs with the organic electrolyte usually employed in commercial Li-ion batteries, i.e., ethylene carbonate (EC) and diethylene carbonate (DEC). The IL electrolyte consisted of (trifluoromethyl sulfonylimide) (TFSI) as anion and 1-ethyl-3-methyleimidazolium (EMI) as the cation. The physical and electrochemical properties of some of these mixtures showed an improvement characteristics compared to the constituents alone. The safety was improved with electrolyte mixtures; when IL content in the mixture is ≥40%, no flammability is observed. A stable SEI layer was obtained on the MCMB graphite anode in these mixed electrolytes, which is not obtained with IL containing the TFSI-anion. The high-rate capability of LiFePO 4 is similar in the organic electrolyte and the mixture with a composition of 1:1. The interface resistance of the LiFePO 4 cathode is stabilized when the IL is added to the electrolyte. A reversible capacity of 155 mAh g -1 at C/12 is obtained with cells having at least some organic electrolyte compared to only 124 mAh g -1 with pure IL. With increasing discharge rate, the capacity is maintained close to that in the organic solvent up to 2 C rate. At higher rates, the results with mixture electrolytes start to deviate from the pure organic electrolyte cell. The evaluation of the Li-ion cells; LiFePO 4//Li 4Ti 5O 12 with organic and, 40% mixture electrolytes showed good 1st CE at 98.7 and 93.0%, respectively. The power performance of both cell configurations is comparable up to 2 C rate. This study indicates that safety and

  6. Polymeric Ionic Networks with High Charge Density: Solid-like Electrolytes in Lithium Metal Batteries

    DOE PAGES

    Zhang, Pengfei; Li, Mingtao; Jiang, Xueguang; ...

    2015-11-02

    Polymerized ionic networks (PINs) with six ion pairs per repeating unit are synthesized by nucleophilic-substitution-mediated polymerization or radical polymerization of monomers bearing six 1-vinylimidazolium cations. PIN-based solid-like electrolytes show good ionic conductivities (up to 5.32 × 10-3 S cm-1 at 22 °C), wide electrochemical stability windows (up to 5.6 V), and good interfacial compatibility with the electrodes.

  7. Polymeric Ionic Networks with High Charge Density: Solid-like Electrolytes in Lithium Metal Batteries

    SciTech Connect

    Zhang, Pengfei; Li, Mingtao; Jiang, Xueguang; Fang, Youxing; Veith, Gabriel M.; Sun, Xiao-Guang; Dai, Sheng

    2015-11-02

    Polymerized ionic networks (PINs) with six ion pairs per repeating unit are synthesized by nucleophilic-substitution-mediated polymerization or radical polymerization of monomers bearing six 1-vinylimidazolium cations. PIN-based solid-like electrolytes show good ionic conductivities (up to 5.32 × 10-3 S cm-1 at 22 °C), wide electrochemical stability windows (up to 5.6 V), and good interfacial compatibility with the electrodes.

  8. Formulation of ionic liquid electrolyte to expand the voltage window of supercapacitors

    DOE PAGES

    Van Aken, Katherine L.; Beidaghi, Majid; Gogotsi, Yury

    2015-03-18

    We report an effective method to expand the operating potential window (OPW) of electrochemical capacitors based on formulating the ionic liquid (IL) electrolytes. Moreover, using model electrochemical cells based on two identical onion like carbon (OLC) electrodes and two different IL electrolytes and their mixtures, it was shown that the asymmetric behavior of the electrolyte’s cation and anion toward the two electrodes limits the OPW of the cell and therefore its energy density. Additionally, a general solution to this problem is proposed by formulating the IL electrolyte mixtures to balance the capacitance of electrodes in a symmetric supercapacitor.

  9. Electrochemical properties of the double layer of an ionic liquid using a dimer model electrolyte and density functional theory.

    PubMed

    Henderson, Douglas; Wu, Jianzhong

    2012-03-01

    Most theoretical studies of the properties of an electrolyte, including an ionic liquid, treat the electrolyte as a mixture of charged hard spheres in a solvent modeled as a dielectric continuum. However, ionic liquids generally consist of nonspherical ions that are not dissolved in a solvent. A simple extension of the primitivel model of electrolytes is to represent an ionic liquid as a mixture of charged hard spheres (negative monovalent ions in our case) and nonspherical ions consisting of a dimer of two touching hard spheres, one of which is charged (monovalent and positive in our case) and the other is neutral. This simple model has been used previously by Federov et al. and by ourselves. Here, we use the classical density functional theory to study the interfacial properties of the model ionic liquid over a range of electrode charges and two electrolyte concentrations. For simplicity, all of the spheres have the same diameter. In contrast to the simulations of Federov and Kornyshev, we find that a plot of the differential capacitance of the dimer electrolyte versus the surface potential typically exhibits only a single hump. Also, differing from the studies of Lamperski et al. for a spherical electrolyte, which showed a decline of the maximal differential capacitance as the ionic concentration decreases, the maximum of the differential capacitance of the dimer electrolyte increases slightly with decreasing ionic concentration. Our theoretical results show other unexpected effects of the geometry of ionic species on the electrochemical properties of the electric double layer of an ionic liquid.

  10. Investigation of Interface between Ge Electrodes and Ionic Liquid Electrolytes for Electric Double Layer Capacitors

    NASA Astrophysics Data System (ADS)

    Abeysinghe, R. M.; Oguchi, H.; Kuwano, H.

    2016-11-01

    This study discusses novel way of use of ionic liquids to develop Ge-based electrodes for electric double layer capacitors (EDLC). We found that ionic liquids change their electrochemical properties depending on the amount of the absorbed water. Wet ionic liquids work as solvents to dissolve Ge and make porous structures, whereas dry ones work as electrolytes of the EDLCs. The former property was used to increase surface area of the electrodes which is desired to increase the capacity of EDLCs. This method showed another advantage in contrast to the dry ionic liquids; wet ones could fill the complex Ge pores in parallel to porous structure formation. Finally, after porous formation, we dried the ionic liquid at 100 °C and prepared the EDLCs composed of Ge porous electrodes. Cyclic voltammetry and impedance measurements indicated that the obtained devices can work as EDLCs.

  11. Mesoscopic Framework Enables Facile Ionic Transport in Solid Electrolytes for Li Batteries

    SciTech Connect

    Ma, Cheng; Cheng, Yongqiang; Chen, Kai; Li, Juchuan; Sumpter, Bobby G.; Nan, Ce-Wen; More, Karren L.; Dudney, Nancy J.; Chi, Miaofang

    2016-03-29

    In Li-ion-conducting solid electrolytes can simultaneously overcome two grand challenges for Li-ion batteries: the severe safety concerns that limit the large-scale application and the poor electrolyte stability that forbids the use of high-voltage cathodes. Nevertheless, the ionic conductivity of solid electrolytes is typically low, compromising the battery performances. Precisely determining the ionic transport mechanism(s) is a prerequisite for the rational design of highly conductive solid electrolytes. For decades, the research on this subject has primarily focused on the atomic and microscopic scales, where the main features of interest are unit cells and microstructures, respectively. We show that the largely overlooked mesoscopic scale lying between these extremes could be the key to fast ionic conduction. In a prototype system, (Li0.33La0.56)TiO3, a mesoscopic framework is revealed for the first time by state-of-the-art scanning transmission electron microscopy. Corroborated by theoretical calculations and impedance measurements, it is demonstrated that such a unique configuration maximizes the number of percolation directions and thus most effectively improves the ionic conductivity. Finally, this discovery reconciles the long-standing structure–property inconsistency in (Li0.33La0.56)TiO3 and also identifies mesoscopic ordering as a promising general strategy for optimizing Li+ conduction.

  12. Mesoscopic Framework Enables Facile Ionic Transport in Solid Electrolytes for Li Batteries

    DOE PAGES

    Ma, Cheng; Cheng, Yongqiang; Chen, Kai; ...

    2016-03-29

    In Li-ion-conducting solid electrolytes can simultaneously overcome two grand challenges for Li-ion batteries: the severe safety concerns that limit the large-scale application and the poor electrolyte stability that forbids the use of high-voltage cathodes. Nevertheless, the ionic conductivity of solid electrolytes is typically low, compromising the battery performances. Precisely determining the ionic transport mechanism(s) is a prerequisite for the rational design of highly conductive solid electrolytes. For decades, the research on this subject has primarily focused on the atomic and microscopic scales, where the main features of interest are unit cells and microstructures, respectively. We show that the largely overlookedmore » mesoscopic scale lying between these extremes could be the key to fast ionic conduction. In a prototype system, (Li0.33La0.56)TiO3, a mesoscopic framework is revealed for the first time by state-of-the-art scanning transmission electron microscopy. Corroborated by theoretical calculations and impedance measurements, it is demonstrated that such a unique configuration maximizes the number of percolation directions and thus most effectively improves the ionic conductivity. Finally, this discovery reconciles the long-standing structure–property inconsistency in (Li0.33La0.56)TiO3 and also identifies mesoscopic ordering as a promising general strategy for optimizing Li+ conduction.« less

  13. Thermo- and electro-dual responsive poly(ionic liquid) electrolyte based smart windows.

    PubMed

    Chen, Fei; Ren, Yongyuan; Guo, Jiangna; Yan, Feng

    2017-01-31

    Thermo- and electro-dual responsive poly(ionic liquid) (PIL) based electrolytes were synthesized by co-polymerization of N-isopropylacrylamide (NIPAM) with (or without) 3-butyl-1-vinyl-imidazolium bromide ([BVIm][Br]) using diallyl-viologen (DAV) as both the cross-linking agent and electrochromic material.

  14. Eco-friendly Energy Storage System: Seawater and Ionic Liquid Electrolyte.

    PubMed

    Kim, Jae-Kwang; Mueller, Franziska; Kim, Hyojin; Jeong, Sangsik; Park, Jeong-Sun; Passerini, Stefano; Kim, Youngsik

    2016-01-08

    As existing battery technologies struggle to meet the requirements for widespread use in the field of large-scale energy storage, novel concepts are urgently needed concerning batteries that have high energy densities, low costs, and high levels of safety. Here, a novel eco-friendly energy storage system (ESS) using seawater and an ionic liquid is proposed for the first time; this represents an intermediate system between a battery and a fuel cell, and is accordingly referred to as a hybrid rechargeable cell. Compared to conventional organic electrolytes, the ionic liquid electrolyte significantly enhances the cycle performance of the seawater hybrid rechargeable system, acting as a very stable interface layer between the Sn-C (Na storage) anode and the NASICON (Na3 Zr2 Si2 PO12) ceramic solid electrolyte, making this system extremely promising for cost-efficient and environmentally friendly large-scale energy storage.

  15. Mixtures of protic ionic liquids and propylene carbonate as advanced electrolytes for lithium-ion batteries.

    PubMed

    Vogl, T; Menne, S; Balducci, A

    2014-12-07

    In this study we investigated the chemical-physical properties of mixtures containing the protic ionic liquid (PIL) N-butyl-pyrrolidinium bis(trifluoromethanesulfonyl)imide (PYRH4TFSI), propylene carbonate (PC) and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) in view of their use as electrolytes for lithium-ion batteries (LIBs). We showed that these electrolytic solutions might display conductivity and viscosity comparable to those of conventional electrolytes. Depending on the amount of PIL present inside the mixtures, such mixtures might also display the ability to suppress the anodic dissolution of Al. Furthermore, we showed that the coordination of lithium ions by TFSI in PIL-PC mixtures appears to be different than the one observed for mixtures of PC and aprotic ionic liquids (AILs). When used in combination with a battery electrode, e.g. lithium iron phosphate (LFP), these mixtures allow the achievement of high performance also at a very high C-rate.

  16. Ternary polymer electrolytes containing pyrrolidinium-based polymeric ionic liquids for lithium batteries

    NASA Astrophysics Data System (ADS)

    Appetecchi, G. B.; Kim, G.-T.; Montanino, M.; Carewska, M.; Marcilla, R.; Mecerreyes, D.; De Meatza, I.

    The electrochemical properties of solvent-free, ternary polymer electrolytes based on a novel poly(diallyldimethylammonium) bis(trifluoromethanesulfonyl)imide polymeric ionic liquid (PIL) as polymer host and incorporating PYR 14TFSI ionic liquid and LiTFSI salt are reported. The PIL-LiTFSI-PYR 14TFSI electrolyte membranes were found to be chemically stable even after prolonged storage times in contact with lithium anode and thermally stable up to 300 °C. Particularly, the PIL-based electrolytes exhibited acceptable room temperature conductivity with wide electrochemical stability window, time-stable interfacial resistance values and good lithium stripping/plating performance. Preliminary battery tests have shown that Li/LiFePO 4 solid-state cells are capable to deliver above 140 mAh g -1 at 40 °C with very good capacity retention up to medium rates.

  17. Enhanced anisotropic ionic diffusion in layered electrolyte structures from density functional theory

    NASA Astrophysics Data System (ADS)

    Hirschfeld, J. A.; Lustfeld, H.

    2014-01-01

    Electrolytes with high ionic diffusivity at temperatures distinctively lower than the presently used ones are the prerequisite for the success of, e.g., solid oxide fuel cells. We have found a promising structure having an asymmetric but superior ionic mobility in the direction of the oxygen-ion current. Using a layering of zirconium and yttrium in the fluorite structure of zirconia, a high vacancy concentration and a low migration barrier in two dimensions are obtained, while the mobility in the third direction is basically sacrificed. According to our density functional theory calculations an electrolyte made of this structure could operate at a temperature reduced by ≈200∘C. Thus a window to a different class of electrolytes has been flung open. In our structure the price paid is a more complicated manufacturing method.

  18. Effect of ionic conductivity of zirconia electrolytes on polarization properties of various electrodes in SOFC

    SciTech Connect

    Watanabe, Masahiro; Uchida, Hiroyuki; Yoshida, Manabu

    1996-12-31

    Solid oxide fuel cells (SOFCs) have been intensively investigated because, in principle, their energy conversion efficiency is fairly high. Lowering the operating temperature of SOFCs from 1000{degrees}C to around 800{degrees}C is desirable for reducing serious problems such as physical and chemical degradation of the constructing materials. The object of a series of the studies is to find a clue for achieving higher electrode performances at a low operating temperature than those of the present level. Although the polarization loss at electrodes can be reduced by using mixed-conducting ceria electrolytes, or introducing the mixed-conducting (reduced zirconia or ceria) laver on the conventional zirconia electrolyte surface, no reports are available on the effect of such an ionic conductivity of electrolytes on electrode polarizations. High ionic conductivity of the electrolyte, of course, reduces the ohmic loss. However, we have found that the IR-free polarization of a platinum anode attached to zirconia electrolytes is greatly influenced by the ionic conductivity, {sigma}{sub ion}, of the electrolytes used. The higher the {sigma}{sub ion}, the higher the exchange current density, j{sub 0}, for the Pt anode in H{sub 2} at 800 {approximately} 1000{degrees}C. It was indicated that the H{sub 2} oxidation reaction rate was controlled by the supply rate of oxide ions through the Pt/zirconia interface which is proportional to the {sigma}{sub ion}. Recently, we have proposed a new concept of the catalyzed-reaction layers which realizes both high-performances of anodes and cathodes for medium-temperature operating SOFCs. We present the interesting dependence of the polarization properties of various electrodes (the SDC anodes with and without Ru microcatalysts, Pt cathode, La(Sr)MnO{sub 3} cathodes with and without Pt microcatalysts) on the {sigma}{sub ion} of various zirconia electrolytes at 800 {approximately} 1000{degrees}C.

  19. Dissimilar Crystal Dependence of Vanadium Oxide Cathodes in Organic Carbonate and Safe Ionic Liquid Electrolytes.

    PubMed

    Tartaj, Pedro; Amarilla, Jose M; Morales, Enrique; Vazquez-Santos, Maria B

    2016-01-27

    Advances in Li metal anode stabilization, solid-state electrolytes, and capabilities to insert a variety of active ions (Li(+), Na(+), Mg(2+), and Al(3+)) have renewed the interest in layered vanadium oxides. Here we show that crystal characteristics such as size and crystallinity are fundamental variables that control the dissimilar electrochemical capabilities of 1D vanadium oxides immersed in different electrolytes (organic carbonates and safe electrolytes containing 80% of ionic liquid). We show that this opposite behavior can be understood in terms of a subtle interplay between crystal characteristics (size and crystallinity), electrolyte degradability, and the ionic conductivity of the electrolyte. Thus, through this control we are able to obtain pure 1D vanadium oxides that show reversibility in carbonate electrolytes at a cutoff voltage of 1.5 V (voltage region where insertion of more than two lithium ions is possible). Furthermore, these materials are able to uptake ca. 1.0 mol of Li at a rate of 20C (1C = 295 mAh/g) and retain excellent capabilities (Coulombic efficiency of 98% after 200 cycles at a rate of 5C). Finally, what, to our knowledge, is really remarkable is that this optimization allows building vanadium oxide electrodes with an excellent electrochemical response in a safe electrolyte composition (80% of ionic liquid). Specifically, we reach uptakes also at a cutoff voltage of 1.5 V of ca. 1.0 mol of Li after 200 cycles at 5C (charge/discharge) with Coulombic efficiencies higher than 99.5%.

  20. Defect Physics and Ionic conduction in Solid Electrolyte Interphase for Lithium Ion Batteries

    NASA Astrophysics Data System (ADS)

    Pan, Jie; Cheng, Yang-Tse; Qi, Yue

    The ionic conduction through the solid electrolyte interphase (SEI) is important to the rate capability of the battery. The origin of ionic conduction in the SEI is defect formation and transport. In this study, we developed a theoretical method based on density functional theory to calculate the ionic conductivity in LiF, an important SEI component, in contact with electrode materials. Seventeen native defects with their relevant charge states were investigated to determine the dominant defects on various electrodes. The contacted electrode serves as a Li reservoir with adjustable Li chemical potential (μLi) for defect formation. The formation energy and diffusion barrier of defects were mapped to ionic conductivity by the Nernst-Einstein relationship. The main defect is Schottky pair in the intrinsic region and Li ion vacancy in the p-type region. The ionic conductivity is calculated to be approximately 10-31 S/cm when LiF is in contact with an anode but it can increase to 10-12 S/cm on a cathode. Comparing with other SEI components, the ionic conductivity is very low in LiF if it is coated on an anode surface. However, due to the low concentration of electronic carriers, LiF can act as a good passivation layer on the electrode and prevent further electrolyte decomposition. This work is supported by Department of Energy and National Science Foundation.

  1. Towards Li(Ni0.33Mn0.33Co0.33)O2/graphite batteries with ionic liquid-based electrolytes. I. Electrodes' behavior in lithium half-cells

    NASA Astrophysics Data System (ADS)

    Simonetti, E.; Maresca, G.; Appetecchi, G. B.; Kim, G.-T.; Loeffler, N.; Passerini, S.

    2016-11-01

    Lithium cells based on NMC cathodes or graphite anodes and ionic liquid-based electrolyte mixtures are investigated. The electrode tapes, using water-soluble natural binders, as well as the ionic liquid materials, are prepared through eco-friendly routes involving H2O as the only processing solvent. The Li/NMC and Li/graphite half-cells are studied by cyclic voltammetry, impedance spectroscopy and galvanostatic cycling tests at different temperatures. The results herein reported, demonstrate the performance improvement in terms of cycling behavior and ageing resistance, granted by the ionic liquid mixtures with respect to the electrolytes reported in literature based on a single ionic liquid.

  2. Ionic liquid processing of cellulose.

    PubMed

    Wang, Hui; Gurau, Gabriela; Rogers, Robin D

    2012-02-21

    Utilization of natural polymers has attracted increasing attention because of the consumption and over-exploitation of non-renewable resources, such as coal and oil. The development of green processing of cellulose, the most abundant biorenewable material on Earth, is urgent from the viewpoints of both sustainability and environmental protection. The discovery of the dissolution of cellulose in ionic liquids (ILs, salts which melt below 100 °C) provides new opportunities for the processing of this biopolymer, however, many fundamental and practical questions need to be answered in order to determine if this will ultimately be a green or sustainable strategy. In this critical review, the open fundamental questions regarding the interactions of cellulose with both the IL cations and anions in the dissolution process are discussed. Investigations have shown that the interactions between the anion and cellulose play an important role in the solvation of cellulose, however, opinions on the role of the cation are conflicting. Some researchers have concluded that the cations are hydrogen bonding to this biopolymer, while others suggest they are not. Our review of the available data has led us to urge the use of more chemical units of solubility, such as 'g cellulose per mole of IL' or 'mol IL per mol hydroxyl in cellulose' to provide more consistency in data reporting and more insight into the dissolution mechanism. This review will also assess the greenness and sustainability of IL processing of biomass, where it would seem that the choices of cation and anion are critical not only to the science of the dissolution, but to the ultimate 'greenness' of any process (142 references).

  3. Electrochemical Behavior of PEDOT/Lignin in Ionic Liquid Electrolytes: Suitable Cathode/Electrolyte System for Sodium Batteries.

    PubMed

    Casado, Nerea; Hilder, Matthias; Pozo-Gonzalo, Cristina; Forsyth, Maria; Mecerreyes, David

    2017-02-15

    Biomass-derived polymers, such as lignin, contain quinone/ hydroquinone redox moieties that can be used to store charge. Composites based on the biopolymer lignin and several conjugated polymers have shown good charge-storage properties. However, their performance has been only studied in acidic aqueous media limiting their applications mainly to supercapacitors. Here, we show that PEDOT/lignin (PEDOT: poly(3,4-ethylenedioxythiophene)) biopolymers are electroactive in aprotic ionic liquids (ILs) and we move a step further by assembling sodium full cell batteries using PEDOT/lignin as electrode material and IL electrolytes. Thus, the electrochemical activity and cycling of PEDOT/lignin electrodes was investigated in 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide (BMPyrTFSI), 1-butyl-1-methylpyrrolidinium bis(fluorosulfonyl)imide (BMPyrFSI), 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMImTFSI) and 1-ethyl-3-methylimidazolium bis(fluorosulfonyl)imide (EMImFSI) IL electrolytes. The effects of water and sodium salt addition to the ILs were investigated to obtain optimum electrolyte systems for sodium batteries. Finally, sodium batteries based on PEDOT/lignin cathode with imidazolium-based IL electrolyte showed higher capacity values than pyrrolidinium ones, reaching 70 mAhg(-1) . Our results demonstrate that PEDOT/lignin composites can serve as low cost and sustainable cathode materials for sodium batteries.

  4. Lithium-sulphur battery with activated carbon cloth-sulphur cathode and ionic liquid as electrolyte

    NASA Astrophysics Data System (ADS)

    Swiderska-Mocek, Agnieszka; Rudnicka, Ewelina

    2015-01-01

    In this study a binder-free activated carbon cloth-sulphur (ACC-S) composite cathode is presented. Such a cathode was obtained using the impregnating technique of microporous activated carbon cloth with elemental melted sulphur. The surface morphology of an activated carbon cloth-sulphur electrode was studied using a scanning electron microscope (SEM), which was equipped with an EDX spectroscopy attachment. Electrochemical properties of the ACC-S composite cathode was tested in an ionic liquid electrolyte consisting of 1-ethyl-3-methylimidazolium bis(trifluoromethanesulphonyl)imide (EtMeImNTf2) and bis(trifluoromethanesulphonyl)imide (LiNTf2). The ACC-sulphur cathode working together with lithium anode was tested with the use of cyclic voltammetry (CV), galvanostatic charge/discharge cycles and electrochemical impedance spectroscopy (EIS). The capacity and cyclic stability of the ACC-S composite cathode were much better than those for the sulphur cathode (a mixture of sulphur from graphene nanoplatelets and carbon black) tested in the same ionic liquid electrolyte. The ACC-sulphur cathode showed good cyclability and coulombic efficiency (99%) with the ionic liquid electrolyte. The reversible capacity of the ACC-S|electrolyte|Li cell was ca. 830 mAh g-1 after 50 cycles.

  5. Structure and ionic conductivity of block copolymer electrolytes over a wide salt concentration range

    NASA Astrophysics Data System (ADS)

    Chintapalli, Mahati; Le, Thao; Venkatesan, Naveen; Thelen, Jacob; Rojas, Adriana; Balsara, Nitash

    Block copolymer electrolytes are promising materials for safe, long-lasting lithium batteries because of their favorable mechanical and ion transport properties. The morphology, phase behavior, and ionic conductivity of a block copolymer electrolyte, SEO mixed with LiTFSI was studied over a wide, previously unexplored salt concentration range using small angle X-ray scattering, differential scanning calorimetry and ac impedance spectroscopy, respectively. SEO exhibits a maximum in ionic conductivity at twice the salt concentration that PEO, the homopolymer analog of the ion-containing block, does. This finding is contrary to prior studies that examined a more limited range of salt concentrations. In SEO, the phase behavior of the PEO block and LiTFSI closely resembles the phase behavior of homopolymer PEO and LiTFSI. The grain size of the block copolymer morphology was found to decrease with increasing salt concentration, and the ionic conductivity of SEO correlates with decreasing grain size. Structural effects impact the ionic conductivity-salt concentration relationship in block copolymer electrolytes. SEO: polystyrene-block-poly(ethylene oxide); also PS-PEO LiTFSI: lithium bis(trifluoromethanesulfonyl imide

  6. Nanocrystalline porous TiO2 electrode with ionic liquid impregnated solid polymer electrolyte for dye sensitized solar cells.

    PubMed

    Singh, Pramod K; Kim, Kang-Wook; Kim, Ki-Il; Park, Nam-Gyu; Rhee, Hee-Woo

    2008-10-01

    This communication reports the detailed fabrication of electrodes and solid polymer electrolyte with ionic liquid (IL) as an electrolyte for dye sensitized solar cell (DSSC). Thick porous TiO2 film has been obtained by spreading and sintering TiO2 colloidal paste using "doctor blade" and characterized by SEM, TEM and XRD. The polymer electrolyte was PEO:KI/I2 incorporated with 1-ethyl 3-methylimidazolium thiocyanate (EMImSCN) as IL. Dispersal of IL in the polymer electrolyte improved the ionic conductivity and cell efficiency.

  7. Electrolyte Solvation and Ionic Association. V. Acetonitrile-Lithium Bis(fluorosulfonyl)imide (LiFSI) Mixtures

    SciTech Connect

    Han, Sang D.; Borodin, Oleg; Seo, D. M.; Zhou, Zhi B.; Henderson, Wesley A.

    2014-09-30

    Electrolytes with the salt lithium bis(fluorosulfonyl)imide (LiFSI) have been evaluated relative to comparable electrolytes with other lithium salts. Acetonitrile (AN) has been used as a model electrolyte solvent. The information obtained from the thermal phase behavior, solvation/ionic association interactions, quantum chemical (QC) calculations and molecular dynamics (MD) simulations (with an APPLE&P many-body polarizable force field for the LiFSI salt) of the (AN)n-LiFSI mixtures provides detailed insight into the coordination interactions of the FSI- anions and the wide variability noted in the electrolyte transport property (i.e., viscosity and ionic conductivity).

  8. Li-Doped Ionic Liquid Electrolytes: From Bulk Phase to Interfacial Behavior

    NASA Technical Reports Server (NTRS)

    Haskins, Justin B.; Lawson, John W.

    2016-01-01

    Ionic liquids have been proposed as candidate electrolytes for high-energy density, rechargeable batteries. We present an extensive computational analysis supported by experimental comparisons of the bulk and interfacial properties of a representative set of these electrolytes as a function of Li-salt doping. We begin by investigating the bulk electrolyte using quantum chemistry and ab initio molecular dynamics to elucidate the solvation structure of Li(+). MD simulations using the polarizable force field of Borodin and coworkers were then performed, from which we obtain an array of thermodynamic and transport properties. Excellent agreement is found with experiments for diffusion, ionic conductivity, and viscosity. Combining MD simulations with electronic structure computations, we computed the electrochemical window of the electrolytes across a range of Li(+)-doping levels and comment on the role of the liquid environment. Finally, we performed a suite of simulations of these Li-doped electrolytes at ideal electrified interfaces to evaluate the differential capacitance and the equilibrium Li(+) distribution in the double layer. The magnitude of differential capacitance is in good agreement with our experiments and exhibits the characteristic camel-shaped profile. In addition, the simulations reveal Li(+) to be highly localized to the second molecular layer of the double layer, which is supported by additional computations that find this layer to be a free energy minimum with respect to Li(+) translation.

  9. Electrolytes For Electrooptic Devices Comprising Ionic Liqu Ids

    DOEpatents

    Warner, Benjamin P.; McCleskey, T. Mark; Agrawal, Anoop; Cronin, John P.; Tonazzi, Juan C. L.; Burrell, Anthony K.

    2005-02-08

    Electrolyte solutions of soluble bifunctional redox dyes in molten salt solvent may be used to prepare electrooptic devices with enhanced stability toward ultraviolet radiation. The solvents include lithium or quaternary ammonium cations, and perfluorinated sulfonylimide anions selected from trifluoromethylsulfonate (CF.sub.3 SO.sub.3.sup.-), bis(trifluoromethylsulfonyl)imide ((CF.sub.3 SO.sub.2).sub.2 N.sup.-), bis(perfluoroethylsulfonyl)imide ((CF.sub.3 CF.sub.2 SO.sub.2).sub.2 N.sup.-) and tris(trifluoromethylsulfonyl)methide ((CF.sub.3 SO.sub.2).sub.3 C.sup.-).

  10. State of ions in electrolyte solutions in the ionic-plasma approximation

    SciTech Connect

    Baldanov, M.M.; Mokhosoev, M.V.

    1986-04-01

    This paper examines the state of ions in the framework of the concept of an ionic plasma. Results are presented of the evaluations of the equivalent conductivity of lithium chloride in aqueous solutions at 18 C. The Debye-Falkenhagne effect and the Wien effect are discussed. The proposed interpretation of the state of ions in electrolyte solutions gives a more natural and more systematic explanation for such factors as the Debye-Falkenhagen dispersion of the electrical conductivity, the Wien effect, and the activity coefficients of electrolytes.

  11. Ionic Liquid Electrolytes for Li–Air Batteries: Lithium Metal Cycling

    PubMed Central

    Grande, Lorenzo; Paillard, Elie; Kim, Guk-Tae; Monaco, Simone; Passerini, Stefano

    2014-01-01

    In this work, the electrochemical stability and lithium plating/stripping performance of N-butyl-N-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide (Pyr14TFSI) are reported, by investigating the behavior of Li metal electrodes in symmetrical Li/electrolyte/Li cells. Electrochemical impedance spectroscopy measurements and galvanostatic cycling at different temperatures are performed to analyze the influence of temperature on the stabilization of the solid electrolyte interphase (SEI), showing that TFSI-based ionic liquids (ILs) rank among the best candidates for long-lasting Li–air cells. PMID:24815072

  12. Ionic liquid electrolytes for Li-air batteries: lithium metal cycling.

    PubMed

    Grande, Lorenzo; Paillard, Elie; Kim, Guk-Tae; Monaco, Simone; Passerini, Stefano

    2014-05-08

    In this work, the electrochemical stability and lithium plating/stripping performance of N-butyl-N-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide (Pyr14TFSI) are reported, by investigating the behavior of Li metal electrodes in symmetrical Li/electrolyte/Li cells. Electrochemical impedance spectroscopy measurements and galvanostatic cycling at different temperatures are performed to analyze the influence of temperature on the stabilization of the solid electrolyte interphase (SEI), showing that TFSI-based ionic liquids (ILs) rank among the best candidates for long-lasting Li-air cells.

  13. Effect of poly(ethylene oxide) on ionic conductivity and electrochemical properties of poly(vinylidenefluoride) based polymer gel electrolytes prepared by electrospinning for lithium ion batteries

    NASA Astrophysics Data System (ADS)

    Prasanth, Raghavan; Shubha, Nageswaran; Hng, Huey Hoon; Srinivasan, Madhavi

    2014-01-01

    Effect of poly(ethylene oxide) on the electrochemical properties of polymer electrolyte based on electrospun, non-woven membrane of PVdF is demonstrated. Electrospinning process parameters are controlled to get a fibrous membrane consisting of bead-free, uniformly dispersed thin fibers with diameter in the range of 1.5-1.9 μm. The membrane with good mechanical strength and porosity exhibits high uptake when activated with the liquid electrolyte of lithium salt in a mixture of organic solvents. The polymer gel electrolyte shows ionic conductivity of 4.9 × 10-3 S cm-1 at room temperature. Electrochemical performance of the polymer gel electrolyte is evaluated in Li/polymer electrolyte/LiFePO4 coin cell. Good performance with low capacity fading on charge-discharge cycling is demonstrated.

  14. Ionic enhancement of silica surface nanowear in electrolyte solutions.

    PubMed

    Vakarelski, Ivan U; Teramoto, Naofumi; McNamee, Cathy E; Marston, Jeremy O; Higashitani, Ko

    2012-11-20

    The nanoscale wear and friction of silica and silicon nitride surfaces in aqueous electrolyte solutions were investigated by using sharp atomic force microscope (AFM) cantilever tips coated with silicon nitride. Measurements were carried out in aqueous solutions of varying pH and in monovalent and divalent cation chloride and nitrate solutions. The silica surface was shown to wear strongly in solutions of high pH (≈11.0), as expected, but the presence of simple cations, such as Cs(+) and Ca(2+), was shown to dramatically effect the wear depth and friction force for the silica surface. In the case of monovalent cations, their hydration enthalpies correlated well with the wear and friction. The weakest hydrated cation of Cs(+) showed the most significant enhancement of wear and friction. In the case of divalent cations, a complex dependence on the type of cation was found, where the type of anion was also seen to play an important role. The CaCl(2) solution showed the anomalous enhancement of wear depth and friction force, although the solution of Ca(NO(3))(2) did not. The present results obtained with an AFM tip were also compared with previous nanotribology studies of silica surfaces in electrolyte solutions, and possible molecular mechanisms as to why cations enhance the wear and friction were also discussed.

  15. Nonaqueous System of Iron-Based Ionic Liquid and DMF for the Oxidation of Hydrogen Sulfide and Regeneration by Electrolysis.

    PubMed

    Guo, Zhihui; Zhang, Tingting; Liu, Tiantian; Du, Jun; Jia, Bing; Gao, Shujing; Yu, Jiang

    2015-05-05

    To improve the hydrogen sulfide removal efficiency with the application of an iron-based imidazolium chloride ionic liquid (Fe(III)-IL) as desulfurizer, Fe(II) and N,N-dimethylformamide (DMF) are introduced to Fe(III)-IL to construct a new nonaqueous desulfurization system (Fe(III/II)-IL/DMF). Following desulfurization, the system can be regenerated using the controlled-potential electrolysis method. The addition of Fe(II) in Fe(III)-IL is beneficial for the hydrogen sulfide removal and the electrochemical regeneration of the desulfurizer. The addition of DMF in Fe(III/II)-IL does not change the structure of Fe(III/II)-IL but clearly decreases the acidity, increases the electrolytic current, and decreases the stability of the Fe-Cl bond in Fe(III/II)-IL. Fe(III/II)-IL/DMF can remove hydrogen sulfide and can be regenerated through an electrochemical method more efficiently than can Fe(III/II)-IL. After six cycles, the desulfurization efficiency remains higher than 98%, and the average conversion rate of Fe(II) is essentially unchanged. No sulfur peroxidation occurs, and the system remains stable. Therefore, this new nonaqueous system has considerable potential for removing H2S in pollution control applications.

  16. Ionic conductivity and dielectric permittivity of polymer electrolyte plasticized with polyethylene glycol

    NASA Astrophysics Data System (ADS)

    Das, S.; Ghosh, A.

    2016-05-01

    We have studied ionic conductivity and dielectric permittivity of PEO-LiClO4 solid polymer electrolyte plasticized with polyethylene glycol (PEG). The temperature dependence of the ionic conductivity has been well interpreted using Vogel-Tamman-Fulcher equation. The maximum dielectric constant is observed for 30 wt. % of PEG content. To get further insights into the ion dynamics, the complex dielectric permittivity has been studied with Havriliak-Negami function. The variation of relaxation time with inverse temperature obtained from HN formalism follows VTF nature.

  17. Direct probing of a polymer electrolyte/luminescent conjugated polymer mixed ionic/electronic conductor.

    PubMed

    Hu, Yufeng; Gao, Jun

    2009-12-30

    What will happen if one brings two metallic probes into direct contact with a polymer film and apply a voltage bias? We demonstrate that, for a mixed ionic/electronic conductor containing a luminescent conjugated polymer and a polymer electrolyte, it is possible to induce strong in situ electrochemical doping of the luminescent polymer and form a dynamic light-emitting p-n junction. Using time-lapse fluorescence imaging, we have visualized p- and n-doping of various shapes and shades, p-n junction electroluminescence, and the effects of voltage reversal. The direct probing technique offers great simplicity and versatility for studying luminescent mixed ionic/electronic conductors.

  18. Investigation of ionic mobility in NASICON-type solid electrolytes

    NASA Astrophysics Data System (ADS)

    Vyalikh, A.; Vizgalov, V.; Itkis, D. M.; Meyer, D. C.

    2016-10-01

    Impedance spectroscopy and 7Li NMR have been applied to characterize the lithium conducting glass-ceramics membranes of the Li1.5Al0.5Ge1.5(PO4)3 composition with the NASICON-type structure. The 7Li NMR spectra and T1 relaxation times have been compared for the precursor glass and two glass-ceramics annealed for 2 and 6 hours, and analysed with respect to the ionic conductivity in these materials. The 7Li static NMR spectra reveal two components in the glass-ceramics samples: A quadrupole pattern with CQ of 38.7 kHz and 32.5 kHz, and a narrow signal of the Lorentzian or Gaussian lineshape for the samples annealed for 2 and 6 hours, respectively. Variation of the lineshape and the deconvolution parameters point out to the modification of the NASICON framework in the former, which affects the conductivity channels towards improved movement of lithium ions. The NMR data correlate with the conductivity measurements demonstrating enhanced ionic mobility in the glass-ceramics annealed for 2 hours. The 7Li NMR relaxation data seem to be very sensitive to the species with different mobility and reveal the presence of an additional minor component, which can be responsible for decrease of conductivity at longer thermal treatment.

  19. Roles of Electrolyte Characterization on Bauxite Electrolysis Desulfurization with Regeneration and Recycling

    NASA Astrophysics Data System (ADS)

    Gong, Xuzhong; Wang, Zhi; Zhuang, Siyuan; Wang, Dong; Wang, Yuhua; Wang, Mingyong

    2017-02-01

    The recycling of NaCl used as supporting electrolyte for bauxite electrolysis was carried out in this study. The electrolyte was regenerated by adding anhydrous CaCl2 into the solution after filtration, and effects of electrolyte characterization on bauxite electrolysis were examined by observing the change in desulfurization ratio and cell voltage. The results indicated that the desulfurization ratio increased with increasing recycling times of electrolyte. In the meantime, the increase in recycling times has led to the decrease in pH value as well as the increase in Fe ion concentration in the electrolyte, which were the main reasons for the increase in the desulfurization ratio with increasing recycling of electrolyte. The pH value of electrolyte after second electrolysis was lower than 1.5, and the desulfurization ratio increased obviously due to the increase in Fe3+ concentration and suppression of jarosite formation. The increase in Ca2+ concentration did not apparently change desulfurization ratio and anode surface activity. However, with Ca2+ addition, the cathode surface was covered by CaSO4·nH2O, thus resulting in the increase of cell voltage.

  20. Process for electrolytically preparing uranium metal

    DOEpatents

    Haas, Paul A.

    1989-01-01

    A process for making uranium metal from uranium oxide by first fluorinating uranium oxide to form uranium tetrafluoride and next electrolytically reducing the uranium tetrafluoride with a carbon anode to form uranium metal and CF.sub.4. The CF.sub.4 is reused in the fluorination reaction rather than being disposed of as a hazardous waste.

  1. Process for electrolytically preparing uranium metal

    DOEpatents

    Haas, Paul A.

    1989-08-01

    A process for making uranium metal from uranium oxide by first fluorinating uranium oxide to form uranium tetrafluoride and next electrolytically reducing the uranium tetrafluoride with a carbon anode to form uranium metal and CF.sub.4. The CF.sub.4 is reused in the fluorination reaction rather than being disposed of as a hazardous waste.

  2. [Regeneration processes in various species of planarians].

    PubMed

    Sheĭman, I M; Kreshchenko, N D; Netreba, M V

    2010-01-01

    Blastema growth and functional maturation of the pharynx during regeneration in various planarian species were compared. The intensity of blastema growth was highest in Polycelis tenuis; the lowest, in Schmidtea mediterranea. In the sexual and asexual races of Girardia tigrina blastema growth differed inconsiderably. The function of the pharynx during the regeneration of caudal fragments lacking pharynx was manifested in G. tigrina in the usual amount of time, while in the regeneration of head fragments lacking pharynx, this function occured earlier. In other planarian species of the other two typed, the times of pharynx regeneration had no regular character and took longer compared to the same process in G. tigrina.

  3. Ionic liquid-based membranes as electrolytes for advanced lithium polymer batteries.

    PubMed

    Navarra, M A; Manzi, J; Lombardo, L; Panero, S; Scrosati, Bruno

    2011-01-17

    Gel-type polymer electrolytes are formed by immobilizing a solution of lithium N,N-bis(trifluoromethanesulfonyl)imide (LiTFSI) in N-n-butyl-N-ethylpyrrolidinium N,N-bis(trifluoromethanesulfonyl)imide (Py₂₄TFSI) ionic liquid (IL) with added mixtures of organic solvents, such as ethylene, propylene and dimethyl carbonates (EC, PC, and DMC, respectively), into a poly(vinylidenefluoride-co-hexafluoropropylene) (PVdF-HFP) matrix, and their properties investigated. The addition of the organic solvent mixtures results in an improvement of the ionic conductivity and in the stabilization of the interface with the lithium electrode. Conductivity values in the range of 10⁻³-10⁻²  S cm⁻¹ are obtained in a wide temperature range. These unique properties allow the effective use of these membranes as electrolytes for the development of advanced polymer batteries based on a lithium metal anode and an olivine-type lithium iron phosphate cathode.

  4. Sodium-ion electrolytes based on ionic liquids: a role of cation-anion hydrogen bonding.

    PubMed

    Chaban, Vitaly V; Andreeva, Nadezhda A

    2016-08-01

    Recent success of the sodium-ion batteries fosters an academic interest for their investigation. Room-temperature ionic liquids (RTILs) constitute universal solvents providing non-volatility and non-flammability to electrolytes. In the present work, we consider four families of RTILs as prospective solvents for NaBF4 and NaNO3 with an inorganic salt concentration of 25 and 50 mol%. We propose a methodology to rate RTILs according to their solvation capability using parameters of the computed radial distribution functions. Hydrogen bonds between the cations and the anions of RTILs were found to indirectly favor sodium solvation, irrespective of the particular RTIL and its concentration. The best performance was recorded in the case of cholinium nitrate. The reported observations and correlations of ionic structures and properties offer important assistance to an emerging field of sodium-ion batteries. Graphical Abstract Sodium-ion electrolytes.

  5. Tandem dissolution of UO3 in amide-based acidic ionic liquid and in situ electrodeposition of UO2 with regeneration of the ionic liquid: a closed cycle

    DOE PAGES

    Wanigasekara, Eranda; Freiderich, John W.; Sun, Xiao-Guang; ...

    2016-05-19

    A closed cycle is demonstrated for the tandem dissolution and electroreduction of UO3 to UO2 with regeneration of the acidic ionic liquid. The dissolution is achieved by use of the acidic ionic liquid N,N-dimethylacetimidium bis(trifluoromethanesulfonimide) in 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonimide) serving as the diluent. Bulk electrolysis performed at 1.0 V vs. Ag reference yields a dark brown-black uranium deposit (UO2) on the cathode. Anodic oxidation of water in the presence of dimethylacetamide regenerates the acidic ionic liquid. We have demonstrated the individual steps in the cycle together with a sequential dissolution, electroreduction, and regeneration cycle.

  6. DEVELOPMENT AND SELECTION OF IONIC LIQUID ELECTROLYTES FOR HYDROXIDE CONDUCTING POLYBENZIMIDAZOLE MEMBRANES IN ALKALINE FUEL CELLS

    SciTech Connect

    Fox, E.

    2012-05-01

    Alkaline fuel cell (AFC) operation is currently limited to specialty applications such as low temperatures and pure HO due to the corrosive nature of the electrolyte and formation of carbonates. AFCs are the cheapest and potentially most efficient (approaching 70%) fuel cells. The fact that non-Pt catalysts can be used, makes them an ideal low cost alternative for power production. The anode and cathode are separated by and solid electrolyte or alkaline porous media saturated with KOH. However, CO from the atmosphere or fuel feed severely poisons the electrolyte by forming insoluble carbonates. The corrosivity of KOH (electrolyte) limits operating temperatures to no more than 80°C. This chapter examines the development of ionic liquids electrolytes that are less corrosive, have higher operating temperatures, do not chemically bond to CO and enable alternative fuels. Work is detailed on the IL selection and characterization as well as casting methods within the polybenzimidazole based solid membrane. This approach is novel as it targets the root of the problem (the electrolyte) unlike other current work in alkaline fuel cells which focus on making the fuel cell components more durable.

  7. Perfluoro anion based binary and ternary ionic liquids as electrolytes for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Lin, Hsi-Hsin; Peng, Jia-De; Suryanarayanan, V.; Velayutham, D.; Ho, Kuo-Chuan

    2016-04-01

    In this work, eight new ionic liquids (ILs) based on triethylammonium (TEA) or n-methylpiperidinium (NMP) cations and perfluoro carboxylate (PFC) anions having different carbon chain lengths are synthesized and their physico-chemical properties such as density, decomposition temperature, viscosity and conductivity are determined. Photovoltaic characteristics of dye-sensitized solar cells (DSSCs) with binary ionic liquids electrolytes, containing the mixture of the synthesized ILs and 1-methyl-3-propyl imidazolium iodide (PMII) (v/v = 35/65), are evaluated. Among the different ILs, solar cells containing NMP based ILs show higher VOC than that of TEA, whereas, higher JSC is noted for the DSSCs incorporated with the latter when compared to the former. Further, the photo-current of the DSSCs decreases with the increase of the carbon chain length of perfluoro carboxylate anionic group of ILs. The cell performance of the DSSC containing ternary ionic liquids-based electrolytes compose of NMP-2C/TEA-2C/PMII (v/v/v = 28/7/65) exhibits a JSC of 12.99 mA cm-2, a VOC of 639.0 mV, a FF of 0.72, and a cell efficiency of 6.01%. The extraordinary durability of the DSSC containing the above combination of electrolytes stored in dark at 50 °C is proved to be unfailing up to 1200 h.

  8. Ionic liquid electrolyte based on S-propyltetrahydrothiophenium iodide for dye-sensitized solar cells

    SciTech Connect

    Guo, Lei; Pan, Xu; Zhang, Changneng; Liu, Weiqing; Wang, Meng; Fang, Xiaqin; Dai, Songyuan

    2010-03-15

    A new ionic liquid S-propyltetrahydrothiophenium iodide (T{sub 3}I) was developed as the solvent and iodide ion source in electrolyte for dye-sensitized solar cells. The electrochemical behavior of the I{sub 3}{sup -}/I{sup -} redox couple and effect of additives in this ionic liquid system was tested and the results showed that this ionic liquid electrolyte revealed good conducting abilities and potential application for solar devices. The effects of LiI and dark-current inhibitors were investigated. The dye-sensitized solar cell with the electrolyte (0.1 mol L{sup -1} LiI, 0.35 mol L{sup -1} I{sub 2}, 0.5 mol L{sup -1} NMBI in pure T{sub 3}I) gave short-circuit photocurrent density (J{sub sc}) of 11.22 mA cm{sup 2}, open-circuit voltage (V{sub oc}) of 0.61 V and fill factor (FF) of 0.51, corresponding to the photoelectric conversion efficiency ({eta}) of 3.51% under one Sun (AM1.5). (author)

  9. Characteristics of an ionic liquid electrolyte for sodium-ion batteries

    NASA Astrophysics Data System (ADS)

    Hasa, Ivana; Passerini, Stefano; Hassoun, Jusef

    2016-01-01

    We study the liquid mixture of sodium bis(trifluoromethanesulfonyl)imide in N-butyl-N-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide (Pyr14TFSI-NaTFSI) for application in sodium-ion batteries. The ionic liquid-based electrolyte is characterized in terms of electrochemical and thermal properties. Ionic conductivity and electrochemical stability windows are evaluated through electrochemical impedance spectroscopy (EIS) measurements and voltammetry tests, respectively. The thermal stability is evaluated by differential scanning calorimetry (DSC) and thermo-gravimetric analysis (TGA). Moreover, the suitability of the IL-electrolyte is preliminary verified in half and in full-cells at room temperature, using P2-Na0.6Ni0.22Fe0.11Mn0.66O2 layered oxide cathode and nanostructured Sb-C composite anode. The cell shows promising characteristics with a working voltage of about 2.7 V and a delivered capacity of about 100 mAh g-1. Despite requiring further optimization in terms of cycle life and energy density, the data here reported suggest the suitability of the ionic liquid electrolyte for application in sodium-ion battery.

  10. Structural and electrochemical properties of succinonitrile-based gel polymer electrolytes: role of ionic liquid addition.

    PubMed

    Suleman, Mohd; Kumar, Yogesh; Hashmi, S A

    2013-06-20

    Experimental studies on the novel compositions of gel polymer electrolytes, comprised of plastic crystal succinonitrile (SN) dispersed with pyrrolidinium and imidazolium-based ionic liquids (ILs) entrapped in a host polymer poly(vinylidine fluoride-co-hexafluoropropylene) (PVdF-HFP), are reported. The gel electrolytes are in the form of free-standing films with excellent mechanical, thermal, and electrochemical stability. The introduction of even a small content (~1 wt %) of ionic liquid (1-butyl-1-methylpyrrolidinium bis(trifluoromethyl-sulfonyl)imide (BMPTFSI) or 1-ethyl-3-methylimidazolium trifluoromethanesulfonate (EMITf) in the PVdF-HFP/SN system (1:4 w/w) enhances the electrical conductivity by 4 orders of magnitude, that is, from ~10(-7) to ~10(-3) S cm(-1) at room temperature. The structural changes due to the entrapment of SN or SN/ILs mixtures and ion-SN-polymer interactions are examined by Fourier transform infrared (FTIR)/Raman spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD), and differential scanning calorimmetry (DSC). Various physicochemical properties and fast ion conduction in the gel polymer membranes show their promising characteristics as electrolytes in different ionic devices including supercapacitors.

  11. Electrolyte Solvation and Ionic Association. VI. Acetonitrile-Lithium Salt Mixtures. Highly Associated Salts Revisited

    SciTech Connect

    Borodin, Oleg; Han, Sang D.; Daubert, James S.; Seo, D. M.; Yun, Sung-Hyun; Henderson, Wesley A.

    2015-01-14

    Molecular dynamics (MD) simulations of acetonitrile (AN) mixtures with LiBF4, LiCF3SO3 and LiCF3CO2 provide extensive details about the molecular- and mesoscale-level solution interactions and thus explanations as to why these electrolytes have very different thermal phase behavior and electrochemical/physicochemical properties. The simulation results are in full accord with a previous experimental study of these (AN)n-LiX electrolytes. This computational study reveals how the structure of the anions strongly influences the ionic association tendency of the ions, the manner in which the aggregate solvates assemble in solution and the length of time in which the anions remain coordinated to the Li+ cations in the solvates which result in dramatic variations in the transport properties of the electrolytes.

  12. Improved dye-sensitized solar cells by composite ionic liquid electrolyte incorporating layered titanium phosphate

    SciTech Connect

    Cheng, Ping; Lan, Tian; Wang, Wanjun; Wu, Haixia; Yang, Haijun; Guo, Shouwu

    2010-05-15

    We reported a composite electrolyte prepared by incorporating layered {alpha}-titanium phosphate ({alpha}-TiP) into a binary ionic liquid of 1-propyl-3-methylimidazolium iodide (PMII) and 1-ethyl-3-methylimidazolium tetrafluoroborate (EmimBF{sub 4}) (volume ratio, 13:7) electrolyte. The addition of {alpha}-TiP markedly improved the photovoltaic properties of dye-sensitized solar cells (DSSCs) compared to that without {alpha}-TiP. The enhancement was explained by improved diffusion of tri-iodide (I{sub 3}{sup -}) ions, suppressed electron recombination with I{sub 3}{sup -} in the electrolyte and increased lifetime of electrons in mesoscopic TiO{sub 2} film. (author)

  13. Three-dimensional ionic conduction in the strained electrolytes of solid oxide fuel cells

    NASA Astrophysics Data System (ADS)

    Han, Yupei; Zou, Minda; Lv, Weiqiang; Mao, Yiwu; Wang, Wei; He, Weidong

    2016-05-01

    Flexible power sources including fuel cells and batteries are the key to realizing flexible electronic devices with pronounced foldability. To understand the bending effects in these devices, theoretical analysis on three-dimensional (3-D) lattice bending is necessary. In this report, we derive a 3-D analytical model to analyze the effects of electrolyte crystal bending on ionic conductivity in flexible solid-state batteries/fuel cells. By employing solid oxide fuel cells as a materials' platform, the intrinsic parameters of bent electrolyte materials, including lattice constant, Young's modulus, and Poisson ratio, are evaluated. Our work facilitates the rational design of highly efficient flexible electrolytes for high-performance flexible device applications.

  14. Carbon nanotube spaced graphene aerogels with enhanced capacitance in aqueous and ionic liquid electrolytes

    NASA Astrophysics Data System (ADS)

    Shao, Qingguo; Tang, Jie; Lin, Yuexian; Li, Jing; Qin, Faxiang; Yuan, Jinshi; Qin, Lu-Chang

    2015-03-01

    Carbon nanotube spaced graphene aerogels have been prepared by a hydrothermal method and used for supercapacitor applications. The specific surface area and specific capacitance can be controlled by tuning the amount of added carbon nanotubes. The as-prepared composite aerogels retain the advantage of aerogel structure in providing macropores to ensure electrodes fast wetted by the electrolyte ions and also possess additional mesopores created by the carbon nanotube spacers for more ion adsorption. Benefited from that, the composite aerogels exhibit significantly enhanced supercapacitor properties in both aqueous and ionic liquid electrolyte. Compared with graphene aerogels, the composite aerogels show a 37% larger specific capacitance of 245.5 F g-1 at a current density of 2.5 A g-1 and high rate capability of 197.0 F g-1 at a high current density of 80 A g-1 in aqueous electrolyte. Moreover, the composite aerogels deliver a 33% larger specific capacitance of 183.3 F g-1 at 0.5 A g-1 and a high energy density of 80 Wh kg-1 when using an ionic liquid (EMIMBF4) as the electrolyte.

  15. Polymeric ionic liquid-plastic crystal composite electrolytes for lithium ion batteries

    NASA Astrophysics Data System (ADS)

    Li, Xiaowei; Zhang, Zhengxi; Li, Sijian; Yang, Li; Hirano, Shin-ichi

    2016-03-01

    In this work, composite polymer electrolytes (CPEs), that is, 80%[(1-x)PIL-(x)SN]-20%LiTFSI, are successfully prepared by using a pyrrolidinium-based polymeric ionic liquid (P(DADMA)TFSI) as a polymer host, succinonitrile (SN) as a plastic crystal, and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) as a lithium salt. XRD and DSC measurements confirm that the as-obtained CPEs have amorphous structures. The 80%[50%PIL-50%SN]-20%LiTFSI (50% SN) electrolyte reveals a high room temperature ionic conductivity of 5.74 × 10-4 S cm-1, a wide electrochemical window of 5.5 V, as well as good mechanical strength with a Young's modulus of 4.9 MPa. Li/LiFePO4 cells assembled with the 50% SN electrolyte at 0.1C rate can deliver a discharge capacity of about 150 mAh g-1 at 25 °C, with excellent capacity retention. Furthermore, such cells are able to achieve stable discharge capacities of 131.8 and 121.2 mAh g-1 at 0.5C and 1.0C rate, respectively. The impressive findings demonstrate that the electrolyte system prepared in this work has great potential for application in lithium ion batteries.

  16. Lithium-Ion-Conducting Electrolytes: From an Ionic Liquid to the Polymer Membrane

    PubMed Central

    Fernicola, A.; Weise, F. C.; Greenbaum, S. G.; Kagimoto, J.; Scrosati, B.; Soleto, A.

    2009-01-01

    This work concerns the design, the synthesis, and the characterization of the N-butyl-N-ethylpiperidinium N,N-bis(trifluoromethane)sulfonimide (PP24TFSI) ionic liquid (IL). To impart Li-ion transport, a suitable amount of lithium N,N-bis-(trifluoromethane)sulfonimide (LiTFSI) is added to the IL. The Li–IL mixture displays ionic conductivity values on the order of 10−4 S cm−1 and an electrochemical stability window in the range of 1.8–4.5 V vs Li+/Li. The voltammetric analysis demonstrates that the cathodic decomposition gives rise to a passivating layer on the surface of the working electrode, which kinetically extends the stability of the Li/IL interface as confirmed by electrochemical impedance spectroscopy measurements. The LiTFSI–PP24TFSI mixture is incorporated in a poly(vinylidene fluoride-co-hexafluoropropylene) matrix to form various electrolyte membranes with different LiTFSI–PP24TFSI contents. The ionic conductivity of all the membranes resembles that of the LiTFSI–IL mixture, suggesting an ionic transport mechanism similar to that of the liquid component. NMR measurements demonstrate a reduction in the mobility of all ions following the addition of LiTFSI to the PP24TFSI IL and when incorporating the mixture into the membrane. Finally, an unexpected but potentially significant enhancement in Li transference number is observed in passing from the liquid to the membrane electrolyte system. PMID:20354582

  17. Synergistic Effects of Mixing Sulfone and Ionic Liquid as Safe Electrolytes for Lithium Sulfur Batteries

    SciTech Connect

    Liao, Chen; Guo, Bingkun; Sun, Xiao-Guang; Dai, Sheng

    2014-11-26

    A strategy of mixing both an ionic liquid and sulfone is reported to give synergistic effects of reducing viscosity, increasing ionic conductivity, reducing polysulfide dissolution, and improving safety. The mixtures of ionic liquids and sulfones also show distinctly different physicochemical properties, including thermal properties and crystallization behavior. By using these electrolytes, lithium sulfur batteries assembled with lithium and mesoporous carbon composites show a reversible specific capacity of 1265 mAhg-1 (second cycle) by using 40% 1.0 M lithium bis(trifluoromethylsulfonyl)imide (LiTFSI) in N-methyl-Npropylpyrrolidinium bis(trifluoromethylsulfonyl)imide with 60% 1.0 M LiTFSI in methylisopropylsulfone in the first cycle. This capacity is slightly lower than that obtained in pure 1.0 M LiTFSI as the sulfone electrolyte; however, it exhibits excellent cycling stability and remains as high as 655 mAhg1 even after 50 cycles. This strategy provides a method to alleviate polysulfide dissolution and redox shuttle phenomena, at the same time, with improved ionic conductivity.

  18. Synergistic Effects of Mixing Sulfone and Ionic Liquid as Safe Electrolytes for Lithium Sulfur Batteries

    DOE PAGES

    Liao, Chen; Guo, Bingkun; Sun, Xiao-Guang; ...

    2014-11-26

    A strategy of mixing both an ionic liquid and sulfone is reported to give synergistic effects of reducing viscosity, increasing ionic conductivity, reducing polysulfide dissolution, and improving safety. The mixtures of ionic liquids and sulfones also show distinctly different physicochemical properties, including thermal properties and crystallization behavior. By using these electrolytes, lithium sulfur batteries assembled with lithium and mesoporous carbon composites show a reversible specific capacity of 1265 mAhg-1 (second cycle) by using 40% 1.0 M lithium bis(trifluoromethylsulfonyl)imide (LiTFSI) in N-methyl-Npropylpyrrolidinium bis(trifluoromethylsulfonyl)imide with 60% 1.0 M LiTFSI in methylisopropylsulfone in the first cycle. This capacity is slightly lower than thatmore » obtained in pure 1.0 M LiTFSI as the sulfone electrolyte; however, it exhibits excellent cycling stability and remains as high as 655 mAhg1 even after 50 cycles. This strategy provides a method to alleviate polysulfide dissolution and redox shuttle phenomena, at the same time, with improved ionic conductivity.« less

  19. Niobium-doped titanium oxide anode and ionic liquid electrolyte for a safe sodium-ion battery

    NASA Astrophysics Data System (ADS)

    Usui, Hiroyuki; Domi, Yasuhiro; Shimizu, Masahiro; Imoto, Akinobu; Yamaguchi, Kazuki; Sakaguchi, Hiroki

    2016-10-01

    The anode properties of Nb-doped rutile TiO2 electrodes were investigated in an ionic liquid electrolyte comprised of N-methyl-N-propylpyrrolidinium cation and bis(fluorosulfonyl)amide anion for use in a safe Na-ion battery. Although the electrolyte's conductivity was lower than that of a conventional organic electrolyte at 30 °C, it showed high conductivity comparable to that of the organic electrolyte at 60 °C. The Nb-doped TiO2 electrode showed excellent cyclability in the ionic liquid electrolyte at 60 °C: a high capacity retention of 97% was observed even at the 350th cycle, which is comparable to value in the organic electrolyte (91%). In a non-flammability test in a closed system, no ignition was observed with the ionic liquid electrolyte even at 300 °C. These results indicate that combination of a Nb-doped TiO2 anode and ionic liquid electrolyte gives not only an excellent cyclability but also high safety for a Na-ion battery operating at a temperature below the sodium's melting point of 98 °C.

  20. Performance of solid state supercapacitors based on polymer electrolytes containing different ionic liquids

    NASA Astrophysics Data System (ADS)

    Tiruye, Girum Ayalneh; Muñoz-Torrero, David; Palma, Jesus; Anderson, Marc; Marcilla, Rebeca

    2016-09-01

    Four Ionic Liquid based Polymer Electrolytes (IL-b-PE) were prepared by blending a Polymeric Ionic Liquid, Poly(diallyldimethylammonium) bis(trifluoromethanesulfonyl)imide (PILTFSI), with four different ionic liquids: 1-butyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide (PYR14TFSI) (IL-b-PE1), 1-butyl-1-methylpyrrolidinium bis(fluorosulfonyl)imide (PYR14FSI) (IL-b-PE2), 1-(2-hydroxy ethyl)-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (HEMimTFSI) (IL-b-PE3), and 1-Butyl-1-methylpyrrolidinium dicyanamide, (PYR14DCA) (IL-b-PE4). Physicochemical properties of IL-b-PE such as ionic conductivity, thermal and electrochemical stability were found to be dependent on the IL properties. For instance, ionic conductivity was significantly higher for IL-b-PE2 and IL-b-PE4 containing IL with small size anions (FSI and DCA) than IL-b-PE1 and IL-b-PE3 bearing IL with bigger anion (TFSI). On the other hand, wider electrochemical stability window (ESW) was found for IL-b-PE1 and IL-b-PE2 having ILs with electrochemically stable pyrrolidinium cation and FSI and TFSI anions. Solid state Supercapacitors (SCs) were assembled with activated carbon electrodes and their electrochemical performance was correlated with the polymer electrolyte properties. Best performance was obtained with SC having IL-b-PE2 that exhibited a good compromise between ionic conductivity and electrochemical window. Specific capacitance (Cam), real energy (Ereal) & real power densities (Preal) as high as 150 F g-1, 36 Wh kg-1 & 1170 W kg-1 were found at operating voltage of 3.5 V.

  1. Electrolytic regeneration of acid cupric chloride printed circuit board etchant. Final report, August 1, 1995--October 31, 1996

    SciTech Connect

    Oxley, J.E.; Smialek, R.J.

    1997-04-18

    The overall objective of this ERIP program was to make substantial progress in further developing a process for electrolytic regeneration of acid cupric chloride etchant - a process which was initially demonstrated in in-house studies and EPA Phase I and Phase II SBIRs. Specific objectives of the work were: (1) to define optimum system operating conditions by conducting a systematic study of process parameters, (2) to develop or find a superior electrolyic cell separator material, (3) to determine an optimum activation procedure for the flow-through carbon/graphite felt electrodes which are so critical to process performance, (4) to demonstrate - on the pre-prototype scale - electrolytic compensation for oxygen ingress - which causes etchant solution growth, and (5) to begin engineering design work on a prototype-scale regeneration unit. Parametric studies looked at the effect that key plating parameters have on copper deposit quality. Parameters tested included (a) velocity past the plating cathodes, (b) copper concentration in the catholyte solution from which the copper is being plated, (c) plating current density, and (d) catholyte cupric ion concentration. The most significant effects were obtained for velocity changes. The work showed that catholyte velocities above 0.5 ft/sec were needed to get adequate plating at 77.5 mA/cm{sup 2} and higher currents, and that even higher flow was better.

  2. Promising Cell Configuration for Next-Generation Energy Storage: Li2S/Graphite Battery Enabled by a Solvate Ionic Liquid Electrolyte.

    PubMed

    Li, Zhe; Zhang, Shiguo; Terada, Shoshi; Ma, Xiaofeng; Ikeda, Kohei; Kamei, Yutaro; Zhang, Ce; Dokko, Kaoru; Watanabe, Masayoshi

    2016-06-29

    Lithium-ion sulfur batteries with a [graphite|solvate ionic liquid electrolyte|lithium sulfide (Li2S)] structure are developed to realize high performance batteries without the issue of lithium anode. Li2S has recently emerged as a promising cathode material, due to its high theoretical specific capacity of 1166 mAh/g and its great potential in the development of lithium-ion sulfur batteries with a lithium-free anode such as graphite. Unfortunately, the electrochemical Li(+) intercalation/deintercalation in graphite is highly electrolyte-selective: whereas the process works well in the carbonate electrolytes inherited from Li-ion batteries, it cannot take place in the ether electrolytes commonly used for Li-S batteries, because the cointercalation of the solvent destroys the crystalline structure of graphite. Thus, only very few studies have focused on graphite-based Li-S full cells. In this work, simple graphite-based Li-S full cells were fabricated employing electrolytes beyond the conventional carbonates, in combination with highly loaded Li2S/graphene composite cathodes (Li2S loading: 2.2 mg/cm(2)). In particular, solvate ionic liquids can act as a single-phase electrolyte simultaneously compatible with both the Li2S cathode and the graphite anode and can further improve the battery performance by suppressing the shuttle effect. Consequently, these lithium-ion sulfur batteries show a stable and reversible charge-discharge behavior, along with a very high Coulombic efficiency.

  3. Influence of the Ionic Liquid Type on the Gel Polymer Electrolytes Properties

    PubMed Central

    Tafur, Juan P.; Santos, Florencio; Fernández Romero, Antonio J.

    2015-01-01

    Gel Polymer Electrolytes (GPEs) composed by ZnTf2 salt, poly(vinylidene fluoride-co-hexafluoropropylene) (PVdF-HFP), and different ionic liquids are synthesized using n-methyl-2-pyrrolidone (NMP) as solvent. Three different imidazolium-based ionic liquids containing diverse cations and anions have been explored. Structural and electrical properties of the GPEs varying the ZnTf2 concentration are analyzed by ATR-FTIR, DSC, TG, and cyclic voltammetry. Free salt IL-GPEs present distinct behavior because they are influenced by the different IL cations and anions composition. However, inclusion of ZnTf2 salt inside the polymers provide GPEs with very similar characteristics, pointing out that ionic transport properties are principally caused by Zn2+ and triflate movement. Whatever the IL used, the presence of NMP solvent inside the polymer’s matrix turns out to be a key factor for improving the Zn2+ transport inside the GPE due to the interaction between Zn2+ cations and carbonyl groups of the NMP. High values of ionic conductivity, low activation energy values, and good voltammetric reversibility obtained regardless of the ionic liquid used enable these GPEs to be applied in Zn batteries. Capacities of 110–120 mAh·g−1 have been obtained for Zn/IL-GPE/MnO2 batteries discharged at −1 mA·cm−2. PMID:26610580

  4. Structural and Dielectric Properties of Ionic Liquid Doped Metal Organic Framework based Polymer Electrolyte Nanocomposites

    NASA Astrophysics Data System (ADS)

    Dutta, Rituraj; Kumar, Ashok

    2016-10-01

    Metal Organic Frameworks (MOFs) are mesoporous materials that can be treated as potential hosts for trapping guest molecules in their pores. Ion conduction and phase behavior dynamics of Ionic Liquids (ILs) can be controlled by tunable interactions of MOFs with the ILs. MOFs incorporated with ionic liquid can be dispersed in the polymers to synthesize polymer electrolyte nanocomposites with high ionic conductivity, electrochemical and thermal stability for applications in energy storage and conversion devices such as rechargeable Li-ion batteries. In the present work we have synthesized Cu-based MOF [Cu3(l,3,5-benzene tricarboxylate)2(H2O)] incorporated with the ionic liquid 1-Butyl-3-methylimidazolium bromide at different weight ratios of MOF and IL. The synthesized MOF-IL composites are dispersed in Poly (ethylene oxide) (PEO). Frequency dependent behavior of permittivity and dielectric loss of the nanocomposites depict the non-Debye dielectric relaxation mechanism. The room temperature Nyquist plots reveal decreasing bulk resistance upto 189 Ω with optimum ionic conductivity of 1.3×10-3S cm-1at maximum doping concentration of IL in the nanocomposite system.

  5. Effects of plasticization on ionic conductivity enhancement of crosslinked polymer electrolyte membrane

    NASA Astrophysics Data System (ADS)

    He, Ruixuan; Kyu, Thein; Kyu's Team, Dr.

    Glass transition temperatures (Tg) of solid polymer electrolyte membranes (PEM), comprised of polyethylene glycol diacrylate (PEGDA) prepolymer, lithium bis(trifluoromethanesulfonyl) imide (LiTFSI) salt, and succinonitrile (SCN) plasticizer, were systematically examined before and after crosslinking in the isotropic region guided by their ternary phase diagram. With increasing LiTFSI concentration, the Tg of uncured binary PEGDA/LiTFSI mixture increases drastically due to molecular complexation between lithium cation and ether oxygen, but ionic conductivity is very low (<10-6 S cm-1). Upon curing, this Tg increases and further reduces ionic conductivity. Upon adding SCN plasticizer, the Tg of PEM has significantly decreased to -60 oC and ionic conductivity also increased to the superionic conductor level of 10-3 S cm-1. The analysis of ionic conductivity vs. Tg behavior by Vogel-Tamman-Fulcher(VTF) equation revealed that this ionic conductivity enhancement is due to SCN plasticization resulting in lowering the network Tg as well as lowering the activation energy. Supported by NSF-DMR 1161070.

  6. Influence of the Ionic Liquid Type on the Gel Polymer Electrolytes Properties.

    PubMed

    Tafur, Juan P; Santos, Florencio; Romero, Antonio J Fernández

    2015-11-19

    Gel Polymer Electrolytes (GPEs) composed by ZnTf₂ salt, poly(vinylidene fluoride-co-hexafluoropropylene) (PVdF-HFP), and different ionic liquids are synthesized using n-methyl-2-pyrrolidone (NMP) as solvent. Three different imidazolium-based ionic liquids containing diverse cations and anions have been explored. Structural and electrical properties of the GPEs varying the ZnTf₂ concentration are analyzed by ATR-FTIR, DSC, TG, and cyclic voltammetry. Free salt IL-GPEs present distinct behavior because they are influenced by the different IL cations and anions composition. However, inclusion of ZnTf₂ salt inside the polymers provide GPEs with very similar characteristics, pointing out that ionic transport properties are principally caused by Zn(2+) and triflate movement. Whatever the IL used, the presence of NMP solvent inside the polymer's matrix turns out to be a key factor for improving the Zn(2+) transport inside the GPE due to the interaction between Zn(2+) cations and carbonyl groups of the NMP. High values of ionic conductivity, low activation energy values, and good voltammetric reversibility obtained regardless of the ionic liquid used enable these GPEs to be applied in Zn batteries. Capacities of 110-120 mAh·g(-1) have been obtained for Zn/IL-GPE/MnO₂ batteries discharged at -1 mA·cm(-2).

  7. Ionomer-Liquid Electrolyte Hybrid Ionic Conductor for High Cycling Stability of Lithium Metal Electrodes

    PubMed Central

    Song, Jongchan; Lee, Hongkyung; Choo, Min-Ju; Park, Jung-Ki; Kim, Hee-Tak

    2015-01-01

    The inhomogeneous Li electrodeposition of lithium metal electrode has been a major impediment to the realization of rechargeable lithium metal batteries. Although single ion conducting ionomers can induce more homogeneous Li electrodeposition by preventing Li+ depletion at Li surface, currently available materials do not allow room-temperature operation due to their low room temperature conductivities. In the paper, we report that a highly conductive ionomer/liquid electrolyte hybrid layer tightly laminated on Li metal electrode can realize stable Li electrodeposition at high current densities up to 10 mA cm−2 and permit room-temperature operation of corresponding Li metal batteries with low polarizations. The hybrid layer is fabricated by laminating few micron-thick Nafion layer on Li metal electrode followed by soaking 1 M LiPF6 EC/DEC (1/1) electrolyte. The Li/Li symmetric cell with the hybrid layer stably operates at a high current density of 10 mA cm−2 for more than 2000 h, which corresponds to more than five-fold enhancement compared with bare Li metal electrode. Also, the prototype Li/LiCoO2 battery with the hybrid layer offers cycling stability more than 350 cycles. These results demonstrate that the hybrid strategy successfully combines the advantages of bi-ionic liquid electrolyte (fast Li+ transport) and single ionic ionomer (prevention of Li+ depletion). PMID:26411701

  8. Biocompatible ionic liquid-biopolymer electrolyte-enabled thin and compact magnesium-air batteries.

    PubMed

    Jia, Xiaoteng; Yang, Yang; Wang, Caiyun; Zhao, Chen; Vijayaraghavan, R; MacFarlane, Douglas R; Forsyth, Maria; Wallace, Gordon G

    2014-12-10

    With the surge of interest in miniaturized implanted medical devices (IMDs), implantable power sources with small dimensions and biocompatibility are in high demand. Implanted battery/supercapacitor devices are commonly packaged within a case that occupies a large volume, making miniaturization difficult. In this study, we demonstrate a polymer electrolyte-enabled biocompatible magnesium-air battery device with a total thickness of approximately 300 μm. It consists of a biocompatible polypyrrole-para(toluene sulfonic acid) cathode and a bioresorbable magnesium alloy anode. The biocompatible electrolyte used is made of choline nitrate (ionic liquid) embedded in a biopolymer, chitosan. This polymer electrolyte is mechanically robust and offers a high ionic conductivity of 8.9 × 10(-3) S cm(-1). The assembled battery delivers a maximum volumetric power density of 3.9 W L(-1), which is sufficient to drive some types of IMDs, such as cardiac pacemakers or biomonitoring systems. This miniaturized, biocompatible magnesium-air battery may pave the way to a future generation of implantable power sources.

  9. Plasmons in Finite Spherical Electrolyte Systems: RPA Effective Jellium Model for Ionic Plasma Excitations.

    PubMed

    Jacak, Witold Aleksander

    Plasmons are fundamental collective excitations in many particle charged systems like in free electron liquid in metals, high energy nuclear plasma in solar core or in fusion devices, in ion gas in ionosphere or in intra- and inter-galactic gas clouds. Plasmons play a central role also in small systems, in particular in metallic nanoparticles and in their arrays allowing for subdiffraction light manipulation. In analogy to metallic nanoparticles, we have developed description of the soft plasmonics in finite electrolyte systems confined in micrometer scale by insulating membranes. Plasmon-type excitations in such finite ionic systems are determined via originally formulated theoretical model allowing to describe surface and volume plasmons in confined geometry of the ion liquid. Size-effect for attenuation of surface plasmons in the finite electrolyte system is described and its various regimes are identified. The cross-over in the plasmon damping system-size-dependence is demonstrated including scattering of ions and their energy losses via irradiation. The plasmon resonances in ion systems replicate the metal cluster plasmon phenomena, though in distinct energy and size scale related to larger ion mass and lower ion concentration (in low energy plasma) in comparison to electrons in metals. The possibility for tuning plasmon resonances in finite ionic systems in a wide range by changing system size, ion, and electrolyte parameters is demonstrated.

  10. High tenacity regenerated chitosan fibers prepared by using the binary ionic liquid solvent (Gly·HCl)-[Bmim]Cl.

    PubMed

    Ma, Bomou; Qin, Aiwen; Li, Xiang; He, Chunju

    2013-09-12

    A binary ionic liquid system was confirmed to be a promising solvent to dissolve chitosan, and the regenerated chitosan fibers were prepared by wet and dry-wet spinning technique respectively. The SEM results show that the chitosan fibers prepared by wet spinning technique present striated surface and round cross section, and the chitosan fibers prepared by dry-wet spinning technique present smooth surface and irregular cross section. The mechanical testing results show that the regenerated chitosan fibers present relatively high tenacity, especially, these prepared by dry-wet spinning process present excellent strength and initial modulus, i.e. 2.1cN/dtex and 83.5cN/dtex, which is stronger than that of most reported chitosan fibers. The FT-IR results show that the dissolution of chitosan in the binary ionic liquid system is due to the protonation of NH₂ groups in the chitosan chains. Furthermore, a possible reaction during the dissolution and regeneration process is proposed.

  11. Ionic liquids in a poly ethylene oxide cross-linked gel polymer as an electrolyte for electrical double layer capacitor

    NASA Astrophysics Data System (ADS)

    Chaudoy, V.; Tran Van, F.; Deschamps, M.; Ghamouss, F.

    2017-02-01

    In the present work, we developed a gel polymer electrolyte via the incorporation of a room temperature ionic liquid into a cross-linked polymer matrix. The cross-linked gel electrolyte was prepared using a free radical polymerization of methacrylate and dimethacrylate oligomers dissolved in 1-propyl-1-methylpyrrolidinium bis(fluorosulfonyl)imide. Combining the advantages of the ionic liquids and of conventional polymers, the cross-linked gel polymer electrolyte was used both as a separator and as an electrolyte for a leakage-free and non-flammable EDLC supercapacitor. The quasi-all solid-state supercapacitors showed rather good capacitance, power and energy densities by comparison to a liquid electrolyte-based EDLC.

  12. Tensile and characterization properties of regenerated cellulose empty fruit bunch biocomposite films using ionic liquid

    NASA Astrophysics Data System (ADS)

    Husseinsyah, Salmah; Zailuddin, Nur Liyana Izyan; Li, Chew Li; Mostapha @ Zakaria, Marliza

    2016-07-01

    The regenerated cellulose (RC) empty fruit bunch (EFB) biocomposite films were prepared using ionic liquid. The tensile strength and modulus of elasticity of regenerated cellulose biocomposite films achieved maximum value at 2 wt% of EFB contents while at 3 and 4 wt% of EFB the tensile strength and modulus of elasticity tend to decreased. The elongation at break tends to decreased at 2 wt% of EFB content but increased at 3 and 4 wt% of EFB contents. The crystallinity index reaches maximum at 2 wt% EFB content, followed by declination with further addition of EFB content. The morphology study illustrated that regenerated cellulose biocomposite films at 2 wt% of EFB contents exhibit a smooth surface that suggested the reinforcement was surrounded by the regenerated cellulose matrix, while at 4 wt% EFB content shows a rough morphology.

  13. Enhanced ionic conductivity with Li7O2Br3 phase in Li3OBr anti-perovskite solid electrolyte

    NASA Astrophysics Data System (ADS)

    Zhu, Jinlong; Li, Shuai; Zhang, Yi; Howard, John W.; Lü, Xujie; Li, Yutao; Wang, Yonggang; Kumar, Ravhi S.; Wang, Liping; Zhao, Yusheng

    2016-09-01

    Cubic anti-perovskites with general formula Li3OX (X = Cl, Br, I) were recently reported as superionic conductors with the potential for use as solid electrolytes in all-solid-state lithium ion batteries. These electrolytes are nonflammable, low-cost, and suitable for thermoplastic processing. However, the primary obstacle of its practical implementation is the relatively low ionic conductivity at room temperature. In this work, we synthesized a composite material consisting of two anti-perovskite phases, namely, cubic Li3OBr and layered Li7O2Br3, by solid state reaction routes. The results indicate that with the phase fraction of Li7O2Br3 increasing to 44 wt. %, the ionic conductivity increased by more than one order of magnitude compared with pure phase Li3OBr. Formation energy calculations revealed the meta-stable nature of Li7O2Br3, which supports the great difficulty in producing phase-pure Li7O2Br3 at ambient pressure. Methods of obtaining phase-pure Li7O2Br3 will continue to be explored, including both high pressure and metathesis techniques.

  14. Enhanced ionic conductivity with Li7O2Br3 phase in Li3OBr anti-perovskite solid electrolyte

    DOE PAGES

    Zhu, Jinlong; Li, Shuai; Zhang, Yi; ...

    2016-09-07

    Cubic anti-perovskites with general formula Li3OX (X = Cl, Br, I) were recently reported as superionic conductors with the potential for use as solid electrolytes in all-solid-state lithium ion batteries. These electrolytes are nonflammable, low-cost, and suitable for thermoplastic processing. However, the primary obstacle of its practical implementation is the relatively low ionic conductivity at room temperature. In this work, we synthesized a composite material consisting of two anti-perovskite phases, namely, cubic Li3OBr and layered Li7O2Br3, by solid state reaction routes. The results indicate that with the phase fraction of Li7O2Br3 increasing to 44 wt. %, the ionic conductivity increasedmore » by more than one order of magnitude compared with pure phase Li3OBr. Formation energy calculations revealed the meta-stable nature of Li7O2Br3, which supports the great difficulty in producing phase-pure Li7O2Br3 at ambient pressure. Here, methods of obtaining phase-pure Li7O2Br3 will continue to be explored, including both high pressure and metathesis techniques.« less

  15. Non-aqueous aluminium-air battery based on ionic liquid electrolyte

    NASA Astrophysics Data System (ADS)

    Revel, Renaud; Audichon, Thomas; Gonzalez, Serge

    2014-12-01

    A promising metal-air secondary battery based on aluminium-oxygen couple is described. In this paper, we observed that an aluminium-air battery employing EMImCl, AlCl3 room temperature ionic liquid (RTIL) as electrolyte and aluminium as negative electrode, has an exceptional reduced self-discharged rate. Due to its new and innovative type of electrolyte, this aluminium-air battery can support relatively high current densities (up to 0.6 mA cm-2) and an average voltage of 0.6-0.8 V. Such batteries may find immediate applications, as they can provide an internal, built-in autonomous and self-sustained energy source.

  16. Lithium bis(fluorosulfonyl)imide-PYR 14TFSI ionic liquid electrolyte compatible with graphite

    NASA Astrophysics Data System (ADS)

    Nádherná, Martina; Reiter, Jakub; Moškon, Jože; Dominko, Robert

    Lithium bis(fluorosulfonyl)imide (LiFSI) in 1-butyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide (PYR 14TFSI) was successfully tested as an electrolyte for graphite composite anodes at elevated temperature of 55 °C. The graphite anode showed a good cyclability during the galvanostatic testing at C/10 rate and 55 °C with the capacity close to theoretical. The formation of SEI in different electrolytes was the subject of study using impedance spectroscopy on symmetrical cells containing two lithium electrodes. The 0.7 m LiFSI in PYR 14TFSI exhibits a good ionic conductivity (5.9 mS cm -1 at 55 °C) along with high electrochemical stability and high thermal stability. These properties allow their potential application in large-scale lithium ion batteries with improved safety.

  17. Azepanium-based ionic liquids as green electrolytes for high voltage supercapacitors

    NASA Astrophysics Data System (ADS)

    Pohlmann, S.; Olyschläger, T.; Goodrich, P.; Alvarez Vicente, J.; Jacquemin, J.; Balducci, A.

    2015-01-01

    This work provides a first-time-study of Azepanium-based ionic liquids (ILs) as electrolyte components for electrochemical double layer capacitors (EDLCs). Herein, two Azepanium-based ILs, namely N-methyl, N-butyl-azepanium bis(trifluoromethanesulfonyl)imide (Azp14TFSI) and N-methyl, N-hexyl-azepanium bis(trifluoromethanesulfonyl)imide (Azp16TFSI) were compared with the established IL N-butyl, N-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide (Pyr14TFSI) in terms of viscosity, conductivity, thermal stability and electrochemical behavior in EDLC systems. The ILs' operative potentials were found to be comparable, leading to operative voltages up to 3.5 V without significant electrolyte degradation.

  18. The Refuelable Zinc-air Battery: Alternative Techniques for Zinc and Electrolyte Regeneration

    SciTech Connect

    Cooper, J F; Krueger, R

    2006-01-19

    An investigation was conducted into alternative techniques for zinc and electrolyte regeneration and reuse in the refuelable zinc/air battery that was developed by LLNL and previously tested on a moving electric bus using cut wire. Mossy zinc was electrodeposited onto a bipolar array of inclined Ni plates with an energy consumption of 1.8 kWh/kg. Using a H{sub 2}-depolarized anode, zinc was deposited at 0.6 V (0.8 kA/m{sup 2}); the open circuit voltage was 0.45 V. Three types of fuel pellets were tested and compared with results for 0.75 mm cut wire: spheres produced in a spouted bed (UCB); coarse powder produced by gas-atomization (Noranda); and irregular pellets produced by chopping 1-mm plates of compacted zinc fines (Eagle-Picher, Inc.). All three types transported within the cell. The coarse powder fed continuously from hopper to cell, as did the compacted pellets (< 0.83 mm). Large particles (> 0.83 mm; Eagle-Picher and UCB) failed to feed from hopper into cell, being held up in the 2.5 mm wide channel connecting hopper to cell. Increasing channel width to {approx}3.5 mm should allow all three types to be used. Energy losses were determined for shorting of cells during refueling. The shorting currents between adjacent hoppers through zinc particle bridges were determined using both coarse powder and chopped compressed zinc plates. A physical model was developed allowing scaling our results for electrode polarization and bed resistance Shorting was found to consume < 0.02% of the capacity of the cell and to dissipate {approx}0.2 W/cell of heat. Corrosion rates were determined for cut wire in contact with current collector materials and battery-produced ZnO-saturated electrolyte. The rates were 1.7% of cell capacity per month at ambient temperatures; and 0.08% of capacity for 12 hours at 57 C. The total energy conversion efficiency for zinc recovery using the hydrogen was estimated at 34% (natural gas to battery terminals)--comparable to fuel cells. Producing

  19. Electrochemical performance of a superporous activated carbon in ionic liquid-based electrolytes

    NASA Astrophysics Data System (ADS)

    Leyva-García, Sarai; Lozano-Castelló, Dolores; Morallón, Emilia; Vogl, Thomas; Schütter, Christoph; Passerini, Stefano; Balducci, Andrea; Cazorla-Amorós, Diego

    2016-12-01

    The electrochemical behaviour of a superporous activated carbon (named as ANK3) with a tailored porosity (high apparent specific surface area and a high volume of micropores with an average pore size of around 1.4 nm) is analysed in different non-aqueous electrolytes. ANK3 shows very high capacitance (higher than 160 F g-1) values in solvent-free electrolytes at different temperatures (20, 40 and 60 °C) as well as in 1 M Et4N BF4/PC, 1 M PYR14 BF4/PC and 1 M PYR14 TFSI/PC. The tailored porosity of the ANK3, makes possible to obtain very high capacitance values, making this superporous activated carbon a promising candidate to be used as electrode for electrochemical capacitors using both organic and ionic liquid electrolytes. It is also confirmed that several parameters, such as the ion/pore size ratio, the ion shape, the ion solvation and the conductivity and viscosity of the electrolyte have a strong influence on the electrochemical behaviour of the ANK3.

  20. Synthesis of Ionic Liquid Based Electrolytes, Assembly of Li-ion Batteries, and Measurements of Performance at High Temperature.

    PubMed

    Lin, Xinrong; Chapman Varela, Jennifer; Grinstaff, Mark W

    2016-12-20

    The chemical instability of the traditional electrolyte remains a safety issue in widely used energy storage devices such as Li-ion batteries. Li-ion batteries for use in devices operating at elevated temperatures require thermally stable and non-flammable electrolytes. Ionic liquids (ILs), which are non-flammable, non-volatile, thermally stable molten salts, are an ideal replacement for flammable and low boiling point organic solvent electrolytes currently used today. We herein describe the procedures to: 1) synthesize mono- and di-phosphonium ionic liquids paired with chloride or bis(trifluoromethane)sulfonimide (TFSI) anions; 2) measure the thermal properties and stability of these ionic liquids by differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA); 3) measure the electrochemical properties of the ionic liquids by cyclic voltammetry (CV); 4) prepare electrolytes containing lithium bis(trifluoromethane)sulfonamide; 5) measure the conductivity of the electrolytes as a function of temperature; 6) assemble a coin cell battery with two of the electrolytes along with a Li metal anode and LiCoO2 cathode; and 7) evaluate battery performance at 100 °C. We additionally describe the challenges in execution as well as the insights gained from performing these experiments.

  1. Graphene-Analogues Boron Nitride Nanosheets Confining Ionic Liquids: A High-Performance Quasi-Liquid Solid Electrolyte.

    PubMed

    Li, Mingtao; Zhu, Wenshuai; Zhang, Pengfei; Chao, Yanhong; He, Qian; Yang, Bolun; Li, Huaming; Borisevich, Albinab; Dai, Sheng

    2016-07-01

    Solid electrolytes are one of the most promising electrolyte systems for safe lithium batteries, but the low ionic conductivity of these electrolytes seriously hinders the development of efficient lithium batteries. Here, a novel class of graphene-analogues boron nitride (g-BN) nanosheets confining an ultrahigh concentration of ionic liquids (ILs) in an interlayer and out-of-layer chamber to give rise to a quasi-liquid solid electrolyte (QLSE) is reported. The electron-insulated g-BN nanosheet host with a large specific surface area can confine ILs as much as 10 times of the host's weight to afford high ionic conductivity (3.85 × 10(-3) S cm(-1) at 25 °C, even 2.32 × 10(-4) S cm(-1) at -20 °C), which is close to that of the corresponding bulk IL electrolytes. The high ionic conductivity of QLSE is attributed to the enormous absorption for ILs and the confining effect of g-BN to form the ordered lithium ion transport channels in an interlayer and out-of-layer of g-BN. Furthermore, the electrolyte displays outstanding electrochemical properties and battery performance. In principle, this work enables a wider tunability, further opening up a new field for the fabrication of the next-generation QLSE based on layered nanomaterials in energy conversion devices.

  2. Capacitive Energy Storage from - 50o to 100o Using an Ionic Liquid Electrolyte

    SciTech Connect

    Lin, Rongying; Taberna, Pierre-Louis; Santini, Sebastien; Presser, Volker; Perez, Carlos R.; Malbosc, Francois; Rupesinghe, Nalin L.; Teo, Kenneth B. K.; Gogotsi, Yury G.; Simon, Patrice

    2011-01-01

    Relying on redox reactions, most batteries are limited in their ability to operate at very low or very high temperatures. While performance of electrochemical capacitors is less dependent on the temperature, present-day devices still cannot cover the entire range needed for automotive and electronics applications under a variety of environmental conditions. We show that the right combination of the exohedral nanostructured carbon (nanotubes and onions) electrode and a eutectic mixture of ionic liquids can dramatically extend the temperature range of electrical energy storage, thus defying the conventional wisdom that ionic liquids can only be used as electrolytes above room temperature. We demonstrate electrical double layer capacitors able to operate from 50 to 100 C over a wide voltage window (up to 3.7 V) and at very high charge/discharge rates of up to 20 V/s.

  3. Ion beam irradiation as a tool to improve the ionic conductivity in solid polymer electrolyte systems

    NASA Astrophysics Data System (ADS)

    Manjunatha, H.; Damle, R.; Kumaraswamy, G. N.

    2016-05-01

    Solid polymer electrolytes (SPEs) have potential applications in solid state electronic and energy devices. The optimum conductivity of SPEs required for such applications is about 10-1 - 10-3 Scm-1, which is hard to achieve in these systems. It is observed that ionic conductivity of SPEs continuously increase with increasing concentration of inorganic salt in the host polymer. However, there is a critical concentration of the salt beyond which the conductivity of SPEs decreases due to the formation of ion pairs. In the present study, solid polymer thin films based on poly (ethylene oxide) (PEO) complexed with NaBr salt with different concentrations have been prepared and the concentration at which ion pair formation occurs in PEOxNaBr is identified. The microstructure of the SPE with highest ionic conductivity is modified by irradiating it with low energy O+1 ion (100 keV) of different fluencies. It is observed that the ionic conductivity of irradiated SPEs increases by one order in magnitude. The increase in ionic conductivity may be attributed to the enhanced segmental motion of the polymer chains due to radiation induced micro structural modification.

  4. Structure and mechanisms underlying ion transport in ternary polymer electrolytes containing ionic liquids

    NASA Astrophysics Data System (ADS)

    Mogurampelly, Santosh; Ganesan, Venkat

    2017-02-01

    We use all atom molecular dynamics simulations to investigate the influence of 1-butyl-3-methylimidazolium hexafluorophosphate (BMIMPF6) ionic liquid on the structure and transport properties of poly(ethylene oxide) (PEO) polymer electrolytes doped with LiPF6 salt. We observe enhanced diffusivities of the Li+, PF6-, and BMIM+ ions with increasing loading of the ionic liquid. Interplay between the different ion-ion and ion-polymer interactions is seen to lead to a destabilization of the Li-PF6 coordination and increase in the strength of association between the Li+ cations and the polymer backbone. As a consequence, the polymer segmental relaxation times are shown to be only moderately affected by the addition of ionic liquids. The ionic-liquid induced changes in the mobilities of Li+ ions are seen to be correlated to polymer segmental relaxation times. However, the mobilities of BMIM+ ions are seen to be more strongly correlated to the BMIM-PF6 ion-pair relaxation times.

  5. Ionic liquid-based green processes for energy production.

    PubMed

    Zhang, Suojiang; Sun, Jian; Zhang, Xiaochun; Xin, Jiayu; Miao, Qingqing; Wang, Jianji

    2014-11-21

    To mitigate the growing pressure on resource depletion and environment degradation, the development of green processes for the production of renewable energy is highly required. As a class of novel and promising media, ionic liquids (ILs) have shown infusive potential applications in energy production. Aiming to offer a critical overview regarding the new challenges and opportunities of ILs for developing green processes of renewable energy, this article emphasises the role of ILs as catalysts, solvents, or electrolytes in three broadly interesting energy production processes from renewable resources, such as CO2 conversion to fuels and fuel additives, biomass pretreatment and conversion to biofuels, as well as solar energy and energy storage. It is expected that this article will stimulate a generation of new ideas and new technologies in IL-based renewable energy production.

  6. Robust High-performance Dye-sensitized Solar Cells Based on Ionic Liquid-sulfolane Composite Electrolytes

    PubMed Central

    Lau, Genevieve P. S.; Décoppet, Jean-David; Moehl, Thomas; Zakeeruddin, Shaik M.; Grätzel, Michael; Dyson, Paul J.

    2015-01-01

    Novel ionic liquid-sulfolane composite electrolytes based on the 1,2,3-triazolium family of ionic liquids were developed for dye-sensitized solar cells. The best performing device exhibited a short-circuit current density of 13.4 mA cm−2, an open-circuit voltage of 713 mV and a fill factor of 0.65, corresponding to an overall power conversion efficiency (PCE) of 6.3%. In addition, these devices are highly stable, retaining more than 95% of the initial device PCE after 1000 hours of light- and heat-stress. These composite electrolytes show great promise for industrial application as they allow for a 14.5% improvement in PCE, compared to the solvent-free eutectic ionic liquid electrolyte system, without compromising device stability. PMID:26670595

  7. A mean-field theory on the differential capacitance of asymmetric ionic liquid electrolytes.

    PubMed

    Han, Yining; Huang, Shanghui; Yan, Tianying

    2014-07-16

    The size of ions significantly influences the electric double layer structure of room temperature ionic liquid (IL) electrolytes and their differential capacitance (Cd). In this study, we extended the mean-field theory (MFT) developed independently by Kornyshev (2007J. Phys. Chem. B 111 5545-57) and Kilic, Bazant, and Ajdari (2007 Phys. Rev. E 75 021502) (the KKBA MFT) to take into account the asymmetric 1:1 IL electrolytes by introducing an additional parameter ξ for the anion/cation volume ratio, besides the ionic compressibility γ in the KKBA MFT. The MFT of asymmetric ions becomes KKBA MFT upon ξ = 1, and further reduces to Gouy-Chapman theory in the γ → 0 limit. The result of the extended MFT demonstrates that the asymmetric ILs give rise to an asymmetric Cd, with the higher peak in Cd occurring at positive polarization for the smaller anionic size. At high potential, Cd decays asymptotically toward KKBA MFT characterized by γ for the negative polarization, and characterized by ξγ for the positive polarization, with inverse-square-root behavior. At low potential, around the potential of zero charge, the asymmetric ions cause a higher Cd, which exceeds that of Gouy-Chapman theory.

  8. Novel polymer electrolytes based on thermoplastic polyurethane and ionic liquid/lithium bis(trifluoromethanesulfonyl)imide/propylene carbonate salt system

    NASA Astrophysics Data System (ADS)

    Lavall, R. L.; Ferrari, S.; Tomasi, C.; Marzantowicz, M.; Quartarone, E.; Magistris, A.; Mustarelli, P.; Lazzaroni, S.; Fagnoni, M.

    Polymer electrolytes were prepared from thermoplastic polyurethane with addition of mixture of ionic liquid N-ethyl(methylether)-N-methylpyrrolidinium trifluoromethanesulfonimmide (PYRA 12O1TFSI), lithium bis(trifluoromethanesulfoneimide) salt and propylene carbonate. The electrolytes characterization was performed by thermogravimetric analysis, differential scanning calorimetry and scanning electron microscopy. The electrical properties were investigated in detail by impedance spectroscopy with the aid of equivalent circuit fitting of the impedance spectra. A model describing temperature evolution of ionic conductivity and the properties of electrolyte/blocking electrode interface was developed. The electrochemical stability of the electrolytes was studied by linear voltammetry. Our results indicate that the studied electrolytes have good self-standing characteristics, and also a sufficient level of thermal stability and a fairly good electrochemical window. The ionic conductivity increases with increasing amount of mixture, and the character of temperature dependence of conductivity indicates decoupling of ion transport from polymer matrix. For studied system, the highest value of ionic conductivity measured at room temperature was 10 -4 S cm -1.

  9. Ionic Liquid Hybrid Electrolytes for Lithium-Ion Batteries: A Key Role of the Separator-Electrolyte Interface in Battery Electrochemistry.

    PubMed

    Huie, Matthew M; DiLeo, Roberta A; Marschilok, Amy C; Takeuchi, Kenneth J; Takeuchi, Esther S

    2015-06-10

    Batteries are multicomponent systems where the theoretical voltage and stoichiometric electron transfer are defined by the electrochemically active anode and cathode materials. While the electrolyte may not be considered in stoichiometric electron-transfer calculations, it can be a critical factor determining the deliverable energy content of a battery, depending also on the use conditions. The development of ionic liquid (IL)-based electrolytes has been a research area of recent reports by other researchers, due, in part, to opportunities for an expanded high-voltage operating window and improved safety through the reduction of flammable solvent content. The study reported here encompasses a systematic investigation of the physical properties of IL-based hybrid electrolytes including quantitative characterization of the electrolyte-separator interface via contact-angle measurements. An inverse trend in the conductivity and wetting properties was observed for a series of IL-based electrolyte candidates. Test-cell measurements were undertaken to evaluate the electrolyte performance in the presence of functioning anode and cathode materials, where several promising IL-based hybrid electrolytes with performance comparable to that of conventional carbonate electrolytes were identified. The study revealed that the contact angle influenced the performance more significantly than the conductivity because the cells containing IL-tetrafluoroborate-based electrolytes with higher conductivity but poorer wetting showed significantly decreased performance relative to the cells containing IL-bis(trifluoromethanesulfonyl)imide electrolytes with lower conductivity but improved wetting properties. This work contributes to the development of new IL battery-based electrolyte systems with the potential to improve the deliverable energy content as well as safety of lithium-ion battery systems.

  10. Ionic conductivity and dielectric permittivity of PEO-LiClO{sub 4} solid polymer electrolyte plasticized with propylene carbonate

    SciTech Connect

    Das, S.; Ghosh, A.

    2015-02-15

    We have studied ionic conductivity and dielectric permittivity of PEO-LiClO{sub 4} solid polymer electrolyte plasticized with propylene carbonate. Differential scanning calorimetry and X-ray diffraction studies confirm minimum volume fraction of crystalline phase for the polymer electrolyte with 40 wt. % propylene carbonate. The ionic conductivity exhibits a maximum for the same composition. The temperature dependence of the ionic conductivity has been well interpreted using Vogel-Tamman-Fulcher equation. Ion-ion interactions in the polymer electrolytes have been studied using Raman spectra and the concentrations of free ions, ion-pairs and ion-aggregates have been determined. The ionic conductivity increases due to the increase of free ions with the increase of propylene carbonate content. But for higher content of propylene carbonate, the ionic conductivity decreases due to the increase of concentrations of ion-pairs and ion-aggregates. To get further insights into the ion dynamics, the experimental data for the complex dielectric permittivity have been studied using Havriliak–Negami function. The variation of relaxation time with temperature obtained from this formalism follows Vogel-Tamman-Fulcher equation similar to the ionic conductivity.

  11. "Ionic liquids-in-salt"--a promising electrolyte concept for high-temperature lithium batteries?

    PubMed

    Marczewski, Maciej J; Stanje, Bernhard; Hanzu, Ilie; Wilkening, Martin; Johansson, Patrik

    2014-06-28

    A novel electrolyte concept for lithium-ion batteries, termed "ionic liquid-in-salt", is introduced. Our feasibility study on (1 - x)EMIMTFSI:(x)LiTFSI, 0.66 ≤ x ≤ 0.97, showed that at elevated temperatures the various dual liquid and solid phase regions are characterized by a wide thermal stability window, high ionic conductivities and appreciable mechanical integrity. The highest conductivity values are obtained for the compositions x = 0.70 and x = 0.75 (σ ≈ 6 × 10(-3) S cm(-1)) and are related to the final melting of the materials. Overall, high conductivities are observed for 0.70 < x < 0.90 while low ones are found for x > 0.90. Raman and NMR spectroscopies reveal the presence of highly mobile Li-containing species, partly identified as [Li(TFSI)2](-), albeit rather unexpected for these high x values, which might explain the high ionic conductivities observed. To prove the general value of our concept in more detail, some first results on BMIMTFSI and PY13TFSI based systems are also presented.

  12. Highly efficient solid-state dye-sensitized solar cells based on hexylimidazolium iodide ionic polymer electrolyte prepared by in situ low-temperature polymerization

    NASA Astrophysics Data System (ADS)

    Wang, Guiqiang; Yan, Chao; Zhang, Juan; Hou, Shuo; Zhang, Wei

    2017-03-01

    Solid-state dye-sensitized solar cells (DSCs) are fabricated using a novel ionic polymer electrolyte containing hexylimidazolium iodide (HII) ionic polymer prepared by in situ polymerization of N,N‧-bis(imidazolyl) hexane and 1,6-diiodohexane without an initiator at low temperature (40 °C). The as-prepared HII ionic polymer has a similar structure to alkylimidazolium iodide ionic liquid, and the imidazolium cations are contained in the polymer main chain; so, it can act simultaneously as the redox mediator in the electrolyte. By incorporating an appropriate amount of 1,3-dimethylimidazolium iodide (DMII) in HII ionic polymer (DMII/HII ionic polymer = 0.7:1, weight ratio), the conductivity of the ionic polymer electrolyte is greatly improved due to the formation of Grotthuss bond exchange. In addition, in situ synthesis of ionic polymer electrolyte guarantees a good pore-filling of the electrolyte in the TiO2 photoanode. As a result, the solid-state DSC based on the ionic polymer electrolyte containing HII ionic polymer and DMII without iodine achieves a conversion efficiency of 6.55% under the illumination of 100 mW cm-2 (AM 1.5), which also exhibits a good at-rest stability at room temperature.

  13. Graphene-based supercapacitors in the parallel-plate electrode configuration: ionic liquids versus organic electrolytes.

    PubMed

    Shim, Youngseon; Kim, Hyung J; Jung, Younjoon

    2012-01-01

    Supercapacitors with two single-sheet graphene electrodes in the parallel plate geometry are studied via molecular dynamics (MD) computer simulations. Pure 1-ethyl-3-methylimidazolium tetrafluoroborate (EMI+BF4-) and a 1.1 M solution of EMI+BF4- in acetonitrile are considered as prototypes of room-temperature ionic liquids (RTILs) and organic electrolytes. Electrolyte structure, charge density and associated electric potential are investigated by varying the charges and separation of the two electrodes. Multiple charge layers formed in the electrolytes in the vicinity of the electrodes are found to screen the electrode surface charge almost completely. As a result, the supercapacitors show nearly an ideal electric double layer behavior, i.e., the electric potential exhibits essentially a plateau behavior in the entire electrolyte region except for sharp changes in screening zones very close to the electrodes. Due to its small size and large charge separation, BF4- is considerably more efficient in shielding electrode charges than EMI+. In the case of the acetonitrile solution, acetonitrile also plays an important role by aligning its dipoles near the electrodes; however, the overall screening mainly arises from ions. Because of the disparity of shielding efficiency between cations and anions, the capacitance of the positively-charged anode is significantly larger than that of the negatively-charged cathode. Therefore, the total cell capacitance in the parallel plate configuration is primarily governed by the cathode. Ion conductivity obtained via the Green-Kubo (GK) method is found to be largely independent of the electrode surface charge. Interestingly, EMI+BF4- shows higher GK ion conductivity than the 1.1 M acetonitrile solution between two parallel plate electrodes.

  14. Comparative investigation of underpotential deposition of Ag from aqueous and ionic electrolytes: An electrochemical and in situ STM study.

    PubMed

    Borissov, D; Aravinda, C L; Freyland, W

    2005-06-16

    Underpotential deposition (UPD) of Ag on Au(111) has been studied with two different electrolytes: aqueous 0.1 M H2SO4 solution in comparison with the ionic liquid 1-butyl-3-methylimidazolium chloride BMICl + AlCl3. Of particular interest is the distinct behavior of 2D phase formation at both interfaces, which has been investigated by cyclic and linear sweep voltammetry in combination with in situ electrochemical scanning tunneling microscopy (STM). It is found that one monolayer (ML) of Ag is formed in the UPD region in both electrolytes. In aqueous solution, atomically resolved STM images at 500 mV versus Ag/Ag+ show a (3 x 3) adlayer of Ag, whereas after sweeping the potential just before the commencement of the bulk Ag deposition, a transition from expanded (3 x 3) to pseudomorphic ML of Ag on Au(111) occurs. In BMICl-AlCl3, the first UPD process of Ag exhibits two peaks at 410 and 230 mV indicating that two distinct processes on the surface take place. For the first time, STM images with atomic resolution reveal a transition from an inhomogeneous to an ordered phase with a (square root of 3 x square root of 3)R30 degrees structure and an adsorption of AlCl4- anions having a superlattice of (1.65 x square root of 3)R30 degrees preceding the deposition of Ag.

  15. Ionic Liquid-Based Polymer Electrolytes via Surfactant-Assisted Polymerization at the Plasma-Liquid Interface.

    PubMed

    Tran, Quoc Chinh; Bui, Van-Tien; Dao, Van-Duong; Lee, Joong-Kee; Choi, Ho-Suk

    2016-06-29

    We first report an innovative method, which we refer to as interfacial liquid plasma polymerization, to chemically cross-link ionic liquids (ILs). By this method, a series of all-solid state, free-standing polymer electrolytes is successfully fabricated where ILs are used as building blocks and ethylene oxide-based surfactants are employed as an assisted-cross-linking agent. The thickness of the films is controlled by the plasma exposure time or the ratio of surfactant to ILs. The chemical structure and properties of the polymer electrolyte are characterized by scanning electron microscopy (SEM), Fourier transformation infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR) spectroscopy, X-ray photoelectron spectroscopy (XPS), differential scanning calorimetry (DSC), and electrochemical impedance spectroscopy (EIS). Importantly, the underlying polymerization mechanism of the cross-linked IL-based polymer electrolyte is studied to show that fluoroborate or halide anions of ILs together with the aid of a small amount of surfactants having ethylene oxide groups are necessary to form cross-linked network structures of the polymer electrolyte. The ionic conductivity of the obtained polymer electrolyte is 2.28 × 10(-3) S·cm(-1), which is a relatively high value for solid polymer electrolytes synthesized at room temperature. This study can serve as a cornerstone for developing all-solid state polymer electrolytes with promising properties for next-generation electrochemical devices.

  16. Influence of Al2O3 on the ionic conductivity of plasticized PVC-PEG blend polymer electrolytes

    NASA Astrophysics Data System (ADS)

    Ravindran, D.; Vickraman, P.

    2016-05-01

    Polymer electrolytes with PVC-PEG blend as host matrix and LiClO4 as dopant salt was prepared through conventional solution casting method. To enhance the conductivity propylene carbonate (PC) was used as plasticizer. The influence of ceramic filler Al2O3 on the conductivity of the electrolyte films were studied by varying the (PVC: Al2O3) ratio. The films were subjected to XRD, complex impedance analysis and SEM analysis. The XRD studies reveal a marginal increase in the amorphous phase of the electrolyte films due to the incorporation of filler. The AC impedance analysis shows the dependency of ionic conductivity on the content (wt %) of filler and exhibit a maximum at 4 wt% filler. The SEM analysis depicts the occurrence of phase separation in electrolyte which is attributed to the poor solubility of polymer PVC in the liquid electrolyte.

  17. Life Support Catalyst Regeneration Using Ionic Liquids and In Situ Resources

    NASA Technical Reports Server (NTRS)

    Abney, Morgan B.; Karr, Laurel; Paley, Mark S.; Donovan, David N.

    2016-01-01

    Oxygen recovery from metabolic carbon dioxide is an enabling capability for long-duration manned space flight. Complete recovery of oxygen (100%) involves the production of solid carbon. Catalytic approaches for this purpose, such as Bosch technology, have been limited in trade analyses due in part to the mass penalty for high catalyst resupply caused by carbon fouling of the iron or nickel catalyst. In an effort to mitigate this challenge, several technology approaches have been proposed. These approaches have included methods to prolong the life of the catalysts by increasing the total carbon mass loading per mass catalyst, methods for simplified catalyst introduction and removal to limit the resupply container mass, methods of using in situ resources, and methods to regenerate catalyst material. Research and development into these methods is ongoing, but only use of in situ resources and/or complete regeneration of catalyst material has the potential to entirely eliminate the need for resupply. The use of ionic liquids provides an opportunity to combine these methods in a technology approach designed to eliminate the need for resupply of oxygen recovery catalyst. Here we describe the results of an initial feasibility study using ionic liquids and in situ resources for life support catalyst regeneration, we discuss the key challenges with the approach, and we propose future efforts to advance the technology.

  18. Anionic structure-dependent photoelectrochemical responses of dye-sensitized solar cells based on a binary ionic liquid electrolyte.

    PubMed

    Hao, Feng; Lin, Hong; Liu, Yizhu; Li, Jianbao

    2011-04-14

    Room temperature ionic liquids (RTILs) have been used as electrolytes to investigate the anionic structure dependence of the photoelectrochemical responses of dye-sensitized solar cells (DSCs). A series of RTILs with a fixed cation structure coupling with various anion structures are employed, in which 1-methyl-3-propylimidazolium iodide (PMII) and I(2) are dissolved as redox couples. It is found that both the diffusivity of the electrolyte and the photovoltaic performance of the device show a strong dependence on the fluidity of the ionic liquids, which is primarily altered by the anion structure. Further insights into the structure-dependent physical properties of the employed RTILs are discussed in terms of the reported van der Waals radius, the atomic charge distribution over the anion backbones, the interaction energy of the anion and cation, together with the existence of ion-pairs and ion aggregates. Particularly, both the short-circuit photocurrent and open-circuit voltage exhibit obvious fluidity dependence. Electrochemical impedance and intensity-modulated photovoltage/photocurrent spectroscopy analysis further reveal that increasing the fluidity of the ionic liquid electrolytes could significantly decrease the diffusion resistance of I(3)(-) in the electrolyte, and retard the charge recombination between the injected electrons with triiodide in the high-viscous electrolyte, thus improving the electron diffusion length in the device, as well as the photovoltaic response. However, the variation of the electron diffusion coefficients is trivial primarily due to the effective charge screening of the high cation concentration.

  19. Catalyst regeneration process including metal contaminants removal

    DOEpatents

    Ganguli, Partha S.

    1984-01-01

    Spent catalysts removed from a catalytic hydrogenation process for hydrocarbon feedstocks, and containing undesired metals contaminants deposits, are regenerated. Following solvent washing to remove process oils, the catalyst is treated either with chemicals which form sulfate or oxysulfate compounds with the metals contaminants, or with acids which remove the metal contaminants, such as 5-50 W % sulfuric acid in aqueous solution and 0-10 W % ammonium ion solutions to substantially remove the metals deposits. The acid treating occurs within the temperature range of 60.degree.-250.degree. F. for 5-120 minutes at substantially atmospheric pressure. Carbon deposits are removed from the treated catalyst by carbon burnoff at 800.degree.-900.degree. F. temperature, using 1-6 V % oxygen in an inert gas mixture, after which the regenerated catalyst can be effectively reused in the catalytic process.

  20. A molecular dynamics simulation study of LiFePO4/electrolyte interfaces: structure and Li+ transport in carbonate and ionic liquid electrolytes.

    PubMed

    Smith, Grant D; Borodin, Oleg; Russo, Salvy P; Rees, Robert J; Hollenkamp, Anthony F

    2009-11-14

    We have performed atomistic molecular dynamics (MD) simulations of the (010) surface of LiFePO(4) in contact with an organic liquid electrolyte (OLE), ethylene carbonate : dimethyl carbonate (3 : 7) with approximately 1 mol kg(-1) LiPF(6), and an ionic liquid-based electrolyte (ILE), 1-ethyl 3-methyl-imidazolium: bis(fluorosulfonyl)imide (EMIM(+) : FSI(-)) with approximately 1 mol kg(-1) LiFSI. Surface-induced structure that extends about 1 nm from the LiFePO(4) surface was observed in both electrolytes. The electrostatic potential at the LiFePO(4) surface was found to be negative relative to the bulk electrolyte reflecting an excess of negative charge from the electrolyte coordinating surface Li(+). In the ILE system negative surface charge is partially offset by a high density of EMIM(+) cations coordinating surface oxygen. The electrostatic potential exhibits a (positive) maximum about 3 A from the LiFePO(4) surface which, when combined with the reduced ability of the highly structured electrolytes to solvate Li(+) cations, results in a free energy barrier of almost 4 kcal mol(-1) for penetration of the interfacial electrolyte layer by Li(+). The resistance for bringing Li(+) from the bulk electrolyte to the LiFePO(4) surface through this interfacial barrier was found to be small for both the OLE and ILE. However, we find that the ability of EMIM(+) cations to donate positive charge to LiFePO(4)/electrolyte interface may result in a significant decrease in the concentration of Li(+) at the surface and a corresponding increase in impedance to Li(+) intercalation into LiFePO(4), particularly at lower temperatures.

  1. Bis(fluoromalonato)borate (BFMB) Anion Based Ionic Liquid As an Additive for Lithium-Ion Battery Electrolytes

    SciTech Connect

    Sun, Xiao-Guang; Liao, Chen; Baggetto, Loic; Guo, Bingkun; Unocic, Raymond R; Veith, Gabriel M; Dai, Sheng

    2014-01-01

    Propylene carbonate (PC) is a good solvent for lithium ion battery applications due to its low melting point and high dielectric constant. However, PC is easily intercalated into graphite causing it to exfoliate, killing its electrochemical performance. Here we report on the synthesis of a new ionic liquid electrolyte based on partially fluorinated borate anion, 1-butyl-1,2-dimethylimidazolium bis(fluoromalonato)borate (BDMIm.BFMB), which can be used as an additive in 1 M LiPF6/PC electrolyte to suppress graphite exfoliation and improve cycling performance. In addition, both PC and BDMIm.BFMB can be used synergistically as additive to 1.0M LiPF6/methyl isopropyl sulfone (MIPS) to dramatically improve its cycling performance. It is also found that the chemistry nature of the ionic liquids has dramatic effect on their role as additive in PC based electrolyte.

  2. Analysis of cell performance and thermal regeneration of a lithium-tin cell having an immobilized fused-salt electrolyte

    NASA Technical Reports Server (NTRS)

    Cairns, E. J.; Shimotake, H.

    1969-01-01

    Cell performance and thermal regeneration of a thermally regenerative cell uses lithium and tin and a fused-salt electrolyte. The emf of the Li-Sn cell, as a function of cathode-alloy composition, is shown to resemble that of the Na-Bi cell.

  3. Electrochemical energy storage in montmorillonite K10 clay based composite as supercapacitor using ionic liquid electrolyte.

    PubMed

    Maiti, Sandipan; Pramanik, Atin; Chattopadhyay, Shreyasi; De, Goutam; Mahanty, Sourindra

    2016-02-15

    Exploring new electrode materials is the key to realize high performance energy storage devices for effective utilization of renewable energy. Natural clays with layered structure and high surface area are prospective materials for electrical double layer capacitors (EDLC). In this work, a novel hybrid composite based on acid-leached montmorillonite (K10), multi-walled carbon nanotube (MWCNT) and manganese dioxide (MnO2) was prepared and its electrochemical properties were investigated by fabricating two-electrode asymmetric supercapacitor cells against activated carbon (AC) using 1.0M tetraethylammonium tetrafluroborate (Et4NBF4) in acetonitrile (AN) as electrolyte. The asymmetric supercapacitors, capable of operating in a wide potential window of 0.0-2.7V, showed a high energy density of 171Whkg(-1) at a power density of ∼1.98kWkg(-1). Such high EDLC performance could possibly be linked to the acid-base interaction of K10 through its surface hydroxyl groups with the tetraethylammonium cation [(C2H5)4N(+) or TEA(+)] of the ionic liquid electrolyte. Even at a very high power density of 96.4kWkg(-1), the cells could still deliver an energy density of 91.1Whkg(-1) exhibiting an outstanding rate capability. The present study demonstrates for the first time, the excellent potential of clay-based composites for high power energy storage device applications.

  4. Effect of Non-ionic Surfactants and Its Role in K Intercalation in Electrolytic Manganese Dioxide

    NASA Astrophysics Data System (ADS)

    Biswal, Avijit; Tripathy, B. C.; Subbaiah, T.; Meyrick, D.; Ionescu, Mihail; Minakshi, Manickam

    2014-09-01

    The effect of non-ionic surface active agents (surfactants) Triton X-100 (TX-100) and Tween-20 (Tw-20) and their role in potassium intercalation in electrolytic manganese dioxide (EMD) produced from manganese cake has been investigated. Electrosynthesis of MnO2 in the absence or presence of surfactant was carried out from acidic MnSO4 solution obtained from manganese cake under optimized conditions. A range of characterization techniques, including field emission scanning electron microscopy, transmission electron microscopy (TEM), Rutherford back scattering (RBS), and BET surface area/porosity studies, was carried out to determine the structural and chemical characteristics of the EMD. Galvanostatic (discharge) and potentiostatic (cyclic voltammetric) studies were employed to evaluate the suitability of EMD in combination with KOH electrolyte for alkaline battery applications. The presence of surfactant played an important role in modifying the physicochemical properties of the EMD by increasing the surface area of the material and hence, enhancing its electrochemical performance. The TEM and RBS analyses of the discharged EMD (γ-MnO2) material showed clear evidence of potassium intercalation or at least the formation of a film on the MnO2 surface. The extent of intercalation was greater for EMD deposited in the presence of TX-100. Discharged MnO2 showed products of Mn2+ intermediates such as MnOOH and Mn3O4.

  5. Effects of ionic liquids on cation dynamics in amorphous polyethylene oxide electrolytes

    SciTech Connect

    Chattoraj, Joyjit Diddens, Diddo; Heuer, Andreas

    2014-01-14

    We perform extensive molecular dynamics simulations of a poly(ethylene oxide)-based polymer electrolyte material containing lithium bis(trifluoromethanesulfonyl)imide salt for a wide temperature regime above and below the experimental crystallization temperature with and without N-methyl-N-propylpyrrolidinium bis(trifluoromethanesulfonyl)imide ionic liquid (IL). The impact of the IL-concentration on the cation dynamics is studied. The increase of the cation mobility upon addition of IL is significant but temperature-independent. This can be related to distinct variations of the underlying transport properties as expressed within the previously introduced transport model of polymer electrolytes. Even for the largest IL concentration the transport model perfectly predicts the non-trivial time-dependence of the cationic mean square displacement for all temperatures. Finally, we compare our numerical and theoretical findings with the results of recent nuclear magnetic resonance experiments. In this way we can exclusively relate the strong experimentally observed dependence of the low-temperature Li-diffusivity on the IL concentration to the impact of IL on crystallization.

  6. Effects of ionic liquids on cation dynamics in amorphous polyethylene oxide electrolytes.

    PubMed

    Chattoraj, Joyjit; Diddens, Diddo; Heuer, Andreas

    2014-01-14

    We perform extensive molecular dynamics simulations of a poly(ethylene oxide)-based polymer electrolyte material containing lithium bis(trifluoromethanesulfonyl)imide salt for a wide temperature regime above and below the experimental crystallization temperature with and without N-methyl-N-propylpyrrolidinium bis(trifluoromethanesulfonyl)imide ionic liquid (IL). The impact of the IL-concentration on the cation dynamics is studied. The increase of the cation mobility upon addition of IL is significant but temperature-independent. This can be related to distinct variations of the underlying transport properties as expressed within the previously introduced transport model of polymer electrolytes. Even for the largest IL concentration the transport model perfectly predicts the non-trivial time-dependence of the cationic mean square displacement for all temperatures. Finally, we compare our numerical and theoretical findings with the results of recent nuclear magnetic resonance experiments. In this way we can exclusively relate the strong experimentally observed dependence of the low-temperature Li-diffusivity on the IL concentration to the impact of IL on crystallization.

  7. Effects of ionic liquids on cation dynamics in amorphous polyethylene oxide electrolytes

    NASA Astrophysics Data System (ADS)

    Chattoraj, Joyjit; Diddens, Diddo; Heuer, Andreas

    2014-01-01

    We perform extensive molecular dynamics simulations of a poly(ethylene oxide)-based polymer electrolyte material containing lithium bis(trifluoromethanesulfonyl)imide salt for a wide temperature regime above and below the experimental crystallization temperature with and without N-methyl-N-propylpyrrolidinium bis(trifluoromethanesulfonyl)imide ionic liquid (IL). The impact of the IL-concentration on the cation dynamics is studied. The increase of the cation mobility upon addition of IL is significant but temperature-independent. This can be related to distinct variations of the underlying transport properties as expressed within the previously introduced transport model of polymer electrolytes. Even for the largest IL concentration the transport model perfectly predicts the non-trivial time-dependence of the cationic mean square displacement for all temperatures. Finally, we compare our numerical and theoretical findings with the results of recent nuclear magnetic resonance experiments. In this way we can exclusively relate the strong experimentally observed dependence of the low-temperature Li-diffusivity on the IL concentration to the impact of IL on crystallization.

  8. Characterization of conducting cellulose acetate based polymer electrolytes doped with "green" ionic mixture.

    PubMed

    Ramesh, S; Shanti, R; Morris, Ezra

    2013-01-02

    Polymer electrolytes were developed by solution casting technique utilizing the materials of cellulose acetate (CA), lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and deep eutectic solvent (DES). The DES is synthesized from the mixture of choline chloride and urea of 1:2 ratios. The increasing DES content well plasticizes the CA:LiTFSI:DES matrix and gradually improves the ionic conductivity and chemical integrity. The highest conducting sample was identified for the composition of CA:LiTFSI:DES (28 wt.%:12 wt.%:60 wt.%), which has the greatest ability to retain the room temperature ionic conductivity over the entire 30 days of storage time. The changes in FTIR cage peaks upon varying the DES content in CA:LiTFSI:DES prove the complexation. This complexation results in the collapse of CA matrix crystallinity, observed from the reduced intensity of XRD diffraction peaks. The DES-plasticized sample is found to be more heat-stable compared to pure CA. Nevertheless, the addition of DES diminishes the CA:LiTFSI matrix's heat-resistivity but at the minimum addition the thermal stability is enhanced.

  9. Bicyclic imidazolium ionic liquids as potential electrolytes for rechargeable lithium ion batteries

    SciTech Connect

    Liao, Chen; Shao, Nan; Bell, Jason R; Guo, Bingkun; Luo, Huimin; Jiang, Deen; Dai, Sheng

    2013-01-01

    A bicyclic imidazolium ionic liquids, 1-ethyl-2,3-trimethyleneimidazolium bis(tri fluoromethane sulfonyl)imide ([ETMIm][TFSI]), and reference imidazolium compounds, 1-ethyl-3-methylimidazolium bis(trifluoromethane sulfonyl)imide ([EMIm][TFSI]) and 1, 2-dimethyl-3-butylimidazolium bis(trifluoromethane sulfonyl)imide ([DMBIm][TFSI]), were synthesized and investigated as solvents for lithium ion batteries. Although the alkylation at the C-2 position of the imidazolium ring does not affect the thermal stability of the ionic liquids, with or without the presence of 0.5 molar lithium bis(trifluoromethane sulfonyl)imide (LiTFSI), the stereochemical structure of the molecules has shown profound influences on the electrochemical properties of the corresponding ionic liquids. [ETMIm][TFSI] shows better reduction stability than do [EMIm][TFSI] and [DMBIm][TFSI], as confirmed by both linear sweep voltammery (LSV) and theoretical calculation. The Li||Li cell impedance of 0.5M LiTFSI/[ETMIm][TFSI] is stabilized, whereas that of 0.5M LiTFSI/[DMBIm][TFSI] is still fluctuating after 20 hours, indicating a relatively stable solid electrolyte interphase (SEI) is formed in the former. Furthermore, the Li||graphite half-cell based on 0.5M LiTFSI/[BTMIm][TFSI] exhibits reversible capacity of 250mAh g-1 and 70mAh g-1 at 25 C, which increases to 330 mAh g-1 and 250 mAh g-1 at 50 C, under the current rate of C/20 and C/10, respectively. For comparison, the Li||graphite half-cell based on 0.5M LiTFSI/[DMBIm][TFSI] exhibits poor capacity retention under the same current rate at both temperatures.

  10. Ionic conductivity studies of solid oxide fuel cell electrolytes and theoretical modeling of an entire solid oxide fuel cell

    NASA Astrophysics Data System (ADS)

    Pornprasertsuk, Rojana

    orientations of single crystal YSZ and polycrystalline thin film YSZ deposited by pulsed laser deposition. The results indicate enhanced ionic conductivity and decreased activation energy of oxygen self-diffusion coefficients in the (100) Xe 3+ irradiated samples. However, a reduction in ionic conductivity was found in (100), (110), (111) Ar+ irradiated, and (111) Xe3+ irradiated single crystal YSZ, and Ar+ irradiated thin film YSZ. To gain insight into the diffusion mechanism of vacancies in YSZ, quantum simulations using Density Functional Theory (DFT) complemented with the KMC technique were employed. Quantum simulations were used to calculate the migration energy barriers at different dopant arrangements surrounding a diffusing oxygen vacancy in the bulk and dislocation core regions. KMC was then used to simulate a random walk process in a randomly distributed landscape of vacancies and Y atoms in a YSZ supercell containing different types of dislocations. Subsequently, the diffusion coefficients and the activation energies of the simulated diffusion process were extracted as a function of dislocation densities and doping concentrations. Furthermore, the similar simulation technique was modified to model impedance measurements in YSZ. The purpose of this study was to gain insight into the oxide ion diffusion process and the space charge double layer at the electrode-electrolyte interface subject to applied alternating potentials, as well as the dependence of impedance and double layer capacitance on the thickness of the electrolyte. KMC simulations were performed to simulate the movement of oxide ions using the migration barrier database obtained from previous DFT calculations with potential energy corrections under applied alternating potentials in different frequency domains. Combining the electrolyte studies with experimental studies of the cathode and anode reaction rates, a complete solid oxide fuel cell can be modeled using KMC. To study the effect of triple phase

  11. Toward Higher Energy Conversion Efficiency for Solid Polymer Electrolyte Dye-Sensitized Solar Cells: Ionic Conductivity and TiO2 Pore-Filling.

    PubMed

    Song, Donghoon; Cho, Woohyung; Lee, Jung Hyun; Kang, Yong Soo

    2014-04-03

    Even though the solid polymer electrolyte has many intrinsic advantages over the liquid electrolyte, its ionic conductivity and mesopore-filling are much poorer than those of the liquid electrolyte, limiting its practical application to electrochemical devices such as dye-sensitized solar cells (DSCs). Two major shortcomings associated with utilizing solid polymer electrolytes in DSCs are first discussed, low ionic conductivity and poor pore-filling in mesoporous photoanodes for DSCs. In addition, future directions for the successful utilization of solid polymer electrolytes toward improving the performance of DSCs are proposed. For instance, the facilitated mass-transport concept could be applied to increase the ionic conductivity. Modified biphasic and triple-phasic structures for the photoanode are suggested to take advantage of both the liquid- and solid-state properties of electrolytes.

  12. Oxygen reduction and evolution in an ionic liquid ([BMP][TFSA]) based electrolyte: A model study of the cathode reactions in Mg-air batteries

    NASA Astrophysics Data System (ADS)

    Law, Y. T.; Schnaidt, J.; Brimaud, S.; Behm, R. J.

    2016-11-01

    Aiming at a molecular scale understanding of the cathode processes in an Mg-air battery, we have investigated the oxygen reduction (ORR) and oxygen evolution (OER) reactions under well-defined conditions, using an ionic liquid (butyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl)amide, [BMP][TFSA]) based electrolyte and polycrystalline Au and glassy carbon, respectively, as model electrodes. Electrochemical measurements performed under enforced electrolyte flow provide information on the electrochemical and electrocatalytic properties of these electrodes, in particular on the reversibility of the ORR/OER both in the absence and in the presence of Mg2+ in the electrolyte, and on the build-up of a reaction inhibiting passivation layer (solid-electrolyte interphase). Further information on the nature of the deposits and their dependence both on the electrode material and on the potential cycling conditions is derived from scanning electron microscopy/energy dispersive X-ray spectroscopy and from X-ray photoelectron spectroscopy measurements performed ex situ after the electrochemical measurements. Consequences of these results on the understanding of the ORR/OER under these conditions and in particular of the nature and role of the solid-electrolyte interphase layer formed during potential cycling and their relevance for the operation of Mg-air batteries are discussed.

  13. Design and application of a novel ionic liquid with the property of strengthening coenzyme regeneration for whole-cell bioreduction in an ionic liquid-distilled water medium.

    PubMed

    Li, Jun; Wang, Pu; Huang, Jin; Sun, Jia

    2015-01-01

    Focusing on the task-specific properties of ionic liquids (ILs), a novel IL was designed by combining the quaternary ammonium cationic surfactant, [N1,1,1,1](+), with benign amino acid anion ([Cys](-)), and was successfully employed in whole-cell-catalyzed bioreduction by Trichodermaasperellum ZJPH0810 using an ionic liquid-distilled water medium. As expected, based on better understanding about the effects of ILs' characteristics of cations and anions on T. asperellum ZJPH0810-catalyzed bioreduction and the optimization of reaction parameters, the developed tetramethylammonium cysteine ([N1,1,1,1][Cys])-containing system is more efficient for the asymmetric reduction of 3,5-bis(trifluoromethyl) acetophenone to (R)-[3,5-bis(trifluoromethyl)phenyl] ethanol by whole-cell catalysis in contrast to that in monophasic aqueous system. Herein, a new biotechnological application for designed type of ILs is proposed due to its novel property of strengthening coenzyme regeneration during the bioreduction process. The designed IL [N1,1,1,1][Cys] was also evaluated in Candidatropicalis 104-catalyzed bioreduction to board its application, with remarkable success.

  14. All-solid-state flexible supercapacitors based on papers coated with carbon nanotubes and ionic-liquid-based gel electrolytes.

    PubMed

    Kang, Yu Jin; Chung, Haegeun; Han, Chi-Hwan; Kim, Woong

    2012-02-17

    All-solid-state flexible supercapacitors were fabricated using carbon nanotubes (CNTs), regular office papers, and ionic-liquid-based gel electrolytes. Flexible electrodes were made by coating CNTs on office papers by a drop-dry method. The gel electrolyte was prepared by mixing fumed silica nanopowders with ionic liquid, 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIM][NTf(2)]). This supercapacitor showed high power and energy performance as a solid-state flexible supercapacitor. The specific capacitance of the CNT electrodes was 135 F g(-1) at a current density of 2 A g(-1), when considering the mass of active materials only. The maximum power and energy density of the supercapacitors were 164 kW kg(-1) and 41 Wh kg(-1), respectively. Interestingly, the solid-state supercapacitor with the gel electrolyte showed comparable performance to the supercapacitors with ionic-liquid electrolyte. Moreover, the supercapacitor showed excellent stability and flexibility. The CNT/paper- and gel-based supercapacitors may hold great potential for low-cost and high-performance flexible energy storage applications.

  15. Electrolytic etching process provides effective bonding surface on stainless steel

    NASA Technical Reports Server (NTRS)

    1966-01-01

    Electrolytic etching process prepares surfaces of a stainless steel shell for reliable, high strength adhesive bonding to dielectric materials. The process uses a 25 percent aqueous solution of phosphoric acid.

  16. Forward osmosis process for dialysis fluid regeneration.

    PubMed

    Talaat, Khaled Mohamed

    2009-12-01

    In a preliminary experiment, 38% of the spent dialysis fluid water was reclaimed by a forward osmosis process through a cellulose triacetate membrane. The simplicity of forward osmosis and its minimal external energy requirements may allow the construction of a small bulk device that can reclaim a considerable portion of the water used in the patient's dialysis process. For developing an acceptable ambulatory dialysis system, decreasing the bulk of the fluid and equipment carried on the patient is essential. Forward osmosis may feasibly be used for dialysis fluid regeneration in ambulatory dialysis systems.

  17. Cycling performance and thermal stability of lithium polymer cells assembled with ionic liquid-containing gel polymer electrolytes

    NASA Astrophysics Data System (ADS)

    Yun, Ye Sun; Kim, Jin Hee; Lee, Sang-Young; Shim, Eun-Gi; Kim, Dong-Won

    Gel polymer electrolytes containing 1-butyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide and a small amount of additive (vinylene carbonate, fluoroethylene carbonate, and ethylene carbonate) are prepared, and their electrochemical properties are investigated. The cathodic limit of the gel polymer electrolytes can be extended to 0 V vs. Li by the formation of a protective solid electrolyte interphase on the electrode surface. Using these gel polymer electrolytes, lithium metal polymer cells composed of a lithium anode and a LiNi 1/3Co 1/3Mn 1/3O 2 cathode are assembled, and their cycling performances are evaluated at room temperature. The cells show good cycling performance, comparable to that of a cell assembled with gel polymer electrolyte containing standard liquid electrolyte (1.0 M LiPF 6 in ethylene carbonate/diethylene carbonate). Flammability tests and differential scanning calorimetry studies show that the presence of the ionic liquid in the gel polymer electrolyte considerably improves the safety and thermal stability of the cells.

  18. Thermostable gel polymer electrolyte based on succinonitrile and ionic liquid for high-performance solid-state supercapacitors

    NASA Astrophysics Data System (ADS)

    Pandey, Gaind P.; Liu, Tao; Hancock, Cody; Li, Yonghui; Sun, Xiuzhi Susan; Li, Jun

    2016-10-01

    A flexible, free-standing, thermostable gel polymer electrolyte based on plastic crystalline succinonitrile (SN) and ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate (BMImBF4) entrapped in copolymer poly(vinylidene fluoride-co-hexafluoropropylene) (PVdF-HFP) is prepared and optimized for application in solvent-free solid-state supercapacitors. The synthesized gel polymer electrolyte exhibits a high ionic conductivity over a wide temperature range (from ∼5 × 10-4 S cm-1 at -30 °C up to ∼1.5 × 10-2 S cm-1 at 80 °C) with good electrochemical stability window (-2.9 to 2.5 V). Thermal studies confirm that the SN containing gel polymer electrolyte remains stable in the same gel phase over a wide temperature range from -30 to 90 °C. The electric double layer capacitors (EDLCs) have been fabricated using activated carbon as active materials and new gel polymer electrolytes. Electrochemical performance of the EDLCs is assessed through cyclic voltammetry, galvanostatic charge-discharge cycling and impedance spectroscopy. The EDLC cells with the proper SN-containing gel polymer electrolyte has been found to give high specific capacitance 176 F g-1 at 0.18 A g-1 and 138 F g-1 at 8 A g-1. These solid-state EDLC cells show good cycling stability and the capability to retain ∼80% of the initial capacitance after 10,000 cycles.

  19. Ionic conductivity and battery characteristic studies of a new PAN-based Na+ ion conducting gel polymer electrolyte system

    NASA Astrophysics Data System (ADS)

    Krishna Jyothi, N.; Vijaya Kumar, K.; Sunita Sundari, G.; Narayana Murthy, P.

    2016-03-01

    Sodium ion conducting gel polymer electrolytes based on polyacrylonitrile (PAN) with ethylene carbonate and dimethyl formamide as plasticizing solvents are prepared by the solution cast technique. These electrolyte films are free standing, transparent and dimensionally stable. Na+ ions are derived from NaI. The structural properties of pure and complex formations have been examined by X-ray diffraction, Fourier transform infrared spectroscopic studies and differential scanning calorimetric studies. The variation of the conductivity with salt concentration ranging from 10 to 40 wt% is studied. The sample containing 30 wt% of NaI exhibits the highest conductivity of 2.35 × 10-4 S cm-1 at room temperature (303 K) and 1 × 10-3 S cm-1 at 373 K. The conductivity-temperature dependence of polymer electrolyte films obeys Arrhenius behavior with activation energy in the range of 0.25-0.46 eV. The transport numbers both electronic ( t e) and ionic ( t i) are evaluated using Wagner's polarization technique. It is revealed that the conducting species are predominantly due to ions. The ionic transport number of highest conducting film is found to be 0.991. Solid-state battery with configuration Na/(PAN + NaI)/(I2 + C + electrolyte) is developed using the highest conducting gel polymer electrolyte system and the discharge characteristics of the cell are evaluated over the load of 100 KΩ.

  20. Liquid crystal self-assembly of halloysite nanotubes in ionic liquids: a novel soft nanocomposite ionogel electrolyte with high anisotropic ionic conductivity and thermal stability

    NASA Astrophysics Data System (ADS)

    Zhao, Ningning; Liu, Yulin; Zhao, Xiaomeng; Song, Hongzan

    2016-01-01

    We report a novel class of liquid crystalline (LC) nanohybrid ionogels fabricated via self-assembly of natural halloysite nanotubes (HNTs) in ionic liquids (ILs). The obtained ionogels are very stable and nonvolatile and show LC phases over a wide temperature range. Remarkably, the nanocomposite ionogels exhibit high anisotropic ionic conductivity after shear, and their room temperature ionic conductivity can reach 3.8 × 10-3 S cm-1 for aligned nanotubes perpendicular to the electrode even when the HNTs content increases to 40 wt%, which is 380 times higher than that obtained for aligned nanotubes parallel to the electrode, which is 1.0 × 10-5 S cm-1. Crucially, the obtained LC nanocomposite ionogels have very high thermal stability, which can sustain 400 °C thermal treatment. The findings will promote the development of novel nanocomposite ionogel electrolytes with faster ion transport and larger anisotropic conductivity.We report a novel class of liquid crystalline (LC) nanohybrid ionogels fabricated via self-assembly of natural halloysite nanotubes (HNTs) in ionic liquids (ILs). The obtained ionogels are very stable and nonvolatile and show LC phases over a wide temperature range. Remarkably, the nanocomposite ionogels exhibit high anisotropic ionic conductivity after shear, and their room temperature ionic conductivity can reach 3.8 × 10-3 S cm-1 for aligned nanotubes perpendicular to the electrode even when the HNTs content increases to 40 wt%, which is 380 times higher than that obtained for aligned nanotubes parallel to the electrode, which is 1.0 × 10-5 S cm-1. Crucially, the obtained LC nanocomposite ionogels have very high thermal stability, which can sustain 400 °C thermal treatment. The findings will promote the development of novel nanocomposite ionogel electrolytes with faster ion transport and larger anisotropic conductivity. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr06888f

  1. Dissolution and regeneration of hide powder/cellulose composite in Gemini imidazolium ionic liquid.

    PubMed

    Wang, Guowei; Guo, Jiarong; Zhuang, Linghua; Wang, Yan; Xu, Bin

    2015-05-01

    Gemini imidazolium ionic liquid, 3,3'-[1,2-ethanediylbis (oxy-2,1-ethanediyl)]-bis[1-methyl-imidazolium]-dibromide ([C6O2(mim)2][Br]2), was used for the dissolution and regeneration of white hide powder (from pigskin), and blend white hide powder with cellulose for the easy production of white hide powder/cellulose composite. Dissolution performance of white hide powder in [C6O2(mim)2][Br]2 was studied. The native white hide powder and [C6O2(mim)2][Br]2 regenerated white hide powder were characterized by FT-IR, XRD, DSC-TG and FE-SEM. The results showed that [C6O2(mim)2][Br]2 was a good solvent to white hide powder. The dissolution time was 55 min when the white hide powder was 8% at 120°C. The dissolution time of [C6O2(mim)2][Br]2 for white hide powder was shorter than those of common ionic liquids. The triple helical structure of white hide powder was partly destroyed during [C6O2(mim)2][Br]2 dissolution. The possible mechanism of white hide powder dissolution in [C6O2(mim)2][Br]2 and the regeneration of white hide powder in methanol had been proposed. White hide powder/cellulose composites were successfully dissolved in [C6O2(mim)2][Br]2. The performance of white hide powder/cellulose film was measured by FT-IR and TG. The tensile strength, and elongation at break of white hide powder/cellulose composite films were tested. This work demonstrated that the white hide powder/cellulose composite exhibited some potential in collagen-based tissue engineering.

  2. Synthesis and Thermophysical Properties of Ether-Functionalized Sulfonium Ionic Liquids as Potential Electrolytes for Electrochemical Applications.

    PubMed

    Coadou, Erwan; Goodrich, Peter; Neale, Alex R; Timperman, Laure; Hardacre, Christopher; Jacquemin, Johan; Anouti, Mérièm

    2016-12-05

    During this work, a novel series of hydrophobic room temperature ionic liquids (ILs) based on five ether functionalized sulfonium cations bearing the bis{(trifluoromethyl)sulfonyl}imide, [NTf2 ](-) anion were synthesized and characterized. Their physicochemical properties, such as density, viscosity and ionic conductivity, electrochemical window, along with thermal properties including phase transition behavior and decomposition temperature, have been measured. All of these ILs showed large liquid range temperature, low viscosity, and good conductivity. Additionally, by combining DFT calculations along with electrochemical characterization it appears that these novel ILs show good electrochemical stability windows, suitable for the potential application as electrolyte materials in electrochemical energy storage devices.

  3. Synthesis and Thermophysical Properties of Ether‐Functionalized Sulfonium Ionic Liquids as Potential Electrolytes for Electrochemical Applications

    PubMed Central

    Goodrich, Peter; Neale, Alex R.; Timperman, Laure; Hardacre, Christopher; Anouti, Mérièm

    2016-01-01

    Abstract During this work, a novel series of hydrophobic room temperature ionic liquids (ILs) based on five ether functionalized sulfonium cations bearing the bis{(trifluoromethyl)sulfonyl}imide, [NTf2]− anion were synthesized and characterized. Their physicochemical properties, such as density, viscosity and ionic conductivity, electrochemical window, along with thermal properties including phase transition behavior and decomposition temperature, have been measured. All of these ILs showed large liquid range temperature, low viscosity, and good conductivity. Additionally, by combining DFT calculations along with electrochemical characterization it appears that these novel ILs show good electrochemical stability windows, suitable for the potential application as electrolyte materials in electrochemical energy storage devices. PMID:27717151

  4. Ionic liquids as an electrolyte for the electro synthesis of organic compounds.

    PubMed

    Kathiresan, Murugavel; Velayutham, David

    2015-12-25

    The use of ionic liquids (ILs) as a solvent and an electrolyte for electro organic synthesis has been reviewed. To date several ILs exist, however the ILs based on tetraalkylammonium, pyrrolidinium, piperidinium and imidazolium cations with BF4(-), PF6(-), and TFSI anions have been widely used and explored the most. Electro organic synthesis in ionic liquid media leading to the synthesis of a wide range of organic compounds has been discussed. Anodic oxidation or cathodic reduction will generate radical cation or anion intermediates, respectively. These radicals can undergo self coupling or coupling with other molecules yielding organic compounds of interest. The cation of the IL is known to stabilize the radical anion extensively. This stabilization effect has a specific impact on the electrochemical CO2 reduction and coupling to various organics. The relative stability of the intermediates in IL leads to the formation of specific products in higher yields. Electrochemical reduction of imidazolium or thiazolium based ILs generates N-heterocyclic carbenes that have been shown to catalyze a wide range of base or nucleophile catalyzed organic reactions in IL media, an aspect that falls into the category of organocatalysis. Electrochemical fluorination or selective electrochemical fluorination is another fascinating area that delivers selectively fluorinated organic products in Et3N·nHF or Et4NF·nHF adducts (IL) via anodic oxidation. Oxidative polymerization in ILs has been explored the most; although morphological changes were observed compared to the conventional methods, polymers were obtained in good yields and in some cases ILs were used as dopants to improve the desired properties.

  5. Cellulose acetate-lithium bis(trifluoromethanesulfonyl)imide solid polymer electrolyte: ATR-FTIR and ionic conductivity behavior

    NASA Astrophysics Data System (ADS)

    Mohd Razalli, Siti Masyitah; Sheikh Mohd Saaid, Siti Irma Yuana; Marwan Ali, Ab Malik; Hassan, Oskar Hasdinor; Yahya, Muhd Zu Azhan

    2015-05-01

    Solid polymer electrolytes (SPEs) based on cellulose acetate (CA) doped with lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) salt are prepared by solution cast technique. Attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy of the polymer salt complexes are recorded in the frequency range between 400 cm-1 and 4000 cm-1. The shifting of carbonyl band (C=O) at 1737 cm-1 to a lower wavenumber confirms the occurrence of complexation between the polymer and the salt. The electrochemical impedance spectroscopy (EIS) analysis discovered that the film with 25 wt.% of salt shows the highest ionic conductivity at room temperature. The change in real dielectric permittivity (ɛr) as a function of frequency at different salt concentrations which exhibits a dispersive behavior at low frequencies and decays at higher frequencies, shows the electrode polarization and space charge effect. The real modulus formalism (Mr) analysis shows that the polymer electrolytes in this work are ionic conductors.

  6. Electrochemical properties of an aluminum anode in an ionic liquid electrolyte for rechargeable aluminum-ion batteries.

    PubMed

    Choi, Sangwon; Go, Hyungho; Lee, Gibaek; Tak, Yongsug

    2017-02-01

    An aluminum metal, both native and with a very thin oxide film, was investigated as an anode for aluminum-ion batteries. Investigations were carried out in an acidic ionic liquid electrolyte, composed of AlCl3 in 1-ethyl-3-methylimidazolium chloride ([EMIm]Cl), with β-MnO2/C as a cathode. The battery based on Al metal with a very thin oxide film showed high capacity and stable surface corrosion.

  7. High-temperature solid-state dye-sensitized solar cells based on organic ionic plastic crystal electrolytes.

    PubMed

    Li, Qing; Zhao, Jie; Sun, Baoquan; Lin, Bencai; Qiu, Lihua; Zhang, Yueguang; Chen, Xiaojian; Lu, Jianmei; Yan, Feng

    2012-02-14

    Organic ionic plastic crystal, 1-ethyl-1-methyl pyrrolidinium iodide (P(12) I), is employed as the solid-state electrolytes for dye-sensitized solar cells. The fabricated solid-state devices show an overall power conversion efficiency of ~5.8% under AM 1.5 radiation (50 mW/cm(2) ) and excellent long-term stability at 80 °C.

  8. Surface coating from phosphonate ionic liquid electrolyte for the enhancement of the tribological performance of magnesium alloy.

    PubMed

    Jiménez, Ana Eva; Rossi, Antonella; Fantauzzi, Marzia; Espinosa, Tulia; Arias-Pardilla, Joaquin; Martínez-Nicolás, Ginés; Bermúdez, María-Dolores

    2015-05-20

    A chronoamperometric method has been applied for the growth of a surface coating on AZ31B magnesium alloy, using the imidazolium alkylphosphonate room-temperature ionic liquid 1-ethyl-3-methylimidazolium ethylphosphonate ([EMIM][EtPO3H]) as electrolyte. A surface coating layer is obtained after 4 h under a constant voltage bias of -0.8 V with respect to the standard electrode. The coating nucleation and growth process correlates well with a 3D progressive mechanism. X-ray photoelectron spectrometry (XPS) analysis of [EMIM][EtPO3H] shows new P 2p and O 1s peaks after its use as electrolyte, as a consequence of reaction between the phosphonate anion and the magnesium substrate. Angle-resolved XPS (ARXPS) analysis of [EMIM][EtPO3H] did not show any change in the composition of the surface before and after chronoamperometry, since the sampling depth (1.5 nm at the highest emission angle) is larger than the cation and anion sizes (ca. 7 and 5 Å, respectively). Characterization of the coating was made by scanning electron microscopy (SEM), focussed ion beam SEM, energy dispersive X-ray spectroscopy, XPS, and ARXPS. FIB-SEM shows that the coating presents a mean thickness of 374 (±36) nm and contains magnesium and aluminum phosphates. Linear reciprocating tribological tests under variable load show that the presence of the coating can reduce friction coefficients of the coated AZ31B against steel up to 32% and wear rates up to 90%, with respect to the uncoated alloy.

  9. Ionic liquid and plastic crystalline phases of pyrazolium imide salts as electrolytes for rechargeable lithium-ion batteries

    NASA Astrophysics Data System (ADS)

    Abu-Lebdeh, Yaser; Abouimrane, Ali; Alarco, Pierre-Jean; Armand, Michel

    A new member of the plastic crystal, pyrazolium imide family, N, N‧-diethyl-3-methylpyrazolium bis-(trifluoromethanesulfonyl)imide (DEMPyr123) was prepared. It showed a single, plastic crystalline phase that extends from 4.2 °C to its melting at 11.3 °C. When 10 mol% LiTFSI salt was added, the mixture showed ionic conductivities reaching 1.7 × 10 -3 S cm -1 at 20 °C, in the liquid state and 6.9 × 10 -4 S cm -1 at 5 °C, in the solid, plastic phase. A wide electrochemical stability window's of 5.5 V was observed by cyclic voltammetry of the molten salt mixture. Batteries were assembled with LiFePO 4/Li 4Ti 5O 12 electrodes and the salt mixture as an electrolyte. They showed a charge/discharge efficiency of 93% and 87% in the liquid and the plastic phase, respectively. The capacity retention was very good in both states with 90% of the initial capacity still available after 40 cycles. In general, the batteries showed good rate capability and cycle life performance in the ionic liquid phase that were sustained when the electrolyte transformed to the plastic phase. Comparison of the battery results with those of a classic (non-plastic crystal) ionic liquid has proven the advantage of the dual state of matter character in this electrolyte.

  10. Targeting adequate thermal stability and fire safety in selecting ionic liquid-based electrolytes for energy storage.

    PubMed

    Chancelier, L; Diallo, A O; Santini, C C; Marlair, G; Gutel, T; Mailley, S; Len, C

    2014-02-07

    The energy storage market relating to lithium based systems regularly grows in size and expands in terms of a portfolio of energy and power demanding applications. Thus safety focused research must more than ever accompany related technological breakthroughs regarding performance of cells, resulting in intensive research on the chemistry and materials science to design more reliable batteries. Formulating electrolyte solutions with nonvolatile and hardly flammable ionic liquids instead of actual carbonate mixtures could be safer. However, few definitions of thermal stability of electrolytes based on ionic liquids have been reported in the case of abuse conditions (fire, shortcut, overcharge or overdischarge). This work investigates thermal stability up to combustion of 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([C1C4Im][NTf2]) and 1-butyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide ([PYR14][NTf2]) ionic liquids, and their corresponding electrolytes containing lithium bis(trifluoromethanesulfonyl)imide LiNTf2. Their possible routes of degradation during thermal abuse testings were investigated by thermodynamic studies under several experimental conditions. Their behaviours under fire were also tested, including the analysis of emitted compounds.

  11. An Electrochemical NO₂ Sensor Based on Ionic Liquid: Influence of the Morphology of the Polymer Electrolyte on Sensor Sensitivity.

    PubMed

    Kuberský, Petr; Altšmíd, Jakub; Hamáček, Aleš; Nešpůrek, Stanislav; Zmeškal, Oldřich

    2015-11-11

    A systematic study was carried out to investigate the effect of ionic liquid in solid polymer electrolyte (SPE) and its layer morphology on the characteristics of an electrochemical amperometric nitrogen dioxide sensor. Five different ionic liquids were immobilized into a solid polymer electrolyte and key sensor parameters (sensitivity, response/recovery times, hysteresis and limit of detection) were characterized. The study revealed that the sensor based on 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIM][N(Tf)2]) showed the best sensitivity, fast response/recovery times, and low sensor response hysteresis. The working electrode, deposited from water-based carbon nanotube ink, was prepared by aerosol-jet printing technology. It was observed that the thermal treatment and crystallinity of poly(vinylidene fluoride) (PVDF) in the solid polymer electrolyte influenced the sensitivity. Picture analysis of the morphology of the SPE layer based on [EMIM][N(Tf)2] ionic liquid treated under different conditions suggests that the sensor sensitivity strongly depends on the fractal dimension of PVDF spherical objects in SPE. Their deformation, e.g., due to crowding, leads to a decrease in sensor sensitivity.

  12. Enhanced ionic conductivity of apatite-type lanthanum silicate electrolyte for IT-SOFCs through copper doping

    NASA Astrophysics Data System (ADS)

    Ding, Xifeng; Hua, Guixiang; Ding, Dong; Zhu, Wenliang; Wang, Hongjin

    2016-02-01

    Apatite-type Lanthanum silicate (LSO) is among the most promising electrolyte for intermediate temperature solid oxide fuel cells (IT-SOFCs) owing to the high conductivity and low activation energy at lower temperature than traditional doped-zirconia electrolyte. The ionic conductivity as well as the sintering density of lanthanum silicate oxy-apatite, La10Si6-xCuxO27-δ (LSCO, 0 ≤ x ≤ 2), was effectively enhanced through a small amount of doped copper. The phase composition, relative density, ionic conductivity and thermal expansion behavior of La10Si6-xCuxO27-δ was systematically investigated by X-ray diffraction (XRD), Archimedes' drainage method, scanning electron microscope (SEM), electrochemical impedance spectra (EIS) and thermal dilatometer techniques. With increasing copper doping content, the ionic conductivity of La10Si6-xCuxO27-δincreased, reaching a maximum of 4.8 × 10-2 S cm-1 at 800 °C for x = 1.5. The improved ionic conductivity could be primarily associated with the enhanced grain conductivity. The power output performance of NiO-LSCO/LSCO/LSCF single cell was superior to that obtained on NiO-LSO/LSO/LSCF at different temperatures using hydrogen as fuel and oxygen as oxidant, which could be attributed to the enhanced oxygen ionic conductivity as well as the sintering density for the copped doped lanthanum silicate. In conclusion, the apatite La10Si4.5Cu1.5O25.5 is a promising candidate electrolyte for IT-SOFCs.

  13. Ionic Liquid-Enhanced Solid State Electrolyte Interface (SEI) for Lithium Sulfur Batteries

    SciTech Connect

    Zheng, Jianming; Gu, Meng; Chen, Honghao; Meduri, Praveen; Engelhard, Mark H.; Zhang, Jiguang; Liu, Jun; Xiao, Jie

    2013-05-16

    Li-S battery is a complicated system with many challenges existing before its final market penetration. While most of the reported work for Li-S batteries is focused on the cathode design, we demonstrate in this work that the anode consumption accelerated by corrosive polysulfide solution also critically determines the Li-S cell performance. To validate this hypothesis, ionic liquid (IL) N-methyl-N-butylpyrrolidinium bis(trifluoromethylsulfonyl)imide (Py14TFSI) has been employed to modify the properties of SEI layer formed on Li metal surface in Li-S batteries. It is found that the IL-enhanced passivation film on the lithium anode surface exhibits much different morphology and chemical compositions, effectively protecting lithium metal from continuous attack by soluble polysulfides. Therefore, both cell impedance and the irreversible consumption of polysulfides on lithium metal are reduced. As a result, the Coulombic efficiency and the cycling stability of Li-S batteries have been greatly improved. After 120 cycles, Li-S battery cycled in the electrolyte containing IL demonstrates a high capacity retention of 94.3% at 0.1 C rate. These results unveil another important failure mechanism for Li-S batteries and shin the light on the new approaches to improve Li-S battery performances.

  14. Lithium-sulfur batteries based on nitrogen-doped carbon and ionic liquid electrolyte

    SciTech Connect

    Sun, Xiao-Guang; Wang, Xiqing; Mayes, Richard T; Dai, Sheng

    2012-01-01

    Nitrogen-doped mesoporous carbon (NC) and sulfur were used to prepare an NC/S composite cathode, which was evaluated in an ionic liquid electrolyte of 0.5 M lithium bis(trifluoromethane sulfonyl)imide (LiTFSI) in methylpropylpyrrolidinium bis(trifluoromethane sulfonyl)imide (MPPY.TFSI) by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and cycle testing. To facilitate the comparison, a C/S composite based on activated carbon (AC) without nitrogen doping was also fabricated under the same conditions as those for the NC/S composite. Compared with the AC/S composite, the NC/S composite showed enhanced activity toward sulfur reduction, as evidenced by the early onset sulfur reduction potential, higher redox current density in the CV test, and faster charge transfer kinetics as indicated by EIS measurement. At room temperature under a current density of 84 mA g-1 (C/20), the battery based on the NC/S composite exhibited higher discharge potential and an initial capacity of 1420 mAh g-1 whereas that based on the AC/S composite showed lower discharge potential and an initial capacity of 1120 mAh g-1. Both batteries showed similar capacity fading with cycling due to the intrinsic polysulfide solubility and the polysulfide shuttle mechanism; the capacity fading can be improved by further modification of the cathode.

  15. Ionically conducting PVA-LiClO4 gel electrolyte for high performance flexible solid state supercapacitors.

    PubMed

    Chodankar, Nilesh R; Dubal, Deepak P; Lokhande, Abhishek C; Lokhande, Chandrakant D

    2015-12-15

    The synthesis of polymer gel electrolyte having high ionic conductivity, excellent compatibility with active electrode material, mechanical tractability and long life is crucial to obtain majestic electrochemical performance for flexible solid state supercapacitors (FSS-SCs). Our present work describes effect of different polymers gel electrolytes on electrochemical properties of MnO2 based FSS-SCs device. It is revealed that, MnO2-FSS-SCs with polyvinyl alcohol (PVA)-Lithium perchlorate (LiClO4) gel electrolyte demonstrate excellent electrochemical features such as maximum operating potential window (1.2V), specific capacitance of 112Fg(-1) and energy density of 15Whkg(-1) with extended cycling stability up to 2500CV cycles. Moreover, the calendar life suggests negligible decrease in the electrochemical performance of MnO2-FSS-SCs after 20days.

  16. Enhanced Mixed Feedstock Processing Using Ionic Liquids

    SciTech Connect

    Simmons, Blake A

    2016-10-22

    Biomass pretreatment using certain ionic liquids (ILs) is very efficient, generally producing a substrate that is amenable to saccharification with fermentable sugar yields approaching theoretical limits. Although promising, several challenges must be addressed before IL pretreatment technology becomes commercially viable. Once of the most significant challenges is the affordable and scalable recovery and recycle or the IL itself. Pervaporation is a highly selective and scalable membrane separation process for quantitatively recovering volatile solutes or solvents directly from non-volatile solvents that could prove more versatile for IL dehydration than traditional solvent extraction processes, as well as efficient and energetically more advantageous than standard evaporative techniques. In this study we evaluated a commercially available pervaporation system for IL dehydration and recycling as part of an integrated IL pretreatment process using 1-ethyl-3-methylimidazolium acetate ([C2C1Im][OAc]) that has been proven to be very effective as a biomass pretreatment solvent. We demonstrate that >99.9 wt% [C2C1Im][OAc] can be recovered from aqueous solution and recycled at least five times. A preliminary techno-economic analysis validated the promising role of pervaporation in improving overall biorefinery process economics, especially in the case where other IL recovery technologies might lead to significant losses. These findings establish the foundation for further development of pervaporation as an effective method of recovering and recycling ILs using a commercially viable process technology.

  17. Electrowinning process with electrode compartment to avoid contamination of electrolyte

    SciTech Connect

    Poa, D.S.; Pierce, R.D.; Mulcahey, T.P.; Johnson, G.K.

    1991-12-31

    An electrolytic process and apparatus for reducing calcium oxide in a molten electrolyte of CaCl{sub 2}-CaF{sub 2} with a graphite anode in which particles or other contamination from the anode is restricted by the use of a porous barrier in the form of a basket surrounding the anode which may be removed from the electrolyte to burn the graphite particles, and wherein the calcium oxide feed is introduced to the anode compartment to increase the oxygen ion concentration at the anode.

  18. Electrowinning process with electrode compartment to avoid contamination of electrolyte

    DOEpatents

    Poa, Davis S.; Pierce, R. Dean; Mulcahey, Thomas P.; Johnson, Gerald K.

    1993-01-01

    An electrolytic process and apparatus for reducing calcium oxide in a molten electrolyte of CaCl.sub.2 -CaF.sub.2 with a graphite anode in which particles or other contamination from the anode is restricted by the use of a porous barrier in the form of a basket surrounding the anode which may be removed from the electrolyte to burn the graphite particles, and wherein the calcium oxide feed is introduced to the anode compartment to increase the oxygen ion concentration at the anode.

  19. Cryoelectrolysis—electrolytic processes in a frozen physiological saline medium

    PubMed Central

    Lugnani, Franco; Macchioro, Matteo

    2017-01-01

    Background Cryoelectrolysis is a new minimally invasive tissue ablation surgical technique that combines the ablation techniques of electrolytic ablation with cryosurgery. The goal of this study is to examine the hypothesis that electrolysis can take place in a frozen aqueous saline solution. Method To examine the hypothesis we performed a cryoelectrolytic ablation protocol in which electrolysis and cryosurgery are delivered simultaneously in a tissue simulant made of physiological saline gel with a pH dye. We measured current flow, voltage and extents of freezing and pH dye staining. Results Using optical measurements and measurements of currents, we have shown that electrolysis can occur in frozen physiological saline, at high subzero freezing temperatures, above the eutectic temperature of the frozen salt solution. It was observed that electrolysis occurs when the tissue resides at high subzero temperatures during the freezing stage and essentially throughout the entire thawing stage. We also found that during thawing, the frozen lesion temperature raises rapidly to high subfreezing values and remains at those values throughout the thawing stage. Substantial electrolysis occurs during the thawing stage. Another interesting finding is that electro-osmotic flows affect the process of cryoelectrolysis at the anode and cathode, in different ways. Discussion The results showing that electrical current flow and electrolysis occur in frozen saline solutions imply a mechanism involving ionic movement in the fluid concentrated saline solution channels between ice crystals, at high subfreezing temperatures. Temperatures higher than the eutectic are required for the brine to be fluid. The particular pattern of temperature and electrical currents during the thawing stage of frozen tissue, can be explained by the large amounts of energy that must be removed at the outer edge of the frozen lesion because of the solid/liquid phase transformation on that interface. Conclusion

  20. Carbon dioxide capture process with regenerable sorbents

    DOEpatents

    Pennline, Henry W.; Hoffman, James S.

    2002-05-14

    A process to remove carbon dioxide from a gas stream using a cross-flow, or a moving-bed reactor. In the reactor the gas contacts an active material that is an alkali-metal compound, such as an alkali-metal carbonate, alkali-metal oxide, or alkali-metal hydroxide; or in the alternative, an alkaline-earth metal compound, such as an alkaline-earth metal carbonate, alkaline-earth metal oxide, or alkaline-earth metal hydroxide. The active material can be used by itself or supported on a substrate of carbon, alumina, silica, titania or aluminosilicate. When the active material is an alkali-metal compound, the carbon-dioxide reacts with the metal compound to generate bicarbonate. When the active material is an alkaline-earth metal, the carbon dioxide reacts with the metal compound to generate carbonate. Spent sorbent containing the bicarbonate or carbonate is moved to a second reactor where it is heated or treated with a reducing agent such as, natural gas, methane, carbon monoxide hydrogen, or a synthesis gas comprising of a combination of carbon monoxide and hydrogen. The heat or reducing agent releases carbon dioxide gas and regenerates the active material for use as the sorbent material in the first reactor. New sorbent may be added to the regenerated sorbent prior to subsequent passes in the carbon dioxide removal reactor.

  1. Electrolytic trapping of iodine from process gas streams

    DOEpatents

    Horner, Donald E.; Mailen, James C.; Posey, Franz A.

    1977-01-25

    A method for removing molecular, inorganic, and organic forms of iodine from process gas streams comprises the electrolytic oxidation of iodine in the presence of cobalt-III ions. The gas stream is passed through the anode compartment of a partitioned electrolytic cell having a nitric acid anolyte containing a catalytic amount of cobalt to cause the oxidation of effluent iodine species to aqueous soluble species.

  2. Ionic Colloidal Molding as a Biomimetic Scaffolding Strategy for Uniform Bone Tissue Regeneration.

    PubMed

    Zhang, Jian; Jia, Jinpeng; Kim, Jimin P; Shen, Hong; Yang, Fei; Zhang, Qiang; Xu, Meng; Bi, Wenzhi; Wang, Xing; Yang, Jian; Wu, Decheng

    2017-02-21

    Inspired by the highly ordered nanostructure of bone, nanodopant composite biomaterials are gaining special attention for their ability to guide bone tissue regeneration through structural and biological cues. However, bone malformation in orthopedic surgery is a lingering issue, partly due to the high surface energy of traditional nanoparticles contributing to aggregation and inhomogeneity. Recently, carboxyl-functionalized synthetic polymers have been shown to mimic the carboxyl-rich surface motifs of non-collagenous proteins in stabilizing hydroxyapatite and directing intrafibrillar mineralization in-vitro. Based on this biomimetic approach, it is herein demonstrated that carboxyl functionalization of poly(lactic-co-glycolic acid) can achieve great material homogeneity in nanocomposites. This ionic colloidal molding method stabilizes hydroxyapatite precursors to confer even nanodopant packing, improving therapeutic outcomes in bone repair by remarkably improving mechanical properties of nanocomposites and optimizing controlled drug release, resulting in better cell in-growth and osteogenic differentiation. Lastly, better controlled biomaterial degradation significantly improved osteointegration, translating to highly regular bone formation with minimal fibrous tissue and increased bone density in rabbit radial defect models. Ionic colloidal molding is a simple yet effective approach of achieving materials homogeneity and modulating crystal nucleation, serving as an excellent biomimetic scaffolding strategy to rebuild natural bone integrity.

  3. Novel choline-based ionic liquids as safe electrolytes for high-voltage lithium-ion batteries

    NASA Astrophysics Data System (ADS)

    Yong, Tianqiao; Zhang, Lingzhi; Wang, Jinglun; Mai, Yongjin; Yan, Xiaodan; Zhao, Xinyue

    2016-10-01

    Three choline-based ionic liquids functionalized with trimethylsilyl, allyl, and cynoethyl groups are synthesized in an inexpensive route as safe electrolytes for high-voltage lithium-ion batteries. The thermal stabilities, viscosities, conductivities, and electrochemical windows of these ILs are reported. Hybrid electrolytes were formulated by doping with 0.6 M LiPF6/0.4 M lithium oxalydifluoroborate (LiODFB) as salts and dimethyl carbonate (DMC) as co-solvent. By using 0.6 M LiPF6/0.4 M LiODFB trimethylsilylated choline-based IL (SN1IL-TFSI)/DMC as electrolyte, LiCoO2/graphite full cell showed excellent cycling performance with a capacity of 152 mAh g-1 and 99% capacity retention over 90 cycles at a cut-off voltage of 4.4 V. The propagation rate of SN1IL-TFSI)/DMC electrolyte is only one quarter of the commercial electrolyte (1 M LiPF6 EC/DEC/DMC, v/v/v = 1/1/1), suggesting a better safety feature.

  4. Hydroxypropyl Cellulose Based Non-Volatile Gel Polymer Electrolytes for Dye-Sensitized Solar Cell Applications using 1-methyl-3-propylimidazolium iodide ionic liquid

    PubMed Central

    Khanmirzaei, Mohammad Hassan; Ramesh, S.; Ramesh, K.

    2015-01-01

    Gel polymer electrolytes using imidazolium based ionic liquids have attracted much attention in dye-sensitized solar cell applications. Hydroxypropyl cellulose (HPC), sodium iodide (NaI), 1-methyl-3-propylimidazolium iodide (MPII) as ionic liquid (IL), ethylene carbonate (EC) and propylene carbonate (PC) are used for preparation of non-volatile gel polymer electrolyte (GPE) system (HPC:EC:PC:NaI:MPII) for dye-sensitized solar cell (DSSC) applications. The highest ionic conductivity of 7.37 × 10−3 S cm−1 is achieved after introducing 100% of MPII with respect to the weight of HPC. Temperature-dependent ionic conductivity of gel polymer electrolytes is studied in this work. XRD patterns of gel polymer electrolytes are studied to confirm complexation between HPC polymer, NaI and MPII. Thermal behavior of the GPEs is studied using simultaneous thermal analyzer (STA) and differential scanning calorimetry (DSC). DSSCs are fabricated using gel polymer electrolytes and J-V centeracteristics of fabricated dye sensitized solar cells were analyzed. The gel polymer electrolyte with 100 wt.% of MPII ionic liquid shows the best performance and energy conversion efficiency of 5.79%, with short-circuit current density, open-circuit voltage and fill factor of 13.73 mA cm−2, 610 mV and 69.1%, respectively. PMID:26659087

  5. Hydroxypropyl Cellulose Based Non-Volatile Gel Polymer Electrolytes for Dye-Sensitized Solar Cell Applications using 1-methyl-3-propylimidazolium iodide ionic liquid

    NASA Astrophysics Data System (ADS)

    Khanmirzaei, Mohammad Hassan; Ramesh, S.; Ramesh, K.

    2015-12-01

    Gel polymer electrolytes using imidazolium based ionic liquids have attracted much attention in dye-sensitized solar cell applications. Hydroxypropyl cellulose (HPC), sodium iodide (NaI), 1-methyl-3-propylimidazolium iodide (MPII) as ionic liquid (IL), ethylene carbonate (EC) and propylene carbonate (PC) are used for preparation of non-volatile gel polymer electrolyte (GPE) system (HPC:EC:PC:NaI:MPII) for dye-sensitized solar cell (DSSC) applications. The highest ionic conductivity of 7.37 × 10-3 S cm-1 is achieved after introducing 100% of MPII with respect to the weight of HPC. Temperature-dependent ionic conductivity of gel polymer electrolytes is studied in this work. XRD patterns of gel polymer electrolytes are studied to confirm complexation between HPC polymer, NaI and MPII. Thermal behavior of the GPEs is studied using simultaneous thermal analyzer (STA) and differential scanning calorimetry (DSC). DSSCs are fabricated using gel polymer electrolytes and J-V centeracteristics of fabricated dye sensitized solar cells were analyzed. The gel polymer electrolyte with 100 wt.% of MPII ionic liquid shows the best performance and energy conversion efficiency of 5.79%, with short-circuit current density, open-circuit voltage and fill factor of 13.73 mA cm-2, 610 mV and 69.1%, respectively.

  6. Process to remove rare earth from IFR electrolyte

    DOEpatents

    Ackerman, J.P.; Johnson, T.R.

    1992-01-01

    The invention is a process for the removal of rare earths from molten chloride electrolyte salts used in the reprocessing of integrated fast reactor fuel (IFR). The process can be used either continuously during normal operation of the electrorefiner or as a batch process. The process consists of first separating the actinide values from the salt before purification by removal of the rare earths. After replacement of the actinides removed in the first step, the now-purified salt electrolyte has the same uranium and plutonium concentration and ratio as when the salt was removed from the electrorefiner.

  7. Process to remove rare earth from IFR electrolyte

    DOEpatents

    Ackerman, J.P.; Johnson, T.R.

    1994-08-09

    The invention is a process for the removal of rare earths from molten chloride electrolyte salts used in the reprocessing of integrated fast reactor fuel (IFR). The process can be used either continuously during normal operation of the electrorefiner or as a batch process. The process consists of first separating the actinide values from the salt before purification by removal of the rare earths. After replacement of the actinides removed in the first step, the now-purified salt electrolyte has the same uranium and plutonium concentration and ratio as when the salt was removed from the electrorefiner. 1 fig.

  8. Structural and Ionic Transport Properties of Protonic Conducting Solid Biopolymer Electrolytes Based on Carboxymethyl Cellulose Doped with Ammonium Fluoride.

    PubMed

    Ramlli, M A; Isa, M I N

    2016-11-10

    Fourier transform infrared (FT-IR), X-ray diffraction (XRD), and transference number measurement (TNM) techniques were applied to investigate the complexation, structural, and ionic transport properties of and the dominant charge-carrier species in a solid biopolymer electrolyte (SBE) system based on carboxymethyl cellulose (CMC) doped with ammonium fluoride (NH4F), which was prepared via a solution casting technique. The SBEs were partially opaque in appearance, with no phase separation. The presence of interactions between the host polymer (CMC) and the ionic dopant (NH4F) was proven by FT-IR analysis at the C-O band. XRD spectra analyzed using Origin 8 software disclose that the degree of crystallinity (χc%) of the SBEs decreased with the addition of NH4F, indicating an increase in the amorphous nature of the SBEs. Analysis of the ionic transport properties reveals that the ionic conductivity of the SBEs is dependent on the ionic mobility (μ) and diffusion of ions (D). TNM analysis confirms that the SBEs are proton conductors.

  9. Ionic mechanisms of Ca(2+)-dependent electrolyte transport across equine sweat gland epithelium.

    PubMed

    Ko, W H; Chan, H C; Chew, S B; Wong, P Y

    1996-06-15

    1. The ionic mechanism involved in Ca(2+)-stimulated electrolyte transport in cultured equine sweat gland epithelial cells was studied using the short-circuit current (ISC) technique. 2. Microscopy revealed that the cultured cells grown on Millipore filters formed polarized monolayers with tight junctions. Monolayers exhibited a mean transepithelial resistance of 333.9 +/- 40.4 omega cm2. 3. Ca(2+)-mobilizing agents, A23187 (1 microM) or thapsigargin (0.01-1 microM), stimulated ISC while forskolin exerted little effect on the ISC. 4. Replacement of external Cl- by gluconate significantly reduced the ISC by 63% when stimulated by 0.1 microM thapsigargin. Residual ISC could be abolished (> 99%) by elimination of HCO3- from the bathing solution. 5. Basolateral addition of bumetanide (0.1 mM), ouabain (0.01 mM) and acetazolamide (45 microM) and apical addition of methyl isobutyl amiloride (MIA, 1-100 microM) all had inhibitory effects on the thapsigargin-stimulated ISC to various extents. 6. Substantial current inhibition could be obtained using 4, 4'-diisothiocyanatostilbene-2,2'-disulphonic acid (DIDS) and diphenylamine-2-carboxylate (DPC) in a concentration-dependent manner. 7. The K+ channel blocker barium (5 mM) was effective on both sides of the epithelium with a much larger effect on the basolateral side. 8. The inhibitory effects of acetazolamide, amiloride, MIA, DIDS and DPC on the thapsigargin-stimulated ISC were also observed when a Cl(-)-free solution was used. 9. The results provide evidence for Ca(2+)-stimulated HCO3- as well as Cl- secretion by equine sweat gland epithelium.

  10. Influence of the structure of the anion in an ionic liquid electrolyte on the electrochemical performance of a silicon negative electrode for a lithium-ion battery

    NASA Astrophysics Data System (ADS)

    Yamaguchi, Kazuki; Domi, Yasuhiro; Usui, Hiroyuki; Shimizu, Masahiro; Matsumoto, Kuninobu; Nokami, Toshiki; Itoh, Toshiyuki; Sakaguchi, Hiroki

    2017-01-01

    We investigated the influence of the anions in ionic liquid electrolytes on the electrochemical performance of a silicon (Si) negative electrode for a lithium-ion battery. While the electrode exhibited poor cycle stability in tetrafluoroborate-based and propylene carbonate-based electrolytes, better cycle performance was achieved in bis(fluorosulfonyl)amide (FSA-)- and bis(trifluoromethanesulfonyl)amide (TFSA-)-based electrolytes, in which the discharge capacity of a Si electrode was more than 1000 mA h g-1 at the 100th cycle. It is considered that a surface film derived from FSA-- and TFSA--based electrolytes effectively suppressed continuous decomposition of the electrolyte. In a capacity limitation test, a discharge capacity of 1000 mA h g-1 was maintained even after about the 1600th cycle in the FSA--based electrolyte, which corresponds to a cycle life almost twice as long as that in TFSA--based electrolyte. This result should be explained by the high structural stability of FSA--derived surface film. In addition, better rate capability with a discharge capacity of 700 mA h g-1 was obtained at a high current rate of 6 C (21 A g-1) in FSA--based electrolyte, which was 7-fold higher than that in TFSA--based electrolyte. These results clarified that FSA--based ionic liquid electrolyte is the most promising candidate for Si-based negative electrodes.

  11. Dielectric properties and fluctuating relaxation processes of poly(methyl methacrylate) based polymeric nanocomposite electrolytes

    NASA Astrophysics Data System (ADS)

    Sengwa, R. J.; Choudhary, Shobhna

    2014-06-01

    Solid polymer nanocomposite electrolytes (SPNEs) consisted of poly(methyl methacrylate) (PMMA) and lithium perchlorate (LiClO4) of molar ratio C=O:Li+=4:1 with varying concentration of montmorillonite (MMT) clay as nanofiller have been prepared by classical solution casting and high intensity ultrasonic assisted solution casting methods. The dielectric/electrical dispersion behaviour of these electrolytes was studied by dielectric relaxation spectroscopy at ambient temperature. The dielectric loss tangent and electric modulus spectra have been analyzed for relaxation processes corresponding to the side groups rotation and the segmental motion of PMMA chain, which confirm their fluctuating behaviour with the sample preparation methods and also with change of MMT concentration. The feasibility of these relaxation fluctuations has been explained using a transient complex structural model based on Lewis acid-base interactions. The low permittivity and moderate dc ionic conductivity at ambient temperature suggest the suitability of these electrolytes in fabrication of ion conducting electrochromic devices and lithium ion batteries. The amorphous behaviour and the exfoliated/intercalated MMT structures of these nanocomposite electrolytes were confirmed by X-ray diffraction measurements.

  12. Relationship between pore size and reversible and irreversible immobilization of ionic liquid electrolytes in porous carbon under applied electric potential

    DOE PAGES

    Mahurin, Shannon M.; Mamontov, Eugene; Thompson, Matthew W.; ...

    2016-10-04

    Transport of electrolytes in nanoporous carbon-based electrodes largely defines the function and performance of energy storage devices. Here, using molecular dynamics simulation and quasielastic neutron scattering, we investigate the microscopic dynamics of a prototypical ionic liquid electrolyte, [emim][Tf2N], under applied electric potential in carbon materials with 6.7 nm and 1.5 nm pores. The simulations demonstrate the formation of dense layers of counter-ions near the charged surfaces, which is reversible when the polarity is reversed. In the experiment, the ions immobilized near the surface manifest themselves in the elastic scattering signal. The experimentally observed ion immobilization near the wall is fullymore » reversible as a function of the applied electric potential in the 6.7 nm, but not in the 1.5 nm nanopores. In the latter case, remarkably, the first application of the electric potential leads to apparently irreversible immobilization of cations or anions, depending on the polarity, near the carbon pore walls. This unexpectedly demonstrates that in carbon electrode materials with the small pores, which are optimal for energy storage applications, the polarity of the electrical potential applied for the first time after the introduction of an ionic liquid electrolyte may define the decoration of the small pore walls with ions for prolonged periods of time and possibly for the lifetime of the electrode.« less

  13. Relationship between pore size and reversible and irreversible immobilization of ionic liquid electrolytes in porous carbon under applied electric potential

    SciTech Connect

    Mahurin, Shannon M.; Mamontov, Eugene; Thompson, Matthew W.; Zhang, Pengfei; Turner, C. Heath; Cummings, Peter T.; Dai, Sheng

    2016-10-04

    Transport of electrolytes in nanoporous carbon-based electrodes largely defines the function and performance of energy storage devices. Here, using molecular dynamics simulation and quasielastic neutron scattering, we investigate the microscopic dynamics of a prototypical ionic liquid electrolyte, [emim][Tf2N], under applied electric potential in carbon materials with 6.7 nm and 1.5 nm pores. The simulations demonstrate the formation of dense layers of counter-ions near the charged surfaces, which is reversible when the polarity is reversed. In the experiment, the ions immobilized near the surface manifest themselves in the elastic scattering signal. The experimentally observed ion immobilization near the wall is fully reversible as a function of the applied electric potential in the 6.7 nm, but not in the 1.5 nm nanopores. In the latter case, remarkably, the first application of the electric potential leads to apparently irreversible immobilization of cations or anions, depending on the polarity, near the carbon pore walls. This unexpectedly demonstrates that in carbon electrode materials with the small pores, which are optimal for energy storage applications, the polarity of the electrical potential applied for the first time after the introduction of an ionic liquid electrolyte may define the decoration of the small pore walls with ions for prolonged periods of time and possibly for the lifetime of the electrode.

  14. Relationship between pore size and reversible and irreversible immobilization of ionic liquid electrolytes in porous carbon under applied electric potential

    NASA Astrophysics Data System (ADS)

    Mahurin, Shannon M.; Mamontov, Eugene; Thompson, Matthew W.; Zhang, Pengfei; Turner, C. Heath; Cummings, Peter T.; Dai, Sheng

    2016-10-01

    Transport of electrolytes in nanoporous carbon-based electrodes largely defines the function and performance of energy storage devices. Using molecular dynamics simulation and quasielastic neutron scattering, we investigate the microscopic dynamics of a prototypical ionic liquid electrolyte, [emim][Tf2N], under applied electric potential in carbon materials with 6.7 nm and 1.5 nm pores. The simulations demonstrate the formation of dense layers of counter-ions near the charged surfaces, which is reversible when the polarity is reversed. In the experiment, the ions immobilized near the surface manifest themselves in the elastic scattering signal. The experimentally observed ion immobilization near the wall is fully reversible as a function of the applied electric potential in the 6.7 nm, but not in the 1.5 nm nanopores. In the latter case, remarkably, the first application of the electric potential leads to apparently irreversible immobilization of cations or anions, depending on the polarity, near the carbon pore walls. This unexpectedly demonstrates that in carbon electrode materials with the small pores, which are optimal for energy storage applications, the polarity of the electrical potential applied for the first time after the introduction of an ionic liquid electrolyte may define the decoration of the small pore walls with ions for prolonged periods of time and possibly for the lifetime of the electrode.

  15. All-solid state supercapacitors operating at 3.5 V by using ionic liquid based polymer electrolytes

    NASA Astrophysics Data System (ADS)

    Ayalneh Tiruye, Girum; Muñoz-Torrero, David; Palma, Jesus; Anderson, Marc; Marcilla, Rebeca

    2015-04-01

    All-solid state supercapacitors (SCs) using Ionic Liquid based Polymer Electrolyte (IL-b-PE) and activated carbon were assembled and characterized electrochemically. IL-b-PE consisted of a binary blend of a polymeric ionic liquid (PIL), poly(diallyldimethylammonium) bis(trifluoromethanesulfonyl)imide (pDADMATFSI), and their corresponding ionic liquid (IL), N-butyl-N-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide (PYR14TFSI) in a ratio of 40:60,w/w respectively. Assembling of supercapacitors simply consists of facing two impregnated electrodes without the need of additional separator. Several all-solid state SCs with impregnation ratios (IL-b-PE mass/active material mass) ranging from 5 to 18 were characterized. An all-solid state SC with impregnation ratio of 7 showed the best performance with specific capacitance (Cam) and real energy (Ereal) of 100 F g-1 and 32 Wh kg-1, respectively. After increasing temperatures to 60 °C, the performance of SCs further improved exhibiting Ereal values of 42 Wh kg-1 at 1 mA cm-2. These figures of merit are only slightly lower than those obtained for convectional SCs using pure PYR14TFS and much higher as compared with other solid SCs based on conventional polymer electrolytes. This is mainly due to the high electrochemical stability of this IL-b-PE that allows these solid SCs to operate at maximum voltages as high as 3.5 V for the first time.

  16. Rigid-flexible coupling high ionic conductivity polymer electrolyte for an enhanced performance of LiMn2O4/graphite battery at elevated temperature.

    PubMed

    Hu, Pu; Duan, Yulong; Hu, Deping; Qin, Bingsheng; Zhang, Jianjun; Wang, Qingfu; Liu, Zhihong; Cui, Guanglei; Chen, Liquan

    2015-03-04

    LiMn2O4-based batteries exhibit severe capacity fading during cycling or storage in LiPF6-based liquid electrolytes, especially at elevated temperatures. Herein, a novel rigid-flexible gel polymer electrolyte is introduced to enhance the cyclability of LiMn2O4/graphite battery at elevated temperature. The polymer electrolyte consists of a robust natural cellulose skeletal incorporated with soft segment poly(ethyl α-cyanoacrylate). The introduction of the cellulose effectively overcomes the drawback of poor mechanical integrity of the gel polymer electrolyte. Density functional theory (DFT) calculation demonstrates that the poly(ethyl α-cyanoacrylate) matrices effectively dissociate the lithium salt to facilitate ionic transport and thus has a higher ionic conductivity at room temperature. Ionic conductivity of the gel polymer electrolyte is 3.3 × 10(-3) S cm(-1) at room temperature. The gel polymer electrolyte remarkably improves the cycling performance of LiMn2O4-based batteries, especially at elevated temperatures. The capacity retention after the 100th cycle is 82% at 55 °C, which is much higher than that of liquid electrolyte (1 M LiPF6 in carbonate solvents). The polymer electrolyte can significantly suppress the dissolution of Mn(2+) from surface of LiMn2O4 because of strong interaction energy of Mn(2+) with PECA, which was investigated by DFT calculation.

  17. Acidic Ionic Liquids.

    PubMed

    Amarasekara, Ananda S

    2016-05-25

    Ionic liquid with acidic properties is an important branch in the wide ionic liquid field and the aim of this article is to cover all aspects of these acidic ionic liquids, especially focusing on the developments in the last four years. The structural diversity and synthesis of acidic ionic liquids are discussed in the introduction sections of this review. In addition, an unambiguous classification system for various types of acidic ionic liquids is presented in the introduction. The physical properties including acidity, thermo-physical properties, ionic conductivity, spectroscopy, and computational studies on acidic ionic liquids are covered in the next sections. The final section provides a comprehensive review on applications of acidic ionic liquids in a wide array of fields including catalysis, CO2 fixation, ionogel, electrolyte, fuel-cell, membrane, biomass processing, biodiesel synthesis, desulfurization of gasoline/diesel, metal processing, and metal electrodeposition.

  18. Electrolytes

    MedlinePlus

    ... part of blood that doesn't contain cells. Sodium, potassium, and chloride levels can also be measured as part of ... in urine. It test the levels of calcium, chloride, potassium, sodium, and other electrolytes. References Chernecky CC, Berger BJ. ...

  19. Holey graphene nanosheets with surface functional groups as high-performance supercapacitors in ionic-liquid electrolyte.

    PubMed

    Yang, Cheng-Hsien; Huang, Po-Ling; Luo, Xu-Feng; Wang, Chueh-Han; Li, Chi; Wu, Yi-Hsuan; Chang, Jeng-Kuei

    2015-05-22

    Pores and surface functional groups are created on graphene nanosheets (GNSs) to improve supercapacitor properties in a butylmethylpyrrolidinium-dicyanamide (BMP-DCA) ionic liquid (IL) electrolyte. The GNS electrode exhibits an optimal capacitance of 330 F g(-1) and a satisfactory rate capability within a wide potential range of 3.3 V at 25 °C. Pseudocapacitive effects are confirmed using X-ray photoelectron spectroscopy. Under the same conditions, carbon nanotube and activated carbon electrodes show capacitances of 80 and 81 F g(-1) , respectively. Increasing the operation temperature increases the conductivity and decreases the viscosity of the IL electrolyte, further improving cell performance. At 60 °C, a symmetric-electrode GNS supercapacitor with the IL electrolyte is able to deliver maximum energy and power densities of 140 Wh kg(-1) and 52.5 kW kg(-1) (based on the active material on both electrodes), respectively, which are much higher than the 20 Wh kg(-1) and 17.8 kW kg(-1) obtained for a control cell with a conventional organic electrolyte.

  20. Electrochemical and structural characterization of polymer gel electrolytes based on a PEO copolymer and an imidazolium-based ionic liquid for dye-sensitized solar cells.

    PubMed

    Freitas, Flavio S; de Freitas, Jilian N; Ito, Bruno I; De Paoli, Marco-A; Nogueira, Ana F

    2009-12-01

    Polymer electrolytes based on mixtures of poly(ethylene oxide-co-propylene oxide) and 1-methyl-3-propyl-imidazolium iodide (MPII) were investigated, aiming at their application in dye-sensitized solar cells (DSSC). The interactions between the copolymer and the ionic liquid were analyzed by infrared spectroscopy and (1)H NMR. The results show interactions between the ether oxygen in the polymer and the hydrogen in the imidazolium cations. The ionic conductivities, electrochemical behaviors, and thermal properties of the electrolytes containing different concentrations of MPII were investigated. The electrolyte containing 70 wt % MPII presented the highest ionic conductivity (2.4 x 10(-3) S cm(-1)) and a diffusion coefficient of 1.9 x 10(-7) cm(2) s(-1). The influence of LiI addition to the electrolytes containing different concentrations of MPII was also investigated. The DSSC assembled with the electrolyte containing 70 wt % MPII showed an efficiency of 3.84% at 100 mW cm(-2). The stability of the devices for a period of 30 days was also evaluated using sealed cells. The devices assembled with the electrolyte containing less ionic liquid showed to be more stable.

  1. Dynamics and relaxation of charge carriers in poly(methylmethacrylate)-based polymer electrolytes embedded with ionic liquid

    NASA Astrophysics Data System (ADS)

    Pal, P.; Ghosh, A.

    2015-12-01

    In the present paper, we have studied dynamics and relaxation of the charge carriers in polymethylmethacrylate-lithium bis(trifluoromethane sulfonyl)imide polymer electrolytes embedded with 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide ionic liquid. We have analyzed the frequency dependent conductivity spectra using the random free-energy barrier model coupled with the contribution of electrode polarization in the low frequency region. The temperature dependence of ionic conductivity, and relaxation time obtained from the analysis of the spectra exhibits Vogel-Tammann-Fulcher type behavior. The Barton-Nakajima-Namikawa relation is consistent with the results obtained from the random free-energy barrier model. The scaling of ac conductivity spectra has been performed to understand the effect of temperature as well as the composition on the relaxation mechanism. The analysis of the ac conductivity also clearly indicates the existence of a nearly constant loss phenomenon at low temperatures or at high frequencies.

  2. Ionic conductivity of mesoporous block copolymer membranes in liquid electrolyte as a function of copolymer and homopolymer molecular weight

    NASA Astrophysics Data System (ADS)

    Wong, David; Mullin, Scott; Stone, Greg; Battaglia, Vincent; Balsara, Nitash

    2011-03-01

    Mesoporous block copolymer membranes have been synthesized using poly(styrene-block-ethylene-block-polystyrene) (SES). A series of symmetric SES copolymers and PS homopolymers have been studied at different blending fractions. Ionic conductivities of the porous films in a liquid electrolyte, 1.0 M Li PF6 in ethylene carbonate/diethyl carbonate, compare favorably to conventional battery separators and generally increase with internal surface area, as measured by nitrogen adsorption. Characterization of the effects of pore structure and SES morphology on conductivity will be presented. Support from the U.S. Department of Energy Office of Vehicles Technologies (FCVT) under the Batteries for Advanced Transportation Technologies (BATT) Program.

  3. Application of bis(fluorosulfonyl)imide-based ionic liquid electrolyte to silicon-nickel-carbon composite anode for lithium-ion batteries

    NASA Astrophysics Data System (ADS)

    Sugimoto, Toshinori; Atsumi, Yosuke; Kono, Michiyuki; Kikuta, Manabu; Ishiko, Eriko; Yamagata, Masaki; Ishikawa, Masashi

    An ionic liquid electrolyte containing bis(fluorosulfonyl)imide (FSI) anion without any solvent is applied to a silicon-nickel-carbon (Si-Ni-carbon) composite anode for rechargeable lithium (Li)-ion batteries. The FSI-based ionic liquid electrolyte successfully provides a stable, reversible capacity for the Si-Ni-carbon anode, which is comparable to the performance observed in a typical commercialized solvent-based electrolyte, while a common ionic liquid electrolyte containing bis(trifluoromethanesulfonyl)imide (TFSI) anion without FSI presents no reversible capacity to the anode at all. Ac impedance analysis reveals that the FSI-based electrolyte provides very low interfacial and charge-transfer resistances at the Si-based composite anode, even when compared to the corresponding resistances observed in a typical solvent-based electrolyte. Galvanostatic cycling of the Si-based composite anode in the FSI-based electrolyte with a charge limitation of 800 mAh g -1 is stable and provides a discharge capacity of 790 mAh g -1 at the 50th cycle, corresponding to a cycle efficiency of 98.8%.

  4. Mechanisms of low temperature capture and regeneration of CO2 using diamino protic ionic liquids.

    PubMed

    Simons, Tristan J; Verheyen, Thomas; Izgorodina, Ekaterina I; Vijayaraghavan, R; Young, Scott; Pearson, Andrew K; Pas, Steven J; MacFarlane, Douglas R

    2016-01-14

    Carbon dioxide (CO2) chemical absorption and regeneration was investigated in two diamino carboxylate protic ionic liquids (PILs), dimethylethylenediamine formate (DMEDAH formate) and dimethylpropylenediamine acetate (DMPDAH acetate), using novel calorimetric techniques. The PILs under study have previously been shown to possess a CO2 absorption capacity similar to the industrial standard, 30% aqueous MEA, while requiring much lower temperatures to release the captured CO2. We show that this is in part due to the fact that the PILs exhibit enthalpies of CO2 desorption as low as 40 kJ mol(-1), significantly lower than the 85 kJ mol(-1) required for 30% aqueous MEA. Computational and spectroscopic analyses were used to probe the mechanism of CO2 capture, which was found to proceed via the formation of carbamate moieties on the primary amine of both DMEDAH and DMPDAH. Evidence was also found that weakly acidic counter-ions such as formate and acetate provide, unexpectedly, an additional proton acceptor site in the traditional carbamate mechanism, revealing opportunities to increase CO2 uptake capacity in the future through careful design of the anion and cation used in the PIL capture agent.

  5. Method for producing electricity from a fuel cell having solid-oxide ionic electrolyte

    DOEpatents

    Mason, David M.

    1984-01-01

    Stabilized quadrivalent cation oxide electrolytes are employed in fuel cells at elevated temperatures with a carbon and/or hydrogen containing fuel anode and an oxygen cathode. The fuel cell is operated at elevated temperatures with conductive metallic coatings as electrodes and desirably having the electrolyte surface blackened. Of particular interest as the quadrivalent oxide is zirconia.

  6. Effect of epoxidation level on thermal properties and ionic conductivity of epoxidized natural rubber solid polymer nanocomposite electrolytes

    NASA Astrophysics Data System (ADS)

    Harun, Fatin; Chan, Chin Han; Sim, Lai Har; Winie, Tan; Zainal, Nurul Fatahah Asyqin

    2015-08-01

    Effect of epoxide content on the thermal and conductivity properties of epoxidized natural rubber (ENR) solid polymer nanocomposite electrolytes was investigated. Commercial available epoxidized natural rubber having 25 (ENR25) and 50 mole% (ENR50) epoxide, respectively were incorporated with lithium perchlorate (LiClO4) salt and titanium dioxide (TiO2) nanofiller via solution casting method. The solid polymer nanocomposite electrolytes were characterized by differential scanning calorimetry (DSC) and impedance spectroscopy (IS) for their thermal properties and conductivity, respectively. It was evident that introduction of LiClO4 causes a greater increase in glass transition temperature (Tg) and ionic conductivity of ENR50 as compared to ENR25. Upon addition of TiO2 in ENR/LiClO4 system, a remarkable Tg elevation was observed for both ENRs where ENR50 reveals a more pronounced changes. It is interesting to note that they exhibit different phenomenon in ionic conductivity with TiO2 loading where ENR25 shows enhancement of conductivity while ENR50 shows declination.

  7. Solvent-free, PYR 1ATFSI ionic liquid-based ternary polymer electrolyte systems . I. Electrochemical characterization

    NASA Astrophysics Data System (ADS)

    Kim, Guk-Tae; Appetecchi, Giovanni B.; Alessandrini, Fabrizio; Passerini, Stefano

    The electrical properties of solvent-free, PEO-LiTFSI solid polymer electrolytes (SPEs), incorporating different N-alkyl- N-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide, PYR 1ATFSI, ionic liquids (ILs), are reported. For this purpose, PYR 1ATFSI materials containing side alkyl groups with different chain-length and branching, i.e., n-propyl, sec-propyl, n-butyl, iso-butyl, sec-butyl and n-pentyl, were properly synthesized and homogeneously incorporated into the SPE samples without phase separation. The addition of ILs to PEO-LiTFSI electrolytes results in a large increase of the conductivity and in a decrease of the interfacial resistance with the lithium metal anode. Most of the PEO-LiTFSI-PYR 1ATFSI samples showed similar ionic conductivities (>10 -4 S cm -1 at 20 °C) and stable interfacial resistance values (400 Ω cm 2 at 40 °C and 3000 Ω cm 2 at 20 °C) upon several months of storage. Preliminary battery tests have shown that Li/P(EO) 10LiTFSI + 0.96 PYR 1ATFSI/LiFePO 4 solid-state cells are capable to deliver a capacity of 125 mAh g -1 and 100 mAh g -1 at 30 °C and 25 °C, respectively.

  8. Effect of epoxidation level on thermal properties and ionic conductivity of epoxidized natural rubber solid polymer nanocomposite electrolytes

    SciTech Connect

    Harun, Fatin; Chan, Chin Han; Winie, Tan; Sim, Lai Har; Zainal, Nurul Fatahah Asyqin

    2015-08-28

    Effect of epoxide content on the thermal and conductivity properties of epoxidized natural rubber (ENR) solid polymer nanocomposite electrolytes was investigated. Commercial available epoxidized natural rubber having 25 (ENR25) and 50 mole% (ENR50) epoxide, respectively were incorporated with lithium perchlorate (LiClO{sub 4}) salt and titanium dioxide (TiO{sub 2}) nanofiller via solution casting method. The solid polymer nanocomposite electrolytes were characterized by differential scanning calorimetry (DSC) and impedance spectroscopy (IS) for their thermal properties and conductivity, respectively. It was evident that introduction of LiClO{sub 4} causes a greater increase in glass transition temperature (T{sub g}) and ionic conductivity of ENR50 as compared to ENR25. Upon addition of TiO{sub 2} in ENR/LiClO{sub 4} system, a remarkable T{sub g} elevation was observed for both ENRs where ENR50 reveals a more pronounced changes. It is interesting to note that they exhibit different phenomenon in ionic conductivity with TiO{sub 2} loading where ENR25 shows enhancement of conductivity while ENR50 shows declination.

  9. The correlation of the properties of pyrrolidinium-based ionic liquid electrolytes with the discharge-charge performances of rechargeable Li-O2 batteries

    NASA Astrophysics Data System (ADS)

    Li, Yu; Zhang, Zhonglin; Duan, Donghong; Sun, Yanbo; Wei, Guoqiang; Hao, Xiaogang; Liu, Shibin; Han, Yunxia; Meng, Weijuan

    2016-10-01

    Pyrrolidinium-based ionic liquids (ILs), such as PYR13TFSI, PYR14TFSI, and PYR1(2O1)TFSI, exhibit high thermal and electrochemical stability with wide electrochemical windows as electrolytes for application to rechargeable Li-O2 batteries. In this work, several fundamental properties of three ILs are measured: the ionic conductivity, oxygen solubility, and oxygen diffusion coefficient. The oxygen electro-reduction kinetics is characterized using cyclic voltammetry. The performances of Li-O2 batteries with these IL electrolytes are also investigated using electrochemical impedance spectroscopy and galvanostatic discharge-charge tests. The results demonstrate that the PYR1(2O1)TFSI electrolyte battery has a higher first-discharge voltage than the PYR13TFSI electrolyte and PYR14TFSI electrolyte batteries. Both PYR13TFSI- and PYR1(2O1)TFSI-based batteries exhibit higher first-discharge capacities and better cycling stabilities than the PYR14TFSI-based battery for 30 cycles. A theoretical analysis of the experimental results shows that the diffusion coefficient and solubility of oxygen in the electrolyte remarkably affect the discharge capacity and cycling stability of the batteries. Particularly, the oxygen diffusion coefficient of the IL electrolyte can effectively facilitate the electrochemical oxygen electro-reduction reaction and oxygen concentration distribution in the catalyst layers of air electrodes. The oxygen diffusion coefficient and oxygen solubility improvements of IL electrolytes can enhance the discharge-charge performances of Li-O2 batteries.

  10. Ionic conductivity of dual-phase polymer electrolytes comprised of NBR/SBR latex films swollen with lithium salt solutions

    SciTech Connect

    Matsumoto, Morihiko; Ichino, Toshihiro; Rutt, J.S.; Nishi, Shiro . NTT Interdisciplinary Research Lab.)

    1994-08-01

    Dual-phase polymer electrolytes (DPE) with high ionic conductivity and good mechanical strength were prepared by swelling poly(acrylonitrile-co-butadiene) rubber (NBR) and poly(styrene-co-butadiene) rubber (SBR) mixed latex films with lithium salt solutions (e.g., 1M LiClO[sub 4]/[gamma]-butyrolactone). The latex films retain particle morphology in the solid state. The NBR phase (formed from fused NBR latex particles) is polar and is impregnated selectively with polar lithium salt solutions, yielding ion-conductive channels, whereas the SBR phase (formed from fused SBR latex particles) is nonpolar and is not impregnated, providing a mechanically supportive matrix. The ionic conductivity of the DPE increased dramatically with increasing content of lithium salt solution, and higher amounts of solution were imbibed with increasing content of NBR relative to SBR. Several factors which affect the ionic conductivity of this system were examined, and the highest ionic conductivity (>10[sup [minus]3] S/cm) was obtained when either an NBR/SBR 70/30 (w/w) or a 50/50 (w/w) latex film was saturated with 1M LiClO[sub 4]/[gamma]-BL solution or 1M LiClO[sub 4]/[gamma]-BL/DME solution. Ion-conductive behavior changed critically with increasing lithium salt solution uptake. At low levels of lithium salt solution uptake, evidence suggested that ionic conductivity of the absorbed lithium salt solution was strongly influenced by the presence of the NBR in the ion-conductive channel, but at higher levels, the effects of the NBR were reduced and free'' lithium salt solution was present.

  11. Investigation of Ionic Conductivity of Nanocomposite Polymer Electrolytes Based On PVDF-HFP/PVC Blend, LiClO4 and TiO2 Nanofiller

    NASA Astrophysics Data System (ADS)

    Basri, N. H.; Mohamed, N. S.

    2010-07-01

    The effects of nanosized TiO2 on the conductivity of PVDF-HFP/PVC-LiClO4 was studied by means of impedance spectroscopy and x-ray diffraction (XRD). The addition of TiO2 nanofiller increases the crystalline phase fraction but slightly increases the conductivity of the PVDF-HFP/PVC-LiClO4 complex. The increase in conductivity is attributed to the formation of highly conducting layer at the electrolyte/filler interface. The temperature dependence of conductivity obeys the VTF type behaviour while the transference number confirms that the electrolyte containing 6 wt.% TiO2 is an ionic conductor are ionic conductors.

  12. Studies on structural, thermal and AC conductivity scaling of PEO-LiPF6 polymer electrolyte with added ionic liquid [BMIMPF6

    NASA Astrophysics Data System (ADS)

    Chaurasia, S. K.; Saroj, A. L.; Shalu, Singh, V. K.; Tripathi, A. K.; Gupta, A. K.; Verma, Y. L.; Singh, R. K.

    2015-07-01

    Preparation and characterization of polymer electrolyte films of PEO+10wt.% LiPF6 + xwt.% BMIMPF6 (1-butyl-3-methylimidazolium hexafluorophosphate) containing dopant salt lithium hexafluorophosphate (LiPF6) and ionic liquid (BMIMPF6) having common anion PF6 - are reported. The ionic conductivity of the polymer electrolyte films has been found to increase with increasing concentration of BMIMPF6 in PEO+10 wt.% LiPF6 due to the plasticization effect of ionic liquid. DSC and XRD results show that the crystallinity of polymer electrolyte decreases with BMIMPF6 concentration which, in turn, is responsible for the increase in ionic conductivity. FTIR spectroscopic study shows the complexation of salt and/or ionic liquid cations with the polymer backbone. Ion dynamics behavior of PEO+LiPF6 as well as PEO+LiPF6 + BMIMPF6 polymer electrolytes was studied by frequency dependent conductivity, σ(f) measurements. The values σ(f) at various temperatures have been analyzed in terms of Jonscher power law (JPL) and scaled with respect to frequency which shows universal power law characteristics at all temperatures.

  13. Acid sorption regeneration process using carbon dioxide

    DOEpatents

    King, C. Judson; Husson, Scott M.

    2001-01-01

    Carboxylic acids are sorbed from aqueous feedstocks onto a solid adsorbent in the presence of carbon dioxide under pressure. The acids are freed from the sorbent phase by a suitable regeneration method, one of which is treating them with an organic alkylamine solution thus forming an alkylamine-carboxylic acid complex which thermally decomposes to the desired carboxylic acid and the alkylamine.

  14. Ionic liquid-based electrolyte with binary lithium salts for high performance lithium-sulfur batteries

    NASA Astrophysics Data System (ADS)

    Wu, Feng; Zhu, Qizhen; Chen, Renjie; Chen, Nan; Chen, Yan; Ye, Yusheng; Qian, Ji; Li, Li

    2015-11-01

    Rechargeable Li-S batteries have suffered several technical obstacles, such as rapid capacity fading and low coulombic efficiency. To overcome these problems, we design new electrolytes containing N-methoxyethyl-N-methylpyrrolidinium bis(trifluoromethanesulfonyl)-imide (Pyr1,2O1TFSI) and tri(ethylene glycol)dimethyl ether (TEGDME) in mass ratio of 7:3. Moreover, Lithium difluoro(oxalate)borate (LiODFB) is introduced for the modification. Although the addition of LiODFB as additive lead to extremely high viscosity of electrolyte and inferior performance of the cells, the electrolyte containing lithium bis(trifluoromethanesulfonyl)imide (LiTFSI, 0.84 nm) and LiODFB (0.60 nm) mixture with a total molar concentration of 0.4 mol kg-1 as binary lithium salt shows excellent electrochemical performance. The Pyr1,2O1TFSI/TEGDME electrolyte with LiTFSI/LiODFB binary lithium salts in mole ratio of 6:4 is obtained after optimizing ratio. The Li-S cells containing this electrolyte system show excellent capacity and cycle performance, whose initial discharge capacity is 1264.4 mAh g-1, and retains 911.4 mAh g-1 after 50 cycles with the coulombic efficiency more than 95%. It can be attributed the solid-electrolyte interphase (SEI)-forming ability of LiODFB which protect Li anode from suffering lithium dendrites and prevent the shuttle phenomenon. The novel electrolytes provide good cycling stability and high coulombic efficiency for the Li-S batteries, which is suggested as a promising electrolyte for Li-S batteries.

  15. Destruction of organic wastes by ammonium peroxydisulfate with electrolytic regeneration of the oxidant

    SciTech Connect

    Cooper, J.F.; Wang, J.F.; Krueger, R.; King, K.

    1997-07-01

    Research is reported concerning a new aqueous process for oxidative destruction of solid- and liquid organic wastes. This process uses acidified ammonium peroxydisulfate and operates at ambient pressure and at 80- to 100 {degrees}C. The oxidant may be efficiently regenerated by electrolysis of the sulfate by-product at Pt anodes, even in the presence of organic and inorganic contaminants expected to be entrained in the cycle. Integral rate constants were determined for the oxidation of 25 diverse organic compounds at low (50 ppm) concentrations through fixed-time experiments with excess oxidant and a Pt wire catalyst. For high initial concentrations, uncatalyzed mineralization rates were measured for waste surrogates including kerosene, triethylamine, ion exchange resin, oxalic acid, trinitrotoluene, and cellulose. A packed bed reactor was tested with ethylene glycol, with offgas analysis by mass spectroscopy. Rate data extrapolate to throughputs of approximately 200 kg/m{sub 3}-day. The process may benefit the destruction of highly toxic or specialized industrial wastes as well as the organic fraction of mixed wastes.

  16. An atomistic picture of the regeneration process in dye sensitized solar cells

    PubMed Central

    Schiffmann, Florian; VandeVondele, Joost; Hutter, Jürg; Urakawa, Atsushi; Wirz, Ronny; Baiker, Alfons

    2010-01-01

    A highly efficient mechanism for the regeneration of the cis-bis(isothiocyanato)bis(2,2′-bipyridyl-4,4′-dicarboxylato)-ruthenium(II) sensitizing dye (N3) by I- in acetonitrile has been identified by using molecular dynamics simulation based on density functional theory. Barrier–free complex formation of the oxidized dye with both I- and , and facile dissociation of and from the reduced dye are key steps in this process. In situ vibrational spectroscopy confirms the reversible binding of I2 to the thiocyanate group. Additionally, simulations of the electrolyte near the interface suggest that acetonitrile is able to cover the (101) surface of anatase with a passivating layer that inhibits direct contact of the redox mediator with the oxide, and that the solvent structure specifically enhances the concentration of I- at a distance which further favors rapid dye regeneration. PMID:20207948

  17. Ionic screening of charged impurities in electrolytically gated graphene: A partially linearized Poisson-Boltzmann model.

    PubMed

    Sharma, P; Mišković, Z L

    2015-10-07

    We present a model describing the electrostatic interactions across a structure that consists of a single layer of graphene with large area, lying above an oxide substrate of finite thickness, with its surface exposed to a thick layer of liquid electrolyte containing salt ions. Our goal is to analyze the co-operative screening of the potential fluctuation in a doped graphene due to randomness in the positions of fixed charged impurities in the oxide by the charge carriers in graphene and by the mobile ions in the diffuse layer of the electrolyte. In order to account for a possibly large potential drop in the diffuse later that may arise in an electrolytically gated graphene, we use a partially linearized Poisson-Boltzmann (PB) model of the electrolyte, in which we solve a fully nonlinear PB equation for the surface average of the potential in one dimension, whereas the lateral fluctuations of the potential in graphene are tackled by linearizing the PB equation about the average potential. In this way, we are able to describe the regime of equilibrium doping of graphene to large densities for arbitrary values of the ion concentration without restrictions to the potential drop in the electrolyte. We evaluate the electrostatic Green's function for the partially linearized PB model, which is used to express the screening contributions of the graphene layer and the nearby electrolyte by means of an effective dielectric function. We find that, while the screened potential of a single charged impurity at large in-graphene distances exhibits a strong dependence on the ion concentration in the electrolyte and on the doping density in graphene, in the case of a spatially correlated two-dimensional ensemble of impurities, this dependence is largely suppressed in the autocovariance of the fluctuating potential.

  18. Influence of microstructure and AlPO4 secondary-phase on the ionic conductivity of Li1.3Al0.3Ti1.7(PO4)3 solid-state electrolyte

    NASA Astrophysics Data System (ADS)

    Yu, Shicheng; Mertens, Andreas; Gao, Xin; Gunduz, Deniz Cihan; Schierholz, Roland; Benning, Svenja; Hausen, Florian; Mertens, Josef; Kungl, Hans; Tempel, Hermann; Eichel, Rüdiger-A.

    2016-09-01

    A ceramic solid-state electrolyte of lithium aluminum titanium phosphate with the composition of Li1.3Al0.3Ti1.7(PO4)3 (LATP) was synthesized by a sol-gel method using a pre-dissolved Ti-source. The annealed LATP powders were subsequently processed in a binder-free dry forming method and sintered under air for the pellet preparation. Phase purity, density, microstructure as well as ionic conductivity of the specimen were characterized. The highest density (2.77gṡcm-3) with an ionic conductivity of 1.88×10-4 Sṡcm-1 (at 30∘C) was reached at a sintering temperature of 1100∘C. Conductivity of LATP ceramic electrolyte is believed to be significantly affected by both, the AlPO4 secondary phase content and the ceramic electrolyte microstructure. It has been found that with increasing sintering temperature, the secondary-phase content of AlPO4 increased. For sintering temperatures above 1000∘C, the secondary phase has only a minor impact, and the ionic conductivity is predominantly determined by the microstructure of the pellet, i.e. the correlation between density, porosity and particle size. In that respect, it has been demonstrated, that the conductivity increases with increasing particle size in this temperature range and density.

  19. Impact of Environmental Conditions (pH, Ionic Strength, And Electrolyte Type) On The Surface Charge And Aggregation Of Silver Nanoparticles Suspensions

    EPA Science Inventory

    The impact of capping agents and environmental conditions (pH, ionic strength, and background electrolytes) on surface charge and aggregation potential of silver nanoparticles (AgNPs) suspensions were investigated. Capping agents are chemicals used in the synthesis of nanopartic...

  20. New electrolyte systems for capillary zone electrophoresis of metal cations and non-ionic organic compounds

    SciTech Connect

    Shi, Youchun

    1995-06-19

    Excellent separations of metal ions can be obtained very quickly by capillary electrophoresis provided a weak complexing reagent is incorporated into the electrolyte to alter the effective mobilities of the sample ions. Indirect photometric detection is possible by also adding a UV-sensitive ion to the electrolyte. Separations are described using phthalate, tartrate, lactate or hydroxyisobutyrate as the complexing reagent. A separation of twenty-seven metal ions was achieved in only 6 min using a lactate system. A mechanism for the separation of lanthanides is proposed for the hydroxyisobutyrate system.

  1. Coulombic effects and multicomponent ionic dispersion during transport of electrolytes in porous media

    NASA Astrophysics Data System (ADS)

    Muniruzzaman, Muhammad; Haberer, Christina; Grathwohl, Peter; Rolle, Massimo

    2014-05-01

    We study the influence of Coulombic effects on transport of charged species in saturated porous media in advection-dominated flow regimes. We focus on transverse hydrodynamic dispersion and we performed quasi two-dimensional flow-through experiments in homogeneous and spatially variable flow fields to investigate transport of dilute electrolyte solutions. The experiments were conducted at flow velocities (1.0, 1.5 and 6 m/day) where advection is the dominant mass transfer process. High-resolution measurements at the outlet were performed to determine the concentration of different cations and anions. In order to interpret the laboratory experiments we develop a two-dimensional numerical model. The adopted modeling approach is based on a multicomponent formulation, charge conservation, and the accurate description of local transverse dispersion. The latter entails a non-linear dependence of the transverse dispersion coefficient on the flow velocity as well as a compound-specific dependence on the molecular diffusion of the transported solutes. The model was benchmarked by comparing the results of the 2D steady-state multicomponent simulations with 1D transient results of PHREEQC in homogeneous scenarios, and it was successively used to quantitatively evaluate the experimental results in both homogeneous and heterogeneous porous media. Our experimental and modeling results show that Coulombic cross-coupling of dispersive fluxes of charged species in porous media significantly affects the lateral displacement of charged ions in both homogeneous and heterogeneous flow-through systems. Such effects are remarkable not only in diffusion-dominated but also in advection-dominated flow regimes.

  2. Process for electrolytic deposition of metals on zirconium materials

    DOEpatents

    Donaghy, Robert E.

    1979-01-30

    A process for the electrolytic deposition of a metal layer on an article comprised of zirconium or a zirconium alloy is disclosed. The article is activated in an aged aqueous solution comprising from about 10 to about 20 grams per liter ammonium bifluoride and from about 0.75 to about 2 grams per liter of sulfuric acid. The solution is aged by immersion of pickled zirconium in the solution for at least about 10 minutes. The loosely adhering film formed on the article in the activating step is removed and the article is contacted with an electrolytic plating solution containing the metal to be deposited on the article in the presence of an electrode receiving current.

  3. Porous polymer electrolytes with high ionic conductivity and good mechanical property for rechargeable batteries

    NASA Astrophysics Data System (ADS)

    Liang, Bo; Jiang, Qingbai; Tang, Siqi; Li, Shengliang; Chen, Xu

    2016-03-01

    Porous polymer electrolytes (PPEs) are attractive for developing lithium-ion batteries because of the combined advantages of liquid and solid polymer electrolytes. In the present study, a new porous polymer membrane doped with phytic acid (PA) is prepared, which is used as a crosslinker in polymer electrolyte matrix and can also plasticize porous polymer electrolyte membranes, changing them into soft tough flexible materials. A PEO-PMMA-LiClO4-x wt.% PA (x = weight of PA/weight of polymer, PEO: poly(ethylene oxide); PMMA: poly(methyl methacrylate)) polymer membrane is prepared by a simple evaporation method. The effects of the ratio of PA to PEO-PMMA on the properties of the porous membrane, including morphology, porous structure, and mechanical property, are systematically studied. PA improves the porous structure and mechanical properties of polymer membrane. The maximum tensile strength and elongation of the porous polymer membranes are 20.71 MPa and 45.7% at 15 wt.% PA, respectively. Moreover, the PPEs with 15 wt.% PA has a conductivity of 1.59 × 10-5 S/cm at 20 °C, a good electrochemical window (>5 V), and a low interfacial resistance. The results demonstrate the compatibility of the mechanical properties and conductivity of the PPEs, indicating that PPEs have good application prospects for lithium-ion batteries.

  4. Capacitance of Ti3C2Tx MXene in Ionic Liquid Electrolyte

    SciTech Connect

    Lin, Zifeng; Barbara, Daffos; Taberna, Pierre-Louis; Van Aken, Katherine; Anasori, Babak; Gogotsi, Yury G.; Simon, Patrice

    2016-04-14

    Ti3C2Tx MXene, a two-dimensional (2D) early transition metal carbide, has shown an extremely high volumetric capacitance in aqueous electrolytes, but in a narrow voltage window (less than 1.23 V). The utilization of MXene materials in ionic liquid electrolytes with a large voltage window has never been addressed. Here, we report the preparation of the Ti3C2Tx MXene ionogel film by vacuum filtration for use as supercapacitor electrodes operating in 1-Ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMI-TFSI) neat ionic liquid electrolyte. Due to the disordered structure of the Ti3C2Tx hydrogel film and a stable spacing after vacuum drying, achieved through ionic liquid electrolyte immersion of the Ti3C2Tx hydrogel film, the Ti3C2Tx surface became accessible to EMI+ and TFSI- ions. A capacitance of 70 F g-1 together with a large voltage window of 3 V was obtained at a scan rate of 20 mV s-1 in neat EMI-TFSI electrolyte. The electrochemical signature indicates a capacitive behavior even at a high scan rate (500 mV s-1) and a high power performance. This work opens up the possibilities of using MXene materials with various ionic liquid electrolytes.

  5. Separators for Li-Ion and Li-Metal Battery Including Ionic Liquid Based Electrolytes Based on the TFSI− and FSI− Anions

    PubMed Central

    Kirchhöfer, Marija; von Zamory, Jan; Paillard, Elie; Passerini, Stefano

    2014-01-01

    The characterization of separators for Li-ion or Li-metal batteries incorporating hydrophobic ionic liquid electrolytes is reported herein. Ionic liquids made of N-butyl-N-methylpyrrolidinium (PYR14+) or N-methoxyethyl-N-methylpyrrolidinium (PYR12O1+), paired with bis(trifluoromethanesulfonyl)imide (TFSI−) or bis(fluorosulfonyl)imide (FSI−) anions, were tested in combination with separators having different chemistries and morphologies in terms of wetting behavior, Gurley and McMullin number, as well as Li/(Separator + Electrolyte) interfacial properties. It is shown that non-functionalized microporous polyolefin separators are poorly wetted by FSI−-based electrolytes (contrary to TFSI−-based electrolytes), while the ceramic coated separator Separion® allows good wetting with all electrolytes. Furthermore, by comparing the lithium solid electrolyte interphase (SEI) resistance evolution at open circuit and during cycling, depending on separator morphologies and chemistries, it is possible to propose a scale for SEI forming properties in the order: PYR12O1FSI > PYR14FSI > PYR14TFSI > PYR12O1TFSI. Finally, the impact the separator morphology is evidenced by the SEI resistance evolution and by comparing Li electrodes cycled using separators with two different morphologies. PMID:25153637

  6. Tandem dissolution of UO3 in amide-based acidic ionic liquid and in situ electrodeposition of UO2 with regeneration of the ionic liquid: a closed cycle

    SciTech Connect

    Wanigasekara, Eranda; Freiderich, John W.; Sun, Xiao-Guang; Meisner, Roberta A.; Luo, Huimin; Delmau, Lætitia H.; Dai, Sheng; Moyer, Bruce A.

    2016-05-19

    A closed cycle is demonstrated for the tandem dissolution and electroreduction of UO3 to UO2 with regeneration of the acidic ionic liquid. The dissolution is achieved by use of the acidic ionic liquid N,N-dimethylacetimidium bis(trifluoromethanesulfonimide) in 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonimide) serving as the diluent. Bulk electrolysis performed at 1.0 V vs. Ag reference yields a dark brown-black uranium deposit (UO2) on the cathode. Anodic oxidation of water in the presence of dimethylacetamide regenerates the acidic ionic liquid. We have demonstrated the individual steps in the cycle together with a sequential dissolution, electroreduction, and regeneration cycle.

  7. An ether-functionalised cyclic sulfonium based ionic liquid as an electrolyte for electrochemical double layer capacitors

    NASA Astrophysics Data System (ADS)

    Neale, Alex R.; Murphy, Sinead; Goodrich, Peter; Schütter, Christoph; Hardacre, Christopher; Passerini, Stefano; Balducci, Andrea; Jacquemin, Johan

    2016-09-01

    A novel cyclic sulfonium cation-based ionic liquid (IL) with an ether-group appendage and the bis{(trifluoromethyl)sulfonyl}imide anion was synthesised and developed for electrochemical double layer capacitor (EDLC) testing. The synthesis and chemical-physical characterisation of the ether-group containing IL is reported in parallel with a similarly sized alkyl-functionalised sulfonium IL. Results of the chemical-physical measurements demonstrate how important transport properties, i.e. viscosity and conductivity, can be promoted through the introduction of the ether-functionality without impeding thermal, chemical or electrochemical stability of the IL. Although the apparent transport properties are improved relative to the alkyl-functionalised analogue, the ether-functionalised sulfonium cation-based IL exhibits moderately high viscosity, and poorer conductivity, when compared to traditional EDLC electrolytes based on organic solvents (propylene carbonate and acetonitrile). Electrochemical testing of the ether-functionalised sulfonium IL was conducted using activated carbon composite electrodes to inspect the performance of the IL as a solvent-free electrolyte for EDLC application. Good cycling stability was achieved over the studied range and the performance was comparable to other solvent-free, IL-based EDLC systems. Nevertheless, limitations of the attainable performance are primarily the result of sluggish transport properties and a restricted operative voltage of the IL, thus highlighting key aspects of this field which require further attention.

  8. Engineering the electrochemical capacitive properties of graphene sheets in ionic-liquid electrolytes by correct selection of anions.

    PubMed

    Shi, Minjie; Kou, Shengzhong; Yan, Xingbin

    2014-11-01

    Graphene sheet (GS)-ionic liquid (IL) supercapacitors are receiving intense interest because their specific energy density far exceeds that of GS-aqueous electrolytes supercapacitors. The electrochemical properties of ILs mainly depend on their diverse ions, especially anions. Therefore, identifying suitable IL electrolytes for GSs is currently one of the most important tasks. The electrochemical behavior of GSs in a series of ILs composed of 1-ethyl-3-methylimidazolium cation (EMIM(+)) with different anions is systematically studied. Combined with the formula derivation and building models, it is shown that the viscosity, ion size, and molecular weight of ILs affect the electrical conductivity of ILs, and thus, determine the electrochemical performances of GSs. Because the EMIM-dicyanamide IL has the lowest viscosity, ion size, and molecular weight, GSs in it exhibit the highest specific capacitance, smallest resistance, and best rate capability. In addition, because the tetrafluoroborate anion (BF4(-)) has the best electrochemical stability, the GS-[EMIM][BF4] supercapacitor has the widest potential window, and thus, displays the largest energy density. These results may provide valuable information for selecting appropriate ILs and designing high-performance GS-IL supercapacitors to meet different needs.

  9. Single-Ion Block Copoly(ionic liquid)s as Electrolytes for All-Solid State Lithium Batteries.

    PubMed

    Porcarelli, Luca; Shaplov, Alexander S; Salsamendi, Maitane; Nair, Jijeesh R; Vygodskii, Yakov S; Mecerreyes, David; Gerbaldi, Claudio

    2016-04-27

    Polymer electrolytes have been proposed as replacement for conventional liquid electrolytes in lithium-ion batteries (LIBs) due to their intrinsic enhanced safety. Nevertheless, the power delivery of these materials is limited by the concentration gradient of the lithium salt. Single-ion conducting polyelectrolytes represent the ideal solution since their nature prevents polarization phenomena. Herein, the preparation of a new family of single-ion conducting block copolymer polyelectrolytes via reversible addition-fragmentation chain transfer polymerization technique is reported. These copolymers comprise poly(lithium 1-[3-(methacryloyloxy)propylsulfonyl]-1-(trifluoromethylsulfonyl)imide) and poly(ethylene glycol) methyl ether methacrylate blocks. The obtained polyelectrolytes show low Tg values in the range of -61 to 0.6 °C, comparatively high ionic conductivity (up to 2.3 × 10(-6) and 1.2 × 10(-5) S cm(-1) at 25 and 55 °C, respectively), wide electrochemical stability (up to 4.5 V versus Li(+)/Li), and a lithium-ion transference number close to unity (0.83). Owing to the combination of all mentioned properties, the prepared polymer materials were used as solid polyelectrolytes and as binders in the elaboration of lithium-metal battery prototypes with high charge/discharge efficiency and excellent specific capacity (up to 130 mAh g(-1)) at C/15 rate.

  10. Synthesis and Compatibility of Ionic Liquid Containing Rod-Coil Polyimide Gel Electrolytes with Lithium Metal Electrodes

    NASA Technical Reports Server (NTRS)

    Tigelaar, Dean M.; Palker, Allyson E.; Meador, Mary Ann B.; Bennett, William R.

    2008-01-01

    A highly cross-linked polyimide-polyethylene oxide copolymer has been synthesized that is capable of holding large volumes of liquid component, simultaneously maintaining good dimensional stability. An amine end capped oligomer was made that was imidized in solution, followed by reaction with a triisocyanate in the presence of desired additives at ambient temperature. Polymer films are able to hold over 4 times their weight in room temperature ionic liquid RTIL or carbonate solvent. Electrolytes were studied that contained varying amounts of RTIL, lithium trifluoromethanesulfonimide LiTFSi, and alumina nanoparticles. Electrochemical stability of these electrolytes with lithium metal electrodes was studied by galvanic cycling and impedance spectroscopy. Improved cycling stability and decreased interfacial resistance were observed when increasing amounts of RTIL and LiTFSi were added. The addition of small amounts of alumina further decreased interfacial resistance by nearly an order of magnitude. During the course of the study, cycling stability increased from less than 3 to greater than 1000 h at 60 C and 0.25 mA/cm2 current density.

  11. Effects of variation in chain length on ternary polymer electrolyte - Ionic liquid mixture - A molecular dynamics simulation study

    NASA Astrophysics Data System (ADS)

    Raju, S. G.; Hariharan, Krishnan S.; Park, Da-Hye; Kang, HyoRang; Kolake, Subramanya Mayya

    2015-10-01

    Molecular dynamics (MD) simulations of ternary polymer electrolyte - ionic liquid mixtures are conducted using an all-atom model. N-alkyl-N-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide ([CnMPy][TFSI], n = 1, 3, 6, 9) and polyethylene oxide (PEO) are used. Microscopic structure, energetics and dynamics of ionic liquid (IL) in these ternary mixtures are studied. Properties of these four pure IL are also calculated and compared to that in ternary mixtures. Interaction between pyrrolidinium cation and TFSI is stronger and there is larger propensity of ion-pair formation in ternary mixtures. Unlike the case in imidazolium IL, near neighbor structural correlation between TFSI reduces with increase in chain length on cation in both pure IL and ternary mixtures. Using spatial density maps, regions where PEO and TFSI interact with pyrrolidinium cation are identified. Oxygens of PEO are above and below the pyrrolidinium ring and away from the bulky alkyl groups whereas TFSI is present close to nitrogen atom of CnMPy. In pure IL, diffusion coefficient (D) of C3MPy is larger than of TFSI but D of C9MPy and C6MPy are larger than that of TFSI. The reasons for alkyl chain dependent phenomena are explored.

  12. Effect of organic solvents on Li+ ion solvation and transport in ionic liquid electrolytes: a molecular dynamics simulation study.

    PubMed

    Li, Zhe; Borodin, Oleg; Smith, Grant D; Bedrov, Dmitry

    2015-02-19

    Molecular dynamics simulations of N-methyl-N-propylpyrrolidinium (pyr13) bis(trifluoromethanesulfonyl)imide (Ntf2) ionic liquid [pyr13][Ntf2] doped with [Li][Ntf2] salt and mixed with acetonitrile (AN) and ethylene carbonate (EC) organic solvents were conducted using polarizable force field. Structural and transport properties of ionic liquid electrolytes (ILEs) with 20 and 40 mol % of organic solvents have been investigated and compared to properties of neat ILEs. Addition of AN and EC solvents to ILEs resulted in the partial displacement of the Ntf2 anions from the Li(+) first coordination shell by EC and AN and shifting the Li-Ntf2 coordination from bidentate to monodentate. The presence of organic solvents in ILE has increased the ion mobility, with the largest effect observed for the Li(+) cation. The Li(+) conductivity has doubled with addition of 40 mol % of AN. The Li(+)-N(Ntf2) residence times were dramatically reduced with addition of solvents, indicating an increasing contribution from structural diffusion of the Li(+) cations.

  13. Fast ionic conduction in tetravalent metal pyrophosphate-alkali carbonate composites: New potential electrolytes for intermediate-temperature fuel cells

    NASA Astrophysics Data System (ADS)

    Singh, Bhupendra; Bhardwaj, Aman; Gautam, Sandeep K.; Kumar, Devendra; Parkash, Om; Kim, In-Ho; Song, Sun-Ju

    2017-03-01

    Here we present a report on synthesis and characterization of tetravalent metal pyrophosphate (TMP) and alkali carbonate (A2CO3; A = Li and/or Na) composites. The TMP-carbonate composites are prepared by mixing indium-doped tin pyrophosphate or yttrium-doped zirconium pyrophosphate with Li2CO3 or an eutectic mixture of Li2CO3-Na2CO3 in different wt.% ratios. The phase composition, microstructure and electrical conductivity of the sintered specimen are analyzed. In addition, the effect of different TMP and A2CO3 phases is investigated. A maximum ionic conductivity of 5.5 × 10-2 S cm-1 at 630 °C is observed in this study with a Sn0.9In0.1P2O7-Li2CO3 composite. Based on the literature data, TMP-carbonate composites can be considered to be primarily a proton and oxygen-ion co-ionic conductor and, therefore, have strong potential as electrolytes in fuel cells in 500-700 °C range.

  14. Process for the regeneration of metallic catalysts

    DOEpatents

    Katzer, James R.; Windawi, Hassan

    1981-01-01

    A method for the regeneration of metallic hydrogenation catalysts from the class consisting of Ni, Rh, Pd, Ir, Pt and Ru poisoned with sulfur, with or without accompanying carbon deposition, comprising subjecting the catalyst to exposure to oxygen gas in a concentration of about 1-10 ppm. intermixed with an inert gas of the group consisting of He, A, Xe, Kr, N.sub.2 and air substantially free of oxygen to an extent such that the total oxygen molecule throughout is in the range of about 10 to 20 times that of the hydrogen sulfide molecular exposure producing the catalyst poisoning while maintaining the temperature in the range of about 300.degree. to 500.degree. C.

  15. Structure and properties of Li-ion conducting polymer gel electrolytes based on ionic liquids of the pyrrolidinium cation and the bis(trifluoromethanesulfonyl)imide anion

    NASA Astrophysics Data System (ADS)

    Pitawala, Jagath; Navarra, Maria Assunta; Scrosati, Bruno; Jacobsson, Per; Matic, Aleksandar

    2014-01-01

    We have investigated the structure and physical properties of Li-ion conducting polymer gel electrolytes functionalized with ionic liquid/lithium salt mixtures. The membranes are based on poly(vinylidene fluoride-co-hexafluoropropylene) copolymer, PVdF-HFP, and two ionic liquids: pyrrolidinium cations, N-butyl-N-methylpyrrolidinium (PyR14+), N-butyl-N-ethylpyrrolidinium (PyR24+), and bis(trifluoromethanesulfonyl)imide anion (TFSI). The ionic liquids where doped with 0.2 mol kg-1 LiTFSI. The resulting membranes are freestanding, flexible, and nonvolatile. The structure of the polymer and the interactions between the polymer and the ionic liquid electrolyte have been studied using Raman spectroscopy. The ionic conductivity of the membranes has been studied using dielectric spectroscopy whereas the thermal properties were investigated using differential scanning caloriometry (DSC). These results show that there is a weak, but noticeable, influence on the physical properties of the ionic liquid by the confinement in the membrane. We observe a change in the Li-ion coordination, conformation of the anion, the fragility and a slight increase of the glass transition temperatures for IL/LiTFSI mixtures in the membranes compared to the neat mixtures. The effect can be related to the confinement of the liquid in the membrane and/or to interactions with the PVdF-HFP polymer matrix where the crystallinity is decreased compared to the starting polymer powder.

  16. Deer antler regeneration: a stem cell-based epimorphic process.

    PubMed

    Li, Chunyi

    2012-03-01

    Full regeneration of deer antlers, a bona fide epimorphic process in mammals, is in defiance of the general rule of nature. Revealing the mechanism underlying this unique exception would place us in a better position to promote organ regeneration in humans. Antler regeneration takes place in yearly cycles from its pedicle, a permanent protuberance on the frontal bone. Both growing antlers and pedicles consist of internal (cartilage and bone) and external components (skin, blood vessels, and nerves). Recent studies have demonstrated that the regeneration of both internal and external components relies on the presence of pedicle periosteum (PP). PP cells express key embryonic stem cell markers (Oct4, Nanog, and SOX2) and are multipotent, so are termed antler stem cells. Now it is clear that proliferation and differentiation of PP cells directly forms internal antler components; however, how PP initiates and maintains the regeneration of external antler components is thus far not known. Based on the direct as well as indirect evidence that is presented in this review, I put forward the following hypothesis to address this issue. The full regenerative ability of external antler tissue components is achieved through PP-derived chemical induction and PP-derived mechanical stimulation: the former triggers the regeneration of these external components, whereas the latter drives their rapid elongation. Eventual identification of the putative PP-derived chemical factors would open up a new avenue for devising effective therapies for lesions involving each of these tissue components, be they traumatic, degenerative, or linked to developmental (genetic) anomalies.

  17. Criticality and phase behavior in the restricted-primitive model electrolyte: Effect of ionic association

    SciTech Connect

    Jiang, Jianwen; Blum, Lesser; Bernard, Oliver; Prausnitz, John M.

    2001-11-01

    Ion association is incorporated into the restricted-primitive model (RPM) electrolyte to account for the strong attraction between unlike ions. Two methods are investigated within the McMillan-Mayer framework: first is the binding mean-spherical approximation (BIMSA) based on the Wertheim Ornstein-Zernike integral equation formalism; and the second is the combination of the BIMSA with a simple interpolation scheme (SIS) based on the Wertheim thermodynamic perturbation theory. The latter gives a better description. Four different association constants are used to calculate the degree of dissociation, the critical point and the vapor-liquid coexistence curve. An increase in the association constant leads to a lower critical temperature and a higher critical density, and better agreement with computer simulations. When unlike ions are fully paired, corresponding to a charged hard dumbbell (CHDB) system, we obtain the best agreement with the most recent computer simulations of the RPM electrolyte.

  18. Visualization of Biomass Solubilization and Cellulose Regeneration during Ionic Liquid Pretreatment of Switchgrass

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Auto-fluorescent mapping of plant cell walls was used to visualize cellulose and lignin in pristine switchgrass (Panicum virgatum) stems to determine the mechanisms of biomass dissolution during ionic liquid pretreatment. The addition of ground switchgrass to the ionic liquid 1-n-ethyl-3-methylimid...

  19. Nano-Sponge Ionic Liquid-Polymer Composite Electrolytes for Solid-State Lithium Power Sources

    DTIC Science & Technology

    2010-01-01

    images of these solid thin films indicate that these polymer gel electrolytes have the structure of nano-sponges, with a sub-micron pore size. For these... thin film batteries, 150 charge–discharge cycles are run for LixCoO2 where x is cycled between 0.95 down to 0.55. Minimal internal resistance effects...9702;C; exhibiting a significant advancement in the safety of lithium batteries. Atomic force microscopy images of these solid thin films indicate

  20. New fabrication process of long-life dye-sensitized solar cells by in situ gelation of quasi-solid polymer electrolytes

    NASA Astrophysics Data System (ADS)

    Chen, Kuei-Fu; Liu, Chien-Hung; Hsieh, Chien-Kuo; Lin, Cian-Li; Huang, Hsin-Kai; Tsai, Chuen-Horng; Chen, Fu-Rong

    2014-02-01

    Leakage of liquid electrolyte and damage to dye-sensitized solar devices due to ultraviolet irradiation typically result in the poor long-term stability of liquid-electrolyte-based dye-sensitized solar cells (DSSCs). In this study, a simple in situ gelation (ISG) process is developed for the quasi-solid-state electrolyte (QSE) in DSSCs using polyvinyl butyral (PVB), a polymer used worldwide in laminated glass. The diffusion coefficients and ionic conductivities of the QSEs are analyzed, and the optimal ionic conductivity is found to be approximately 2.64 × 10-3 S cm-1, which is approximately six orders of magnitude higher than that of the original PVB thin film. The ISG-QSE devices exhibit a high conversion efficiency of 4.86% at 100 mW cm-2; this is approximately 98% of the efficiency of corresponding liquid electrolyte (LSE) cells. Moreover, the devices can maintain a remarkable 98% of their original efficiency after 2100 working hours owing to the addition of 5% UV absorber to the ISG electrolyte. In addition, the ISG-electrolyte-based DSSCs can drive a 5 × 5 cm2 electrochromic (EC) device, demonstrating the potential for the application of this combination in "smart windows" in the future.

  1. Allylic ionic liquid electrolyte-assisted electrochemical surface passivation of LiCoO2 for advanced, safe lithium-ion batteries

    NASA Astrophysics Data System (ADS)

    Mun, Junyoung; Yim, Taeeun; Park, Jang Hoon; Ryu, Ji Heon; Lee, Sang Young; Kim, Young Gyu; Oh, Seung M.

    2014-08-01

    Room-temperature ionic liquid (RTIL) electrolytes have attracted much attention for use in advanced, safe lithium-ion batteries (LIB) owing to their nonvolatility, high conductivity, and great thermal stability. However, LIBs containing RTIL-electrolytes exhibit poor cyclability because electrochemical side reactions cause problematic surface failures of the cathode. Here, we demonstrate that a thin, homogeneous surface film, which is electrochemically generated on LiCoO2 from an RTIL-electrolyte containing an unsaturated substituent on the cation (1-allyl-1-methylpiperidinium bis(trifluoromethanesulfonyl)imide, AMPip-TFSI), can avert undesired side reactions. The derived surface film comprised of a high amount of organic species from the RTIL cations homogenously covered LiCoO2 with a <25 nm layer and helped suppress unfavorable thermal reactions as well as electrochemical side reactions. The superior performance of the cell containing the AMPip-TFSI electrolyte was further elucidated by surface, electrochemical, and thermal analyses.

  2. Allylic ionic liquid electrolyte-assisted electrochemical surface passivation of LiCoO2 for advanced, safe lithium-ion batteries

    PubMed Central

    Mun, Junyoung; Yim, Taeeun; Park, Jang Hoon; Ryu, Ji Heon; Lee, Sang Young; Kim, Young Gyu; Oh, Seung M.

    2014-01-01

    Room-temperature ionic liquid (RTIL) electrolytes have attracted much attention for use in advanced, safe lithium-ion batteries (LIB) owing to their nonvolatility, high conductivity, and great thermal stability. However, LIBs containing RTIL-electrolytes exhibit poor cyclability because electrochemical side reactions cause problematic surface failures of the cathode. Here, we demonstrate that a thin, homogeneous surface film, which is electrochemically generated on LiCoO2 from an RTIL-electrolyte containing an unsaturated substituent on the cation (1-allyl-1-methylpiperidinium bis(trifluoromethanesulfonyl)imide, AMPip-TFSI), can avert undesired side reactions. The derived surface film comprised of a high amount of organic species from the RTIL cations homogenously covered LiCoO2 with a <25 nm layer and helped suppress unfavorable thermal reactions as well as electrochemical side reactions. The superior performance of the cell containing the AMPip-TFSI electrolyte was further elucidated by surface, electrochemical, and thermal analyses. PMID:25168309

  3. A self-regenerable soot sensor with a proton-conductive thin electrolyte and a nanostructured platinum sensing electrode

    PubMed Central

    Lv, Peiling; Ito, Takenori; Oogushi, Akihide; Nakashima, Kensaku; Nagao, Masahiro; Hibino, Takashi

    2016-01-01

    In recent years, exhaust sensors have become increasingly attractive for use in energy and environmental technologies. Important issues regarding practical applications of these sensors, especially for soot measurements, include the further development of ion-conductive electrolytes and active electrode catalysts for meeting performance and durability requirements. Herein, we design a proton conductor with a high breakdown voltage and a sensing electrode with high sensitivity to electrochemical carbon oxidation, enabling continuous soot monitoring with self-regeneration of the sensor. A Si0.97Al0.03HxP2O7-δ layer with an excellent balance between proton conductivity and voltage endurance was grown on the surface of a Si0.97Al0.03O2-δ substrate by reacting it with liquid H3PO4 at 600 °C. Specific reactivity of the electrochemically formed active oxygen toward soot was accomplished by adding a Pt-impregnated Sn0.9In0.1HxP2O7-δ catalyst into a Pt sensing electrode. To make the best use of these optimized materials, a unipolar electrochemical device was fabricated by configuring the sensing and counter electrodes on the same surface of the electrolyte layer. The resulting amperometric mode sensor successfully produced a current signal that corresponded to the quantity of soot. PMID:27857193

  4. A self-regenerable soot sensor with a proton-conductive thin electrolyte and a nanostructured platinum sensing electrode

    NASA Astrophysics Data System (ADS)

    Lv, Peiling; Ito, Takenori; Oogushi, Akihide; Nakashima, Kensaku; Nagao, Masahiro; Hibino, Takashi

    2016-11-01

    In recent years, exhaust sensors have become increasingly attractive for use in energy and environmental technologies. Important issues regarding practical applications of these sensors, especially for soot measurements, include the further development of ion-conductive electrolytes and active electrode catalysts for meeting performance and durability requirements. Herein, we design a proton conductor with a high breakdown voltage and a sensing electrode with high sensitivity to electrochemical carbon oxidation, enabling continuous soot monitoring with self-regeneration of the sensor. A Si0.97Al0.03HxP2O7-δ layer with an excellent balance between proton conductivity and voltage endurance was grown on the surface of a Si0.97Al0.03O2-δ substrate by reacting it with liquid H3PO4 at 600 °C. Specific reactivity of the electrochemically formed active oxygen toward soot was accomplished by adding a Pt-impregnated Sn0.9In0.1HxP2O7-δ catalyst into a Pt sensing electrode. To make the best use of these optimized materials, a unipolar electrochemical device was fabricated by configuring the sensing and counter electrodes on the same surface of the electrolyte layer. The resulting amperometric mode sensor successfully produced a current signal that corresponded to the quantity of soot.

  5. Bio-electrolytic sensor for rapid monitoring of volatile fatty acids in anaerobic digestion process.

    PubMed

    Jin, Xiangdan; Li, Xiaohu; Zhao, Nannan; Angelidaki, Irini; Zhang, Yifeng

    2017-03-15

    This study presents an innovative biosensor that was developed on the basis of a microbial electrolysis cell for fast and reliable measurement of volatile fatty acids (VFA) during anaerobic digestion (AD) process. The bio-electrolytic sensor was first tested with synthetic wastewater containing varying concentrations of VFA. A linear correlation (R(2) = 0.99) between current densities (0.03 ± 0.01 to 2.43 ± 0.12 A/m(2)) and VFA concentrations (5-100 mM) was found. The sensor performance was then investigated under different affecting parameters such as the external voltage, VFA composition ratio, and ionic strength. Linear relationship between the current density and VFA concentrations was always observed. Furthermore, the bio-electrolytic sensor proved ability to handle interruptions such as the presence of complex organic matter, anode exposure to oxygen and low pH. Finally, the sensor was applied to monitor VFA concentrations in a lab-scale AD reactor for a month. The VFA measurements from the sensor correlated well with those from GC analysis which proved the accuracy of the system. Since hydrogen was produced in the cathode as byproduct during monitoring, the system could be energy self-sufficient. Considering the high accuracy, short response time, long-term stability and additional benefit of H2 production, this bio-electrolytic sensor could be a simple and cost-effective method for VFA monitoring during AD and other anaerobic processes.

  6. Fuel Cells Using the Protic Ionic Liquid and Rotator Phase Solid Electrolyte Principles

    DTIC Science & Technology

    2008-02-13

    was obtained from Alfa Aesar. Anhydrous difluorophosphoric acid was obtained from SynQuest Labs Inc. Anhydrous formic acid (HFm, 98%) was obtained from...monoprotonated salt of hydrazine and formic acid . Viscosities. The viscosities measured on these liquids, shown in Figure 6 for the same representative series as...concept of ionic liquids, formed by proton transfer from Bronsted acid to Bronsted base, serving as the proton transport media in fuel cells is evaluated

  7. Aerospace Power Scholarly Research Program. Delivery Order 0011: Single Ionic Conducting Polymer Electrolyte

    DTIC Science & Technology

    2005-12-01

    crystalline forms were modeled at 300 K and lithium ion self- diffusion coefficients and ionic conductivities were calculated . These calculated ...assembled and used to demonstrate charging and discharging behavior by way of slow scan cyclic voltammetry . Although proof of concept has been shown, the...However, these calculated results reflect ion movement via self- diffusion as determined by the field created by the self-assembly of Li2Pc molecules

  8. A mixture of triethylphosphate and ethylene carbonate as a safe additive for ionic liquid-based electrolytes of lithium ion batteries

    NASA Astrophysics Data System (ADS)

    Lalia, Boor Singh; Yoshimoto, Nobuko; Egashira, Minato; Morita, Masayuki

    A binary mixture of triethylphosphate (TEP) and ethylene carbonate (EC) has been examined as a new non-flammable additive for ionic liquid-based electrolytes for lithium-ion batteries. The optimized electrolyte composition consists of 0.6 mol dm -3 (=M) LiTFSI in PP13TFSI mixed with TEP and EC in volume ratio of 80:10:10, where TFSI and PP13 denote bis(trifluoromethanesulfonyl)imide and N-methyl- N-propylpiperidinium, respectively. The ionic conductivity of PP13TFSI dissolving 0.4 M LiTFSI was improved from 8.2 × 10 -4 S cm -1 to 3.5 × 10 -3 S cm -1 (at 20 °C) with the addition of TEP and EC. The electrochemical behavior of 0.4 M LiTFSI/PP13TFSI with and without TEP and EC was studied by cyclic voltammetry, which showed no deteriorating effect by the addition of TEP and EC on the electrochemical window of PP13TFSI. The flammability of the electrolyte was tested by a direct flame test. The proposed ionic liquid-based electrolyte revealed significant improvements in the electrochemical charge-discharge characteristics for both graphite negative and LiMn 2O 4 positive electrodes.

  9. Thermal, mechanical and ionic conductive behaviour of gamma-radiation induced PEO/PVDF(SIN)-LiClO 4 polymer electrolyte system

    NASA Astrophysics Data System (ADS)

    Song, Yongxian; Wu, Shuyun; Jing, Xiabing; Sun, Jiazhen; Chen, Donglin

    1997-05-01

    An effort has been made to modify the mechanical behaviour of our previously reported gel-type gamma-radiation crosslinked polyethylene oxide (PEO)-LiClO 4 polymer electrolyte. A highly polar and gamma-radiation crosslinkable crystalline polymer, polyvinylidene fluoride (PVDF), was selected to blend with PEO and then subjected to gamma-irradiation in order to make an simultaneous interpenetrating network (SIN), which was used as a polymer host to impart stiffness to the plasticized system. Experimental results have shown that the presence of PVDF in the system, through gamma-radiation induced SIN formation, could not only give a rather high mechanical modulus of 10 7 Pa at ambient temperature, but also maintain the room temperature ionic conductivity at a high level (greater than 10 -4 S/cm). DSC, DMA and conductivity measurement techniques were used to examine the effects of blending, gamma-irradiation and plasticization on the variations of glass transition and melting endotherm, on the appearance of high elastic plateau and on the temperature dependence of ionic conductivity. In addition, it was found that, in contrast with the unplasticized system, the ionic conductivity mechanism of this gel-type electrolyte seems to conform to the Arrhenius model, suggesting that, as a result of the high degree of plasticization, the polymer chains act mainly as the skeleton of the networks or polymer cages to immobilize the liquid electrolyte solution, whereas the ionic species migrate as if they were in a liquid medium.

  10. Thermal regeneration of an electrochemical concentration cell

    DOEpatents

    Krumpelt, M.; Bates, J.K.

    1980-05-09

    A system and method are described for thermally regenerating an electrochemical concentration cell having first and second aluminum electrodes respectively positioned in contact with first and second electrolytes separated by an ion exchange member, the first and second electrolytes being composed of different concentrations of an ionic solvent and a salt, preferably an aluminum halide. The ionic solvent may be either organic or inorganic with a relatively low melting point, the ionic solvent and the salt form a complex wherein the free energy of formation of said complex is less than about -5 kcal/mole. A distillation column using solar heat or low grade industrial waste heat receives the first and second electrolytes and thermally decomposes the salt-solvent complex to provide feed material for the two half cells.

  11. Thermal regeneration of an electrochemical concentration cell

    DOEpatents

    Krumpelt, Michael; Bates, John K.

    1981-01-01

    A system and method for thermally regenerating an electrochemical concentration cell having first and second aluminum electrodes respectively positioned in contact with first and second electrolytes separated by an ion exchange member, the first and second electrolytes being composed of different concentrations of an ionic solvent and a salt, preferably an aluminum halide. The ionic solvent may be either organic or inorganic with a relatively low melting point, the ionic solvent and the salt form a complex wherein the free energy of formation of said complex is less than about -5 Kcal/mole. A distillation column using solar heat or low grade industrial waste heat receives the first and second electrolytes and thermally decomposes the salt-solvent complex to provide feed material for the two half cells.

  12. Ionometric methods used in process control of noble metal plating electrolytes

    SciTech Connect

    Ermolaeva, M.N.; Grekovich, A.L.; Vinogradova, V.P.

    1995-11-01

    Ion-selective electrodes used for the analysis of gold in citrate and cyanide gold plating electrolytes and of silver and cyanide ions in silver plating electrolytes are described. Methods for process control of dicyanoaurate, dicyanoargentate, and cyanide ions in plating electrolytes used in jewelry manufacturing, are presented.

  13. Excitation processes at the electrolyte-electrode interface

    NASA Astrophysics Data System (ADS)

    Zeković, Lj. D.; Urošević, V. V.; Panić, B. M.

    1980-12-01

    This work is concerned with the investigation of galvanoluminescence at the interface metal-oxide-electrolyte during DC anodization of very pure aluminum foils in boric acid-borax solution at constant current. The rate of anodic film formation, the quantitative relations between anode voltage and luminescence intensity as well as the shape of optical emission spectra at different voltages are obtained for annealed and unannealed Al samples. It is found that the previous thermal treatment has great influence on anodization and luminescence processes.

  14. Effect of a pyrrolidinium zwitterion on charge/discharge cycle properties of Li/LiCoO2 and graphite/Li cells containing an ionic liquid electrolyte

    NASA Astrophysics Data System (ADS)

    Yamaguchi, Seitaro; Yoshizawa-Fujita, Masahiro; Takeoka, Yuko; Rikukawa, Masahiro

    2016-11-01

    Ionic liquids (ILs) containing zwitterions have been studied as electrolytes for lithium-ion batteries (LIBs). The effects of addition of a pyrrolidinium zwitterion in an IL electrolyte on the thermal and electrochemical stability and charge/discharge properties of Li/LiCoO2 and graphite/Li cells were investigated. The thermal decomposition temperature of the IL electrolyte composed of N-methyl-N-propylpyrrolidinium bis(fluorosulfonyl)amide ([P13][FSA])/lithium bis(trifluoromethylsulfonyl)amide (LiTFSA) with 3-(1-butylpyrrolidinium)propane-1-sulfonate (Bpyps) as the zwitterionic additive, the thermal decomposition temperature was about 300 °C. The electrochemical window of [P13][FSA]/LiTFSA/Bpyps was 0-+5.4 V vs. Li/Li+, which was almost identical to that of [P13][FSA]/LiTFSA. Li|electrolyte|LiCoO2 cells containing the IL/Bpyps electrolyte system exhibited high capacities in the cut-off voltage range of 3.0-4.6 V, even after 50 cycles. The increase in the interfacial resistance between the electrolyte and cathode with cycling was suppressed. In the cyclic voltammograms of cells employing a graphite electrode, the intercalation/deintercalation of lithium ions were observed in the range of 0 and + 0.4 V vs. Li/Li+. Further, graphite|electrolyte|Li cells containing [P13][FSA]/LiTFSA/Bpyps exhibited stable charge/discharge cycle behaviour over 50 cycles.

  15. Lunar Oxygen Production and Metals Extraction Using Ionic Liquids

    NASA Technical Reports Server (NTRS)

    Marone, Matthew; Paley, Mark Steven; Donovan, David N.; Karr, Laurel J.

    2009-01-01

    Initial results indicate that ionic liquids are promising media for the extraction of oxygen from lunar regolith. IL acid systems can solubilize regolith and produce water with high efficiency. IL electrolytes are effective for water electrolysis, and the spent IL acid media are capable of regeneration.

  16. Enhanced ionic conductivity and optical studies of plasticized (PEO-KCl) solid polymer electrolytes

    NASA Astrophysics Data System (ADS)

    Chapi, Sharanappa; H, Devendrappa

    2015-06-01

    Solid polymer electrolytes (SPEs) based on Polyethylene oxide (PEO) doped with potassium chloride (KCl) were prepared by the solution cast technique. The conductivity increases from 10-10 to 10-6 Scm-1 at 303K with dopant. Optical absorption study shows that the direct & indirect optical band gaps were found decreased from 5.45-4.46eV and 4.96-3.86eV respectively with increasing the KCl. The XRD patterns reveal increasing the amorphous with increasing the dopent. The obtained results suggest that, these polymer systems are suitable candidates for solid state battery, electro chromic devices & optoelectronics display etc.

  17. Natural regeneration processes in big sagebrush (Artemisia tridentata)

    USGS Publications Warehouse

    Schlaepfer, Daniel R.; Lauenroth, William K.; Bradford, John B.

    2014-01-01

    Big sagebrush, Artemisia tridentata Nuttall (Asteraceae), is the dominant plant species of large portions of semiarid western North America. However, much of historical big sagebrush vegetation has been removed or modified. Thus, regeneration is recognized as an important component for land management. Limited knowledge about key regeneration processes, however, represents an obstacle to identifying successful management practices and to gaining greater insight into the consequences of increasing disturbance frequency and global change. Therefore, our objective is to synthesize knowledge about natural big sagebrush regeneration. We identified and characterized the controls of big sagebrush seed production, germination, and establishment. The largest knowledge gaps and associated research needs include quiescence and dormancy of embryos and seedlings; variation in seed production and germination percentages; wet-thermal time model of germination; responses to frost events (including freezing/thawing of soils), CO2 concentration, and nutrients in combination with water availability; suitability of microsite vs. site conditions; competitive ability as well as seedling growth responses; and differences among subspecies and ecoregions. Potential impacts of climate change on big sagebrush regeneration could include that temperature increases may not have a large direct influence on regeneration due to the broad temperature optimum for regeneration, whereas indirect effects could include selection for populations with less stringent seed dormancy. Drier conditions will have direct negative effects on germination and seedling survival and could also lead to lighter seeds, which lowers germination success further. The short seed dispersal distance of big sagebrush may limit its tracking of suitable climate; whereas, the low competitive ability of big sagebrush seedlings may limit successful competition with species that track climate. An improved understanding of the

  18. Filler effect of ionic liquid attached titanium oxide on conducting property of poly(ethylene oxide)/poly(methyl methacrylate) composite electrolytes.

    PubMed

    Lee, Lyungyu; Kim, Ick-Jun; Yang, Sunhye; Kim, Seok

    2014-10-01

    Composite polymer electrolytes (CPEs) were prepared by containing blend of poly(ethylene oxide) (PEO) and poly(methyl methacrylate) (PMMA) as a host polymer, propylene carbonate as a plasticizer, and LiClO4 as a salt. By an addition of a various content of ionic liquid attached TiO2 (IL-TiO2) to above electrolytes, the effects were studied. As a result, by increasing the IL-TiO2 content, the crystallinity of PEO was decreased and the ionic conductivity was increased. The ionic conductivity of CPEs was dependent on the content of IL-TiO2 and showed the highest value of 1.05 x 10(-4) S/cm at 9 wt.%. However, when IL-TiO2 content exceeds 9 wt.%, the ionic conductivity was decreased due to the slow ionic transport due to immiscibility or aggregation of the IL-TiO2 filler within the polymer film matrix.

  19. Computational modeling of the structure and the ionic conductivity of the solid electrolyte materials Li3AsS4 and its Ge substitutions

    NASA Astrophysics Data System (ADS)

    Al-Qawasmeh, Ahmad; Holzwarth, N. A. W.

    Oak Ridge National Laboratory (G. Sahu et al.) reported that the substitution of Ge into Li3AsS4 leads to the composition Li3.334Ge0.334As0.666S4 with impressively high ionic conductivity . We use ab initio calculations to examine the structural relationships and the ionic conductivity mechanisms for pure Li3AsS4, Li3.334Ge0.334As0.666S4, and other compositions of these electrolytes. Supported by NSF Grant DMR-1105485 and 1507942 and WFU's DEAC cluster.

  20. Pyrochemical process for extracting plutonium from an electrolyte salt

    DOEpatents

    Mullins, L.J.; Christensen, D.C.

    1982-09-20

    A pyrochemical process for extracting plutonium from a plutonium-bearing salt is disclosed. The process is particularly useful in the recovery of plutonium for electrolyte salts which are left over from the electrorefining of plutonium. In accordance with the process, the plutonium-bearing salt is melted and mixed with metallic calcium. The calcium reduces ionized plutonium in the salt to plutonium metal, and also causes metallic plutonium in the salt, which is typically present as finely dispersed metallic shot, to coalesce. The reduced and coalesced plutonium separates out on the bottom of the reaction vessel as a separate metallic phase which is readily separable from the overlying salt upon cooling of the mixture. Yields of plutonium are typically on the order of 95%. The stripped salt is virtually free of plutonium and may be discarded to low-level waste storage.

  1. Pyrochemical process for extracting plutonium from an electrolyte salt

    DOEpatents

    Mullins, Lawrence J.; Christensen, Dana C.

    1984-01-01

    A pyrochemical process for extracting plutonium from a plutonium-bearing salt is disclosed. The process is particularly useful in the recovery of plutonium from electrolyte salts which are left over from the electrorefining of plutonium. In accordance with the process, the plutonium-bearing salt is melted and mixed with metallic calcium. The calcium reduces ionized plutonium in the salt to plutonium metal, and also causes metallic plutonium in the salt, which is typically present as finely dispersed metallic shot, to coalesce. The reduced and coalesced plutonium separates out on the bottom of the reaction vessel as a separate metallic phase which is readily separable from the overlying salt upon cooling of the mixture. Yields of plutonium are typically on the order of 95%. The stripped salt is virtually free of plutonium and may be discarded to low-level waste storage.

  2. High Coulombic efficiency aluminum-ion battery using an AlCl3-urea ionic liquid analog electrolyte.

    PubMed

    Angell, Michael; Pan, Chun-Jern; Rong, Youmin; Yuan, Chunze; Lin, Meng-Chang; Hwang, Bing-Joe; Dai, Hongjie

    2017-01-31

    In recent years, impressive advances in harvesting renewable energy have led to a pressing demand for the complimentary energy storage technology. Here, a high Coulombic efficiency (∼99.7%) Al battery is developed using earth-abundant aluminum as the anode, graphite as the cathode, and a cheap ionic liquid analog electrolyte made from a mixture of AlCl3 and urea in a 1.3:1 molar ratio. The battery displays discharge voltage plateaus around 1.9 and 1.5 V (average discharge = 1.73 V) and yielded a specific cathode capacity of ∼73 mAh g(-1) at a current density of 100 mA g(-1) (∼1.4 C). High Coulombic efficiency over a range of charge-discharge rates and stability over ∼150-200 cycles was easily demonstrated. In situ Raman spectroscopy clearly showed chloroaluminate anion intercalation/deintercalation of graphite (positive electrode) during charge-discharge and suggested the formation of a stage 2 graphite intercalation compound when fully charged. Raman spectroscopy and NMR suggested the existence of AlCl4(-), Al2Cl7(-) anions and [AlCl2·(urea)n](+) cations in the AlCl3/urea electrolyte when an excess of AlCl3 was present. Aluminum deposition therefore proceeded through two pathways, one involving Al2Cl7(-) anions and the other involving [AlCl2·(urea)n](+) cations. This battery is a promising prospect for a future high-performance, low-cost energy storage device.

  3. Low-cost microarray thin-film electrodes with ionic liquid gel-polymer electrolytes for miniaturised oxygen sensing.

    PubMed

    Lee, Junqiao; Silvester, Debbie S

    2016-06-21

    A robust, miniaturised electrochemical gas sensor for oxygen (O2) has been constructed using a commercially available Pt microarray thin-film electrode (MATFE) with a gellified electrolyte containing the room temperature ionic liquid (RTIL) 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([C2mim][NTf2]) and poly(methyl methacrylate) (PMMA) in a 50 : 50 mass ratio. Diffusion coefficients and solubilities for oxygen in mixtures of PMMA/RTIL at different PMMA doping concentrations (0-50% mass) were derived from potential step chronoamperometry (PSCA) on a Pt microdisk electrode. The MATFE was then used with both the neat RTIL and 50% (by mass) PMMA/RTIL gel, to study the analytical behavior over a wide concentration range (0.1 to 100 vol% O2). Cyclic voltammetry (CV) and long-term chronoamperometry (LTCA) techniques were employed and it was determined that the gentler CV technique is better at higher O2 concentrations (above 60 vol%), but LTCA is more reliable and accurate at lower concentrations (especially below 0.5% O2). In particular, there was much less potential shifting (from the unstable Pt quasi-reference electrode) evident in the 50% PMMA/RTIL gel than in the neat RTIL, making this a much more suitable electrolyte for long-term continuous oxygen monitoring. The mass production and low-cost of the electrode array, along with the minimal amounts of RTIL/PMMA required, make this a viable sensing device for oxygen detection on a bulk scale in a wide range of environmental conditions.

  4. Evaluation of the tapered PMMA fiber sensor response due to the ionic interaction within electrolytic solutions

    NASA Astrophysics Data System (ADS)

    Batumalay, M.; Rahman, H. A.; Kam, W.; Ong, Y. S.; Ahmad, F.; Zakaria, R.; Harun, S. W.; Ahmad, H.

    2014-01-01

    A tapered plastic multimode fiber (PMMA) optical sensor is proposed and demonstrated for continuous monitoring of solutions based on different concentration of sodium chloride and glucose in deionized water The tapered PMMA fiber was fabricated using an etching method involving deionized water and acetone to achieve a waist diameter and length of 0.45 mm and 10 mm, respectively, and was used to investigate the effect of straight, U-shape, and knot shape against concentration for both sodium chloride and glucose. The results show that there is a strong dependence of the electrolytic and non-electrolytic nature of the chemical solutions on the sensor output. It is found that the sensitivity of the sodium chloride concentration sensor with the straight tapered fiber probe was 0.0023 mV/%, which was better than the other probe arrangements of U-shape and knot. Meanwhile, the glucose sensor performs with the highest sensitivity of 0.0026 mV/wt % with the knot-shaped tapered fiber probe. In addition, a tapered PMMA probe which was coated by silver film was fabricated and demonstrated using calcium hypochlorite (G70) solution. The working mechanism of such a device is based on the observed increment in the transmission of the sensor that is immersed in solutions of higher concentration. As the concentration varies from 0 ppm to 6 ppm, the output voltage of the sensor increases linearly from 3.61 mV to 4.28 mV with a sensitivity of 0.1154 mV/ppm and a linearity of more than 99.47%. The silver film coating increases the sensitivity of the proposed sensor due to the effective cladding refractive index, which increases with the coating and thus allows more light to be transmitted from the tapered fiber.

  5. Ionic-Liquid-Mediated Extraction and Separation Processes for Bioactive Compounds: Past, Present, and Future Trends.

    PubMed

    Ventura, Sónia P M; E Silva, Francisca A; Quental, Maria V; Mondal, Dibyendu; Freire, Mara G; Coutinho, João A P

    2017-02-02

    Ionic liquids (ILs) have been proposed as promising media for the extraction and separation of bioactive compounds from the most diverse origins. This critical review offers a compilation on the main results achieved by the use of ionic-liquid-based processes in the extraction and separation/purification of a large range of bioactive compounds (including small organic extractable compounds from biomass, lipids, and other hydrophobic compounds, proteins, amino acids, nucleic acids, and pharmaceuticals). ILs have been studied as solvents, cosolvents, cosurfactants, electrolytes, and adjuvants, as well as used in the creation of IL-supported materials for separation purposes. The IL-based processes hitherto reported, such as IL-based solid-liquid extractions, IL-based liquid-liquid extractions, IL-modified materials, and IL-based crystallization approaches, are here reviewed and compared in terms of extraction and separation performance. The key accomplishments and future challenges to the field are discussed, with particular emphasis on the major lacunas found within the IL community dedicated to separation processes and by suggesting some steps to overcome the current limitations.

  6. Charge-storage performance of Li/LiFePO4 cells with additive-incorporated ionic liquid electrolytes at various temperatures

    NASA Astrophysics Data System (ADS)

    Wongittharom, Nithinai; Wang, Chueh-Han; Wang, Yi-Chen; Fey, George Ting-Kuo; Li, Hui-Ying; Wu, Tzi-Yi; Lee, Tai-Chou; Chang, Jeng-Kuei

    2014-08-01

    Butylmethylpyrrolidinium bis(trifluoromethanesulfonyl)imide (BMP-TFSI) ionic liquid (IL) with LiTFSI solute is used as a base electrolyte for Li/LiFePO4 cells. Three kinds of electrolyte additive, namely vinylene carbonate (VC), gamma-butyrolactone (γ-BL), and propylene carbonate (PC), with various concentrations are introduced. The thermal stability, flammability, and electrochemical properties of the electrolytes are investigated. At 25 °C, the additives (γ-BL is found to be the most effective) can significantly improve the capacity, high-rate performance, and cyclability of the cells. With an increase in temperature to 50 °C, the benefits of the additives gradually become insignificant. At 75 °C, the additives even have adverse effects. At such an elevated temperature, in the plain IL electrolyte (without additives), a LiFePO4 capacity of 152 mAh g-1 is found at 0.1 C. 77% of this capacity can be retained when the rate is increased to 3 C. These values are superior to those found for the additive-incorporated IL and conventional organic electrolytes. Moreover, negligible capacity loss is measured after 100 charge-discharge cycles at 75 °C in the plain IL electrolyte.

  7. Ionic liquid hybrids: Progress toward non-corrosive electrolytes with high-voltage oxidation stability for magnesium-ion based batteries

    DOE PAGES

    Huie, Matthew M.; Cama, Christina A.; Smith, Paul F.; ...

    2016-10-01

    Magnesium – ion batteries have the potential for high energy density but require new types of electrolytes for practical application. Ionic liquid (IL) electrolytes offer the opportunity for increased safety and broader voltage windows relative to traditional electrolytes. We present here a systematic study of both the conductivity and oxidative stability of hybrid electrolytes consisting of eleven ILs mixed with dipropylene glycol dimethylether (DPGDME) or acetonitrile (ACN) cosolvents and magnesium bis(trifluoromethylsulfonyl)imide (Mg(TFSI)2). Our study finds a correlation of higher conductivity of ILs with unsaturated rings and short carbon chain lengths, but by contrast, these ILs also exhibited lower oxidation voltagemore » limits. For the cosolvent additive, although glymes have a demonstrated capability of coordination with Mg2+ ions, a decrease in conductivity compared to acetonitrile hybrid electrolytes was observed. Lastly, when cycled within the appropriate voltage range, the IL-hybrid electrolytes that show the highest conductivity provide the best cathode magnesiation current densities and lowest polarization as demonstrated with a Mg0.15MnO2 and Mg0.07V2O5 cathodes.« less

  8. Ionic liquid hybrids: Progress toward non-corrosive electrolytes with high-voltage oxidation stability for magnesium-ion based batteries

    SciTech Connect

    Huie, Matthew M.; Cama, Christina A.; Smith, Paul F.; Yin, Jiefu; Marschilok, Amy C.; Takeuchi, Kenneth J.; Takeuchi, Esther S.

    2016-10-01

    Magnesium – ion batteries have the potential for high energy density but require new types of electrolytes for practical application. Ionic liquid (IL) electrolytes offer the opportunity for increased safety and broader voltage windows relative to traditional electrolytes. We present here a systematic study of both the conductivity and oxidative stability of hybrid electrolytes consisting of eleven ILs mixed with dipropylene glycol dimethylether (DPGDME) or acetonitrile (ACN) cosolvents and magnesium bis(trifluoromethylsulfonyl)imide (Mg(TFSI)2). Our study finds a correlation of higher conductivity of ILs with unsaturated rings and short carbon chain lengths, but by contrast, these ILs also exhibited lower oxidation voltage limits. For the cosolvent additive, although glymes have a demonstrated capability of coordination with Mg2+ ions, a decrease in conductivity compared to acetonitrile hybrid electrolytes was observed. Lastly, when cycled within the appropriate voltage range, the IL-hybrid electrolytes that show the highest conductivity provide the best cathode magnesiation current densities and lowest polarization as demonstrated with a Mg0.15MnO2 and Mg0.07V2O5 cathodes.

  9. Effects of background electrolytes and ionic strength on enrichment of Cd(II) ions with magnetic graphene oxide-supported sulfanilic acid.

    PubMed

    Hu, Xin-jiang; Liu, Yun-guo; Zeng, Guang-ming; You, Shao-hong; Wang, Hui; Hu, Xi; Guo, Yi-ming; Tan, Xiao-fei; Guo, Fang-ying

    2014-12-01

    To elucidate the influence mechanisms of background electrolytes and ionic strength on Cd(II) removal, the adsorption of Cd(II) onto magnetic graphene oxide-supported sulfanilic acid (MGO-SA) in aqueous solutions containing different types and concentrations of background electrolytes was studied. The results indicate that Cd(II) adsorption was strongly dependent on pH and could be strongly affected by background electrolytes and ionic strength. The Cd(II) removal was decreased with the presence of background electrolyte cations (Na(+), K(+), Ca(2+), Mg(2+), Mn(2+), Zn(2+), and Ni(2+)), and the divalent cations exerted more obvious influences on the Cd(II) uptake than the monovalent cations at pH 6. Both Cl(-) and NO3(-) had negative effects on Cd(II) adsorption because they can form water-soluble metal-anion complexes with Cd(II) ions. The presence of 0.01molL(-1) Na3PO4 reduced the removal percentage of Cd(II) at pH<5 but extremely enhanced the Cd(II) removal when the pH>5. The Cd(II) adsorption was sensitive to changes in the concentration of NaCl, NaNO3, NaClO4, and Na3PO4. Besides, the adsorption isotherm of Cd(II) onto MGO-SA could be well described by the Freundlich model and was also influenced by the type of background electrolyte ions and the ionic strength.

  10. Motility recovery during the process of regeneration in freshwater planarians.

    PubMed

    Kato, Chihiro; Mihashi, Koshin; Ishida, Sachiko

    2004-04-02

    Planarians are phylogenetically considered to be the most primitive animals to have acquired a central nervous system and a bilateral symmetry. However, very little is known about the relationship between planarian brain integration and motility. A behavioural and histological study was therefore undertaken in an aspect of planarian motility recovery during its process of regeneration. Quantitative analysis showed that the tail-regenerates recovered their motility gradually as the new heads reformed, while the non-head reforming tail fragments showed no signs of recovery. The head fragments recovered their motility soon after cutting. The cephalic margin was not a function of the motility. The brain regenerated back to its original form in approximately two weeks, the same amount of time it took for the decapitated tails to recover their motility to initial levels. This study provides quantitative evidence that the planarian motility recovered in relation to the head formation during its process of regeneration. Our results reinforce the view that the brain plays a functional part in activating planarian motility.

  11. Ionic Liquid-Organic Carbonate Electrolyte Blends To Stabilize Silicon Electrodes for Extending Lithium Ion Battery Operability to 100 °C.

    PubMed

    Ababtain, Khalid; Babu, Ganguli; Lin, Xinrong; Rodrigues, Marco-Tulio F; Gullapalli, Hemtej; Ajayan, Pulickel M; Grinstaff, Mark W; Arava, Leela Mohana Reddy

    2016-06-22

    Fabrication of lithium-ion batteries that operate from room temperature to elevated temperatures entails development and subsequent identification of electrolytes and electrodes. Room temperature ionic liquids (RTILs) can address the thermal stability issues, but their poor ionic conductivity at room temperature and compatibility with traditional graphite anodes limit their practical application. To address these challenges, we evaluated novel high energy density three-dimensional nano-silicon electrodes paired with 1-methyl-1-propylpiperidinium bis(trifluoromethanesulfonyl)imide (Pip) ionic liquid/propylene carbonate (PC)/LiTFSI electrolytes. We observed that addition of PC had no detrimental effects on the thermal stability and flammability of the reported electrolytes, while largely improving the transport properties at lower temperatures. Detailed investigation of the electrochemical properties of silicon half-cells as a function of PC content, temperature, and current rates reveal that capacity increases with PC content and temperature and decreases with increased current rates. For example, addition of 20% PC led to a drastic improvement in capacity as observed for the Si electrodes at 25 °C, with stability over 100 charge/discharge cycles. At 100 °C, the capacity further increases by 3-4 times to 0.52 mA h cm(-2) (2230 mA h g(-1)) with minimal loss during cycling.

  12. Variations in the spatial distribution of sonoluminescing bubbles in the presence of an ionic surfactant and electrolyte.

    PubMed

    Lee, Judy; Vakarelski, Ivan U; Yasui, Kyuichi; Tuziuti, Toru; Kozuka, Teruyuki; Towata, Atsuya; Iida, Yasuo

    2010-03-04

    It has been established that the addition of sodium dodecylsulfate (SDS) to water to a concentration of 1 mM increased the integrated sonoluminescence (SL) intensity to a maximum. Moreover, further increase in the SDS concentration to 10 mM decreased the SL intensity to a level comparable to that obtained for water. Photographic images of water and 10 mM SDS have revealed a localized distribution of SL bubbles near the liquid surface. For 1 mM SDS, a homogeneous distribution of SL bubbles was observed throughout the liquid. In this study, a comprehensive investigation was performed to determine the variations in the spatial distribution of SL bubbles as a function of SDS concentration, with and without the addition of sodium chloride (NaCl). It was found that the integrated SL intensity passed through a local minimum as the distribution of SL bubbles transformed from an isolated to a homogeneous distribution at 0.25 and 2.4 mM SDS. Similar transformations in the spatial distribution of SL bubbles within these SDS solutions were also observed upon the addition of a few millimolar NaCl. These variations in the spatial distribution of SL bubbles in aqueous solutions containing an ionic surfactant and electrolyte were believed to be the result of changes in the coalescence stability of bubbles, the attenuation of the acoustic wave, and the standing wave ratio.

  13. The influence of cations on lithium ion coordination and transport in ionic liquid electrolytes: a MD simulation study.

    PubMed

    Lesch, Volker; Li, Zhe; Bedrov, Dmitry; Borodin, Oleg; Heuer, Andreas

    2016-01-07

    The dynamical and structural properties in two ionic liquid electrolytes (ILEs) based on 1-ethyl-3-methylimidazolium bis-(trifluoromethanesulfonyl)-imide ([emim][TFSI]) and N-methyl-N-propylpyrrolidinium bis-(trifluoromethanesulfonyl)imide([pyr13][TFSI]) were compared as a function of lithium bis-(trifluoromethanesulfonyl)-imide (LiTFSI) salt concentrations using atomistic molecular dynamics (MD) simulations. The many-body polarizable APPLE&P force field has been utilized. The influence of anion polarization on the structure of the first coordination shell of Li(+) was examined. In particular, the reduction of the oxygen of the TFSI anion (OTFSI) polarizability from 1.36 Å(3) to 1.00 Å(3) resulted in an increased fraction of the TFSI anion bidentate coordination to the Li(+). While the overall dynamics in [pyr13][TFSI]-based ILEs was slower than in [emim][TFSI]-based ILEs, the exchange of TFSI anions in and out of the first coordination shell of Li(+) was found to be faster in pyr13-based systems. The Li(+) ion transference number is higher for these systems as well. These trends can be related to the difference in interaction of TFSI with the IL cation which is stronger for pyr13 than for emim.

  14. Ionic liquid electrolytes with high sodium ion fraction for high-rate and long-life sodium secondary batteries

    NASA Astrophysics Data System (ADS)

    Chen, Chih-Yao; Kiko, Tomohiro; Hosokawa, Takafumi; Matsumoto, Kazuhiko; Nohira, Toshiyuki; Hagiwara, Rika

    2016-11-01

    Sodium secondary batteries are attracting considerably renewed interest as new battery systems owing to the high and uniform abundance and cost advantages of Na. However, their performance is still far from optimal as compared to the well-developed Li-ion technology. Herein, Na secondary batteries with unprecedented rate capability and a long life has been achieved by using a highly concentrated bis(fluorosulfonyl)amide anion (FSA-)-based ionic liquid electrolyte (3.3 mol dm-3 Na[FSA]) and a Na2FeP2O7 positive electrode, in a targeted operating temperature range from room to intermediate. Nearly full discharge capacity is obtained at 4000 mA g-1, and 79% of the capacity is retained at a discharge rate as high as 20000 mA g-1 at 363 K. Stable cycling (>300 cycles) with satisfactory coulombic efficiency (>99.5%) is found at an intermediate rate (100 mA g-1) over 298-363 K. A high-rate cycling test (1000 mA g-1) at 363 K reveals that the cell could retain 93% of its initial capacity after 1500 cycles.

  15. Regeneration of stochastic processes: an inverse method

    NASA Astrophysics Data System (ADS)

    Ghasemi, F.; Peinke, J.; Sahimi, M.; Rahimi Tabar, M. R.

    2005-10-01

    We propose a novel inverse method that utilizes a set of data to construct a simple equation that governs the stochastic process for which the data have been measured, hence enabling us to reconstruct the stochastic process. As an example, we analyze the stochasticity in the beat-to-beat fluctuations in the heart rates of healthy subjects as well as those with congestive heart failure. The inverse method provides a novel technique for distinguishing the two classes of subjects in terms of a drift and a diffusion coefficients which behave completely differently for the two classes of subjects, hence potentially providing a novel diagnostic tool for distinguishing healthy subjects from those with congestive heart failure, even at the early stages of the disease development.

  16. Characterization of cellulose II nanoparticles regenerated from ionic liquid, 1-butyl-3-methylimidazolium chloride

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Regenerated cellulose nanoparticles (RCNs) including both elongated fiber and spherical structures were prepared from microcrystalline cellulose (MCC)and cotton using 1-butyl-3-methylimidazolium chloride followed by high-pressure homogenization. The crystalline structure of RCNs was cellulose II in ...

  17. Harnessing developmental processes for vascular engineering and regeneration.

    PubMed

    Park, Kyung Min; Gerecht, Sharon

    2014-07-01

    The formation of vasculature is essential for tissue maintenance and regeneration. During development, the vasculature forms via the dual processes of vasculogenesis and angiogenesis, and is regulated at multiple levels: from transcriptional hierarchies and protein interactions to inputs from the extracellular environment. Understanding how vascular formation is coordinated in vivo can offer valuable insights into engineering approaches for therapeutic vascularization and angiogenesis, whether by creating new vasculature in vitro or by stimulating neovascularization in vivo. In this Review, we will discuss how the process of vascular development can be used to guide approaches to engineering vasculature. Specifically, we will focus on some of the recently reported approaches to stimulate therapeutic angiogenesis by recreating the embryonic vascular microenvironment using biomaterials for vascular engineering and regeneration.

  18. Harnessing developmental processes for vascular engineering and regeneration

    PubMed Central

    Park, Kyung Min; Gerecht, Sharon

    2014-01-01

    The formation of vasculature is essential for tissue maintenance and regeneration. During development, the vasculature forms via the dual processes of vasculogenesis and angiogenesis, and is regulated at multiple levels: from transcriptional hierarchies and protein interactions to inputs from the extracellular environment. Understanding how vascular formation is coordinated in vivo can offer valuable insights into engineering approaches for therapeutic vascularization and angiogenesis, whether by creating new vasculature in vitro or by stimulating neovascularization in vivo. In this Review, we will discuss how the process of vascular development can be used to guide approaches to engineering vasculature. Specifically, we will focus on some of the recently reported approaches to stimulate therapeutic angiogenesis by recreating the embryonic vascular microenvironment using biomaterials for vascular engineering and regeneration. PMID:25005471

  19. The effects of dication symmetry on ionic liquid electrolytes in supercapacitors

    NASA Astrophysics Data System (ADS)

    Li, Song; Zhu, Mengyang; Feng, Guang

    2016-11-01

    The effects of dication symmetry on the structure and capacitance of the electrical double layers (EDLs) of dicationic ionic liquids (DILs) near graphene electrodes were investigated by molecular dynamics (MD) simulation in this work. Symmetrical 1-hexyl-3-dimethylimidazolium di[bis(trifluoromethyl)imide]([C6(mim)2](Tf2N)2) and asymmetrical 1-(1-trimethylammonium-yl-hexyl)-3-methylimidazolium di[bis(trifluoro-methanesulfonyl)-imide] ([C6(tma)(mim)](Tf2N)2) were both employed. Radial distribution function (RDF) analysis of the two DILs revealed a shorter distance between the cation-anion pairs in symmetrical [C6(mim)2](Tf2N)2), which was attributed to the closely packed imidazolium ring-anion pairs. In contrast, the trimethylammonium head groups and anions exhibit a relatively longer distance, but a stronger correlation in asymmetrical [C6(tma)(mim)](Tf2N)2. In addition, it was illustrated that more symmetrical DIL ions in EDLs are distributed near graphite electrodes and exhibit closer distances to the electrode, which is most probably due to the parallel orientation of imidazolium rings, reducing the distance between the cation and the graphene. In contrast, asymmetrical DILs, with one trimethylammonium head group and one imidazolium ring in the dications, are loosely packed due to their tilting orientation near graphene surfaces. However, the capacitance-potential (C-V) curves of the two DILs are almost the same, regardless of the opposite sign of potential of zero charge (PZC), indicating the insignificant influence of dication symmetry on the capacitance of DIL-based supercapacitors.

  20. Electrolytic treatment of Standard Malaysian Rubber process wastewater.

    PubMed

    Vijayaraghavan, Krishnan; Ahmad, Desa; Yazid, Ahmad Yuzri Ahmad

    2008-01-31

    A new method of Standard Malaysian Rubber (SMR) process wastewater treatment was developed based on in situ hypochlorous acid generation. The hypochlorous acid was generated in an undivided electrolytic cell consisting of two sets of graphite as anode and stainless sheets as cathode. The generated hypochlorous acid served as an oxidizing agent to destroy the organic matter present in the SMR wastewater. For an influent COD concentration of 2960 mg/L at an initial pH 4.5+/-0.1, current density 74.5 mA/cm(2), sodium chloride content 3% and electrolysis period of 75 min, resulted in the following residual values pH 7.5, COD 87 mg/L, BOD(5) 60 mg/L, TOC 65 mg/L, total chlorine 146 mg/L, turbidity 7 NTU and temperature 48 degrees C, respectively. In the case of 2% sodium chloride as an electrolyte for the above said operating condition resulted in the following values namely: pH 7.2, COD 165 mg/L, BOD(5) 105 mg/L, TOC 120 mg/L, total chlorine 120 mg/L, turbidity 27 NTU and temperature 53 degrees C, respectively. The energy requirement were found to be 30 and 46 Wh/L, while treating 24 L of SMR wastewater at 2 and 3% sodium chloride concentration at a current density 74.5 mA/cm(2). The observed energy difference was due to the improved conductivity at high sodium chloride content.

  1. Self-regenerating column chromatography

    DOEpatents

    Park, W.K.

    1995-05-30

    The present invention provides a process for treating both cations and anions by using a self-regenerating, multi-ionic exchange resin column system which requires no separate regeneration steps. The process involves alternating ion-exchange chromatography for cations and anions in a multi-ionic exchange column packed with a mixture of cation and anion exchange resins. The multi-ionic mixed-charge resin column works as a multi-function column, capable of independently processing either cationic or anionic exchange, or simultaneously processing both cationic and anionic exchanges. The major advantage offered by the alternating multi-function ion exchange process is the self-regeneration of the resins.

  2. Morphology control of zinc regeneration for zinc-air fuel cell and battery

    NASA Astrophysics Data System (ADS)

    Wang, Keliang; Pei, Pucheng; Ma, Ze; Xu, Huachi; Li, Pengcheng; Wang, Xizhong

    2014-12-01

    Morphology control is crucial both for zinc-air batteries and for zinc-air fuel cells during zinc regeneration. Zinc dendrite should be avoided in zinc-air batteries and zinc pellets are yearned to be formed for zinc-air fuel cells. This paper is mainly to analyze the mechanism of shape change and to control the zinc morphology during charge. A numerical three-dimensional model for zinc regeneration is established with COMSOL software on the basis of ionic transport theory and electrode reaction electrochemistry, and some experiments of zinc regeneration are carried out. The deposition process is qualitatively analyzed by the kinetics Monte Carlo method to study the morphological change from the electrocrystallization point of view. Morphological evolution of deposited zinc under different conditions of direct currents and pulse currents is also investigated by simulation. The simulation shows that parametric variables of the flowing electrolyte, the surface roughness and the structure of the electrode, the charging current and mode affect morphological evolution. The uniform morphology of deposited zinc is attained at low current, pulsating current or hydrodynamic electrolyte, and granular morphology is obtained by means of an electrode of discrete columnar structure in combination with high current and flowing electrolyte.

  3. Electrochemistry and spectroscopy of electrolytes and cathode materials in room-temperature ionic liquids

    NASA Astrophysics Data System (ADS)

    Ryan, David Martin

    The demonstration of a stable, reversible, alkali metal anode is an important step in the development of practical secondary batteries using room temperature chloroaluminate molten salts as electrolytes. Such melts are made by mixing 1-ethyl-3-methylimidazolium chloride (EMIC) with aluminum chloride, and can be Lewis buffered by adding LiCl or NaCl. It has been shown previously that protons added to a sodium chloride buffered melt as 1-ethyl-3-methyfimidazolium hydrogen dichloride (EMIHCl2) provide a more negative voltage window and nearly reversible deposition-stripping behavior for sodium. It is reported here that triethanolamine hydrogen chloride is effective in widening the voltage window, allows the plating and stripping of both lithium and sodium, and is stable in buffered EMIC/AlCl3 melts for months. It is suggested that deprotonation of one ethanolic group of triethanolamine HCl is responsible for the effect. The electrochemistry and UV-visible spectroscopy of several vanadium oxides have been examined in room temperature melts. By varying the mole ratio of the two components, Lewis basic, neutral and acidic melts were made. Most oxides have very low solubility: V2O4 and V2O3 are insoluble and V2O5 has a solubility limit less than 5 mM, but the solubilities of the salts NaVO 3, Na3VO4, and NH4VO3, VOCl 3 and VOF3 are significantly higher. The electrochemistry of V2O5, NaVO3, Na3VO4, NH4VO3, VOCl3 and VOF3 is similar in neutral and acidic melts. In the neutral melt each compound shows an irreversible reduction at about 0.45V vs. an Al wire reference electrode. In an acidic melt (mole fraction AlCl3 = 0.55) each of these compounds exhibit additional reduction peaks at more positive potentials. Coulometric and spectroscopic data for the 0.45V reduction suggest that mixed oxidation state polyvanadates may be formed. Controlled potential coulometry demonstrated that the reduction at 0.45V was the reduction of V(V) to V(IV) and the more positive reduction peaks

  4. High-Strength Composite Fibers from Cellulose-Lignin Blends Regenerated from Ionic Liquid Solution.

    PubMed

    Ma, Yibo; Asaadi, Shirin; Johansson, Leena-Sisko; Ahvenainen, Patrik; Reza, Mehedi; Alekhina, Marina; Rautkari, Lauri; Michud, Anne; Hauru, Lauri; Hummel, Michael; Sixta, Herbert

    2015-12-07

    Composite fibres that contain cellulose and lignin were produced from ionic liquid solutions by dry-jet wet spinning. Eucalyptus dissolving pulp and organosolv/kraft lignin blends in different ratios were dissolved in the ionic liquid 1,5-diazabicyclo[4.3.0]non-5-enium acetate to prepare a spinning dope from which composite fibres were spun successfully. The composite fibres had a high strength with slightly decreasing values for fibres with an increasing share of lignin, which is because of the reduction in crystallinity. The total orientation of composite fibres and SEM images show morphological changes caused by the presence of lignin. The hydrophobic contribution of lignin reduced the vapour adsorption in the fibre. Thermogravimetric analysis curves of the composite fibres reveal the positive effect of the lignin on the carbonisation yield. Finally, the composite fibre was found to be a potential raw material for textile manufacturing and as a precursor for carbon fibre production.

  5. Two-dimensional ion chromatography for the separation of ionic organophosphates generated in thermally decomposed lithium hexafluorophosphate-based lithium ion battery electrolytes.

    PubMed

    Kraft, Vadim; Grützke, Martin; Weber, Waldemar; Menzel, Jennifer; Wiemers-Meyer, Simon; Winter, Martin; Nowak, Sascha

    2015-08-28

    A two-dimensional ion chromatography (IC/IC) technique with heart-cutting mode for the separation of ionic organophosphates was developed. These analytes are generated during thermal degradation of three different commercially available Selectilyte™ lithium ion battery electrolytes. The composition of the investigated electrolytes is based on 1M lithium hexafluorophosphate (LiPF6) dissolved in ethylene carbonate/dimethyl carbonate (50:50wt%, LP30), ethylene carbonate/diethyl carbonate (50:50wt%, LP40) and ethylene carbonate/ethyl methyl carbonate (50:50wt%, LP50). The organophosphates were pre-separated from PF6(-) anion on the low capacity A Supp 4 column, which was eluted with a gradient step containing acetonitrile. The fraction containing analytes was retarded on a pre-concentration column and after that transferred to the high capacity columns, where the separation was performed isocratically. Different stationary phases and eluents were applied on the 2nd dimension for the investigation of retention times, whereas the highly promising results were obtained with a high capacitive A Supp 10 column. The organophosphates generated in LP30 and LP40 electrolytes could be separated by application of an aqueous NaOH eluent providing fast analysis time within 35min. For the separation of the organophosphates of LP50 electrolyte due to its complexity a NaOH eluent containing a mixture of methanol/H2O was necessary. In addition, the developed two dimensional IC method was hyphenated to an inductively coupled plasma mass spectrometer (ICP-MS) using aqueous NaOH without organic modifiers. This proof of principle measurement was carried out for future quantitative investigation regarding the concentration of the ionic organophosphates. Furthermore, the chemical stability of several ionic organophosphates in water and acetonitrile at room temperature over a period of 10h was investigated. In both solvents no decomposition of the investigated analytes was observed and

  6. Effect of LiNO3 additive and pyrrolidinium ionic liquid on the solid electrolyte interphase in the lithium-sulfur battery

    NASA Astrophysics Data System (ADS)

    Barghamadi, Marzieh; Best, Adam S.; Bhatt, Anand I.; Hollenkamp, Anthony F.; Mahon, Peter J.; Musameh, Mustafa; Rüther, Thomas

    2015-11-01

    The lithium-sulfur (Li-S) battery in which the ionic liquid (IL) C4mpyr-TFSI is a major component of the electrolyte has attracted much attention by researchers due to the ability of the IL to suppress the polysulfide shuttle effect, combined with advantageous properties of thermal, chemical and electrochemical stability. In a largely parallel stream of research, LiNO3 has come to be known as an additive for improving Li-S battery performance through its influence on protecting the lithium anode and beneficial interaction with the polysulfide shuttle. In this work a deeper understanding is sought of the combined effects of LiNO3 and C4mpyr-TFSI on the factors that impact Li-S cell performance. Specifically, we investigate the formation of the protective surface film on lithium anode and results are compared with those for a typical organic electrolyte for the Li-S battery, DOL:DME. Electrochemical impedance spectroscopy (EIS) confirms that the LiNO3 additive is vital to achieving acceptable levels of performance with the organic electrolyte. Although LiNO3 improves the performance of a battery assembled with IL containing electrolyte, it shows a higher impact in the organic electrolyte based battery. Furthermore X-ray photoelectron spectroscopy (XPS) spectra confirm the participation of C4mpyr-TFSI on the formation of the interphase layer on the anode.

  7. Electrochemically stable electrolytes

    DOEpatents

    Angell, C.A.; Zhang, S.S.; Xu, K.

    1999-01-05

    This invention relates generally to inorganic ionic liquids which function as electrolytes and do not crystallize at ambient temperature. More specifically, this invention is directed to quasi-salt inorganic ionic liquids which comprise the reaction product of a strong Lewis acid with an inorganic halide-donating molecule. This invention is further directed to quasi-salt inorganic ionic liquid mixtures which comprise combinations of electrolyte additives and quasi-salt inorganic ionic liquids. These quasi-salt inorganic ionic liquid mixtures are useful electrolytes. 16 figs.

  8. Unconventional processes for food regeneration in space - An overview

    NASA Technical Reports Server (NTRS)

    Stokes, B. O.; Petersen, G. R.; Schubert, W. W.; Mueller, W. A.

    1981-01-01

    Alternatives to conventional plant agriculture for the regeneration of food during space missions of extended duration are examined. The options considered, which may be used in combination with conventional agriculture, include the production of food from plant wastes, the chemical synthesis of food from carbon dioxide and other simple molecules or the substitution of edible chemicals, and the use of microrganisms for food and oxygen regeneration, with suitable processing. A comparison of solar energy conversion efficiencies is presented for nonphotosynthetic bacteria grown on hydrogen and algal systems photosynthetically, and it is shown that hydrogen bacteria are potentially more attractive than photosynthetic algae using artificial light. Weight-volume requirements for the conventional plant, algae and hydrogen bacteria systems are also compared to demonstrate the advantages of microbial systems.

  9. Effect of Temperature and Pressure on Ionic Conductivity of PAN-Based Polymer Electrolytes Containing Inorganic Salts

    NASA Astrophysics Data System (ADS)

    Ahmad, A.; Isa, K. B. Md.; Osman, Z.

    2010-07-01

    The conducting polymer electrolyte films consisting polyacrylonitrile (PAN) as the host polymer, ethylene carbonate (EC) as a plasticizer, lithium triflate (LiCF3SO3) and sodium triflate (NaCF3SO3) as inorganic salts were prepared by the solution cast technique. The pure PAN film was prepared as a reference. The ionic conductivity for the films is characterized using impedance spectroscopy. The room temperature conductivity for the PAN+24 wt.%EC film, PAN+26 wt.%LiCF3SO3 film, the PAN+24 wt.%NaCF3SO3 film is 3.43×10-11 S cm-1, 3.04×10-4 S cm-1, and 7.13×10-4 S cm-1, respectively. On addition of plasticizer, the room temperature of PAN+LiCF3SO3 and PAN+NaCF3SO3 films increases by one order of magnitude. The conductivity-temperature and conductivity-pressure dependence studies are then performed on the highest conducting film from the unplasticized and plasticized systems in the temperature and pressure range between 303 K and 373 K and 0.01 MPa and 0.09 MPa, respectively. The conductivity-temperature studies indicate the activation energy, Ea for all system decrease with the increase of the conductivity. The activation volume, ΔV* for each system can be determined from the plot of ln σ versus pressure. It can be observed that the ΔV* is decreased as the conductivity increased. This result can be explained in term of free volume.

  10. An ionic liquid process for mercury removal from natural gas.

    PubMed

    Abai, Mahpuzah; Atkins, Martin P; Hassan, Amiruddin; Holbrey, John D; Kuah, Yongcheun; Nockemann, Peter; Oliferenko, Alexander A; Plechkova, Natalia V; Rafeen, Syamzari; Rahman, Adam A; Ramli, Rafin; Shariff, Shahidah M; Seddon, Kenneth R; Srinivasan, Geetha; Zou, Yiran

    2015-05-14

    Efficient scrubbing of mercury vapour from natural gas streams has been demonstrated both in the laboratory and on an industrial scale, using chlorocuprate(II) ionic liquids impregnated on high surface area porous solid supports, resulting in the effective removal of mercury vapour from natural gas streams. This material has been commercialised for use within the petroleum gas production industry, and has currently been running continuously for three years on a natural gas plant in Malaysia. Here we report on the chemistry underlying this process, and demonstrate the transfer of this technology from gram to ton scale.

  11. Study of a Li-air battery having an electrolyte solution formed by a mixture of an ether-based aprotic solvent and an ionic liquid

    NASA Astrophysics Data System (ADS)

    Cecchetto, Laura; Salomon, Mark; Scrosati, Bruno; Croce, Fausto

    2012-09-01

    Recent studies have clearly demonstrated that cyclic and linear carbonates are unstable when used in rechargeable Li-air batteries employing aprotic solvents mostly due to the cathodic formation of superoxide during the oxygen reduction reaction. In particular, it has been ascertained that nucleophilic attack by superoxide anion radical, O2-rad , at O-alkyl carbon is a common mechanism of decomposition of organic carbonates. Moreover, theoretical calculations showed that ether chemical functionalities are stable against nucleophilic substitution induced by superoxide. Aim of this study is to report on a new electrolyte solution for Li-air battery formed by a mixture of an ether-based aprotic solvent with an ionic liquid (IL). The IL-based electrolyte was obtained by mixing the pure ionic liquid N-methyl-(n-butyl) pyrrolidinium bis(trifluoromethane sulfonyl) imide (here denoted as PYR14TFSI) to a 0.91 M solution of lithium triflate (LiCF3SO3) in tetra ethylene glycol dimethyl etcher (TEGDME). We observed that the presence of IL beneficially affects the kinetics and the reversibility of the oxygen reactions involved at the cathode. The most significant result being a lower overvoltage for the charge reaction, compared to a Li/air cell containing the same electrolyte solution without IL.

  12. Engineering the Electrochemical Capacitive Properties of Microsupercapacitors Based on Graphene Quantum Dots/MnO2 Using Ionic Liquid Gel Electrolytes.

    PubMed

    Shen, Baoshou; Lang, Junwei; Guo, Ruisheng; Zhang, Xu; Yan, Xingbin

    2015-11-18

    All-solid-state microsupercapacitors (MSCs) have been receiving intense interest due to their potential as micro/nanoscale energy storage devices, but their low energy density has limited practical applications. It has been reported that gel electrolytes based on ionic liquids (ionogels) with large potential windows can be used as solid electrolytes to enhance the energy density of MSCs, but a systematic study on how to select and evaluate such ionogels for MSCs is rare. In this study, we construct a series of all-solid-state asymmetric MSCs on the interdigital finger electrodes, using graphene quantum dots (GQDs) as the negative electrode, MnO2 nanosheets as the positive electrode, and different ionogels as the solid electrolytes. Among them, the MSC using 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIM][NTF2]) with 4 wt % fumed SiO2 ionogel exhibited the best electrochemical performance, having excellent rate capability with the scan rate up to 2000 V s(-1), ultrafast frequency response (τ0 = 206.9 μs) and high energy density. The outstanding performance of this device mainly results from fast ion diffusion, high ion conductivity of the ionogel, and ionic liquid-matrix interactions. The results presented here provide guidance for picking out appropriate ionogels for use in high-performance all-solid-state MSCs to meet the growing requirement of micronanoscale energy storage devices. Additionally, the ultrafast frequency response of our MSCs suggests potential applications in ac line-filters.

  13. Elastic strain at interfaces and its influence on ionic conductivity in nanoscaled solid electrolyte thin films--theoretical considerations and experimental studies.

    PubMed

    Schichtel, N; Korte, C; Hesse, D; Janek, J

    2009-05-07

    Ionic transport in solids parallel to grain or phase boundaries is usually strongly enhanced compared to the bulk. Transport perpendicular to an interface (across an interface) is often much slower. Therefore in modern micro- and nanoscaled devices, a severe influence on the ionic/atomic transport properties can be expected due to the high density of interfaces.Transport processes in boundaries of ionic materials are still not understood on an atomic scale. In most of the studies on ionic materials the interfacial transport properties are explained by the influence of space charge regions. Here we discuss the influence of interfacial strain at semicoherent or coherent heterophase boundaries on ionic transport along these interfaces in ionic materials. A qualitative model is introduced for (untilted and untwisted) hetero phase boundaries. For experimental verification, the interfacial oxygen ionic conductivity of different multilayer systems consisting of cubic ZrO(2) stabilised by aliovalent dopands (YSZ, CSZ) and an insulating oxide is investigated as a function of structural mismatch. Recent results on extremely fast ionic conduction in YSZ/SrTiO(3) thin film systems ("colossal ionic concuctivity at interfaces") is discussed from the viewpoint of strain effects.

  14. Enhanced ionic conductivity with Li7O2Br3 phase in Li3OBr anti-perovskite solid electrolyte

    SciTech Connect

    Zhu, Jinlong; Li, Shuai; Zhang, Yi; Howard, John W.; Lu, Xujie; Li, Yutao; Wang, Yonggang; Kumar, Ravhi S.; Wang, Liping; Zhao, Yusheng

    2016-09-07

    Cubic anti-perovskites with general formula Li3OX (X = Cl, Br, I) were recently reported as superionic conductors with the potential for use as solid electrolytes in all-solid-state lithium ion batteries. These electrolytes are nonflammable, low-cost, and suitable for thermoplastic processing. However, the primary obstacle of its practical implementation is the relatively low ionic conductivity at room temperature. In this work, we synthesized a composite material consisting of two anti-perovskite phases, namely, cubic Li3OBr and layered Li7O2Br3, by solid state reaction routes. The results indicate that with the phase fraction of Li7O2Br3 increasing to 44 wt. %, the ionic conductivity increased by more than one order of magnitude compared with pure phase Li3OBr. Formation energy calculations revealed the meta-stable nature of Li7O2Br3, which supports the great difficulty in producing phase-pure Li7O2Br3 at ambient pressure. Here, methods of obtaining phase-pure Li7O2Br3 will continue to be explored, including both high pressure and metathesis techniques.

  15. Glass transition and relaxation processes of nanocomposite polymer electrolytes.

    PubMed

    Money, Benson K; Hariharan, K; Swenson, Jan

    2012-07-05

    This study focus on the effect of δ-Al(2)O(3) nanofillers on the dc-conductivity, glass transition, and dielectric relaxations in the polymer electrolyte (PEO)(4):LiClO(4). The results show that there are three dielectric relaxation processes, α, β, and γ, in the systems, although the structural α-relaxation is hidden in the strong conductivity contribution and could therefore not be directly observed. However, by comparing an enhanced dc-conductivity, by approximately 2 orders of magnitude with 4 wt % δ-Al(2)O(3) added, with a decrease in calorimetric glass transition temperature, we are able to conclude that the dc-conductivity is directly coupled to the hidden α-relaxation, even in the presence of nanofillers (at least in the case of δ-Al(2)O(3) nanofillers at concentrations up to 4 wt %). This filler induced speeding up of the segmental polymer dynamics, i.e., the α-relaxation, can be explained by the nonattractive nature of the polymer-filler interactions, which enhance the "free volume" and mobility of polymer segments in the vicinity of filler surfaces.

  16. Apparatus and process for the electrolytic reduction of uranium and plutonium oxides

    DOEpatents

    Poa, David S.; Burris, Leslie; Steunenberg, Robert K.; Tomczuk, Zygmunt

    1991-01-01

    An apparatus and process for reducing uranium and/or plutonium oxides to produce a solid, high-purity metal. The apparatus is an electrolyte cell consisting of a first container, and a smaller second container within the first container. An electrolyte fills both containers, the level of the electrolyte in the first container being above the top of the second container so that the electrolyte can be circulated between the containers. The anode is positioned in the first container while the cathode is located in the second container. Means are provided for passing an inert gas into the electrolyte near the lower end of the anode to sparge the electrolyte and to remove gases which form on the anode during the reduction operation. Means are also provided for mixing and stirring the electrolyte in the first container to solubilize the metal oxide in the electrolyte and to transport the electrolyte containing dissolved oxide into contact with the cathode in the second container. The cell is operated at a temperature below the melting temperature of the metal product so that the metal forms as a solid on the cathode.

  17. Investigation of Structure and Transport in Li-Doped Ionic Liquid Electrolytes: [pyr14][TFSI], [pyr13][FSI], [EMIM][BF4

    NASA Technical Reports Server (NTRS)

    Haskins, Justin B.; Bennett, William R.; Wu, James J.; Hernandez, Dionne M.; Borodin, Oleg; Monk, Joshua D.; Bauschlicher, Charles W., Jr.; Lawson, John W.

    2014-01-01

    Ionic liquid electrolytes have been proposed as a means of improving the safety and cycling behavior of advanced lithium batteries; however, the properties of these electrolytes under high lithium doping are poorly understood. Here, we employ both polarizable molecular dynamics simulation and experiment to investigate the structure, thermodynamics and transport of three potential electrolytes, N-methyl-N-butylpyrrolidinium bis(trifluoromethylsufonyl)imide ([pyr14][TFSI]), N- methyl-N-propylpyrrolidinium bis(fluorosufonyl)imide ([pyr13][FSI]), and 1-ethyl-3-- methylimidazolium boron tetrafluoride ([EMIM][BF4]), as a function of Li (-) salt concentration and temperature. Structurally, Li(+) is shown to be solvated by three anion neighbors in [pyr14][TFSI] and four anion neighbors in both [pyr13][FSI] and [EMIM][BF4], and at all levels of xLi we find the presence of lithium aggregates. Furthermore, the computed density, diffusion, viscosity, and ionic conductivity show excellent agreement with experimental data. While the diffusion and viscosity exhibit a systematic decrease and increase, respectively, with increasing xLi, the contribution of Li(+) to ionic conductivity increases until reaching a saturation doping level of xLi 0.10. Comparatively, the Li(+) conductivity of [pyr14][TFSI] is an order of magnitude lower than that of the other liquids, which range between 0.1-0.3 mScm. The differences in Li(+) transport are reflected in the residence times of Li(+) with the anions, which are revealed to be much larger for [pyr14][TFSI] (up to 100 ns at the highest doping levels) than in either [EMIM][BF4] or [pyr13][FSI]. Finally, we comment on the relative kinetics of Li(+) transport in each liquid and we present strong evidence for transport through anion exchange (hopping) as opposed to the net motion of Li(+) with its solvation shell (vehicular).

  18. Investigation of Structure and Transport in Li-Doped Ionic Liquid Electrolytes: [pyr14][TFSI], [pyr13][FSI] and [EMIM][BF4

    NASA Technical Reports Server (NTRS)

    Haskins, Justin B.; Bennett, William R.; Hernandez-Lugo, Dione M.; Wu, James; Borodin, Oleg; Monk, Joshua D.; Bauschlicher, Charles W.; Lawson, John W.

    2014-01-01

    Ionic liquid electrolytes have been proposed as a means of improving the safety and cycling behavior of advanced lithium batteries; however, the properties of these electrolytes under high lithium doping are poorly understood. Here, we employ both polarizable molecular dynamics simulation and experiment to investigate the structure, thermodynamics and transport of three potential electrolytes, N-methyl-Nbutylpyrrolidinium bis(trifluoromethylsufonyl)imide ([pyr14][TFSI]), N- methyl-Npropylpyrrolidinium bis(fluorosufonyl)imide ([pyr13][FSI]), and 1-ethyl-3-- methylimidazolium boron tetrafluoride ([EMIM][BF4]), as a function of Li-salt concentration and temperature. Structurally, Li(+) is shown to be solvated by three anion neighbors in [pyr14][TFSI] and four anion neighbors in both [pyr13][FSI] and [EMIM][BF4], and at all levels of x(sub Li) we find the presence of lithium aggregates. Furthermore, the computed density, diffusion, viscosity, and ionic conductivity show excellent agreement with experimental data. While the diffusion and viscosity exhibit a systematic decrease and increase, respectively, with increasing x(sub Li), the contribution of Li(+) to ionic conductivity increases until reaching a saturation doping level of x(sub Li) is approximately 0.10. Comparatively, the Li(+) conductivity of [pyr14][TFSI] is an order of magnitude lower than that of the other liquids, which range between 0.1 - 0.3 mS/cm. The differences in Li(+) transport are reflected in the residence times of Li(+) with the anions, which are revealed to be much larger for [pyr14][TFSI] (up to 100 ns at the highest doping levels) than in either [EMIM][BF4] or [pyr13][FSI]. Finally, we comment on the relative kinetics of Li(+) transport in each liquid and we present strong evidence for transport through anion exchange (hopping) as opposed to the net motion of Li(+) with its solvation shell (vehicular).

  19. Physical properties of high Li-ion content N-propyl-N-methylpyrrolidinium bis(fluorosulfonyl)imide based ionic liquid electrolytes.

    PubMed

    Yoon, Hyungook; Best, Adam S; Forsyth, Maria; MacFarlane, Douglas R; Howlett, Patrick C

    2015-02-14

    Electrolytes based on bis(fluorosulfonyl)imide (FSI) with a range of LiFSI salt concentrations were characterized using physical property measurements, as well as NMR, FT-IR and Raman spectroscopy. Different from the behavior at lower concentrations, the FSI electrolyte containing 1 : 1 salt to IL mole ratio showed less deviation from the KCl line in the Walden plot, suggesting greater ionic dissociation. Diffusion measurements show higher mobility of lithium ions compared to the other ions, which suggests that the partial conductivity of Li(+) is higher at this higher composition. Changes in the FT-IR and Raman peaks indicate that the cis-FSI conformation is preferred with increasing Li salt concentration.

  20. A numerical investigation of the diesel particle filter regeneration process under temperature pulse conditions

    NASA Astrophysics Data System (ADS)

    Meng, Zhongwei; Zhang, Jing; Chen, Chao; Yan, Yan

    2016-10-01

    A one-dimensional transient diesel particle filter (DPF) model is applied to study DPF regeneration performance. Numerical simulations are performed to predict the effects of various factors influencing regeneration performance under temperature pulse conditions, and the regeneration performances of three typical DPFs are compared and analyzed. Numerical results indicate that the thermal conductivity characteristics of DPF configurations can greatly affect soot oxidation, which in turn influences the regeneration process. The transition points of the regeneration flow rate indicate a balance between its promotion of the regeneration process and retardation owing to cooling effects. The sensitive ranges of soot loading, oxygen concentration, and inlet temperature are observed to provide a reference for controlling DPF regeneration. The multi-step exhaust condition is employed to control DPF regeneration. It was found that a transient increase in the flow rate is more effective at reducing the peak temperature and peak temperature gradient than a transient decrease of oxygen concentration.

  1. Effects of compatibility of polymer binders with solvate ionic liquid electrolytes on discharge and charge reactions of lithium-sulfur batteries

    NASA Astrophysics Data System (ADS)

    Nakazawa, Toshitada; Ikoma, Ai; Kido, Ryosuke; Ueno, Kazuhide; Dokko, Kaoru; Watanabe, Masayoshi

    2016-03-01

    Electrochemical reactions in Li-S cells with a solvate ionic liquid (SIL) electrolyte composed of tetraglyme (G4) and Li[TFSA] (TFSA: bis(trifluoromethanesulfonyl)amide) are studied. The sulfur cathode (S cathode) comprises sulfur, carbon powder, and a polymer binder. Poly(ethylene oxide) (PEO) and poly(vinyl alcohol) (PVA-x) with different degrees of saponification (x%) are used as binders to prepare the composite cathodes. For the Li-S cell containing PEO binder, lithium polysulfides (Li2Sm, 2 ≤ m ≤ 8), reaction intermediates of the S cathode, dissolve into the electrolyte, and Li2Sm acts as a redox shuttle in the Li-S cell. In contrast, in the Li-S cell with PVA-x binder, the dissolution of Li2Sm is suppressed, leading to high columbic efficiencies during charge-discharge cycles. The compatibility of the PVA-x binder with the SIL electrolyte changes depending on the degree of saponification. Decreasing the degree of saponification leads to increased electrolyte uptake by the PVA-x binder, increasing the charge and discharge capacities of Li-S cell. The rate capability of Li-S cell is also enhanced by the partial swelling of the PVA-x binder. The enhanced performance of Li-S cell containing PVA-x is attributed to the lowering of resistance of Li+ ion transport in the composite cathode.

  2. Inkjet printing of nanoporous gold electrode arrays on cellulose membranes for high-sensitive paper-like electrochemical oxygen sensors using ionic liquid electrolytes.

    PubMed

    Hu, Chengguo; Bai, Xiaoyun; Wang, Yingkai; Jin, Wei; Zhang, Xuan; Hu, Shengshui

    2012-04-17

    A simple approach to the mass production of nanoporous gold electrode arrays on cellulose membranes for electrochemical sensing of oxygen using ionic liquid (IL) electrolytes was established. The approach, combining the inkjet printing of gold nanoparticle (GNP) patterns with the self-catalytic growth of these patterns into conducting layers, can fabricate hundreds of self-designed gold arrays on cellulose membranes within several hours using an inexpensive inkjet printer. The resulting paper-based gold electrode arrays (PGEAs) had several unique properties as thin-film sensor platforms, including good conductivity, excellent flexibility, high integration, and low cost. The porous nature of PGEAs also allowed the addition of electrolytes from the back cellulose membrane side and controllably produced large three-phase electrolyte/electrode/gas interfaces at the front electrode side. A novel paper-based solid-state electrochemical oxygen (O(2)) sensor was therefore developed using an IL electrolyte, 1-butyl-3-methylimidazolium hexafluorophosphate (BMIMPF(6)). The sensor looked like a piece of paper but possessed high sensitivity for O(2) in a linear range from 0.054 to 0.177 v/v %, along with a low detection limit of 0.0075% and a short response time of less than 10 s, foreseeing its promising applications in developing cost-effective and environment-friendly paper-based electrochemical gas sensors.

  3. A higher performance dye-sensitized solar cell based on the modified PMII/EMIMBF4 binary room temperature ionic liquid electrolyte

    NASA Astrophysics Data System (ADS)

    Wang, Wu-yang; Cao, Da-peng; Wang, Chao; Zhang, Xiang-yu; Mi, Bao-xiu; Gao, Zhi-qiang; Liang, Zhong-cheng

    2016-07-01

    Additives and iodine (I2) are used to modify the binary room temperature ionic liquid (RTIL) electrolyte to enhance the photovoltaic performance of dye-sensitized solar cells (DSSCs). The short-circuit current density ( J SC) of 17.89 mA/cm2, open circuit voltage ( V OC) of 0.71 V and fill factor ( FF) of 0.50 are achieved in the optimal device. An average photoelectric conversion efficiency ( PCE) of 6.35% is achieved by optimization, which is over two times larger than that of the parent device before optimization (2.06%), while the maximum PCE can reach up to 6.63%.

  4. Study of reversible electrode reaction and mixed ionic and electronic conduction of lithium phosphate electrolyte for an electrochemical CO2 gas sensor

    NASA Astrophysics Data System (ADS)

    Lee, Chong-Hoon

    An electrochemical CO2 gas sensor with lithium ion conductor was developed and characterized in order to examine the potential for real-life applications and understand its sensing mechanism. Li2CO3 and Li2TiO3 + TiO2 mixture were used as a sensing and a reference auxiliary phase, respectively. This electrochemical cell with a solid state Li3PO4 electrolyte has shown good selectivity, sensitivity and linear response in laboratory and automobile exhaust tests. However, the sensor response to CO2 gas showed a systematic deviation from the Nernst equation. Measured EMF did not agree with that calculated from the Nernst equation, even though it followed logarithmic behavior. Moreover, high sensitivity was observed for high CO2 concentrations (5˜50%), compared to that for concentrations (500˜5000 ppm). Two possible reasons for this deviation are: (1) reversibility of electrode reaction and (2) mixed ionic and electronic conduction of the electrolyte. Unless electrode reaction is fast enough, electrode polarization can easily induce overpotential. Pure ionic conduction of electrolyte is also necessary to avoid EMF loss during open circuit potential measurement. EIS (Electrochemical Impedance Spectroscopy) was used to study electrode kinetics. We found that Li2TiO3 + TiO2 mixture reference electrode reaction is sluggish showing large electrode impedance. This impedance, however, was not affected by gas concentration change. On the other hand, that at the Li2CO3 sensing electrode is relatively small and it increased with decreased CO2 and O 2 concentration. It was also observed that these electrode impedances induced the overpotential when the current flowed through the sensor. This electrode overpotential problem was minimized by mixing gold powder or porous sputtered gold electrode increasing effective reaction sites of the electrode. New electrode design improved the sensor EMF closer to the Nernstian values, however, the discrepancy still remained. Moreover, at

  5. Zn2+ and Sr2+ Adsorption at the TiO2 (110)-Electrolyte Interface: Influence of Ionic Strength, Coverage, and Anions

    SciTech Connect

    Zhang,Z.; Fenter, P.; Cheng, L.; Sturchio, N.; Bedzyk, M.; Machesky, M.; Anovitz, L.; Wesolowski, D.

    2006-01-01

    The X-ray standing wave technique was used to probe the sensitivity of Zn{sup 2+} and Sr{sup 2+} ion adsorption to changes in both the adsorbed ion coverage and the background electrolyte species and concentrations at the rutile ({alpha}-TiO{sub 2}) (110)-aqueous interface. Measurements were made with various background electrolytes (NaCl, NaTr, RbCl, NaBr) at concentrations as high as 1 m. The results demonstrate that Zn{sub 2+} and Sr{sub 2+} reside primarily in the condensed layer and that the ion heights above the Ti-O surface plane are insensitive to ionic strength and the choice of background electrolyte (with <0.1 Angstroms changes over the full compositional range). The lack of any specific anion coadsorption upon probing with Br{sup -}, coupled with the insensitivity of Zn{sup 2+} and Sr{sup 2+} cation heights to changes in the background electrolyte, implies that anions do not play a significant role in the adsorption of these divalent metal ions to the rutile (110) surface. Absolute ion coverage measurements for Zn{sup 2+} and Sr{sup 2+} show a maximum Stern-layer coverage of {approx}0.5 monolayer, with no significant variation in height as a function of Stern-layer coverage. These observations are discussed in the context of Gouy-Chapman-Stern models of the electrical double layer developed from macroscopic sorption and pH-titration studies of rutile powder suspensions. Direct comparison between these experimental observations and the MUltiSIte Complexation (MUSIC) model predictions of cation surface coverage as a function of ionic strength revealed good agreement between measured and predicted surface coverages with no adjustable parameters.

  6. The potential of incorporation of binary salts and ionic liquid in P(VP-co-VAc) gel polymer electrolyte in electrochemical and photovoltaic performances

    PubMed Central

    Ming, Ng Hon; Ramesh, S.; Ramesh, K.

    2016-01-01

    In this study, dye-sensitized solar cells (DSSCs) has been assembled with poly(1-vinylpyrrolidone-co-vinyl acetate) (P(VP-co-VAc)) gel polymer electrolytes (GPEs) which have been incorporated with binary salt and an ionic liquid. The potential of this combination was studied and reported. The binary salt system GPEs was having ionic conductivity and power conversion efficiency (PCE) that could reach up to 1.90 × 10−3 S cm−1 and 5.53%, respectively. Interestingly, upon the addition of the ionic liquid, MPII into the binary salt system the ionic conductivity and PCE had risen steadily up to 4.09 × 10−3 S cm−1 and 5.94%, respectively. In order to know more about this phenomenon, the electrochemical impedance studies (EIS) of the GPE samples have been done and reported. Fourier transform infrared studies (FTIR) and thermogravimetric analysis (TGA) have also been studied to understand more on the structural and thermal properties of the GPEs. The Nyquist plot and Bodes plot studies have been done in order to understand the electrochemical properties of the GPE based DSSCs and Tafel polarization studies were done to determine the electrocatalytic activity of the GPE samples. PMID:27273020

  7. The potential of incorporation of binary salts and ionic liquid in P(VP-co-VAc) gel polymer electrolyte in electrochemical and photovoltaic performances

    NASA Astrophysics Data System (ADS)

    Ming, Ng Hon; Ramesh, S.; Ramesh, K.

    2016-06-01

    In this study, dye-sensitized solar cells (DSSCs) has been assembled with poly(1-vinylpyrrolidone-co-vinyl acetate) (P(VP-co-VAc)) gel polymer electrolytes (GPEs) which have been incorporated with binary salt and an ionic liquid. The potential of this combination was studied and reported. The binary salt system GPEs was having ionic conductivity and power conversion efficiency (PCE) that could reach up to 1.90 × 10‑3 S cm‑1 and 5.53%, respectively. Interestingly, upon the addition of the ionic liquid, MPII into the binary salt system the ionic conductivity and PCE had risen steadily up to 4.09 × 10‑3 S cm‑1 and 5.94%, respectively. In order to know more about this phenomenon, the electrochemical impedance studies (EIS) of the GPE samples have been done and reported. Fourier transform infrared studies (FTIR) and thermogravimetric analysis (TGA) have also been studied to understand more on the structural and thermal properties of the GPEs. The Nyquist plot and Bodes plot studies have been done in order to understand the electrochemical properties of the GPE based DSSCs and Tafel polarization studies were done to determine the electrocatalytic activity of the GPE samples.

  8. The potential of incorporation of binary salts and ionic liquid in P(VP-co-VAc) gel polymer electrolyte in electrochemical and photovoltaic performances.

    PubMed

    Ming, Ng Hon; Ramesh, S; Ramesh, K

    2016-06-08

    In this study, dye-sensitized solar cells (DSSCs) has been assembled with poly(1-vinylpyrrolidone-co-vinyl acetate) (P(VP-co-VAc)) gel polymer electrolytes (GPEs) which have been incorporated with binary salt and an ionic liquid. The potential of this combination was studied and reported. The binary salt system GPEs was having ionic conductivity and power conversion efficiency (PCE) that could reach up to 1.90 × 10(-3) S cm(-1) and 5.53%, respectively. Interestingly, upon the addition of the ionic liquid, MPII into the binary salt system the ionic conductivity and PCE had risen steadily up to 4.09 × 10(-3) S cm(-1) and 5.94%, respectively. In order to know more about this phenomenon, the electrochemical impedance studies (EIS) of the GPE samples have been done and reported. Fourier transform infrared studies (FTIR) and thermogravimetric analysis (TGA) have also been studied to understand more on the structural and thermal properties of the GPEs. The Nyquist plot and Bodes plot studies have been done in order to understand the electrochemical properties of the GPE based DSSCs and Tafel polarization studies were done to determine the electrocatalytic activity of the GPE samples.

  9. Using Ionic Liquids in Selective Hydrocarbon Conversion Processes

    SciTech Connect

    Tang, Yongchun; Periana, Roy; Chen, Weiqun; van Duin, Adri; Nielsen, Robert; Shuler, Patrick; Ma, Qisheng; Blanco, Mario; Li, Zaiwei; Oxgaard, Jonas; Cheng, Jihong; Cheung, Sam; Pudar, Sanja

    2009-09-28

    This is the Final Report of the five-year project Using Ionic Liquids in Selective Hydrocarbon Conversion Processes (DE-FC36-04GO14276, July 1, 2004- June 30, 2009), in which we present our major accomplishments with detailed descriptions of our experimental and theoretical efforts. Upon the successful conduction of this project, we have followed our proposed breakdown work structure completing most of the technical tasks. Finally, we have developed and demonstrated several optimized homogenously catalytic methane conversion systems involving applications of novel ionic liquids, which present much more superior performance than the Catalytica system (the best-to-date system) in terms of three times higher reaction rates and longer catalysts lifetime and much stronger resistance to water deactivation. We have developed in-depth mechanistic understandings on the complicated chemistry involved in homogenously catalytic methane oxidation as well as developed the unique yet effective experimental protocols (reactors, analytical tools and screening methodologies) for achieving a highly efficient yet economically feasible and environmentally friendly catalytic methane conversion system. The most important findings have been published, patented as well as reported to DOE in this Final Report and our 20 Quarterly Reports.

  10. A counter-charge layer in generalized solvents framework for electrical double layers in neat and hybrid ionic liquid electrolytes

    SciTech Connect

    Huang, Jingsong; Feng, Guang; Sumpter, Bobby G; Qiao, Rui; Meunier, Vincent

    2011-01-01

    Room-temperature ionic liquids (RTILs) have received significant attention as electrolytes due to a number of attractive properties such as their wide electrochemical windows. Since electrical double layers (EDLs) are the cornerstone for the applications of RTILs in electrochemical systems such as supercapacitors, it is important to develop an understanding of the structure capacitance relationships for these systems. Here we present a theoretical framework termed counter-charge layer in generalized solvents (CGS) for describing the structure and capacitance of the EDLs in neat RTILs and in RTILs mixed with different mass fractions of organic solvents. Within this framework, an EDL is made up of a counter-charge layer exactly balancing the electrode charge, and of polarized generalized solvents (in the form of layers of ion pairs, each of which has a zero net charge but has a dipole moment the ion pairs thus can be considered as a generalized solvent) consisting of all RTILs inside the system except the counter-ions in the counter-charge layer, together with solvent molecules if present. Several key features of the EDLs that originate from the strong ion ion correlation in RTILs, e.g., overscreening of electrode charge and alternating layering of counter-ions and co-ions, are explicitly incorporated into this framework. We show that the dielectric screening in EDLs is governed predominately by the polarization of generalized solvents (or ion pairs) in the EDL, and the capacitance of an EDL can be related to its microstructure with few a priori assumptions or simplifications. We use this framework to understand two interesting phenomena observed in molecular dynamics simulations of EDLs in a neat IL of 1-butyl-3- methylimidazolium tetrafluoroborate ([BMIM][BF4]) and in a mixture of [BMIM][BF4] and acetonitrile (ACN): (1) the capacitance of the EDLs in the [BMIM][BF4]/ACN mixture increases only slightly when the mass fraction of ACN in the mixture increases from zero

  11. Study on a regeneration process of LiCl-KCl eutectic based waste salt generated from the pyrochemical process

    SciTech Connect

    Eun, H.C.; Cho, Y.Z.; Choi, J.H.; Kim, J.H.; Lee, T.K.; Park, H.S.; Kim, I.T.; Park, G.I.

    2013-07-01

    A regeneration process of LiCl-KCl eutectic waste salt generated from the pyrochemical process of spent nuclear fuel has been studied. This regeneration process is composed of a chemical conversion process and a vacuum distillation process. Through the regeneration process, a high efficiency of renewable salt recovery can be obtained from the waste salt and rare earth nuclides in the waste salt can be separated as oxide or phosphate forms. Thus, the regeneration process can contribute greatly to a reduction of the waste volume and a creation of durable final waste forms. (authors)

  12. In situ visualization of the electrolyte solvent filling process by neutron radiography

    NASA Astrophysics Data System (ADS)

    Knoche, Thomas; Zinth, Veronika; Schulz, Michael; Schnell, Joscha; Gilles, Ralph; Reinhart, Gunther

    2016-11-01

    In the manufacturing of Li-ion battery cells, filling with electrolyte liquid is a crucial step in terms of product quality and cost. To gain insight into the process phenomena, a non-destructive imaging method is presented. It is shown that the spreading of electrolyte liquid within the cell during filling and wetting can be visualized by neutron radiography. The experiment allows for the first time to visualize the soaking behaviour of electrolyte liquid in battery cells. The influence of the process parameters on the wetting behaviour is studied and flow paths of the liquid are identified. The electrolyte intake into the cell stack is discussed with two different analytical approaches. Based on the experimental data, the production process can be optimized, leading to stable cell performance and cost reduction due to faster processes and lower scrap rates.

  13. Compatibility of poly(bisAEA4)-LiTFSI-MPPipTFSI ionic liquid gel polymer electrolyte with Li4Ti5O12 lithium ion battery anode

    NASA Astrophysics Data System (ADS)

    Stepniak, Izabela

    2014-02-01

    This paper presents the use of Li4Ti5O12 (LTO) as anode with ionic liquid gel polymer electrolyte (IL-GPE) for application in lithium ion batteries. IL-GPE was obtained by in situ photopolymerization method of a mixture of ethoxylated bisphenol A diacrylate (bis(AEA4) and 0.4 M solution of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) in N-methyl-N-propylpiperidinium bis(trifluoromethanesulfonyl)imide (MPPipTFSI). The surface morphology of the IL-GPE was studied using scanning electron microscopy (SEM). Stable, porous and flexible gel polymer electrolyte characterized high ionic conductivity (0.64 mS cm-1 at 25 °C) and a wide electrochemical stability window (ESW) (4.8 V). The performances of LTO/IL-GPE/Li cell were tested by using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and galvanostatic charge/discharge. Good charge/discharge capacities and low capacity loss at medium C rates preliminary cycling was obtained.

  14. Solid polymer electrolyte compositions

    DOEpatents

    Garbe, James E.; Atanasoski, Radoslav; Hamrock, Steven J.; Le, Dinh Ba

    2001-01-01

    An electrolyte composition is featured that includes a solid, ionically conductive polymer, organically modified oxide particles that include organic groups covalently bonded to the oxide particles, and an alkali metal salt. The electrolyte composition is free of lithiated zeolite. The invention also features cells that incorporate the electrolyte composition.

  15. Understanding the transport processes in polymer electrolyte membrane fuel cells

    NASA Astrophysics Data System (ADS)

    Cheah, May Jean

    Polymer electrolyte membrane (PEM) fuel cells are energy conversion devices suitable for automotive, stationary and portable applications. An engineering challenge that is hindering the widespread use of PEM fuel cells is the water management issue, where either a lack of water (resulting in membrane dehydration) or an excess accumulation of liquid water (resulting in fuel cell flooding) critically reduces the PEM fuel cell performance. The water management issue is addressed by this dissertation through the study of three transport processes occurring in PEM fuel cells. Water transport within the membrane is a combination of water diffusion down the water activity gradient and the dragging of water molecules by protons when there is a proton current, in a phenomenon termed electro-osmotic drag, EOD. The impact of water diffusion and EOD on the water flux across the membrane is reduced due to water transport resistance at the vapor/membrane interface. The redistribution of water inside the membrane by EOD causes an overall increase in the membrane resistance that regulates the current and thus EOD, thereby preventing membrane dehydration. Liquid water transport in the PEM fuel cell flow channel was examined at different gas flow regimes. At low gas Reynolds numbers, drops transitioned into slugs that are subsequently pushed out of the flow channel by the gas flow. The slug volume is dependent on the geometric shape, the surface wettability and the orientation (with respect to gravity) of the flow channel. The differential pressure required for slug motion primarily depends on the interfacial forces acting along the contact lines at the front and the back of the slug. At high gas Reynolds number, water is removed as a film or as drops depending on the flow channel surface wettability. The shape of growing drops at low and high Reynolds number can be described by a simple interfacial energy minimization model. Under flooding conditions, the fuel cell local current

  16. Exploration on effects of 15 nm SiO2 filler on miscibility, thermal stability and ionic conductivity of PMMA/ENR 50 electrolytes

    NASA Astrophysics Data System (ADS)

    Zamri, S. F. M.; Latif, F. A.; Ali, A. M. M.; Ibrahim, R.; Azuan, S. I. H. M.; Kamaluddin, N.; Hadip, F.

    2017-02-01

    The effects of silicon dioxide (SiO2) (15 nm) filler on miscibility, thermal stability and ionic conductivity of polymethyl methacrylate/50% epoxidized narural rubber (PMMA/ENR 50) electrolytes were successfully explored. Samples were prepared by solvent casting method with tetrahydrofuran (THF) as solvent and doped with lithium tetrafluoroborate (LiBF4). Fourier transform infrared spectroscopy (FTIR) confirmed the present of hydrogen bond between PMMA and ENR 50. However, the hydrogen bond was reduced when SiO2 was added. Differential scanning calorimeter (DSC) analysis shows that PMMA/ENR 50 blends exhibit two glass transition temperatures (Tgs) recorded at -35 and 89 °C corresponding to the Tg of ENR 50 rich phase (Tg1) and PMMA rich phase (Tg2), respectively. However, the two Tgs almost merging and reduced when SiO2 was added. Tg1 was found increases as SiO2 weight percent increased. Thermogravimetric analysis (TGA) revealed that thermal degradation temperatures (Tds) of SiO2 filled PMMA/ENR 50 was similar as PMMA/ENR 50. Interestingly, thermal degradation temperatures of the loss of impurities (Td1) and thermal degradation temperatures of PMMA side chain (Td2) were increased when SiO2 was added. Meanwhile thermal degradation temperatures of main PMMA and ENR 50 main chain (Td3) was decreased as SiO2 was added. There was no significant change in Td1, Td2 and Td3 as SiO2 weight percent was varied. Electrochemical impedence spectroscopy (EIS) analysis shows that room temperature ionic conductivity of SiO2 filled PMMA/ENR 50 electrolytes were higher compaed PMMA/ENR 50 electrolyte with two conductivity maxima.

  17. Final Technical Report: SISGR: The Influence of Electrolyte Structure and Electrode Morphology on the Performance of Ionic-Liquid Based Supercapacitors: A Combined Experimental and Simulation Study

    SciTech Connect

    Bedrov, Dmitry

    2013-08-15

    Obtaining fundamental understanding and developing predictive modeling capabilities of electrochemical interfaces can significantly shorten the development cycles of electrical double layer capacitors (EDLCs). A notable improvement in EDLC performance has been achieved due to recent advances in understanding charge storage mechanisms, development of advanced nanostructured electrodes and electrochemically stable electrolytes. The development of new generation of EDLCs is intimately linked to that of nanostructured carbon materials which have large surface area, good adsorption/desorption properties, good electrical conductivity and are relatively inexpensive. To address these scientific challenges the efforts of an interdisciplinary team of modelers and experimentalists were combined to enhance our understanding of molecular level mechanisms controlling the performance of EDLCs comprised of room temperature ionic liquid (RTIL) electrolytes and nanostructured carbon-based electrodes and to utilize these knowledge in the design of a new generation of materials and devices for this energy storage application. Specifically our team efforts included: atomistic molecular dynamics simulations, materials science and electrode/device assembly, and synthesis and characterization of RTIL electrolytes.

  18. Experimental Investigation into the Transmembrane Electrical Potential of the Forward Osmosis Membrane Process in Electrolyte Solutions

    PubMed Central

    Bian, Lixia; Fang, Yanyan; Wang, Xiaolin

    2014-01-01

    The transmembrane electrical potential (TMEP) in a forward osmosis membrane process with a single electrolyte solution as the draw and feed solutions was investigated by experiments. The effects of membrane orientation, the electrolyte species (KCl, NaCl, MgCl2, and CaCl2), concentration and concentration ratio of solutions at both sides of membrane on water flux and TMEP were investigated. The results showed that the TMEPs at different membrane orientation cannot completely coincide, which confirmed the effect of membrane asymmetry. The ion diffusion coefficients significantly affected the TMEP across the membrane, with different patterns for different electrolytes and concentrations. PMID:24957177

  19. Experimental investigation into the transmembrane electrical potential of the forward osmosis membrane process in electrolyte solutions.

    PubMed

    Bian, Lixia; Fang, Yanyan; Wang, Xiaolin

    2014-06-19

    The transmembrane electrical potential (TMEP) in a forward osmosis membrane process with a single electrolyte solution as the draw and feed solutions was investigated by experiments. The effects of membrane orientation, the electrolyte species (KCl, NaCl, MgCl2, and CaCl2), concentration and concentration ratio of solutions at both sides of membrane on water flux and TMEP were investigated. The results showed that the TMEPs at different membrane orientation cannot completely coincide, which confirmed the effect of membrane asymmetry. The ion diffusion coefficients significantly affected the TMEP across the membrane, with different patterns for different electrolytes and concentrations.

  20. Influence of Polar Organic Solvents in an Ionic Liquid Containing Lithium Bis(fluorosulfonyl)amide: Effect on the Cation-Anion Interaction, Lithium Ion Battery Performance, and Solid Electrolyte Interphase.

    PubMed

    Lahiri, Abhishek; Li, Guozhu; Olschewski, Mark; Endres, Frank

    2016-12-14

    Ionic liquid-organic solvent mixtures have recently been investigated as potential battery electrolytes. However, contradictory results with these mixtures have been shown for battery performance. In this manuscript, we studied the influence of the addition of polar organic solvents into the ionic liquid electrolyte 1 M lithium bis(fluorosulfonyl)amide (LiFSI)-1-butyl-1-methylpyrrolidinium bis(fluorosulfonyl)amide ([Py1,4]FSI) and tested it for lithium ion battery applications. From infrared and Raman spectroscopy, clear changes in the lithium solvation and cation-anion interactions in the ionic liquid were observed on addition of organic solvents. From the lithiation/delithiation studies on electrodeposited Ge, the storage capacity for the ionic liquid-highly polar organic solvent (acetonitrile) mixture was found to be the highest at low C-rates (0.425 C) compared to using an ionic liquid alone and ionic liquid-less polar solvent (dimethyl carbonate) mixtures. Furthermore, XPS and AFM were used to evaluate the solid electrolyte interphase (SEI) and to correlate its stability with Li storage capacity.

  1. Solvent extraction of gold using ionic liquid based process

    NASA Astrophysics Data System (ADS)

    Makertihartha, I. G. B. N.; Zunita, Megawati; Rizki, Z.; Dharmawijaya, P. T.

    2017-01-01

    In decades, many research and mineral processing industries are using solvent extraction technology for metal ions separation. Solvent extraction technique has been used for the purification of precious metals such as Au and Pd, and base metals such as Cu, Zn and Cd. This process uses organic compounds as solvent. Organic solvents have some undesired properties i.e. toxic, volatile, excessive used, flammable, difficult to recycle, low reusability, low Au recovery, together with the problems related to the disposal of spent extractants and diluents, even the costs associated with these processes are relatively expensive. Therefore, a lot of research have boosted into the development of safe and environmentally friendly process for Au separation. Ionic liquids (ILs) are the potential alternative for gold extraction because they possess several desirable properties, such as a the ability to expanse temperature process up to 300°C, good solvent properties for a wide range of metal ions, high selectivity, low vapor pressures, stability up to 200°C, easy preparation, environmentally friendly (commonly called as "green solvent"), and relatively low cost. This review paper is focused in investigate of some ILs that have the potentials as solvent in extraction of Au from mineral/metal alloy at various conditions (pH, temperature, and pressure). Performances of ILs extraction of Au are studied in depth, i.e. structural relationship of ILs with capability to separate Au from metal ions aggregate. Optimal extraction conditon in order to gain high percent of Au in mineral processing is also investigated.

  2. Metallization pattern on solid electrolyte or porous support of sodium battery process

    DOEpatents

    Kim, Jin Yong; Li, Guosheng; Lu, Xiaochuan; Sprenkle, Vincent L.; Lemmon, John P.

    2016-05-31

    A new battery configuration and process are detailed. The battery cell includes a solid electrolyte configured with an engineered metallization layer that distributes sodium across the surface of the electrolyte extending the active area of the cathode in contact with the anode during operation. The metallization layer enhances performance, efficiency, and capacity of sodium batteries at intermediate temperatures at or below about 200.degree. C.

  3. The Synthesis and Characterization of Ionic Liquids for Alkali-Metal Batteries and a Novel Electrolyte for Non-Humidified Fuel Cells

    NASA Astrophysics Data System (ADS)

    Tucker, Telpriore G.

    This thesis focused on physicochemical and electrochemical projects directed towards two electrolyte types: 1) class of ionic liquids serving as electrolytes in the catholyte for alkali-metal ion conduction in batteries and 2) gel membrane for proton conduction in fuel cells; where overall aims were encouraged by the U.S. Department of Energy. Large-scale, sodium-ion batteries are seen as global solutions to providing undisrupted electricity from sustainable, but power-fluctuating, energy production in the near future. Foreseen ideal advantages are lower cost without sacrifice of desired high-energy densities relative to present lithium-ion and lead-acid battery systems. Na/NiCl2 (ZEBRA) and Na/S battery chemistries, suffer from high operation temperature (>300ºC) and safety concerns following major fires consequent of fuel mixing after cell-separator rupturing. Initial interest was utilizing low-melting organic ionic liquid, [EMI+][AlCl 4-], with well-known molten salt, NaAlCl4, to create a low-to-moderate operating temperature version of ZEBRA batteries; which have been subject of prior sodium battery research spanning decades. Isothermal conductivities of these electrolytes revealed a fundamental kinetic problem arisen from "alkali cation-trapping effect" yet relived by heat-ramping >140ºC. Battery testing based on [EMI+][FeCl4 -] with NaAlCl4 functioned exceptional (range 150-180ºC) at an impressive energy efficiency >96%. Newly prepared inorganic ionic liquid, [PBr4+][Al2Br7-]:NaAl2Br 7, melted at 94ºC. NaAl2Br7 exhibited super-ionic conductivity 10-1.75 Scm-1 at 62ºC ensued by solid-state rotator phase transition. Also improved thermal stability when tested to 265ºC and less expensive chemical synthesis. [PBr4 +][Al2Br7-] demonstrated remarkable, ionic decoupling in the liquid-state due to incomplete bromide-ion transfer depicted in NMR measurements. Fuel cells are electrochemical devices generating electrical energy reacting hydrogen/oxygen gases

  4. Evolutionary loss of animal regeneration: pattern and process.

    PubMed

    Bely, Alexandra E

    2010-10-01

    The ability to regenerate lost or damaged body parts is widespread among animals and provides obvious potential benefits. It is therefore perplexing that this ability has become greatly restricted or completely lost in many lineages. Despite growing interest in the cellular and molecular basis of regeneration, our understanding of how and why regenerative abilities are lost remains rudimentary. In an effort to develop a framework for studying losses of regeneration, here I outline an approach for rigorously identifying such losses, review broad patterns of regenerative ability across animals, describe some of the clearest examples of regeneration loss, discuss some possible scenarios by which regeneration may be lost, and review recent work in annelids that is providing new insights into loss of regenerative ability.

  5. Membrane contactor assisted extraction/reaction process employing ionic liquids

    DOEpatents

    Lin, Yupo J [Naperville, IL; Snyder, Seth W [Lincolnwood, IL

    2012-02-07

    The present invention relates to a functionalized membrane contactor extraction/reaction system and method for extracting target species from multi-phase solutions utilizing ionic liquids. One preferred embodiment of the invented method and system relates to an extraction/reaction system wherein the ionic liquid extraction solutions act as both extraction solutions and reaction mediums, and allow simultaneous separation/reactions not possible with prior art technology.

  6. Cyclic process for producing methane with catalyst regeneration

    DOEpatents

    Frost, Albert C.; Risch, Alan P.

    1980-01-01

    Carbon monoxide-containing gas streams are passed over a catalyst capable of catalyzing the disproportionation of carbon monoxide so as to deposit a surface layer of active surface carbon on the catalyst essentially without formation of inactive coke thereon. The surface layer is contacted with steam and is thus converted to methane and CO.sub.2, from which a relatively pure methane product may be obtained. For practical commercial operations utilizing the two-step process of the invention of a cyclic basis, nickel, cobalt, ruthenium, thenium and alloys thereof are especially prepared for use in a metal state, with CO disproportionation being carried out at temperatures up to about 350.degree. C. and with the conversion of active surface carbon to methane being carried out by reaction with steam. The catalyst is employed in such cyclic operations without the necessity for employing a regeneration step as part of each processing cycle. Inactive carbon or coke that tends to form on the catalyst over the course of continuous operations utilizing such cyclic process is effectively and advantageously removed, on a periodic basis, in place of conventional burn off with an inert stream containing a low concentration of oxygen.

  7. Solidified inorganic-organic hybrid electrolyte for all solid state flexible lithium battery

    NASA Astrophysics Data System (ADS)

    Baek, Seung-Wook; Honma, Itaru; Kim, Jedeok; Rangappa, Dinesh

    2017-03-01

    Solidified lithium conducting hybrid electrolyte is designed and processed to realize the large scale and flexible solid state Li battery satisfying energy capability and safety issue. This paper presents a solidified inorganic-organic hybrid electrolyte to obtain commercially-acceptable ionic conductivity and a stable electrochemical window to prevent electrolyte decomposition in Li ion batteries. Li3PO4 coated with solidified [Li][EMI][TFSI] ionic liquid is developed as hybrid electrolyte material. The material has high electrochemical stability on a high-voltage cathode and metallic anode, and the solid electrolyte has high ionic conductivity. This Li3PO4-[Li][EMI][TFSI] hybrid electrolyte has the advantages of long-term operation, safety and flexibility, so it may be suitable for use in high-voltage cathodes and Li anode.

  8. 12-crown-4 ether-assisted enhancement of ionic conductivity and interfacial kinetics in polyethylene oxide electrolytes

    NASA Technical Reports Server (NTRS)

    Nagasubramanian, G.; Di Stefano, S.

    1990-01-01

    The electrical and electrochemical properties of thin films of polyethylene oxide electrolytes with and without 12-crown-4 ether (12Cr4) are studied as a function of temperature and in the frequency regime from 100 kHz to 0.1 Hz. These measurements were made on electrolytes containing LiCF3SO3, LiBF4, or LiClO4 salts. At a given temperature, the bulk conductivity for a particular salt depends on the 12Cr4 concentration, reaching a maximum for a ratio of 12Cr4 to Li of 0.003.

  9. Gel polymer electrolytes for batteries

    DOEpatents

    Balsara, Nitash Pervez; Eitouni, Hany Basam; Gur, Ilan; Singh, Mohit; Hudson, William

    2014-11-18

    Nanostructured gel polymer electrolytes that have both high ionic conductivity and high mechanical strength are disclosed. The electrolytes have at least two domains--one domain contains an ionically-conductive gel polymer and the other domain contains a rigid polymer that provides structure for the electrolyte. The domains are formed by block copolymers. The first block provides a polymer matrix that may or may not be conductive on by itself, but that can soak up a liquid electrolyte, thereby making a gel. An exemplary nanostructured gel polymer electrolyte has an ionic conductivity of at least 1.times.10.sup.-4 S cm.sup.-1 at 25.degree. C.

  10. Lithium insertion in graphite from ternary ionic liquid-lithium salt electrolytes: II. Evaluation of specific capacity and cycling efficiency and stability at room temperature

    NASA Astrophysics Data System (ADS)

    Lux, Simon F.; Schmuck, Martin; Appetecchi, Giovanni B.; Passerini, Stefano; Winter, Martin; Balducci, Andrea

    In this paper we report the results about the use of ternary room temperature ionic liquid-lithium salt mixtures as electrolytes for lithium-ion battery systems. Mixtures of N-methyl- N-propyl pyrrolidinium bis(fluorosulfonyl) imide, PYR 13FSI, and N-butyl- N-methylpyrrolidinium bis(trifluoromethansulfonyl) imide, PYR 14TFSI, with lithium hexafluorophosphate, LiPF 6 and lithium bis(trifluoromethansulfonyl) imide, LiTFSI, containing 5 wt.% of vinylene carbonate (VC) as additive, have been used in combination with a commercial graphite, KS6 TIMCAL. The performance of the graphite electrodes has been considered in term of specific capacity, cycling efficiency and cycling stability. The results clearly show the advantage of the use of ternary mixtures on the performance of the graphite electrode.

  11. A high performance flexible all solid state supercapacitor based on the MnO2 sphere coated macro/mesoporous Ni/C electrode and ionic conducting electrolyte

    NASA Astrophysics Data System (ADS)

    Zhi, Jian; Reiser, Oliver; Wang, Youfu; Hu, Aiguo

    2016-06-01

    A high contact resistance between the active materials and the current collector, a low ionic conductivity of the gel electrolyte, and an impenetrable electrode structure are the three major barriers which greatly limit the capacitance of MnO2 in solid state supercapacitors. As a potential solution to these problems, in this work we report a novel electrode for solid state supercapacitors, based on a ternary system composed of hierarchical MnO2 spheres as the active material, macroporous Ni foam as gel penetrable skeletons and an ordered mesoporous carbon (OMC) membrane as the charge-transport accelerating layer. By employing butyl-3-methylimidazolium chloride (BMIMCl) modified gels as the ionic conducting electrolyte, the utilization efficiency of MnO2 on the specific capacitance was enhanced up to 88% of the theoretical value, delivering a volumetric capacitance of 81 F cm-3, which is the highest value among MnO2 based solid state supercapacitors. Moreover, such a flexible device exhibits exceptional volumetric energy and power density (6.6 Wh L-1 and 549 W L-1, based on the whole device volume) combined with a small capacity loss of 8.5% after 6000 cycles under twisting. These encouraging findings unambiguously overcome the energy bottleneck of MnO2 in solid state supercapacitors, and open up a new application of macro/mesoporous materials in flexible devices.A high contact resistance between the active materials and the current collector, a low ionic conductivity of the gel electrolyte, and an impenetrable electrode structure are the three major barriers which greatly limit the capacitance of MnO2 in solid state supercapacitors. As a potential solution to these problems, in this work we report a novel electrode for solid state supercapacitors, based on a ternary system composed of hierarchical MnO2 spheres as the active material, macroporous Ni foam as gel penetrable skeletons and an ordered mesoporous carbon (OMC) membrane as the charge-transport accelerating

  12. Visualization of Steady-State Ionic Concentration Profiles Formed in Electrolytes during Li-Ion Battery Operation and Determination of Mass-Transport Properties by in Situ Magnetic Resonance Imaging.

    PubMed

    Krachkovskiy, Sergey A; Bazak, J David; Werhun, Peter; Balcom, Bruce J; Halalay, Ion C; Goward, Gillian R

    2016-06-29

    Accurate modeling of Li-ion batteries performance, particularly during the transient conditions experienced in automotive applications, requires knowledge of electrolyte transport properties (ionic conductivity κ, salt diffusivity D, and lithium ion transference number t(+)) over a wide range of salt concentrations and temperatures. While specific conductivity data can be easily obtained with modern computerized instrumentation, this is not the case for D and t(+). A combination of NMR and MRI techniques was used to solve the problem. The main advantage of such an approach over classical electrochemical methods is its ability to provide spatially resolved details regarding the chemical and dynamic features of charged species in solution, hence the ability to present a more accurate characterization of processes in an electrolyte under operational conditions. We demonstrate herein data on ion transport properties (D and t(+)) of concentrated LiPF6 solutions in a binary ethylene carbonate (EC)-dimethyl carbonate (DMC) 1:1 v/v solvent mixture, obtained by the proposed technique. The buildup of steady-state (time-invariant) ion concentration profiles during galvanostatic experiments with graphite-lithium metal cells containing the electrolyte was monitored by pure phase-encoding single point imaging MRI. We then derived the salt diffusivity and Li(+) transference number over the salt concentration range 0.78-1.27 M from a pseudo-3D combined PFG-NMR and MRI technique. The results obtained with our novel methodology agree with those obtained by electrochemical methods, but in contrast to them, the concentration dependences of salt diffusivity and Li(+) transference number were obtained simultaneously within the single in situ experiment.

  13. Numerical study of density functional theory with mean spherical approximation for ionic condensation in highly charged confined electrolytes

    NASA Astrophysics Data System (ADS)

    Joubaud, R.; Bernard, O.; Delville, A.; Ern, A.; Rotenberg, B.; Turq, P.

    2014-06-01

    We investigate numerically a density functional theory (DFT) for strongly confined ionic solutions in the canonical ensemble by comparing predictions of ionic concentration profiles and pressure for the double-layer configuration to those obtained with Monte Carlo (MC) simulations and the simpler Poisson-Boltzmann (PB) approach. The DFT consists of a bulk (ion-ion) and an ion-solid part. The bulk part includes nonideal terms accounting for long-range electrostatic and short-range steric correlations between ions and is evaluated with the mean spherical approximation and the local density approximation. The ion-solid part treats the ion-solid interactions at the mean-field level through the solution of a Poisson problem. The main findings are that ionic concentration profiles are generally better described by PB than by DFT, although DFT captures the nonmonotone co-ion profile missed by PB. Instead, DFT yields more accurate pressure predictions than PB, showing in particular that nonideal effects are important to describe highly confined ionic solutions. Finally, we present a numerical methodology capable of handling nonconvex minimization problems so as to explore DFT predictions when the reduced temperature falls below the critical temperature.

  14. Ionic liquids as electrolytes for non-aqueous solutions electrochemical supercapacitors in a temperature range of 20 °C-80 °C

    NASA Astrophysics Data System (ADS)

    Zhang, Lei; Tsay, Ken; Bock, Christina; Zhang, Jiujun

    2016-08-01

    To increase the operating temperature of the supercapacitors (SCs) without compromising their high cycle-life, several typical fluoro- and non-fluoro containing ionic liquids (EMI-mesylate, EMI-hydrogen sulfate, PP13-triflate, PP13-TFSI, and EMI-TFSI, as shown in Fig. 1) are studied as the electrolytes to prepare organic solutions for SC performance measurements using a two-electrode cell. Both cyclic voltammograms and charge/discharge curves at various temperatures such as 20, 40, 60 and 80 °C are collected. At 60 °C, the increased performance order in both rating and cyclability measurements are found to be as follows: 1) EMI-hydrogen sulfate < PP13-TFSI < EMI-mesylate < PP13-triflate < EMI-TFSI for rating; and 2) EMI-hydrogen sulfate < EMI-mesylate < PP13-Triflate < PP13-TFSI < EMI-TFSI for life-time. The fluoro-containing group of ILs, i.e., PP13-Triflate, PP13-TFSI and EMI-TFSI can give a specific capacitance between 100 and 170 F/g for various scan rates for a conventional carbon electrode, and an extended lifetime test of 10, 000 cycles with a capacitance degradation of less than 10%, indicating that these two ion liquids can be used for SC electrolytes operated at high temperature.

  15. Electrochemical and in-situ X-ray diffraction studies of Ti3C2Tx MXene in ionic liquid electrolyte

    DOE PAGES

    Lin, Zifeng; Rozier, Patrick; Duployer, Benjamin; ...

    2016-08-26

    2D titanium carbide (Ti3C2Tx MXene) showed good capacitance in both organic and neat ionic liquid electrolytes, but its charge storage mechanism is still not fully understood. Here, electrochemical characteristics of Ti3C2Tx electrode were studied in neat EMI-TFSI electrolyte. A capacitive behavior was observed within a large electrochemical potential range (from – 1.5 to 1.5 V vs. Ag). Intercalation and de-intercalation of EMI+ cations and/or TFSI– anions were investigated by in-situ X-ray diffraction. Interlayer spacing of Ti3C2Tx flakes decreases during positive polarization, which can be ascribed to either electrostatic attraction effect between intercalated TFSI– anions and positively charged Ti3C2Tx nanosheets ormore » steric effect caused by de-intercalation of EMI+ cations. In conclusion, the expansion of interlayer spacing when polarized to negative potentials is explained by steric effect of cation intercalation.« less

  16. Two-ply yarn supercapacitor based on carbon nanotube/stainless steel core-sheath yarn electrodes and ionic liquid electrolyte

    NASA Astrophysics Data System (ADS)

    Lyu, Xiaoming; Su, Fenghua; Miao, Menghe

    2016-03-01

    Linear supercapacitors have great potential as power source in electronic textiles. However, the energy density of most yarn supercapacitors reported so far is still quite low and decreases significantly as the supercapacitor length increases. Here, we report a two-ply yarn supercapacitor based on carbon nanotube/stainless steel core-sheath yarn electrode and ionic liquid electrolyte. The use of IL gel electrolyte widens the potential window of supercapacitor from 1.0 V to 2.7 V. The carbon nanotube/stainless steel core-sheath yarn structure greatly improves the charge transport efficiency and allows the length of the linear supercapacitor to be significantly scaled up. The resulting supercapacitor has shown outstanding electrochemical performances with a high volumetric capacitance of 263.31 F cm-3 and energy density of 6.67×10-2 Wh cm-3. The two-ply yarn supercapacitors are also very flexible and strong for use as sewing thread and for making knots without significant loss of their energy storage capacity.

  17. Infiltration of Solution-Processable Solid Electrolytes into Conventional Li-Ion-Battery Electrodes for All-Solid-State Li-Ion Batteries.

    PubMed

    Kim, Dong Hyeon; Oh, Dae Yang; Park, Kern Ho; Choi, Young Eun; Nam, Young Jin; Lee, Han Ah; Lee, Sang-Min; Jung, Yoon Seok

    2017-04-05

    Bulk-type all-solid-state lithium-ion batteries (ASLBs) have the potential to be superior to conventional lithium-ion batteries (LIBs) in terms of safety and energy density. Sulfide SE materials are key to the development of bulk-type ASLBs because of their high ionic conductivity (max of ∼10(-2) S cm(-1)) and deformability. However, the severe reactivity of sulfide materials toward common polar solvents and the particulate nature of these electrolytes pose serious complications for the wet-slurry process used to fabricate ASLB electrodes, such as the availability of solvent and polymeric binders and the formation of ionic contacts and networks. In this work, we report a new scalable fabrication protocol for ASLB electrodes using conventional composite LIB electrodes and homogeneous SE solutions (Li6PS5Cl (LPSCl) in ethanol or 0.4LiI-0.6Li4SnS4 in methanol). The liquefied LPSCl is infiltrated into the tortuous porous structures of LIB electrodes and solidified, providing intimate ionic contacts and favorable ionic percolation. The LPSCl-infiltrated LiCoO2 and graphite electrodes show high reversible capacities (141 and 364 mA h g(-1)) at 0.14 mA cm(-2) (0.1 C) and 30 °C, which are not only superior to those for conventional dry-mixed and slurry-mixed ASLB electrodes but also comparable to those for liquid electrolyte cells. Good electrochemical performance of ASLBs employing the LPSCl-infiltrated LiCoO2 and graphite electrodes at 100 °C is also presented, highlighting the excellent thermal stability and safety of ASLBs.

  18. IMIDAZOLE-BASED IONIC LIQUIDS FOR USE IN POLYMER ELECTROLYTE MEMBRANE FUEL CELLS: EFFECT OF ELECTRON-WITHDRAWING AND ELECTRON-DONATING SUBSTITUENTS

    SciTech Connect

    Chang, E.; Fu, Y.; Kerr, J.

    2009-01-01

    Current polymer electrolyte membrane fuel cells (PEMFCs) require humidifi cation for acceptable proton conductivity. Development of a novel polymer that is conductive without a water-based proton carrier is desirable for use in automobiles. Imidazole (Im) is a possible replacement for water as a proton solvent; Im can be tethered to the polymer structure by means of covalent bonds, thereby providing a solid state proton conducting membrane where the solvating groups do not leach out of the fuel cell. These covalent bonds can alter the electron availability of the Im molecule. This study investigates the effects of electron-withdrawing and electron-donating substituents on the conductivity of Im complexed with methanesulfonic acid (MSA) in the form of ionic liquids. Due to the changes in the electronegativity of nitrogen, it is expected that 2-phenylimidazole (2-PhIm, electron-withdrawing) will exhibit increased conductivity compared to Im, while 2-methylimidazole (2-MeIm, electron-donating) will exhibit decreased conductivity. Three sets of ionic liquids were prepared at defi ned molar ratios: Im-MSA, 2-PhIm-MSA, and 2-MeIm- MSA. Differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and 1H-NMR were used to characterize each complex. Impedance analysis was used to determine the conductivity of each complex. Both the 2-PhIm-MSA and 2-MeIm-MSA ionic liquids were found to be less conductive than the Im-MSA complex at base-rich compositions, but more conductive at acid-rich compositions. 1H-NMR data shows a downfi eld shift of the proton on nitrogen in 2-PhIm compared to Im, suggesting that other factors may diminish the electronic effects of the electron withdrawing group at base-rich compositions. Further studies examining these effects may well result in increased conductivity for Im-based complexes. Understanding the conductive properties of Im-derivatives due to electronic effects will help facilitate the development of a new electrolyte

  19. Process intensification of biodiesel production by using microwave and ionic liquids as catalyst

    SciTech Connect

    Handayani, Prima Astuti; Abdullah; Hadiyanto, Dan

    2015-12-29

    The energy crisis pushes the development and intensification of biodiesel production process. Biodiesel is produced by transesterification of vegetable oils or animal fats and conventionally produced by using acid/base catalyst. However, the conventional method requires longer processing time and obtains lower yield of biodiesel. The microwave has been intensively used to accelerate production process and ionic liquids has been introduced as source of catalyst. This paper discusses the overview of the development of biodiesel production through innovation using microwave irradiation and ionic liquids catalyst to increase the yield of biodiesel. The potential microwave to reduce the processing time will be discussed and compared with other energy power, while the ionic liquids as a new generation of catalysts in the chemical industry will be also discussed for its use. The ionic liquids has potential to enhance the economic and environmental aspects because it has a low corrosion effect, can be recycled, and low waste form.

  20. Process intensification of biodiesel production by using microwave and ionic liquids as catalyst

    NASA Astrophysics Data System (ADS)

    Handayani, Prima Astuti; Abdullah, dan Hadiyanto

    2015-12-01

    The energy crisis pushes the development and intensification of biodiesel production process. Biodiesel is produced by transesterification of vegetable oils or animal fats and conventionally produced by using acid/base catalyst. However, the conventional method requires longer processing time and obtains lower yield of biodiesel. The microwave has been intensively used to accelerate production process and ionic liquids has been introduced as source of catalyst. This paper discusses the overview of the development of biodiesel production through innovation using microwave irradiation and ionic liquids catalyst to increase the yield of biodiesel. The potential microwave to reduce the processing time will be discussed and compared with other energy power, while the ionic liquids as a new generation of catalysts in the chemical industry will be also discussed for its use. The ionic liquids has potential to enhance the economic and environmental aspects because it has a low corrosion effect, can be recycled, and low waste form.

  1. Combination of an electrolytic pretreatment unit with secondary water reclamation processes

    NASA Technical Reports Server (NTRS)

    Wells, G. W.; Bonura, M. S.

    1973-01-01

    The design and fabrication of a flight concept prototype electrolytic pretreatment unit (EPU) and of a contractor-furnished air evaporation unit (AEU) are described. The integrated EPU and AEU potable water recovery system is referred to as the Electrovap and is capable of processing the urine and flush water of a six-man crew. Results of a five-day performance verification test of the Electrovap system are presented and plans are included for the extended testing of the Electrovap to produce data applicable to the combination of electrolytic pretreatment with most final potable water recovery systems. Plans are also presented for a program to define the design requirements for combining the electrolytic pretreatment unit with a reverse osmosis final processing unit.

  2. Charged plate in asymmetric electrolytes: One-loop renormalization of surface charge density and Debye length due to ionic correlations

    NASA Astrophysics Data System (ADS)

    Ding, Mingnan; Lu, Bing-Sui; Xing, Xiangjun

    2016-10-01

    Self-consistent field theory (SCFT) is used to study the mean potential near a charged plate inside a m :-n electrolyte. A perturbation series is developed in terms of g =4 π κ b , where b a n d 1 /κ are Bjerrum length and bare Debye length, respectively. To the zeroth order, we obtain the nonlinear Poisson-Boltzmann theory. For asymmetric electrolytes (m ≠n ), the first order (one-loop) correction to mean potential contains a secular term, which indicates the breakdown of the regular perturbation method. Using a renormalizaton group transformation, we remove the secular term and obtain a globally well-behaved one-loop approximation with a renormalized Debye length and a renormalized surface charge density. Furthermore, we find that if the counterions are multivalent, the surface charge density is renormalized substantially downwards and may undergo a change of sign, if the bare surface charge density is sufficiently large. Our results agrees with large MC simulation even when the density of electrolytes is relatively high.

  3. Structure and ionic conductivity of the solid electrolyte interphase layer on tin anodes in Na-ion batteries

    NASA Astrophysics Data System (ADS)

    Kuo, Liang-Yin; Moradabadi, Ashkan; Huang, Hsin-Fu; Hwang, Bing-Joe; Kaghazchi, Payam

    2017-02-01

    Structure, stability, and ionic conductivity of the SEI layer on Sn anodes in Na-ion batteries (NIBs) are studied using experimental and theoretical methods. Raman spectra show that the SEI layer consists of Na2O and Na2CO3, the latter becoming more dominant close to the discharged state (at 0.3 V). According to our theoretical phase diagrams, Na2O can be stable in the whole voltage range of charge/discharge (from 0.0 V to 1.90 V), but Na2CO3 can decompose under carbon and/or oxygen poor conditions, leading to the formation of Na2O. These findings are in agreement with our experimental cyclic voltammetry and Raman spectra as function of voltage. Both compounds of the SEI layer have very low ionic conductivity close to the discharge state (0.2-0.3 V), but the ionic conductivity of Na2O is much larger than that of Na2CO3 for a wide range of voltages from 0.4 V to the charge state (∼1.5 V). This work suggests that engineered artificial SEI with Na2O or naturally formed SEI in a carbon and/or oxygen poor environment can improve the conductivity of the SEI layer in NIBs.

  4. Application of ionic liquid halide nucleophilicity for the cleavage of ethers: a green protocol for the regeneration of phenols from ethers.

    PubMed

    Boovanahalli, Shanthaveerappa K; Kim, Dong Wook; Chi, Dae Yoon

    2004-05-14

    We have used the high nucleophilicity of bromide ion in the form of the ionic liquid, 1-n-butyl-3-methylimidazolium bromide ([bmim][Br]), for the nucleophilic displacement of an alkyl group to regenerate a phenol from the corresponding aryl alkyl ether. Using 2-methoxynaphthalene (1) as a model compound, we found that the combination of ionic liquid [bmim][Br] and p-toluenesulfonic acid with warming effected demethylation in 14 h, affording the desired product 2-naphthol (2) in good yield (97%). Various other protic acids (MsOH, hydrochloric acid (35%), dilute sulfuric acid (50%)) could be used as a proton source in this demethylation reaction. Under the same conditions, cleavage of alkyl alkyl ether 2-(3-methoxypropyl)naphthalene yielded mixture of corresponding 2-(3-bromopropyl)naphthalene and 2-(3-hydroxypropyl)naphthalene. Dealkylation of various aryl alkyl ethers could also be achieved using significantly reduced (i.e., stoichiometric) amounts of concentrated hydrobromic acid (47%) in the ionic liquid. Both procedures afforded the desired products in moderate to good yield; however, cleavage of aryl alkyl cyclic ether, 2,3-dihydrobenzofuran, resulted in low yield of the desired product o-2-bromoethylphenol. The convenience of this method for ether cleavage and its effectiveness using only a moderate excess of hydrobromic acid make it attractive as a green chemical method.

  5. Mixed ionic and electronic conducting ceramic membranes for hydrocarbon processing

    DOEpatents

    Van Calcar, Pamela; Mackay, Richard; Sammells, Anthony F.

    2002-01-01

    The invention relates to mixed phase materials for the preparation of catalytic membranes which exhibit ionic and electronic conduction and which exhibit improved mechanical strength compared to single phase ionic and electronic conducting materials. The mixed phase materials are useful for forming gas impermeable membranes either as dense ceramic membranes or as dense thin films coated onto porous substrates. The membranes and materials of this invention are useful in catalytic membrane reactors in a variety of applications including synthesis gas production. One or more crystalline second phases are present in the mixed phase material at a level sufficient to enhance the mechanical strength of the mixture to provide membranes for practical application in CMRs.

  6. The evidence of cathodic micro-discharges during plasma electrolytic oxidation process

    SciTech Connect

    Nominé, A.; Martin, J.; Noël, C.; Henrion, G.; Belmonte, T.; Bardin, I. V.; Kovalev, V. L.; Rakoch, A. G.

    2014-02-24

    Plasma electrolytic oxidation (PEO) processing of EV31 magnesium alloy has been carried out in fluoride containing electrolyte under bipolar pulse current regime. Unusual PEO cathodic micro-discharges have been observed and investigated. It is shown that the cathodic micro-discharges exhibit a collective intermittent behavior, which is discussed in terms of charge accumulations at the layer/electrolyte and layer/metal interfaces. Optical emission spectroscopy is used to determine the electron density (typ. 10{sup 15} cm{sup −3}) and the electron temperature (typ. 7500 K) while the role of F{sup −} anions on the appearance of cathodic micro-discharges is pointed out.

  7. Silver diffusion and ionic conduction in Ag/sub 6/I/sub 4/WO/sub 4/ solid electrolyte

    SciTech Connect

    Vlasov, Yu.G.; Ermolenko, Yu.E.; Glazunov, S.V.; Kolodnikov, V.V.

    1987-08-01

    This paper studies the diffusion of silver (Ag/sup 110m/) and the Haven ratio found for the first time at temperatures between 110 and 190/sup 0/C. A mixture of the salts AgI and Ag/sub 2/WO/sub 4/ (molar ratio) was obtained by joint precipitation with silver nitrate from solutions containing stoichiometric amounts of sodium iodide and tungstate. The conductivity and diffusion of the silver radiotracer Ag/sup 110m/ in solid electrolytes of the alpha-AgI type are measured. The activity distributions in the samples after homogenizing and the temperature dependence of the diffusion coefficients are shown.

  8. Robust cycling of Li-O2 batteries through the synergistic effect of blended electrolytes.

    PubMed

    Kim, Byung Gon; Lee, Je-Nam; Lee, Dong Jin; Park, Jung-Ki; Choi, Jang Wook

    2013-03-01

    Despite their exceptionally large specific capacities, the use of Li-O2 batteries has been limited because of their poor cycle lives, which originates from irreversible reaction processes during each cycle. Recent investigations have found that electrolyte decomposition is one of the most critical reasons for capacity decay. Herein, we report that a blended electrolyte, consisting of a carbonate solvent and an ionic liquid, improves the cycle lives of Li-O2 batteries remarkably through a synergistic effect from both components. Both electrolyte components perform complementary functions to each other: The ionic liquid suppresses the decomposition of the carbonate solvent, and the carbonate solvent resolves the poor ionic conductivity of the ionic liquid. This study confirms the importance and opportunities for the use of electrolytes in Li-O2 batteries.

  9. Electrolytic regeneration of acid cupric chloride printed circuit board etchant. Quarterly report No. 4, April 30, 1996--July 30, 1996

    SciTech Connect

    Oxley, J.E.; Smialek, R.J.

    1996-08-30

    Tests on T&G Corp. proton selective membranes showed significant ion migration, so no membrane is yet on hand that will allow demonstration of oxygen ingress compensation with the pre-prototype scale regenerator. T&G is remaking a 14118 membrane, the membrane type that was used in successful bench scale testing several years ago. Modifications for pressurized operation of the pre-prototype scale plating cell were successful; the unit can withstand 8 psig pressure without leaking.

  10. Pollination and seed dispersal are the most threatened processes of plant regeneration

    NASA Astrophysics Data System (ADS)

    Neuschulz, Eike Lena; Mueller, Thomas; Schleuning, Matthias; Böhning-Gaese, Katrin

    2016-07-01

    Plant regeneration is essential for maintaining forest biodiversity and ecosystem functioning, which are globally threatened by human disturbance. Here we present the first integrative meta-analysis on how forest disturbance affects multiple ecological processes of plant regeneration including pollination, seed dispersal, seed predation, recruitment and herbivory. We analysed 408 pairwise comparisons of these processes between near-natural and disturbed forests. Human impacts overall reduced plant regeneration. Importantly, only processes early in the regeneration cycle that often depend on plant-animal interactions, i.e. pollination and seed dispersal, were negatively affected. Later processes, i.e. seed predation, recruitment and herbivory, showed overall no significant response to human disturbance. Conserving pollination and seed dispersal, including the animals that provide these services to plants, should become a priority in forest conservation efforts globally.

  11. Pollination and seed dispersal are the most threatened processes of plant regeneration

    PubMed Central

    Neuschulz, Eike Lena; Mueller, Thomas; Schleuning, Matthias; Böhning-Gaese, Katrin

    2016-01-01

    Plant regeneration is essential for maintaining forest biodiversity and ecosystem functioning, which are globally threatened by human disturbance. Here we present the first integrative meta-analysis on how forest disturbance affects multiple ecological processes of plant regeneration including pollination, seed dispersal, seed predation, recruitment and herbivory. We analysed 408 pairwise comparisons of these processes between near-natural and disturbed forests. Human impacts overall reduced plant regeneration. Importantly, only processes early in the regeneration cycle that often depend on plant-animal interactions, i.e. pollination and seed dispersal, were negatively affected. Later processes, i.e. seed predation, recruitment and herbivory, showed overall no significant response to human disturbance. Conserving pollination and seed dispersal, including the animals that provide these services to plants, should become a priority in forest conservation efforts globally. PMID:27435026

  12. Toward First Principles Prediction of Voltage Dependences of Electrolyte/Electrolyte Interfacial Processes in Lithium Ion Batteries

    SciTech Connect

    Leung, Kevin; Tenney, Craig M.

    2013-11-21

    In lithium ion batteries, Li+ intercalation into electrodes is induced by applied voltages, which are in turn associated with free energy changes of Li+ transfer (ΔGt) between the solid and liquid phases. Using ab initio molecular dynamics (AIMD) and thermodynamic integration techniques, we compute ΔGt for the virtual transfer of a Li+ from a LiC6 anode slab, with pristine basal planes exposed, to liquid ethylene carbonate confined in a nanogap. The onset of delithiation, at ΔGt = 0, is found to occur on LiC6 anodes with negatively charged basal surfaces. These negative surface charges are evidently needed to retain Li+ inside the electrode and should affect passivation (“SEI”) film formation processes. Fast electrolyte decomposition is observed at even larger electron surface densities. By assigning the experimentally known voltage (0.1 V vs Li+/Li metal) to the predicted delithiation onset, an absolute potential scale is obtained. This enables voltage calibrations in simulation cells used in AIMD studies and paves the way for future prediction of voltage dependences in interfacial processes in batteries.

  13. Structure, ion transport, and relaxation dynamics of polyethylene oxide/poly (vinylidene fluoride co-hexafluoropropylene)—lithium bis(trifluoromethane sulfonyl) imide blend polymer electrolyte embedded with ionic liquid

    NASA Astrophysics Data System (ADS)

    Das, S.; Ghosh, A.

    2016-03-01

    We have studied structure, ion transport, and relaxation dynamics in polyethylene oxide/poly (vinylidene fluoride-hexafluoropropylene)-lithium bis(trifluoromethane)sulfonimide blend polymer electrolytes embedded with 1-propyl-3-methyleimidazoliuum bis(trifluromethyle-sulfonyl)imide ionic liquid. Structural property and ion-polymer interaction of polymer electrolytes have been studied using X-ray diffraction and Raman spectroscopy. The addition of ionic liquid decreases glass transition temperature and reduces crystalline phase in the polymer matrix. It is also observed that surface becomes smooth with increase of ionic liquid content. The temperature dependence of the Li ion conductivity follows Vogel-Tammann-Fulcher type behaviour when a sufficient amount of ionic liquid is added to polymer matrix. The electric modulus has been studied using Havriliak-Negami function for the understanding of ion dynamics. The modulus data have been analyzed using non-exponential Kohlrausch-Williams-Watts function. It is observed that the non-exponential parameter β is quite lower than unity, suggesting existence of a non-exponential relaxation. The temperature dependence of the relaxation time also follows Vogel-Tammann-Fulcher relation for compositions with higher ionic liquid content.

  14. Ionic Borate-Based Covalent Organic Frameworks: Lightweight Porous Materials for Lithium-Stable Solid State Electrolytes

    SciTech Connect

    Black, Hayden T.; Harrison, Katharine Lee

    2016-10-01

    The synthesis and characterization of the first polyelectrolyte of intrinsic microporosity (PEIM) is described. The novel material was synthesized via reaction between the nitrile group in the polymer backbone and n-butyl lithium, effectively anchoring an imine anion to the porous framework while introducing a mobile lithium counterion. The PEIM was characterized by 13C, 1H, and 7Li NMR experiments, revealing quantitative conversion of the nitrile functionality to the anionic imine. Variable temperature 7Li NMR analysis of the dry PEIM and the electrolyteswollen PEIM revealed that lithium ion transport within the dry PEIM was largely due to interchain hopping of the Li+ ions, and that the mobility of polymer associated Li+ was reduced after swelling in electrolyte solution. Meanwhile, the swollen PEIM supported efficient transport of dissolved Li+ within the expanded pores. These results are discussed in the context of developing novel solid or solid-like lithium ion electrolytes using the new PEIM material.

  15. Ionic liquid effects on a multistep process. Increased product formation due to enhancement of all steps.

    PubMed

    Keaveney, Sinead T; Haines, Ronald S; Harper, Jason B

    2015-09-07

    The reaction of a series of substituted benzaldehydes with hexylamine was examined in acetonitrile and an ionic liquid. In acetonitrile, as the electron withdrawing nature of the substituent increases, the overall addition-elimination process becomes faster as does the build-up of the aminol intermediate. Under equivalent conditions in an ionic liquid, less intermediate build up is observed, and the effect on the rate on varying the substituent is different to that in acetonitrile. Extensive kinetic analysis shows that the ionic liquid solvent increases the rate constant of all steps of the reaction, resulting in faster product formation relative to acetonitrile; these effects increase with the proportion of ionic liquid in the reaction mixture. Differences in the equilibrium position of the addition step in the ionic liquid were found to account for both the decrease in intermediate build up relative to acetonitrile, as well as the differing trend in the overall rate of product formation as the substituent was changed. The microscopic origins of these ionic liquid effects were probed through temperature dependent analyses, highlighting the subtle balance of interactions between the ionic liquid and species along the reaction coordinate, particularly the importance of charge development in the transition state.

  16. Comparison of electrolytic, thermochemical, and other hydrogen-production processes

    SciTech Connect

    Carty, R.; Whaley, T.

    1981-01-01

    An overview is presented of the following six hydrogen production process categories: catalytic steam reforming of light hydrocarbons; partial oxidation of less-reactive feedstocks such as coal and heavy oil; reaction of active metals or metal hydrides with water or acids; electrolysis of water; thermochemical hydrogen cycles; and photolysis of water. These processes are compared technically, and to the extent possible, economically.

  17. Solid polymer electrolyte from phosphorylated chitosan

    SciTech Connect

    Fauzi, Iqbal Arcana, I Made

    2014-03-24

    Recently, the need of secondary battery application continues to increase. The secondary battery which using a liquid electrolyte was indicated had some weakness. A solid polymer electrolyte is an alternative electrolytes membrane which developed in order to replace the liquid electrolyte type. In the present study, the effect of phosphorylation on to polymer electrolyte membrane which synthesized from chitosan and lithium perchlorate salts was investigated. The effect of the component’s composition respectively on the properties of polymer electrolyte, was carried out by analyzed of it’s characterization such as functional groups, ion conductivity, and thermal properties. The mechanical properties i.e tensile resistance and the morphology structure of membrane surface were determined. The phosphorylation processing of polymer electrolyte membrane of chitosan and lithium perchlorate was conducted by immersing with phosphoric acid for 2 hours, and then irradiated on a microwave for 60 seconds. The degree of deacetylation of chitosan derived from shrimp shells was obtained around 75.4%. Relative molecular mass of chitosan was obtained by viscometry method is 796,792 g/mol. The ionic conductivity of chitosan membrane was increase from 6.33 × 10{sup −6} S/cm up to 6.01 × 10{sup −4} S/cm after adding by 15 % solution of lithium perchlorate. After phosphorylation, the ionic conductivity of phosphorylated lithium chitosan membrane was observed 1.37 × 10{sup −3} S/cm, while the tensile resistance of 40.2 MPa with a better thermal resistance. On the strength of electrolyte membrane properties, this polymer electrolyte membrane was suggested had one potential used for polymer electrolyte in field of lithium battery applications.

  18. Low-cost method for sodium borohydride regeneration and the energy efficiency of its hydrolysis and regeneration process

    NASA Astrophysics Data System (ADS)

    Ouyang, L. Z.; Zhong, H.; Li, Z. M.; Cao, Z. J.; Wang, H.; Liu, J. W.; Zhu, X. K.; Zhu, M.

    2014-12-01

    Hydrolysis of sodium borohydride (NaBH4) is one of the most attractive methods for energy generation of mobile systems used as hydrogen source because of the high gravimetric density and controllable hydrogen generation of NaBH4. However, regeneration of NaBH4 is a key issue that remains to be solved, and the energy efficiency of NaBH4 is unknown. In the present study, the energy efficiency of NaBH4 hydrolysis and the entire process of sodium metaborate (NaBO2) regeneration via reaction with magnesium hydride (MgH2) is determined through thermodynamics calculations. The maximum energy efficiency is 49.91%, indicating that NaBH4 generation by reaction between MgH2 and NaBO2 during ball milling is feasible. An inexpensive high-energy ball milling method is employed to regenerate NaBH4 by reaction of NaBO2 with magnesium-lanthanum hydrides (H-Mg3La). Products after ball milling are characterized through Fourier transform infrared spectroscopy and X-ray diffraction measurements. In the reaction of NaBO2 with H-Mg3La, MgH2 reacts with NaBO2 and then lanthanum hydride (LaH3) reacts with NaBO2 to produce NaBH4.

  19. Plasticizing effect of ionic liquid on cellulose acetate obtained by melt processing.

    PubMed

    Bendaoud, Amine; Chalamet, Yvan

    2014-08-08

    Cellulose acetate (CA) plasticized by 1-butyl-3-methylimidazolium chloride (BMIMCl) and with diethylphtalate (DEP) was obtained by melt processing at 150°C. The effect and the interaction of ionic liquid with the cellulose acetate and their influence on structural, thermo-mechanical, rheological and tensile properties of CA materials were investigated. Ionic liquid (BMIMCl) has shown a good plasticization and more efficient destruction of the crystalline structure of cellulose acetate than the DEP plasticized CA. BMIMCl interacts intensively with CA molecules due to the pronounced van der Waals interactions, hydrogen bonding and electrostatic nature of ionic liquid. The tensile test and the low Young's modulus for plasticized CA suggest a strong reduction of the interaction between the CA chains due to the presence of the ionic liquid.

  20. Poly(ethylene oxide)-co-poly(propylene oxide)-based gel electrolyte with high ionic conductivity and mechanical integrity for lithium-ion batteries.

    PubMed

    Wang, Shih-Hong; Hou, Sheng-Shu; Kuo, Ping-Lin; Teng, Hsisheng

    2013-09-11

    Using gel polymer electrolytes (GPEs) for lithium-ion batteries usually encounters the drawback of poor mechanical integrity of the GPEs. This study demonstrates the outstanding performance of a GPE consisting of a commercial membrane (Celgard) incorporated with a poly(ethylene oxide)-co-poly(propylene oxide) copolymer (P(EO-co-PO)) swelled by a liquid electrolyte (LE) of 1 M LiPF6 in carbonate solvents. The proposed GPE stably holds LE with an amount that is three times that of the Celgard-P(EO-co-PO) composite. This GPE has a higher ionic conductivity (2.8×10(-3) and 5.1×10(-4) S cm(-1) at 30 and -20 °C, respectively) and a wider electrochemical voltage range (5.1 V) than the LE-swelled Celgard because of the strong ion-solvation power of P(EO-co-PO). The active ion-solvation role of P(EO-co-PO) also suppresses the formation of the solid-electrolyte interphase layer. When assembling the GPE in a Li/LiFePO4 battery, the P(EO-co-PO) network hinders anionic transport, producing a high Li+ transference number of 0.5 and decreased the polarization overpotential. The Li/GPE/LiFePO4 battery delivers a discharge capacity of 156-135 mAh g(-1) between 0.1 and 1 C-rates, which is approximately 5% higher than that of the Li/LE/LiFePO4 battery. The IR drop of the Li/GPE/LiFePO4 battery was 44% smaller than that of the Li/LE/LiFePO4. The Li/GPE/LiFePO4 battery is more stable, with only a 1.2% capacity decay for 150 galvanostatic charge-discharge cycles. The advantages of the proposed GPE are its high stability, conductivity, Li+ transference number, and mechanical integrity, which allow for the assembly of GPE-based batteries readily scalable to industrial levels.

  1. Electrocatalytic activities of cathode electrodes for water electrolysis using tetra-alkyl-ammonium-sulfonic acid ionic liquid as electrolyte

    NASA Astrophysics Data System (ADS)

    Fiegenbaum, Fernanda; de Souza, Michèle O.; Becker, Márcia R.; Martini, Emilse M. A.; de Souza, Roberto F.

    2015-04-01

    The hydrogen evolution reaction (HER) performed with platinum (Pt), nickel (Ni), stainless steel 304 (SS) or glassy carbon (GC) cathodes in 0.1 M 3-triethylammonium-propanesulfonic acid tetrafluoroborate (TEA-PS.BF4) solution is studied using quasi-potentiostatic and impedance spectroscopy techniques. The objective is to compare the catalytic effect on the cathode using different materials to obtain hydrogen by water electrolysis. Furthermore, the catalytic effect of the ionic liquid (IL) on the cathode compared with that of a hydrochloric acid (HCl) solution with same pH value (0.8) is reported. A low activation energy (Ea) of 8.7 kJ mol-1 is found for the glassy carbon cathode. Tafel plots obtained with TEA-PS.BF4 IL suggest the formation of an electroactive layer of IL on the cathode, which may be responsible for the catalytically enhanced performance observed.

  2. Electric fish: new insights into conserved processes of adult tissue regeneration.

    PubMed

    Unguez, Graciela A

    2013-07-01

    Biology is replete with examples of regeneration, the process that allows animals to replace or repair cells, tissues and organs. As on land, vertebrates in aquatic environments experience the occurrence of injury with varying frequency and to different degrees. Studies demonstrate that ray-finned fishes possess a very high capacity to regenerate different tissues and organs when they are adults. Among fishes that exhibit robust regenerative capacities are the neotropical electric fishes of South America (Teleostei: Gymnotiformes). Specifically, adult gymnotiform electric fishes can regenerate injured brain and spinal cord tissues and restore amputated body parts repeatedly. We have begun to identify some aspects of the cellular and molecular mechanisms of tail regeneration in the weakly electric fish Sternopygus macrurus (long-tailed knifefish) with a focus on regeneration of skeletal muscle and the muscle-derived electric organ. Application of in vivo microinjection techniques and generation of myogenic stem cell markers are beginning to overcome some of the challenges owing to the limitations of working with non-genetic animal models with extensive regenerative capacity. This review highlights some aspects of tail regeneration in S. macrurus and discusses the advantages of using gymnotiform electric fishes to investigate the cellular and molecular mechanisms that produce new cells during regeneration in adult vertebrates.

  3. Electric fish: new insights into conserved processes of adult tissue regeneration

    PubMed Central

    Unguez, Graciela A.

    2013-01-01

    Summary Biology is replete with examples of regeneration, the process that allows animals to replace or repair cells, tissues and organs. As on land, vertebrates in aquatic environments experience the occurrence of injury with varying frequency and to different degrees. Studies demonstrate that ray-finned fishes possess a very high capacity to regenerate different tissues and organs when they are adults. Among fishes that exhibit robust regenerative capacities are the neotropical electric fishes of South America (Teleostei: Gymnotiformes). Specifically, adult gymnotiform electric fishes can regenerate injured brain and spinal cord tissues and restore amputated body parts repeatedly. We have begun to identify some aspects of the cellular and molecular mechanisms of tail regeneration in the weakly electric fish Sternopygus macrurus (long-tailed knifefish) with a focus on regeneration of skeletal muscle and the muscle-derived electric organ. Application of in vivo microinjection techniques and generation of myogenic stem cell markers are beginning to overcome some of the challenges owing to the limitations of working with non-genetic animal models with extensive regenerative capacity. This review highlights some aspects of tail regeneration in S. macrurus and discusses the advantages of using gymnotiform electric fishes to investigate the cellular and molecular mechanisms that produce new cells during regeneration in adult vertebrates. PMID:23761473

  4. Physicochemical and porosity characteristics of thermally regenerated activated carbon polluted with biological activated carbon process.

    PubMed

    Dong, Lihua; Liu, Wenjun; Jiang, Renfu; Wang, Zhansheng

    2014-11-01

    The characteristics of thermally regenerated activated carbon (AC) polluted with biological activated carbon (BAC) process were investigated. The results showed that the true micropore and sub-micropore volume, pH value, bulk density, and hardness of regenerated AC decreased compared to the virgin AC, but the total pore volume increased. XPS analysis displayed that the ash contents of Al, Si, and Ca in the regenerated AC respectively increased by 3.83%, 2.62% and 1.8%. FTIR spectrum showed that the surface functional groups of virgin and regenerated AC did not change significantly. Pore size distributions indicated that the AC regeneration process resulted in the decrease of micropore and macropore (D>10 μm) volume and the increase of mesopore and macropore (0.1 μmregenerated AC, which are benefit for water treatment. These results will provide a theoretical basis for the reuse of biological waste (spent AC) from BAC process.

  5. Effects of 12-Crown-4 ether on the ionic conductivity and electrode kinetics of electrolytes in polyethylene oxide

    NASA Technical Reports Server (NTRS)

    Nagasubramanian, G.; Di Stefano, S.

    1990-01-01

    Results are described of investigations of the electrical and electrochemical properties of thin films of polyethylene oxide (PEO) electrolytes with and without 12-Crown-4 ether (12Cr4) as a function of temperature and in the frequency regime 100 kHz-0.1 Hz. These measurements were made for LiCF3SO3, LiBF4, and LiClO4 salts. At a given temperature, the bulk conductivity, sigma, (S/cm), for a particular salt, depends on the 12Cr4 concentration with sigma reaching a maximum at about 3 mM 12Cr4. Of the three salts studied, the sigma is the highest for PEO/LiBF4 with 3 mM 12Cr4. The ac and dc measurements yield a lower charge transfer resistance for 12Cr4-incorporated samples than for samples without. Plating/stripping of Li occurs at a potential closer to Li(+)/Li for 12Cr4 samples than those without. The conductivities of a thin (about 100 microns) and a thick (400 microns) films are similar.

  6. Effects of TiO2 addition on ionic conductivity of PVC/PEMA blend based composite polymer electrolyte

    NASA Astrophysics Data System (ADS)

    Subban, R. H. Y.; Sukri, Nursyazwani

    2015-08-01

    PVC/PEMA blend based polymer electrolytes with lithium bistrifluoromethane sulfonimide (LiN(CF3SO2)2) and PVC/PEMA/(LiN(CF3SO2)2-TiO2 films were prepared by solution cast technique. The sample containing 35 wt. % LiN(CF3SO2)2 exhibited the highest conductivity of 1.75 × 10-5 Scm-1. The conductivity of the sample increased to 2.12 × 10-5 Scm-1 and 4.61 × 10-5 Scm-1 when 4 wt. % and 10 wt. % of titanium dioxide (TiO2) was added to the sample at 65 wt. % PVC/PEMA-35 wt. % LiN(CF3SO2)2 composition respectively. The low increase in conductivity is attributed to two competing factors: increase in crystallinity as accounted by X-Ray diffraction (XRD) and decrease in glass transition temperature as accounted by differential scanning calorimetry (DSC).

  7. Effects of TiO{sub 2} addition on ionic conductivity of PVC/PEMA blend based composite polymer electrolyte

    SciTech Connect

    Subban, R. H. Y.; Sukri, Nursyazwani

    2015-08-28

    PVC/PEMA blend based polymer electrolytes with lithium bistrifluoromethane sulfonimide (LiN(CF{sub 3}SO{sub 2}){sub 2}) and PVC/PEMA/(LiN(CF{sub 3}SO{sub 2}){sub 2}-TiO{sub 2} films were prepared by solution cast technique. The sample containing 35 wt. % LiN(CF{sub 3}SO{sub 2}){sub 2} exhibited the highest conductivity of 1.75 × 10{sup −5} Scm{sup −1}. The conductivity of the sample increased to 2.12 × 10{sup −5} Scm{sup −1} and 4.61 × 10{sup −5} Scm{sup −1} when 4 wt. % and 10 wt. % of titanium dioxide (TiO{sub 2}) was added to the sample at 65 wt. % PVC/PEMA-35 wt. % LiN(CF{sub 3}SO{sub 2}){sub 2} composition respectively. The low increase in conductivity is attributed to two competing factors: increase in crystallinity as accounted by X-Ray diffraction (XRD) and decrease in glass transition temperature as accounted by differential scanning calorimetry (DSC)

  8. Electrochemical performance of 0.5Li2MnO3-0.5Li(Mn0.375Ni0.375Co0.25)O2 composite cathode in pyrrolidinium-based ionic liquid electrolytes

    NASA Astrophysics Data System (ADS)

    Patra, Jagabandhu; Dahiya, Prem Prakash; Tseng, Chung-Jen; Fang, Jason; Lin, Yu-Wei; Basu, S.; Majumder, S. B.; Chang, Jeng-Kuei

    2015-10-01

    High-energy-density 0.5Li2MnO3-0.5Li(Mn0.375Ni0.375Co0.25)O2 composite cathodes for lithium rechargeable batteries are synthesized using an auto-combustion method. The electrode charge-discharge properties are studied at 25 and 50 °C in Li+-containing N-butyl-N-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide (BMP-TFSI) and N-propyl-N-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide (PMP-TFSI) ionic liquid (IL) electrolytes. The IL electrolytes have a high decomposition temperature (∼400 °C) and thus are ideal for high-safety applications. Compared to Li+/BMP-TFSI IL, Li+/PMP-TFSI IL exhibits higher ionic conductivity and lower viscosity. As a result, the composite cathode shows superior electrochemical performance in Li+/PMP-TFSI IL electrolyte. With the increase in cell temperature from 25 to 50 °C, the maximum capacities and rate capabilities of both IL cells improve significantly. Thus at 50 °C, discharge capacities of 304 mAh g-1 (@10 mA g-1) and 223 mAh g-1 (@100 mA g-1) are obtained for the Li+/PMP-TFSI cell. These capacities are superior to those for a control cell made with the same composite cathode and a conventional organic electrolyte. At elevated temperature, the cyclability of the composite cathode in the IL electrolytes is markedly higher than that obtained in a conventional organic electrolyte.

  9. A binary ionic liquid system composed of N-methoxyethyl- N-methylpyrrolidinium bis(trifluoromethanesulfonyl)-imide and lithium bis(trifluoromethanesulfonyl)imide: A new promising electrolyte for lithium batteries

    NASA Astrophysics Data System (ADS)

    Ferrari, S.; Quartarone, E.; Mustarelli, P.; Magistris, A.; Protti, S.; Lazzaroni, S.; Fagnoni, M.; Albini, A.

    Room temperature ionic liquids are nowadays the most appealing research target in the field of liquid electrolytes for lithium batteries, due to their high thermal stability, ionic conductivity and wide electrochemical windows. The cation structure of such solvents strictly influences their physical and chemical properties, in particular the viscosity and conductivity. In this paper we report on the preparation and characterization of a complete series of solutions between lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and the promising N-methoxyethyl- N-methylpyrrolidinium bis(trifluoromethanesulfonyl)-imide (PY 1,2O1) ionic liquid. A wide molality range has been explored in order to identify the optimal compositions in terms of conductivity and electrochemical stability. Our thermal results show that the solutions are amorphous independently on the LiTFSI content. Up to salt concentration of 0.4 mol kg -1 the solutions have a very low viscosity (η ∼ 36 cP), a high ionic conductivity, even at temperatures below 0 °C, and a good electrochemical stability. Cations transport numbers ranging between 0.05 and 0.39 have been determined as a function of LiTFSI content. The combination of these properties makes the PY 1,2O1-based solutions potentially attractive liquid electrolytes for lithium batteries.

  10. Integrated study of first principles calculations and experimental measurements for Li-ionic conductivity in Al-doped solid-state LiGe2(PO4)3 electrolyte

    NASA Astrophysics Data System (ADS)

    Kang, Joonhee; Chung, Habin; Doh, Chilhoon; Kang, Byoungwoo; Han, Byungchan

    2015-10-01

    Understanding of the fundamental mechanisms causing significant enhancement of Li-ionic conductivity by Al3+ doping to a solid LiGe2(PO4)3 (LGP) electrolyte is pursued using first principles density functional theory (DFT) calculations combined with experimental measurements. Our results indicate that partial substitution Al3+ for Ge4+ in LiGe2(PO4)3 (LGP) with aliovalent (Li1+xAlxGe2-x(PO4)3, LAGP) improves the Li-ionic conductivity about four-orders of the magnitude. To unveil the atomic origin we calculate plausible diffusion paths of Li in LGP and LAGP materials using DFT calculations and a nudged elastic band method, and discover that LAGP had additional transport paths for Li with activation barriers as low as only 34% of the LGP. Notably, these new atomic channels manifest subtle electrostatic environments facilitating cooperative motions of at least two Li atoms. Ab-initio molecular dynamics predict Li-ionic conductivity for the LAGP system, which is amazingly agreed experimental measurement on in-house made samples. Consequently, we suggest that the excess amounts of Li caused by the aliovalent Al3+ doping to LGP lead to not only enhancing Li concentration but also opening new conducting paths with substantially decreases activation energies and thus high ionic conductivity of LAGP solid-state electrolyte.

  11. Transport properties and phase behaviour in binary and ternary ionic liquid electrolyte systems of interest in lithium batteries.

    PubMed

    Bayley, Paul M; Best, Adam S; MacFarlane, Douglas R; Forsyth, Maria

    2011-03-14

    A binary ionic liquid (IL) system based on a common cation, N-methyl-N-propylpyrrolidinium (C(3) mpyr(+)), and either bis(trifluoromethanesulfonyl)imide (NTf(2) (-)) or bis(fluorosulfonyl) imide (FSI(-) as the anion is explored over its entire composition range. Phase behavior, determined by DSC, shows the presence of a eutectic temperature at 247 K and composition around an anion ratio of 2:1 (FSI(-) :NTf(2)(-)) with the phase diagram for this system proposed (under the thermal conditions used). Importantly for electrochemical devices, the single phase melting transition at the eutectic is well below ambient temperatures (247 K). To investigate the effect of such anion mixing on the lithium ion speciation, conductivity and PFG-NMR diffusion measurements were performed in both the binary IL system as well as the Li-NTf(2) -containing ternary system. The addition of the lithium salt to the mixed IL system resulted in a decrease in conductivity, as is commonly observed in the single-component IL systems. For a fixed lithium salt composition, both conductivity and ion diffusion have linear behaviour as a function of the anion ratio, however, the rate of change of the diffusion coefficient seems greater in the presence of lithium. From the application point of view, the addition of the FSI(-) to the NTf(2)(-) IL results in a considerable increase in lithium ion diffusivity at room temperature and no evidence of additional complex ion behaviour.

  12. Secondary zinc/oxygen electrochemical cells using inorganic oxyacid electrolytes

    SciTech Connect

    Blurton, I.F.; Sammells, A.F.

    1980-09-02

    A secondary zinc/oxygen electrochemical cell is described that uses a circulating aqueous inorganic oxyacid electrolyte and has an external load circuit or charging circuit in electronic communication with the anode and cathode, the circuit being completed by ionic interaction through an ionic separator between the catholyte and anolyte. The electrochemical cell of this invention provides a process for production of electricity and may be recharged by providing electrical energy from the external circuit.

  13. Regeneration of siloxane-exhausted activated carbon by advanced oxidation processes.

    PubMed

    Cabrera-Codony, Alba; Gonzalez-Olmos, Rafael; Martín, Maria J

    2015-03-21

    In the context of the biogas upgrading, siloxane exhausted activated carbons need to be regenerated in order to avoid them becoming a residue. In this work, two commercial activate carbons which were proved to be efficient in the removal of octamethylcyclotetrasiloxane (D4) from biogas, have been regenerated through advanced oxidation processes using both O3 and H2O2. After the treatment with O3, the activated carbon recovered up to 40% of the original adsorption capacity while by the oxidation with H2O2 the regeneration efficiency achieved was up to 45%. In order to enhance the H2O2 oxidation, activated carbon was amended with iron. In this case, the regeneration efficiency increased up to 92%.

  14. Photo-induced regeneration of hormones by electron transfer processes: Potential biological and medical consequences

    NASA Astrophysics Data System (ADS)

    Getoff, Nikola; Hartmann, Johannes; Schittl, Heike; Gerschpacher, Marion; Quint, Ruth Maria

    2011-08-01

    Based on the previous results concerning electron transfer processes in biological substances, it was of interest to investigate if hormone transients resulting by e.g. electron emission can be regenerated. The presented results prove for the first time that the hormone transients originating by the electron emission process can be successfully regenerated by the transfer of electrons from a potent electron donor, such as vitamin C (VitC). Investigations were performed using progesterone (PRG), testosterone (TES) and estrone (E1) as representatives of hormones. By irradiation with monochromatic UV light (λ=254 nm) in a media of 40% water and 60% ethanol, the degradation as well as the regeneration of the hormones was studied with each hormone individually and in the mixture with VitC as a function of the absorbed UV dose, using HPLC. Calculated from the obtained initial yields, the determined regeneration of PRG amounted to 52.7%, for TES to 58.6% and for E1 to 90.9%. The consumption of VitC was determined in the same way. The reported results concerning the regeneration of hormones by the transfer of electrons from an electron donor offer a new, promising method for the therapy with hormones. As a consequence of the regeneration of hormones, a decreased formation of carcinogenic metabolites is expected.

  15. Co-electroosmotic capillary electrophoresis of basic proteins with 1-alkyl-3-methylimidazolium tetrafluoroborate ionic liquids as non-covalent coating agents of the fused-silica capillary and additives of the electrolyte solution.

    PubMed

    Corradini, Danilo; Nicoletti, Isabella; Bonn, Günther K

    2009-06-01

    The paper reports the results of a study carried out to evaluate the use of three 1-alkyl-3-methylimidazolium-based ionic liquids as non-covalent coating agents for bare fused-silica capillaries and additives of the electrolyte solutions (BGE) for CE of basic proteins in the co-EOF separation mode. The three ionic liquids are differentiated from each other by the length of the alkyl group on the imidazolium cation, consisting of either an ethyl, butyl or octyl substituent, whereas tetrafluoroborate is the common anionic component of the ionic liquids. Coating the capillary with the ionic liquid resulted in improved peak shape and protein separation, while the EOF was maintained cathodic. This indicates that each ionic liquid is effective at masking the protein interaction sites on the inner surface of the capillary, also when its adsorption onto the capillary wall has not completely neutralized all the negative charges arising from the ionization of the silanol groups and the ionic liquid is not incorporated into the BGE employed for separation. Using the coated capillaries with BGE containing the ionic liquid employed for the coating, at concentration low enough to maintaining the EOF cathodic, both peak shape and protein separation varied to different extents, based on the particular ionic liquid used and its concentration. Fast and efficient separation of the model basic protein mixture in co-electroosmotic CE is obtained with the 1-butyl-3-methylimidazolium tetrafluoroborate coated capillary and 100 mM acetate buffer (pH 4.0) containing 4.4 mM 1-butyl-3-methylimidazolium tetrafluoroborate as the BGE.

  16. Solid-state supercapacitors with ionic liquid gel polymer electrolyte based on poly (3, 4-ethylenedioxythiophene), carbon nanotubes, and metal oxides nanocomposites for electrical energy storage

    NASA Astrophysics Data System (ADS)

    Obeidat, Amr M.

    Clean and renewable energy systems have emerged as an important area of research having diverse and significant new applications. These systems utilize different energy storage methods such as the batteries and supercapacitors. Supercapacitors are electrochemical energy storage devices that are designed to bridge the gap between batteries and conventional capacitors. Supercapacitors which store electrical energy by electrical double layer capacitance are based on large surface area structured carbons. The materials systems in which the Faradaic reversible redox reactions store electrical energy are the transition metal oxides and electronically conducting polymers. Among the different types of conducting polymers, poly (3, 4- ethylenedioxythiophene) (PEDOT) is extensively investigated owing to its chemical and mechanical stability. Due to instability of aqueous electrolytes at high voltages and toxicity of organic electrolytes, potential of supercapacitors has not been fully exploited. A novel aspect of this work is in utilizing the ionic liquid gel polymer electrolyte to design solid-state supercapacitors for energy storage. Various electrochemical systems were investigated including graphene, PEDOT, PEDOT-carbon nanotubes, PEDOT-manganese oxide, and PEDOT-iron oxide nanocomposites. The electrochemical performance of solid-state supercapacitor devices was evaluated based on cyclic voltammetry (CV), charge-discharge (CD), prolonged cyclic tests, and electrochemical impedance spectroscopy (EIS) techniques. Raman spectroscopy technique was also utilized to analyze the bonding structure of the electrode materials. The graphene solid-state supercapacitor system displayed areal capacitance density of 141.83 mF cm-2 based on high potential window up to 4V. The PEDOT solid-state supercapacitor system was synthesized in acetonitrile and aqueous mediums achieving areal capacitance density of 219.17 mF cm-2. The hybrid structure of solid-state supercapacitors was also

  17. Li2OHCl crystalline electrolyte for stable metallic lithium anodes

    DOE PAGES

    Hood, Zachary D.; Wang, Hui; Samuthira Pandian, Amaresh; ...

    2016-01-22

    In a classic example of stability from instability, we show that Li2OHCl solid electrolyte forms a stable solid electrolyte interface (SEI) with metallic lithium anode. The Li2OHCl solid electrolyte can be readily achieved through simple mixing of air-stable LiOH and LiCl precursors with a mild processing temperature under 400 °C. Additionally, we show that continuous, dense Li2OHCl membranes can be fabricated at temperatures less than 400 °C, standing in great contrast to current processing temperatures of over 1600 °C for most oxide-based solid electrolytes. The ionic conductivity and Arrhenius activation energy were explored for the LiOH-LiCl system of crystalline solidmore » electrolytes where Li2OHCl with increased crystal defects was found to have the highest ionic conductivity and reasonable Arrhenius activation energy. The Li2OHCl solid electrolyte displays stability against metallic lithium, even in extreme conditions past the melting point of lithium metal. Furthermore, to understand this excellent stability, we show that SEI formation is critical in stabilizing the interface between metallic lithium and the Li2OHCl solid electrolyte.« less

  18. Direct Electrolytic Reduction of Solid Ta2O5 to Ta with SOM Process

    NASA Astrophysics Data System (ADS)

    Chen, Chaoyi; Yang, Xiaqiong; Li, Junqi; Lu, Xionggang; Yang, Shufeng

    2016-06-01

    A process that uses the solid-oxide-oxygen-ion conducting membrane has been investigated to produce tantalum directly from solid Ta2O5 in molten CaCl2 or a molten mixture of 55.5MgF2-44.5CaF2 (in wt pct). The sintered porous Ta2O5 pellet was employed as the cathode, while the liquid copper alloy, saturated with graphite powder and encased in a one-end-closed yttria-stabilized-zirconia (YSZ) tube, acted as the anode. The electrolysis potential in this method is higher than that of the Fray-Farthing-Chen Cambridge process because the YSZ membrane tube blocks the melts to electrolyze, and only Ta2O5 is will be electrolyzed. The microstructures of reduced pellets and a cyclic voltammogram of solid Ta2O5 in molten CaCl2 were analyzed. In addition, the influence of particle size and porosity of the cathode pellets on metal-oxide-electrolyte, three-phase interlines was also discussed. The results demonstrate that the sintering temperature of cathode pellets and electrolytic temperature play important roles in the electrochemical process. Furthermore, this process can be used to produce Ta metal efficiently without the expensive cost of pre-electrolysis and generation of harmful by-products.

  19. Dissolution of Neptunium and Plutonium Oxides Using a Catalyzed Electrolytic Process

    SciTech Connect

    Hylton, TD

    2004-10-25

    This report discusses the scoping study performed to evaluate the use of a catalyzed electrolytic process for dissolving {sup 237}Np oxide targets that had been irradiated to produce {sup 238}Pu oxide. Historically, these compounds have been difficult to dissolve, and complete dissolution was obtained only by adding hydrofluoric acid to the nitric acid solvent. The presence of fluoride in the mixture is undesired because the fluoride ions are corrosive to tank and piping systems and the fluoride ions cause interferences in the spectrophotometric analyses. The goal is to find a dissolution method that will eliminate these issues and that can be incorporated into a processing system to support the domestic production and purification of {sup 238}Pu. This study evaluated the potential of cerium(IV) ions, a strong oxidant, to attack and dissolve the oxide compounds. In the dissolution process, the cerium(IV) ions are reduced to cerium(III) ions, which are not oxidants. Therefore, an electrolytic process was incorporated to continuously convert cerium(III) ions back to cerium(IV) ions so that they can dissolve more of the oxide compounds. This study showed that the neptunium and plutonium oxides were successfully dissolved and that more development work should be performed to optimize the procedure.

  20. Longwy: Higher Education and Health Mobilised in the Process of Regeneration

    ERIC Educational Resources Information Center

    Hardouin, Magali; le Goff, Erwan

    2013-01-01

    For almost a century, Longwy has been one of the most important industrial areas of France, contributing the majority of the national production of cast iron and steel. The objective of this paper is to analyse how higher education, then health and well-being were mobilised in the process of regeneration of Longwy, which had been very harshly…

  1. Cryotherapy Reduces Inflammatory Response Without Altering Muscle Regeneration Process and Extracellular Matrix Remodeling of Rat Muscle

    PubMed Central

    Vieira Ramos, Gracielle; Pinheiro, Clara Maria; Messa, Sabrina Peviani; Delfino, Gabriel Borges; Marqueti, Rita de Cássia; Salvini, Tania de Fátima; Durigan, Joao Luiz Quagliotti

    2016-01-01

    The application of cryotherapy is widely used in sports medicine today. Cooling could minimize secondary hypoxic injury through the reduction of cellular metabolism and injury area. Conflicting results have also suggested cryotherapy could delay and impair the regeneration process. There are no definitive findings about the effects of cryotherapy on the process of muscle regeneration. The aim of the present study was to evaluate the effects of a clinical-like cryotherapy on inflammation, regeneration and extracellular matrix (ECM) remodeling on the Tibialis anterior (TA) muscle of rats 3, 7 and 14 days post-injury. It was observed that the intermittent application of cryotherapy (three 30-minute sessions, every 2 h) in the first 48 h post-injury decreased inflammatory processes (mRNA levels of TNF-α, NF-κB, TGF-β and MMP-9 and macrophage percentage). Cryotherapy did not alter regeneration markers such as injury area, desmin and Myod expression. Despite regulating Collagen I and III and their growth factors, cryotherapy did not alter collagen deposition. In summary, clinical-like cryotherapy reduces the inflammatory process through the decrease of macrophage infiltration and the accumulation of the inflammatory key markers without influencing muscle injury area and ECM remodeling. PMID:26725948

  2. Cryotherapy Reduces Inflammatory Response Without Altering Muscle Regeneration Process and Extracellular Matrix Remodeling of Rat Muscle.

    PubMed

    Vieira Ramos, Gracielle; Pinheiro, Clara Maria; Messa, Sabrina Peviani; Delfino, Gabriel Borges; Marqueti, Rita de Cássia; Salvini, Tania de Fátima; Durigan, Joao Luiz Quagliotti

    2016-01-04

    The application of cryotherapy is widely used in sports medicine today. Cooling could minimize secondary hypoxic injury through the reduction of cellular metabolism and injury area. Conflicting results have also suggested cryotherapy could delay and impair the regeneration process. There are no definitive findings about the effects of cryotherapy on the process of muscle regeneration. The aim of the present study was to evaluate the effects of a clinical-like cryotherapy on inflammation, regeneration and extracellular matrix (ECM) remodeling on the Tibialis anterior (TA) muscle of rats 3, 7 and 14 days post-injury. It was observed that the intermittent application of cryotherapy (three 30-minute sessions, every 2 h) in the first 48 h post-injury decreased inflammatory processes (mRNA levels of TNF-α, NF-κB, TGF-β and MMP-9 and macrophage percentage). Cryotherapy did not alter regeneration markers such as injury area, desmin and Myod expression. Despite regulating Collagen I and III and their growth factors, cryotherapy did not alter collagen deposition. In summary, clinical-like cryotherapy reduces the inflammatory process through the decrease of macrophage infiltration and the accumulation of the inflammatory key markers without influencing muscle injury area and ECM remodeling.

  3. Stable dye-sensitized solar cells based on a gel electrolyte with ethyl cellulose as the gelator

    NASA Astrophysics Data System (ADS)

    Vasei, Maryam; Tajabadi, Fariba; Jabbari, Ali; Taghavinia, Nima

    2015-09-01

    A simple gelating process is developed for the conventional acetonitrile-based electrolyte of dye solar cells, based on ethyl cellulose as the gelator. The electrolyte becomes quasi-solid-state upon addition of an ethanolic solution of ethyl cellulose to the conventional acetonitrile-based liquid electrolyte. The photovoltaic conversion efficiency with the new gel electrolyte is only slightly lower than with the liquid electrolyte, e.g., 6.5 % for liquid electrolyte versus 5.9 % for gel electrolyte with 5.8 wt% added ethyl cellulose. Electrolyte gelation has small effect on the ionic diffusion coefficient of iodide, and the devices are remarkably stable for at least 550 h under irradiation at 55 °C.

  4. Integrated Ion Exchange Regeneration Process for Drinking Water

    DTIC Science & Technology

    2010-04-01

    IX Unit Process 87 5.7.1.16 Total Arsenic – IX Unit Process 87 5.7.1.17 Gross Alpha – IX Unit Process 87 5.7.1.18 Radon – IX Unit Process 88...and from source to source Radon SM7500-Rn or EPA 913.0 12 months of operation, 1 sample per month, 2 locations for IE adsorption system; plus 4...materials, such as rocks, minerals, soils , and water, whose radionuclide concentrations or potential for exposure to humans or the environment is enhanced

  5. Structural and ionic conductivity studies of electrospun polymer blend P(VdF-co-HFP)/PMMA electrolyte membrane for lithium battery application

    SciTech Connect

    Padmaraj, O.; Satyanarayana, N.; Venkateswarlu, M.

    2015-06-24

    A novel fibrous polymer blend [(100-x) % P(VdF-co-HFP)/x % PMMA, x = 10, 20, 30, 40, 50] electrolyte membranes were prepared by electrospinning technique. Structural, thermal and surface morphology of all the compositions of electrospun polymer blend membranes were studied by using XRD, DSC & SEM. The newly developed five different compositions of polymer blend fibrous electrolyte membranes were obtained by soaking in an electrolyte solution contains 1M LiPF{sub 6} in EC: DEC (1:1,v/v). The wet-ability and conductivity of all the compositions of polymer blend electrolyte membranes are evaluated through electrolyte uptake and impedance measurements. The polymer blend [90% P(VdF-co-HFP)/10% PMMA] electrolyte membrane showed good wet-ability and high conductivity (1.788 × 10{sup −3} Scm{sup −1}) at room temperature.

  6. Electrolytic process to produce sodium hypochlorite using sodium ion conductive ceramic membranes

    DOEpatents

    Balagopal, Shekar; Malhotra, Vinod; Pendleton, Justin; Reid, Kathy Jo

    2012-09-18

    An electrochemical process for the production of sodium hypochlorite is disclosed. The process may potentially be used to produce sodium hypochlorite from seawater or low purity un-softened or NaCl-based salt solutions. The process utilizes a sodium ion conductive ceramic membrane, such as membranes based on NASICON-type materials, in an electrolytic cell. In the process, water is reduced at a cathode to form hydroxyl ions and hydrogen gas. Chloride ions from a sodium chloride solution are oxidized in the anolyte compartment to produce chlorine gas which reacts with water to produce hypochlorous and hydrochloric acid. Sodium ions are transported from the anolyte compartment to the catholyte compartment across the sodium ion conductive ceramic membrane. Sodium hydroxide is transported from the catholyte compartment to the anolyte compartment to produce sodium hypochlorite within the anolyte compartment.

  7. Solid electrolyte cell

    NASA Technical Reports Server (NTRS)

    Richter, R. (Inventor)

    1982-01-01

    A solid electrolyte cell including a body of solid ionized gas-conductive electrolyte having mutually spaced surfaces and on which is deposited a multiplicity of mutually spaced electrodes is described. Strips and of bare substances are interposed between electrodes, so that currents of ionic gas may be established between the electrodes via the bare strips, whereby electrical resistance for the cells is lowered and the gas conductivity is enhanced.

  8. An Ionic Liquid Reaction and Separation Process for Production of Hydroxymethylfurfural from Sugars

    SciTech Connect

    Liu, Wei; Zheng, Feng; Li, Joanne; Cooper, Alan R.

    2014-01-01

    There has been world-wide interest to making plastics out of renewable biomass feedstock for recent years. Hydroxymethylfurfural (HMF) is viewed as an attractive alternate to terephthalic acid (TPA) for production of polyesters (PET) and polyamides. Conversion of sugars into HMF has been studied in numerous publications. In this work, a complete ionic liquid reaction and separation process is presented for nearly stoichiometric conversion of fructose into HMF. Different adsorbent materials are evaluated and silicalite material is demonstrated effective for isolation of 99% pure HMF from actual ionic liquid reaction mixtures and for recovery of the un-converted sugars and reaction intermediate along with the ionic liquid. Membrane-coated silicalite particles are prepared and studied for a practical adsorption process operated at low pressure drops but with separation performances comparable or better than the powder material. Complete conversion of fresh fructose feed into HMF in the recycled ionic liquid is shown under suitable reaction conditions. Stability of HMF product is characterized. A simplified process flow diagram is proposed based on these research results, and the key equipment such as reactor and adsorbent bed is sized for a plant of 200,000 ton/year of fructose processing capacity. The proposed HMF production process is much simpler than the current paraxylene (PX) manufacturing process from petroleum oil, which suggests substantial reduction to the capital cost and energy consumption be possible. At the equivalent value to PX on the molar basis, there can be a large gross margin for HMF production from fructose and/or sugars.

  9. Ion-Exchanged Waveguides for Signal Processing Applications - A Novel Electrolytic Process.

    DTIC Science & Technology

    1987-03-07

    1986 . 3] R. K. Lagu and V. Ramaswamy, "Fabrication of Single Mode Glass Waveguide by Electrolytic Release of Silver Ions," Appl. Phys. Lett., 45, pp...Quantum Electron., QE-22, pp. 883-891, 1986 . 7 [111] P. Chludzinski, R. V. Ramaswamy, and T. J. Anderson, "Ion-Fxchange Between Sode-Lime Silicate Glass and...Parameter Relationships for the Design of Planar, Silver Ion-Exchanged Glass Waveguide," IEEE J. Lightwave Tech., LT-4, pp. 176-131, 1986 . [20] R. K. Lagu

  10. The Na[FSA]-[C2C1im][FSA] (C2C1im+:1-ethyl-3-methylimidazolium and FSA-:bis(fluorosulfonyl)amide) ionic liquid electrolytes for sodium secondary batteries

    NASA Astrophysics Data System (ADS)

    Matsumoto, Kazuhiko; Hosokawa, Takafumi; Nohira, Toshiyuki; Hagiwara, Rika; Fukunaga, Atsushi; Numata, Koma; Itani, Eiko; Sakai, Shoichiro; Nitta, Koji; Inazawa, Shinji

    2014-11-01

    Physical and electrochemical properties of the Na[FSA]-[C2C1im][FSA] (C2C1im+:1-ethyl-3-methylimidazolium and FSA-:bis(fluorosulfonyl)amide) ionic liquids have been investigated in view of their application as electrolytes for sodium secondary batteries operating in a wide temperature range. The Na[FSA]-[C2C1im][FSA] ionic liquids in the range of 0.0 ≤ x(Na[FSA]) ≤ 0.5 are in the liquid state at room temperature, where x(Na[FSA]) is the mole fraction of Na[FSA]. In the case of x(Na[FSA]) = 0.3, the ionic conductivity, viscosity, and electrochemical window at 298 K are 5.4 mS cm-1, 78 mPa s, and 5.1 V, respectively. Sodium metal deposition/dissolution test in the ionic liquid at x(Na[FSA]) = 0.3 resulted in average cycle efficiencies of 69% and 96% at 298 K and 363 K, respectively, at a current density of 1.0 mA cm-2.

  11. Effect of salts on the solubility of ionic liquids in water: experimental and electrolyte Perturbed-Chain Statistical Associating Fluid Theory†

    PubMed Central

    Mohammad, Sultan; Schleinitz, Miko; Coutinhoa, João A. P.; Freire, Mara G.

    2016-01-01

    Due to scarce available experimental data, as well as due to the absence of predictive models, the influence of salts on the solubility of ionic liquids (ILs) in water is still poorly understood. To this end, this work addresses the solubility of the IL 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([C4C1im][NTf2]), at 298.15 K and 0.1 MPa, in aqueous salt solutions (from 0.1 to 1.5 mol kg−1). At salt molalities higher than 0.2 mol kg−1, all salts caused salting-out of [C4C1im][NTf2] from aqueous solution with their strength decreasing in the following order: Al2(SO4)3 > ZnSO4 > K3C6H5O7 > KNaC4H4O6 > K3PO4 > Mg(CH3CO2)2 > K2HPO4 > MgSO4 > KH2PO4 > KCH3CO2. Some of these salts lead however to the salting-in of [C4C1im][NTf2] in aqueous medium at salt molalities lower than 0.20 mol kg−1. To attempt the development of a model able to describe the salt effects, comprising both the salting-in and salting-out phenomena observed, the electrolyte Perturbed-Chain Statistical Associating Fluid Theory (ePC-SAFT) was applied using ion-specific parameters. The gathered experimental data was modelled using ePC-SAFT parameters complemented by fitting a single binary parameter between K+ and the IL-ions to the IL solubility in K3PO4 aqueous solutions. Based on this approach, the description of anion-specific salting-out effects of the remaining potassium salts was found to be in good agreement with experimental data. Remarkably, ePC-SAFT is even able to predict the salting-in effect induced by K2HPO4, based on the single K+/IL-ions binary parameter which was fitted to an exclusively salting-out effect promoted by K3PO4. Finally, ePC-SAFT was applied to predict the influence of other sodium salts on the [C4C1im][NTf2] solubility in water, with experimental data taken from literature, leading to an excellent description of the liquid–liquid phase behaviour. PMID:26575280

  12. Effect of salts on the solubility of ionic liquids in water: experimental and electrolyte Perturbed-Chain Statistical Associating Fluid Theory.

    PubMed

    Neves, Catarina M S S; Held, Christoph; Mohammad, Sultan; Schleinitz, Miko; Coutinho, João A P; Freire, Mara G

    2015-12-21

    Due to scarce available experimental data, as well as due to the absence of predictive models, the influence of salts on the solubility of ionic liquids (ILs) in water is still poorly understood. To this end, this work addresses the solubility of the IL 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([C4C1im][NTf2]), at 298.15 K and 0.1 MPa, in aqueous salt solutions (from 0.1 to 1.5 mol kg(-1)). At salt molalities higher than 0.2 mol kg(-1), all salts caused salting-out of [C4C1im][NTf2] from aqueous solution with their strength decreasing in the following order: Al2(SO4)3 > ZnSO4 > K3C6H5O7 > KNaC4H4O6 > K3PO4 > Mg(CH3CO2)2 > K2HPO4 > MgSO4 > KH2PO4 > KCH3CO2. Some of these salts lead however to the salting-in of [C4C1im][NTf2] in aqueous medium at salt molalities lower than 0.2 mol kg(-1). To attempt the development of a model able to describe the salt effects, comprising both the salting-in and salting-out phenomena observed, the electrolyte Perturbed-Chain Statistical Associating Fluid Theory (ePC-SAFT) was applied using ion-specific parameters. The gathered experimental data was modelled using ePC-SAFT parameters complemented by fitting a single binary parameter between K(+) and the IL-ions to the IL solubility in K3PO4 aqueous solutions. Based on this approach, the description of anion-specific salting-out effects of the remaining potassium salts was found to be in good agreement with experimental data. Remarkably, ePC-SAFT is even able to predict the salting-in effect induced by K2HPO4, based on the single K(+)/IL-ions binary parameter which was fitted to an exclusively salting-out effect promoted by K3PO4. Finally, ePC-SAFT was applied to predict the influence of other sodium salts on the [C4C1im][NTf2] solubility in water, with experimental data taken from literature, leading to an excellent description of the liquid-liquid phase behaviour.

  13. Dissolution and fractionation of nut shells in ionic liquids.

    PubMed

    Carneiro, Aristides P; Rodríguez, Oscar; Macedo, Eugénia A

    2017-03-01

    The aim of this work was to study the dissolution of raw peanut and chestnut shells in ionic liquids. Dissolution of raw biomass up to 7wt% was achieved under optimized operatory conditions. Quantification of polysaccharides dissolved through quantitative (13)Cq NMR revealed extractions of the cellulosic material to ionic liquids as high as 87%. Regeneration experiments using an antisolvent mixture allowed to recover the cellulosic material and the ionic liquid. The overall mass balance presented very low loss rates (<8%), recoveries of 75% and 95% of cellulosic material from peanut and chestnut shells, respectively, and the recovery of more than 95% of the ionic liquid in both cases. These results show the high potential of using nut shells and ionic liquids for biorefining purposes. Moreover, high recovery of ionic liquids favors the process from an economical point of view.

  14. Electrolytic recovery of reactor metal fuel

    DOEpatents

    Miller, William E.; Tomczuk, Zygmunt

    1994-01-01

    A new electrolytic process and apparatus are provided using sodium, cerium or a similar metal in alloy or within a sodium beta or beta"-alumina sodium ion conductor to electrolytically displace each of the spent fuel metals except for cesium and strontium on a selective basis from the electrolyte to an inert metal cathode. Each of the metals can be deposited separately. An electrolytic transfer of spent fuel into the electrolyte includes a sodium or cerium salt in the electrolyte with sodium or cerium alloy being deposited on the cathode during the transfer of the metals from the spent fuel. The cathode with the deposit of sodium or cerium alloy is then chanted to an anode and the reverse transfer is carried out on a selective basis with each metal being deposited separately at the cathode. The result is that the sodium or cerium needed for the process is regenerated in the first step and no additional source of these reactants is required.

  15. Electrolytic recovery of reactor metal fuel

    DOEpatents

    Miller, W.E.; Tomczuk, Z.

    1994-09-20

    A new electrolytic process and apparatus are provided using sodium, cerium or a similar metal in alloy or within a sodium beta or beta[double prime]-alumina sodium ion conductor to electrolytically displace each of the spent fuel metals except for cesium and strontium on a selective basis from the electrolyte to an inert metal cathode. Each of the metals can be deposited separately. An electrolytic transfer of spent fuel into the electrolyte includes a sodium or cerium salt in the electrolyte with sodium or cerium alloy being deposited on the cathode during the transfer of the metals from the spent fuel. The cathode with the deposit of sodium or cerium alloy is then shunted to an anode and the reverse transfer is carried out on a selective basis with each metal being deposited separately at the cathode. The result is that the sodium or cerium needed for the process is regenerated in the first step and no additional source of these reactants is required. 2 figs.

  16. Electrolytic recovery of reactor metal fuel

    DOEpatents

    Miller, W.E.; Tomczuk, Z.

    1993-02-03

    This invention is comprised of a new electrolytic process and apparatus using sodium, cerium or a similar metal in an alloy or within a sodium beta or beta-alumina sodium ion conductor to electrolytically displace each of the spent fuel metals except for Cesium and strontium on a selective basis from the electrolyte to an inert metal cathode. Each of the metals can be deposited separately. An electrolytic transfer of spent fuel into the electrolyte includes a sodium or cerium salt in the electrolyte with sodium or cerium alloy being deposited on the cathode during the transfer of the metals from the spent fuel. The cathode with the deposit of sodium or cerium alloy is then changed to an anode and the reverse transfer is carried out on a selective basis with each metal being deposited separately at the cathode. The result is that the sodium or cerium needed for the process is regenerated in the first step and no additional source of these reactants is required.

  17. Modifying Mechanical, Optical Properties and Thermal Processability of Iridescent Cellulose Nanocrystal Films Using Ionic Liquid.

    PubMed

    Liu, Ping; Guo, Xin; Nan, Fuchun; Duan, Yongxin; Zhang, Jianming

    2017-01-25

    Iridescent films formed from the self-assembly of cellulose nanocrystals (CNCs) are brittle and difficult to handle or integrate within an industrial process. Here we present a simple approach to prepare iridescent CNC films with tunable pliability and coloration through the addition of ionic liquids (ILs) of 1-allyl-3-methylimidazolium chloride (AmimCl) as plasticizers. By using the undried CNC film as a filter membrane and ILs solution as a leaching liquid, it was found that the filtration process made ILs uniformly interpenetrate into CNC film due to the strong ionic interaction between CNC and AmimCl. Unexpectedly, the filtration process also gave rise to partial desulfurization of CNC film, which is conducive to the improvement of thermal stability. Benefiting from the improved thermal stability and the dissolving capacity of AmimCl for cellulose at high temperature, the incorporated ILs enable the cholesteric CNC film to be further toughened via a hot-pressing treatment. This study demonstrates that ionic liquids have great potential to modify the mechanical, optical properties as well as the thermal stability of iridescent CNC films.

  18. Process for CO2 Capture Using Ionic Liquid That Exhibits Phase Change

    SciTech Connect

    Eisinger, RS; Keller, GE

    2014-11-01

    A novel process for capturing carbon dioxide from the flue gas of a coal-fired power plant has been shown to reduce parasitic power consumption substantially. The process employs an ionic liquid created at the University of Notre Dame that has a high capacity for absorbing CO2 by chemical reaction. A distinguishing property of this ionic liquid is that it changes phase from solid to liquid upon reaction with CO2. The process uses heat generated by this phase transition to lower parasitic power consumption. The driving force for CO2 separation is a combination of temperature and pressure differences; the process could even work without the addition of heat. A realistic process was created to capture CO2 efficiently. Computer simulation of the process enabled calculation of viable process conditions and power usage. The main concepts of the process were shown to work using a lab-scale apparatus. Parasitic power consumes 23% of net power generation, 55% lower than that of the monoethanolamine (MEA) process. However, capital cost is higher. The cost of electricity (COE) is 28% lower than that of the MEA process.

  19. Down Select Report of Chemical Hydrogen Storage Materials, Catalysts, and Spent Fuel Regeneration Processes

    SciTech Connect

    Ott, Kevin; Linehan, Sue; Lipiecki, Frank; Aardahl, Christopher L.

    2008-08-24

    The DOE Hydrogen Storage Program is focused on identifying and developing viable hydrogen storage systems for onboard vehicular applications. The program funds exploratory research directed at identifying new materials and concepts for storage of hydrogen having high gravimetric and volumetric capacities that have the potential to meet long term technical targets for onboard storage. Approaches currently being examined are reversible metal hydride storage materials, reversible hydrogen sorption systems, and chemical hydrogen storage systems. The latter approach concerns materials that release hydrogen in endothermic or exothermic chemical bond-breaking processes. To regenerate the spent fuels arising from hydrogen release from such materials, chemical processes must be employed. These chemical regeneration processes are envisioned to occur offboard the vehicle.

  20. Removal of contaminant gases from an electrolytic urine pretreatment process. [in spacecraft life support systems

    NASA Technical Reports Server (NTRS)

    Colombo, G. V.; Putnam, D. F.

    1977-01-01

    The effluent gas stream from an electrolytic urine pretreatment process was analyzed by gas chromatography-mass spectroscopy and wet chemical methods to determine its composition. The major constituents were identified as: hydrogen, carbon dioxide, oxygen, nitrogen, water vapor, and chlorine. The trace impurities were chlorinated light hydrocarbons, and a number of other organic impurities in the low ppm range. Several methods of removing all of the undesirable gases to levels acceptable for return to a space cabin atmosphere were investigated experimentally. A subsystem concept comprised of the following sequential unit processes and operations was successfully demonstrated: (1) raw urine scrubbing, (2) silica gel sorption, (3) dilution with cabin air, and (4) catalytic oxidation.

  1. Effects of ultrasound on the evolution of plasma electrolytic oxidation process on 6061Al alloy.

    PubMed

    Shen, Dejiu; He, Donglei; Liu, Fangfei; Guo, Changhong; Cai, Jingrui; Li, Guolong; Ma, Haojie

    2014-04-01

    The plasma electrolytic oxidation (PEO) process of 6061Al alloy was carried out under the conditions with and without the assistance of ultrasound, respectively. The effects of ultrasound on the evolution of voltage, micro-discharge, morphology and composition of PEO coatings were investigated. The results show that ultrasound can greatly decrease the dielectric breakdown voltage of the coatings, increase the number of micro-discharges while decrease their average size, promote the evolution of micro-discharges, decrease the number and the average size of residual discharge pores in the coatings after 30min of the process, promote the homogeneous distribution of elements and the formation of α-Al2O3 and 3Al2O3⋅2SiO2 in the coatings.

  2. Forming solid electrolyte interphase in situ in an ionic conducting Li1.5Al0.5Ge1.5(PO4)3-polypropylene (PP) based separator for Li-ion batteries

    NASA Astrophysics Data System (ADS)

    Jiao-Yang, Wu; Shi-Gang, Ling; Qi, Yang; Hong, Li; Xiao-Xiong, Xu; Li-Quan, Chen

    2016-07-01

    A new concept of forming solid electrolyte interphases (SEI) in situ in an ionic conducting Li1.5Al0.5Ge1.5(PO4)3-polypropylene (LAGP-PP) based separator during charging and discharging is proposed and demonstrated. This unique structure shows a high ionic conductivity, low interface resistance with electrode, and can suppress the growth of lithium dendrite. The features of forming the SEI in situ are investigated by scanning electron microscopy (SEM) and x-ray photoelectron spectroscopy (XPS). The results confirm that SEI films mainly consist of lithium fluoride and carbonates with various alkyl contents. The cell assembled by using the LAGP-coated separator demonstrates a good cycling performance even at high charging rates, and the lithium dendrites were not observed on the lithium metal electrode. Therefore, the SEI-LAGP-PP separator can be used as a promising flexible solid electrolyte for solid state lithium batteries. Project supported by the Beijing Science and Technology Project, China (Grant No. Z13111000340000), the National Basic Research Program of China (Grant No. 2012CB932900), and the National Natural Science Foundation of China (Grant Nos. 51325206 and 51421002).

  3. A Direct Sulfation Process of a Marine Polysaccharide in Ionic Liquid.

    PubMed

    Chopin, Nathalie; Sinquin, Corinne; Ratiskol, Jacqueline; Zykwinska, Agata; Weiss, Pierre; Cérantola, Stéphane; Le Bideau, Jean; Colliec-Jouault, Sylvia

    2015-01-01

    GY785 is an exopolysaccharide produced by a mesophilic bacterial strain Alteromonas infernus discovered in the deep-sea hydrothermal vents. GY785 highly sulfated derivative (GY785 DRS) was previously demonstrated to be a promising molecule driving the efficient mesenchymal stem cell chondrogenesis for cartilage repair. This glycosaminoglycan- (GAG-) like compound was modified in a classical solvent (N,N'-dimethylformamide). However, the use of classical solvents limits the polysaccharide solubility and causes the backbone degradation. In the present study, a one-step efficient sulfation process devoid of side effects (e.g., polysaccharide depolymerization and/or degradation) was developed to produce GAG-like derivatives. The sulfation of GY785 derivative (GY785 DR) was carried out using ionic liquid as a reaction medium. The successful sulfation of this anionic and highly branched heteropolysaccharide performed in ionic liquid would facilitate the production of new molecules of high specificity for biological targets such as tissue engineering or regenerative medicine.

  4. Surface modification by electrolytic plasma processing for high Nb-TiAl alloys

    NASA Astrophysics Data System (ADS)

    Gui, Wanyuan; Hao, Guojian; Liang, Yongfeng; Li, Feng; Liu, Xiao; Lin, Junpin

    2016-12-01

    Metal surface modification by electrolytic plasma processing (EPP) is an innovative treatment widely commonly applied to material processing and pretreatment process of coating and galvanization. EPP involves complex processes and a great deal of parameters, such as preset voltage, current, solution temperature and processing time. Several characterization methods are presented in this paper for evaluating the micro-structure surfaces of Ti45Al8Nb alloys: SEM, EDS, XRD and 3D topography. The results showed that the oxide scale and other contaminants on the surface of Ti45Al8Nb alloys can be effectively removed via EPP. The typical micro-crater structure of the surface of Ti45Al8Nb alloys were observed by 3D topography after EPP to find that the mean diameter of the surface structure and roughness value can be effectively controlled by altering the processing parameters. The mechanical properties of the surface according to nanomechanical probe testing exhibited slight decrease in microhardness and elastic modulus after EPP, but a dramatic increase in surface roughness, which is beneficial for further processing or coating.

  5. Ion distributions in electrolyte confined by multiple dielectric interfaces

    NASA Astrophysics Data System (ADS)

    Jing, Yufei; Zwanikken, Jos W.; Jadhao, Vikram; de La Cruz, Monica

    2014-03-01

    The distribution of ions at dielectric interfaces between liquids characterized by different dielectric permittivities is crucial to nanoscale assembly processes in many biological and synthetic materials such as cell membranes, colloids and oil-water emulsions. The knowledge of ionic structure of these systems is also exploited in energy storage devices such as double-layer super-capacitors. The presence of multiple dielectric interfaces often complicates computing the desired ionic distributions via simulations or theory. Here, we use coarse-grained models to compute the ionic distributions in a system of electrolyte confined by two planar dielectric interfaces using Car-Parrinello molecular dynamics simulations and liquid state theory. We compute the density profiles for various electrolyte concentrations, stoichiometric ratios and dielectric contrasts. The explanations for the trends in these profiles and discuss their effects on the behavior of the confined charged fluid are also presented.

  6. Capillary electrophoresis with contactless conductivity detection for the quantification of fluoride in lithium ion battery electrolytes and in ionic liquids-A comparison to the results gained with a fluoride ion-selective electrode.

    PubMed

    Pyschik, Marcelina; Klein-Hitpaß, Marcel; Girod, Sabrina; Winter, Martin; Nowak, Sascha

    2017-02-01

    In this study, an optimized method using capillary electrophoresis (CE) with a direct contactless conductivity detector (C(4) D) for a new application field is presented for the quantification of fluoride in common used lithium ion battery (LIB) electrolyte using LiPF6 in organic carbonate solvents and in ionic liquids (ILs) after contacted to Li metal. The method development for finding the right buffer and the suitable CE conditions for the quantification of fluoride was investigated. The results of the concentration of fluoride in different LIB electrolyte samples were compared to the results from the ion-selective electrode (ISE). The relative standard deviations (RSDs) and recovery rates for fluoride were obtained with a very high accuracy in both methods. The results of the fluoride concentration in the LIB electrolytes were in very good agreement for both methods. In addition, the limit of detection (LOD) and limit of quantification (LOQ) values were determined for the CE method. The CE method has been applied also for the quantification of fluoride in ILs. In the fresh IL sample, the concentration of fluoride was under the LOD. Another sample of the IL mixed with Li metal has been investigated as well. It was possible to quantify the fluoride concentration in this sample.

  7. Nitrogen Chemistry and Coke Transformation of FCC Coked Catalyst during the Regeneration Process

    PubMed Central

    Shi, Junjun; Guan, Jianyu; Guo, Dawei; Zhang, Jiushun; France, Liam John; Wang, Lefu; Li, Xuehui

    2016-01-01

    Regeneration of the coked catalyst is an important process of fluid catalytic cracking (FCC) in petroleum refining, however, this process will emit environmentally harmful gases such as nitrogen and carbon oxides. Transformation of N and C containing compounds in industrial FCC coke under thermal decomposition was investigated via TPD and TPO to examine the evolved gaseous species and TGA, NMR and XPS to analyse the residual coke fraction. Two distinct regions of gas evolution are observed during TPD for the first time, and they arise from decomposition of aliphatic carbons and aromatic carbons. Three types of N species, pyrrolic N, pyridinic N and quaternary N are identified in the FCC coke, the former one is unstable and tends to be decomposed into pyridinic and quaternary N. Mechanisms of NO, CO and CO2 evolution during TPD are proposed and lattice oxygen is suggested to be an important oxygen resource. Regeneration process indicates that coke-C tends to preferentially oxidise compared with coke-N. Hence, new technology for promoting nitrogen-containing compounds conversion will benefit the in-situ reduction of NO by CO during FCC regeneration. PMID:27270486

  8. Nitrogen Chemistry and Coke Transformation of FCC Coked Catalyst during the Regeneration Process

    NASA Astrophysics Data System (ADS)

    Shi, Junjun; Guan, Jianyu; Guo, Dawei; Zhang, Jiushun; France, Liam John; Wang, Lefu; Li, Xuehui

    2016-06-01

    Regeneration of the coked catalyst is an important process of fluid catalytic cracking (FCC) in petroleum refining, however, this process will emit environmentally harmful gases such as nitrogen and carbon oxides. Transformation of N and C containing compounds in industrial FCC coke under thermal decomposition was investigated via TPD and TPO to examine the evolved gaseous species and TGA, NMR and XPS to analyse the residual coke fraction. Two distinct regions of gas evolution are observed during TPD for the first time, and they arise from decomposition of aliphatic carbons and aromatic carbons. Three types of N species, pyrrolic N, pyridinic N and quaternary N are identified in the FCC coke, the former one is unstable and tends to be decomposed into pyridinic and quaternary N. Mechanisms of NO, CO and CO2 evolution during TPD are proposed and lattice oxygen is suggested to be an important oxygen resource. Regeneration process indicates that coke-C tends to preferentially oxidise compared with coke-N. Hence, new technology for promoting nitrogen-containing compounds conversion will benefit the in-situ reduction of NO by CO during FCC regeneration.

  9. Epigenetics and Shared Molecular Processes in the Regeneration of Complex Structures

    PubMed Central

    Rouhana, Labib; Tasaki, Junichi

    2016-01-01

    The ability to regenerate complex structures is broadly represented in both plant and animal kingdoms. Although regenerative abilities vary significantly amongst metazoans, cumulative studies have identified cellular events that are broadly observed during regenerative events. For example, structural damage is recognized and wound healing initiated upon injury, which is followed by programmed cell death in the vicinity of damaged tissue and a burst in proliferation of progenitor cells. Sustained proliferation and localization of progenitor cells to site of injury give rise to an assembly of differentiating cells known as the regeneration blastema, which fosters the development of new tissue. Finally, preexisting tissue rearranges and integrates with newly differentiated cells to restore proportionality and function. While heterogeneity exists in the basic processes displayed during regenerative events in different species—most notably the cellular source contributing to formation of new tissue—activation of conserved molecular pathways is imperative for proper regulation of cells during regeneration. Perhaps the most fundamental of such molecular processes entails chromatin rearrangements, which prime large changes in gene expression required for differentiation and/or dedifferentiation of progenitor cells. This review provides an overview of known contributions to regenerative processes by noncoding RNAs and chromatin-modifying enzymes involved in epigenetic regulation. PMID:26681954

  10. Nitrogen Chemistry and Coke Transformation of FCC Coked Catalyst during the Regeneration Process.

    PubMed

    Shi, Junjun; Guan, Jianyu; Guo, Dawei; Zhang, Jiushun; France, Liam John; Wang, Lefu; Li, Xuehui

    2016-06-08

    Regeneration of the coked catalyst is an important process of fluid catalytic cracking (FCC) in petroleum refining, however, this process will emit environmentally harmful gases such as nitrogen and carbon oxides. Transformation of N and C containing compounds in industrial FCC coke under thermal decomposition was investigated via TPD and TPO to examine the evolved gaseous species and TGA, NMR and XPS to analyse the residual coke fraction. Two distinct regions of gas evolution are observed during TPD for the first time, and they arise from decomposition of aliphatic carbons and aromatic carbons. Three types of N species, pyrrolic N, pyridinic N and quaternary N are identified in the FCC coke, the former one is unstable and tends to be decomposed into pyridinic and quaternary N. Mechanisms of NO, CO and CO2 evolution during TPD are proposed and lattice oxygen is suggested to be an important oxygen resource. Regeneration process indicates that coke-C tends to preferentially oxidise compared with coke-N. Hence, new technology for promoting nitrogen-containing compounds conversion will benefit the in-situ reduction of NO by CO during FCC regeneration.

  11. Ionic current devices-Recent progress in the merging of electronic, microfluidic, and biomimetic structures.

    PubMed

    Koo, Hyung-Jun; Velev, Orlin D

    2013-05-09

    We review the recent progress in the emerging area of devices and circuits operating on the basis of ionic currents. These devices operate at the intersection of electrochemistry, electronics, and microfluidics, and their potential applications are inspired by essential biological processes such as neural transmission. Ionic current rectification has been demonstrated in diode-like devices containing electrolyte solutions, hydrogel, or hydrated nanofilms. More complex functions have been realized in ionic current based transistors, solar cells, and switching memory devices. Microfluidic channels and networks-an intrinsic component of the ionic devices-could play the role of wires and circuits in conventional electronics.

  12. Multiphysics modeling of lithium ion battery capacity fading process with solid-electrolyte interphase growth by elementary reaction kinetics

    NASA Astrophysics Data System (ADS)

    Xie, Yuanyuan; Li, Jianyang; Yuan, Chris

    2014-02-01

    A pseudo two-dimensional mathematical model is developed for a lithium ion battery, integrating the elementary reaction based solid-electrolyte interphase (SEI) growth model with multiple transport processes. The model is validated using the experimental data. Simulation results indicate that the operating temperature has great effect on the SEI layer generation and growth. Under different charging-discharging rates, it is found that high charging-discharging rate can intensify the battery capacity fading process. Different cooling conditions are then applied and show that enhanced surface convective cooling condition can effectively slow down the battery capacity fading. After that, the effect of electrolyte salt concentration and exchange current density are studied. It is found that raising the electrolyte salt concentration can improve the diffusion property of lithium ions, and stabilize the battery performance under lithium ion consumption induced resistance rising. It also suggests that improving exchange current density could greatly decrease the lithium ion battery capacity fading.

  13. Fabrication of hollow mesoporous NiO hexagonal microspheres via hydrothermal process in ionic liquid

    SciTech Connect

    Zhao, Jinbo; Wu, Lili; Zou, Ke

    2011-12-15

    Highlights: Black-Right-Pointing-Pointer Ni(OH){sub 2} precursors were synthesized in ionic liquid and water solution by hydrothermal method. Black-Right-Pointing-Pointer NiO hollow microspheres were prepared by thermal treatment of Ni(OH){sub 2} precursors. Black-Right-Pointing-Pointer NiO hollow microspheres were self-assembled by mesoporous cubic and hexagonal nanocrystals with high specific surface area. Black-Right-Pointing-Pointer The mesoporous structure is stable at 773 K. Black-Right-Pointing-Pointer The ionic liquid absorbed on the O-terminate surface of the crystals to form hydrogen bond and played key roles in determining the final shape of the NiO novel microstructure. -- Abstract: The novel NiO hexagonal hollow microspheres have been successfully prepared by annealing Ni(OH){sub 2}, which was synthesized via an ionic liquid-assisted hydrothermal method. The samples were characterized by X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM), transmission electron microscopy (TEM), N{sub 2} adsorption-desorption and Fourier transform infrared spectrometer (FTIR). The results show that the hollow NiO microstructures are self-organized by mesoporous cubic and hexagonal nanocrystals. The mesoporous structure possessed good thermal stability and high specific surface area (ca. 83 m{sup 2}/g). The ionic liquid 1-butyl-3methylimidazolium tetrafluoroborate ([Bmim][BF{sub 4}]) was found to play a key role in controlling the morphology of NiO microstructures during the hydrothermal process. The special hollow mesoporous architectures will have potential applications in many fields, such as catalysts, absorbents, sensors, drug-delivery carriers, acoustic insulators and supercapacitors.

  14. Influence of binder properties on kinetic and transport processes in polymer electrolyte fuel cell electrodes.

    PubMed

    Sambandam, Satheesh; Ramani, Vijay

    2010-06-21

    The objectives of this study are to estimate the contributions of kinetic, ohmic and mass transport overpotentials to the overall voltage loss in polymer electrolyte membrane fuel cell (PEMFC) electrodes and to relate these overpotentials to electrode binder properties such as ionic conductivity, ion exchange capacity (IEC) and O(2) permeability. The model electrode binders studied were perfluorosulfonic acid ionomers (PFSA; of IECs 1.35 meq g(-1) and 0.95 meq g(-1)), sulfonated poly ether ether ketone (SPEEK; of IECs 1.35, 1.75 and 2.1 meq g(-1)) and sulfonated poly sulfone (SPSU; of IEC 1.5 meq g(-1)). The O(2) permeability of these binders varied from 0.15 x 10(-12) mol cm(-1) s(-1) for SPSU to 6 x 10(-12) mol cm(-1) s(-1) for PFSA IEC 0.95 meq g(-1) at 80 degrees C and 75%RH. The electrodes prepared were characterized by cyclic voltammetry to estimate electrochemically active surface area (ECA) of platinum. Steady state polarization (V-I) experiments were performed with hydrogen as fuel and oxidants including O(2), 21% O(2)/N(2) (air), 21% O(2)/He (Helox) and 4% O(2)/N(2). The V-I data obtained was analyzed to determine the relative contributions of the different sources of polarization in the electrode. Electrodes prepared with PFSA binders had similar ECAs of 28 m(2) g(-1)-Pt, while those prepared using hydrocarbon binders had an ECA of 10 to 14 m(2) g(-1)-Pt at 80 degrees C and 75%RH. The same trend was seen in mass activity. At optimized binder loadings, a semi-quantitative relationship was obtained relating binder O(2) permeability to the mass transport losses within the electrode. Furthermore, a novel semi-quantitative method of plotting helox-air voltage gain against O(2)-air gain was employed to probe the O(2) transport limitations in the electrodes. Based on this analysis, it is suggested that the SPEEK and SPSU bound electrodes suffered from binder phase diffusion limitations in addition to gas phase diffusion limitation, while the PFSA bound

  15. Theoretical study of the acid-base properties of the montmorillonite/electrolyte interface: influence of the surface heterogeneity and ionic strength on the potentiometric titration curves.

    PubMed

    Zarzycki, Piotr; Thomas, Fabien

    2006-10-15

    The parallel shape of the potentiometric titration curves for montmorillonite suspension is explained using the surface complexation model and taking into account the surface heterogeneity. The homogeneous models give accurate predictions only if they assume unphysically large values of the equilibrium constants for the exchange process occurring on the basal plane. However, the assumption that the basal plane is energetically heterogeneous allows to fit the experimental data (reported by Avena and De Pauli [M. Avena, C.P. De Pauli, J. Colloid Interface Sci. 202 (1998) 195-204]) for reasonable values of exchange equilibrium constant equal to 1.26 (suggested by Fletcher and Sposito [P. Fletcher, G. Sposito, Clay Miner. 24 (1989) 375-391]). Moreover, we observed the typical behavior of point of zero net proton charge (pznpc) as a function of logarithm of the electrolyte concentration (log[C]). We showed that the slope of the linear dependence, pznpc=f(log[C]), is proportional to the number of isomorphic substitutions in the crystal phase, which was also observed in the experimental studies.

  16. Voltage charging enhances ionic conductivity in gold nanotube membranes.

    PubMed

    Gao, Peng; Martin, Charles R

    2014-08-26

    Ionically conductive membranes are used in many electrochemical processes and devices, including batteries, fuel cells, and electrolyzers. In all such applications, it is advantageous to use membranes with high ionic conductivity because membrane resistance causes a voltage loss suffered by the cell. We describe here a method for enhancing ionic conductivity in membranes containing small diameter (4 nm) gold nanotubes. This entails making the gold nanotube membrane the working electrode in an electrochemical cell and applying a voltage to the membrane. We show here that voltage charging in this way can increase membrane ionic conductivity by over an order of magnitude. When expressed in terms of the ionic conductivity of the electrolyte, κ, within an individual voltage-charged tube, the most negative applied voltage yielded a κ comparable to that of 1 M aqueous KCl, over 2 orders of magnitude higher than κ of the 0.01 M KCl solution contacting the membrane.

  17. Identification of homeobox genes expressed during the process of rat liver regeneration after partial hapatectomy

    SciTech Connect

    Mizuta, Ikuko; Ogasawara, Naotake; Yoshikawa, Hiroshi; Sakoyama, Yasuhiko

    1996-02-01

    Homeobox (HBox) genes are well-known to be involved in development and differentiation. To ascertain a role of HBox genes in the process of liver regeneration, we identified HBox genes expressed at various times after partial hepatectomy in rats (at 0 hr, 1 hr, 2 days, and 4 days) by using reverse transcription-polymerase chain reaction (RT-PCR), cloning, and sequencing techniques. By the competitive RT-PCR method using generic primers, expression levels of HBox genes in regenerating livers were estimated at as low as only 0.4-2% of that in 14-day embryonic liver; however, we identified multiple HBox genes at different stages. Comparing sets of HBox genes identified at different stages, we could find two candidates of stage specifically expressed HBox genes (one rat caudal-related gene, RCdx-3, stimulated at 1 hr, and one rat Hox gene, RHoxB5, repressed after hepatectomy) and continuous expression of five Hox genes (RHoxAl, A4, A5, B2, and B3) before and after hepatectomy. These HBox genes are considered to correlate with the process of liver regeneration. 36 refs., 6 figs., 2 tabs.

  18. Regeneration of an aqueous solution from an acid gas absorption process by matrix stripping

    DOEpatents

    Rochelle, Gary T.; Oyenekan, Babatunde A.

    2011-03-08

    Carbon dioxide and other acid gases are removed from gaseous streams using aqueous absorption and stripping processes. By replacing the conventional stripper used to regenerate the aqueous solvent and capture the acid gas with a matrix stripping configuration, less energy is consumed. The matrix stripping configuration uses two or more reboiled strippers at different pressures. The rich feed from the absorption equipment is split among the strippers, and partially regenerated solvent from the highest pressure stripper flows to the middle of sequentially lower pressure strippers in a "matrix" pattern. By selecting certain parameters of the matrix stripping configuration such that the total energy required by the strippers to achieve a desired percentage of acid gas removal from the gaseous stream is minimized, further energy savings can be realized.

  19. Electrochemical regeneration of phenol-saturated activated carbon - proposal of a reactor.

    PubMed

    Zanella, Odivan; Bilibio, Denise; Priamo, Wagner Luiz; Tessaro, Isabel Cristina; Féris, Liliana Amaral

    2017-03-01

    An electrochemical process was used to investigate the activated carbon regeneration efficiency (RE) saturated with aromatics. For this purpose, an electrochemical reactor was developed and the operational conditions of this equipment were investigated, which is applied in activated carbon regeneration process. The influence of regeneration parameters such as processing time, the current used, the polarity and the processing fluid (electrolyte) were studied. The performance of electrochemical regeneration was evaluated by adsorption tests, using phenol as adsorbate. The increase in current applied and the process time was found to enhance the RE. Another aspect that indicated a better reactor performance was the type of electrolyte used, showing best results for NaCl. The polarity showed the highest influence on the process, when the cathodic regeneration was more efficient. The electrochemical regeneration process developed in this study presented regeneration capacities greater than 100% when the best process conditions were used, showing that this form of regeneration for activated carbon saturated with aromatics is very promising.

  20. Fact Sheet - Final Air Toxics Rule for Steel Pickling and HCI Process Facilities and Hydrochloric Acid Regeneration Plants

    EPA Pesticide Factsheets

    Fact Sheet summarizing the main points of the national emssions standard for hazaradous air pollutants (NESHAP) for Steel Pickling— HCl Process Facilities and Hydrochloric Acid Regeneration Plants as promulgated on June 22, 1999.

  1. Rat-derived processed nerve allografts support more axon regeneration in rat than human-derived processed nerve xenografts.

    PubMed

    Wood, Matthew D; Kemp, Stephen W P; Liu, Edward H; Szynkaruk, Mark; Gordon, Tessa; Borschel, Gregory H

    2014-04-01

    Processed nerve allografts are increasingly used as "off the shelf" nerve replacements for surgically bridging nerve gaps. Benchmarking the regenerative capacity of a commercially available human-derived nerve or xenograft in a rat nerve injury model would provide a convenient platform for future studies seeking to modify the processed nerve graft. Human and rat processed nerve grafts were used to bridge a 14 mm defect in a Sprague-Dawley rat sciatic nerve. Reversed autografts served as a positive control group. Twelve weeks following surgery, the distal nerve stumps were retrograde labeled and harvested for histology and histomorphometry. The cross-sectional areas of the human- and rat-derived processed nerve grafts were similar. Neuron counts and myelinated axon counts following use of the human-derived processed xenografts were decreased compared with those obtained from both the rat-derived processed nerve allografts and the autografts; the rat-derived processed nerve allografts were statistically equivalent to autografts. Measures of nerve fiber diameter and myelination revealed inferior axon regeneration maturity in both processed nerve grafts compared with autografts. Processed xenografts showed significantly reduced regeneration compared with autografts or processed allografts indicating that cross-species immunological reactions are important considerations in this rat model.

  2. Ionic structure in liquids confined by dielectric interfaces

    NASA Astrophysics Data System (ADS)

    Jing, Yufei; Jadhao, Vikram; Zwanikken, Jos W.; Olvera de la Cruz, Monica

    2015-11-01

    The behavior of ions in liquids confined between macromolecules determines the outcome of many nanoscale assembly processes in synthetic and biological materials such as colloidal dispersions, emulsions, hydrogels, DNA, cell membranes, and proteins. Theoretically, the macromolecule-liquid boundary is often modeled as a dielectric interface and an important quantity of interest is the ionic structure in a liquid confined between two such interfaces. The knowledge gleaned from the study of ionic structure in such models can be useful in several industrial applications, such as in the design of double-layer supercapacitors for energy storage and in the extraction of metal ions from wastewater. In this article, we compute the ionic structure in a model system of electrolyte confined by two planar dielectric interfaces using molecular dynamics simulations and liquid state theory. We explore the effects of high electrolyte concentrations, multivalent ions, dielectric contrasts, and external electric field on the ionic distributions. We observe the presence of non-monotonic ionic density profiles leading to a layered structure in the fluid which is attributed to the competition between electrostatic and steric (entropic) interactions. We find that thermal forces that arise from symmetry breaking at the interfaces can have a profound effect on the ionic structure and can oftentimes overwhelm the influence of the dielectric discontinuity. The combined effect of ionic correlations and inhomogeneous dielectric permittivity significantly changes the character of the effective interaction between the two interfaces.

  3. Direct regeneration of recycled cathode material mixture from scrapped LiFePO4 batteries

    NASA Astrophysics Data System (ADS)

    Li, Xuelei; Zhang, Jin; Song, Dawei; Song, Jishun; Zhang, Lianqi

    2017-03-01

    A new green recycling process (named as direct regeneration process) of cathode material mixture from scrapped LiFePO4 batteries is designed for the first time. Through this direct regeneration process, high purity cathode material mixture (LiFePO4 + acetylene black), anode material mixture (graphite + acetylene black) and other by-products (shell, Al foil, Cu foil and electrolyte solvent, etc.) are recycled from scrapped LiFePO4 batteries with high yield. Subsequently, recycled cathode material mixture without acid leaching is further directly regenerated with Li2CO3. Direct regeneration procedure of recycled cathode material mixture from 600 to 800 °C is investigated in detail. Cathode material mixture regenerated at 650 °C display excellent physical, chemical and electrochemical performances, which meet the reuse requirement for middle-end Li-ion batteries. The results indicate the green direct regeneration process with low-cost and high added-value is feasible.

  4. Effect of additive on electrochemical corrosion properties of plasma electrolytic oxidation coatings formed on CP Ti under different processing frequency

    NASA Astrophysics Data System (ADS)

    Babaei, Mahdi; Dehghanian, Changiz; Vanaki, Mojtaba

    2015-12-01

    The plasma electrolytic oxidation (PEO) coating containing zirconium oxide was fabricated on CP Ti at different processing frequencies viz., 100 Hz and 1000 Hz in a (Na2ZrO3, Na2SiO3)-additive containing NaH2PO4-based solution, and long-term electrochemical corrosion behavior of the coatings was studied using electrochemical impedance spectroscopy (EIS) in 3.5 wt.% NaCl solution. Electrochemical degradation behavior of two-layered coatings formed at different frequencies was turned out to be governed by concentration of electrolyte additive. With increasing additive concentration, the coating obtained at frequency of 1000 Hz exhibited enhanced corrosion resistance. However, corrosion resistance of the coating prepared at 100 Hz was found to decrease with increased additive, which was attributed to intensified microdischarges damaging the protective effect of inner layer. Nevertheless, the electrolyte additive was found to mitigate the long-term degradation of the coatings to a significant extent.

  5. Continuous process to produce lithium-polymer batteries

    DOEpatents

    Chern, T.S.H.; Keller, D.G.; MacFadden, K.O.

    1998-05-12

    Solid polymer electrolytes are extruded with active electrode material in a continuous, one-step process to form composite electrolyte-electrodes ready for assembly into battery cells. The composite electrolyte electrode sheets are extruded onto current collectors to form electrodes. The composite electrodes, as extruded, are electronically and ionically conductive. The composite electrodes can be over coated with a solid polymer electrolyte, which acts as a separator upon battery assembly. The interface between the solid polymer electrolyte composite electrodes and the solid polymer electrolyte separator has low resistance. 1 fig.

  6. Continuous process to produce lithium-polymer batteries

    DOEpatents

    Chern, Terry Song-Hsing; Keller, David Gerard; MacFadden, Kenneth Orville

    1998-01-01

    Solid polymer electrolytes are extruded with active electrode material in a continuous, one-step process to form composite electrolyte-electrodes ready for assembly into battery cells. The composite electrolyte-electrode sheets are extruded onto current collectors to form electrodes. The composite electrodes, as extruded, are electronically and ionically conductive. The composite electrodes can be overcoated with a solid polymer electrolyte, which acts as a separator upon battery assembly. The interface between the solid polymer electrolyte composite electrodes and the solid polymer electrolyte separator has low resistance.

  7. The Role of Sub- and Supercritical CO2 as "Processing Solvent" for the Recycling and Sample Preparation of Lithium Ion Battery Electrolytes.

    PubMed

    Nowak, Sascha; Winter, Martin

    2017-03-06

    Quantitative electrolyte extraction from lithium ion batteries (LIB) is of great interest for recycling processes. Following the generally valid EU legal guidelines for the recycling of batteries, 50 wt % of a LIB cell has to be recovered, which cannot be achieved without the electrolyte; hence, the electrolyte represents a target component for the recycling of LIBs. Additionally, fluoride or fluorinated compounds, as inevitably present in LIB electrolytes, can hamper or even damage recycling processes in industry and have to be removed from the solid LIB parts, as well. Finally, extraction is a necessary tool for LIB electrolyte aging analysis as well as for post-mortem investigations in general, because a qualitative overview can already be achieved after a few minutes of extraction for well-aged, apparently "dry" LIB cells, where the electrolyte is deeply penetrated or even gellified in the solid battery materials.

  8. Ceramic electrolyte coating methods

    DOEpatents

    Seabaugh, Matthew M.; Swartz, Scott L.; Dawson, William J.; McCormick, Buddy E.

    2004-10-12

    Processes for preparing aqueous suspensions of a nanoscale ceramic electrolyte material such as yttrium-stabilized zirconia. The invention also includes a process for preparing an aqueous coating slurry of a nanoscale ceramic electrolyte material. The invention further includes a process for depositing an aqueous spray coating slurry including a ceramic electrolyte material on pre-sintered, partially sintered, and unsintered ceramic substrates and products made by this process.

  9. Single Side Electrolytic In-Process Dressing (ELID) Grinding with Lapping Kinematics of Silicon Carbide

    NASA Astrophysics Data System (ADS)

    Khoshaim, Ahmed Bakr

    The demand for Silicon Carbide ceramics (SiC) has increased significantly in the last decade due to its reliable physical and chemical properties. The silicon carbide is widely used for aerospace segments in addition to many uses in the industry. Sometimes, a single side grinding is preferable than conventional grinding, for it has the ability to produce flat ceramics. However, the manufacturing cost is still high because of the high tool wear and long machining time. Part of the solution is to use electrolytic in process dressing (ELID) to reduce the processing time. The study on ELID single side grinding of ceramics has never been attempted before. The study involves four variables with three levels each. One of the variables, which is the eccentricity, is being investigated for the first time on ceramics. A full factorial design, for both the surface roughness and material removal rate, guides to calculate mathematical models that can predict future results. Three grinding wheel mesh sizes are used. An investigation of the influence of different grain size on the results can then be evaluated. The kinematics of the process was studied based on eccentricity in order to optimize the pattern of the diamond grains. The experiment is performed with the assist of the proposed specialized ELID fluid, TRIM C270E.

  10. Nonlinear optical and electro-optical properties of ionic lyotropic smectics with different impurities

    NASA Astrophysics Data System (ADS)

    Klimusheva, Gertruda; Bugaychuk, S.; Mirnaya, Tatyana; Vakhnin, Alexander; Kolesnik, O.

    2004-09-01

    Metal-organic ionic smectices (MOIS) have investigated to find their photorefractive properties. For the first time the multiplexing holographic recording of permanent gratings is obtained in pure lyotropic MOIS. It is proposed new mechanism of holographic recording in ionic smectics involving photo-chemical processes associated with multi-photon absorption. Dynamic grating recording has obtained in MOIS doped by electrochromic impurity (viologen) and in ionic smectic glasses composed by decanoate Co2+. A regeneration of viologen from radical state to initial molecule state becomes the main recording mechanism in MOIS with viologen impurity. Electronic absorption of Co2+ determines the recording of dynamic gratings in the ionic smectic glasses.

  11. Exceptionally stable polymer electrolyte for a lithium battery based on cross-linking by a residue-free process

    NASA Astrophysics Data System (ADS)

    Daigle, Jean-Christophe; Asakawa, Yuichiro; Vijh, Ashok; Hovington, Pierre; Armand, Michel; Zaghib, Karim

    2016-11-01

    In this paper, we report the synthesis of cross-linked copolymers of glycidyl methacrylate (GMA) and poly (ethylene glycol) methyl methacrylate (PEGMA) for use as solid polymer electrolytes (SPE). The cross-linking is performed with volatile ethylene diamine, thus preventing the accumulation of undesirable precursors in the final membrane. The structure of the cross-linked polymer electrolyte was investigated by 13C solid NMR and its physical properties were examined by DSC, TGA and stress-strain tests. The ionic conductivities were determined by AC Impedance, which showed that the SPEs have good conductivities (10-5 Scm-1) at 80 °C. The highest capacity measured with these polymers was 151 mAh g-1 at C/6 and 80 °C for a LFP/SPE/Lithium battery. The retention capacity is high, at 97% after 80 cycles at different rates of cycling. The Young's modulus of the membranes is as high as 1 GPa. The SEM images showed no evidence of lithium dendrites and no degradation after cycling. Therefore, the polymer is a good candidate for battery operation over a long time. Especially important is the ability of this polymer to prevent growth of dendrites on the Li-metal electrode.

  12. Recovery of salts from ion-exchange regeneration streams by a coupled nanofiltration-membrane distillation process.

    PubMed

    Jiříček, Tomáš; De Schepper, Wim; Lederer, Tomáš; Cauwenberg, Peter; Genné, Inge

    2015-01-01

    Ion-exchange tap water demineralization for process water preparation results in a saline regeneration wastewater (20-100 mS cm(-1)) that is increasingly problematic in view of discharge. A coupled nanofiltration-membrane distillation (NF-MD) process is evaluated for the recovery of water and sodium chloride from this wastewater. NF-MD treatment of mixed regeneration wastewater is compared to NF-MD treatment of separate anion- and cation-regenerate fractions. NF on mixed regeneration wastewater results in a higher flux (30 L m(-2) h(-1) at 7 bar) compared to NF on the separate fractions (6-9 L m(-2) h(-1) at 30 bar). NF permeate recovery is strongly limited by scaling (50% for separate and 60% for mixed, respectively). Physical signs of scaling were found during MD treatment of the NF permeates but did not result in flux decline for mixed regeneration wastewater. Final salt composition is expected to qualify as a road de-icing salt. NF-MD is an economically viable alternative compared to external disposal of wastewater for larger-scale installations (1.4 versus 2.5 euro m(-3) produced demineralized water for a 10 m3 regenerate per day plant). The cost benefits of water re-use and salt recuperation are small when compared to total treatment costs for mixed regenerate wastewater.

  13. Functionalized ionic liquids based on quaternary ammonium cations with two ether groups as new electrolytes for Li/LiFePO4 secondary battery

    NASA Astrophysics Data System (ADS)

    Jin, Yide; Zhang, Jianhao; Song, Jianzhi; Zhang, Zhengxi; Fang, Shaohua; Yang, Li; Hirano, Shin-ichi

    2014-05-01

    New functionalized ILs based on quaternary ammonium cations with two ether groups and bis(trifluoromethanesulfonyl)imide (TFSA-) anion are synthesized and characterized. Physical and electrochemical properties, including melting point, thermal stability, viscosity, conductivity and electrochemical stability are investigated for these ILs. All these ILs are liquids at room temperature except N,N-diethyl-N,N-bis(2-ethoxyethyl)ammonium TFSA (N22(2o2)(2o2)-TFSA, Tm = 29.7 °C), and the viscosities of N-methyl-N-ethyl-N-(2-methoxyethyl)-N-(2-ethoxyethyl)ammonium TFSA (N12(2o1)(2o2)-TFSA) and N-methyl-N-ethyl-N,N-bis(2-ethoxyethyl)ammonium TFSA (N12(2o2)(2o2)-TFSA) are 68.0 cP and 63.0 cP at 25 °C, respectively. N-Methyl-N,N-diethyl-N-(2-methoxyethyl)ammonium TFSA (DEME-TFSA) and five ILs with lower viscosity are chosen to dissolve 0.6 mol kg-1 of LiTFSA as IL electrolytes without additive for lithium battery. Lithium plating and striping on Ni electrode can be observed in these IL electrolytes, and cycle performances of lithium symmetrical cells are also investigated for these IL electrolytes. Li/LiFePO4 cells using these IL electrolytes without additives have good cycle property at the current rate of 0.1 C, and the N-methyl-N-ethyl-N,N-bis(2-methoxyethyl)ammonium TFSA (N12(2o1)(2o1)-TFSA) and N12(2o2)(2o2)-TFSA electrolytes own better rate property than DEME-TFSA electrolyte.

  14. Study of the Deburring Process for Low Carbon Steel by Plasma Electrolytic Oxidation

    NASA Astrophysics Data System (ADS)

    Li, Hongtao; Kan, Jinfeng; Jiang, Bailing; Liu, Yanjie; Liu, Zheng

    2016-08-01

    In an appropriate electrochemical environment, the discrete thermal electron emission could be induced in the micro area due to the uneven distribution of electron flux on the anode surface. Thus an oxygen molecule could be ionized at the liquid-solid interface after collision, and then oxygen plasma with distribution characteristics would be formed. The plasma electrolytic oxidation (PEO) could happen at the liquid-solid interface. In this work, the low carbon steel was used to study the deburring process by PEO at a high frequency (70000 Hz) pulse DC mode. Its burr height H from 3.23 mm to 0.04 mm was removed to form a smooth surface within 6 min. The values of corrosion potential and current density for the untreated sample were -0.667 V and 6.735×10-5 A/cm2, respectively. But for the treated sample, the corrosion potential and current density were relatively lower, -0.354 V and 1.19×10-7 A/cm2. Therefore, PEO was expected to be a new deburring method of carbon steel for the material processing field. supported by National Natural Science Foundation of China (No. 51571114) and Natural Science Foundation of Jiangsu Province, China (No. BK20130935)

  15. Analyses of quenching process during turn-off of plasma electrolytic carburizing on carbon steel

    NASA Astrophysics Data System (ADS)

    Wu, Jie; Liu, Run; Xue, Wenbin; Wang, Bin; Jin, Xiaoyue; Du, Jiancheng

    2014-10-01

    Plasma electrolytic carburizing (PEC) under different turn-off modes was employed to fabricate a hardening layer on carbon steel in glycerol solution without stirring at 380 V for 3 min. The quenching process in fast turn-off mode or slow turn-off mode of power supply was discussed. The temperature in the interior of steel and electron temperature in plasma discharge envelope during the quenching process were evaluated. It was found that the cooling rates of PEC samples in both turn-off modes were below 20 °C/s, because the vapor film boiling around the steel sample reduced the cooling rate greatly in terms of Leidenfrost effect. Thus the quench hardening hardly took place, though the slow turn-off mode slightly decreased the surface roughness of PEC steel. At the end of PEC treatment, the fast turn-off mode used widely at present cannot enhance the surface hardness by quench hardening, and the slow turn-off mode was recommended in order to protect the electronic devices against a large current surge.

  16. Treatment of actual effluents produced in the manufacturing of atrazine by a photo-electrolytic process.

    PubMed

    Aquino, José M; Miwa, Douglas W; Rodrigo, Manuel A; Motheo, Artur J

    2017-04-01

    The photo-assisted electrochemical degradation of a real effluent of the atrazine manufacturing process containing atrazine, simazine, hydroxy-triazine and propazine was carried out galvanostatically using a pilot-scale tubular flow reactor prototype containing DSA(®) and Ti as cathode. The effluent was mainly characterized by a high amount of NaCl, required in the synthesis route used, and it was used as taken in the factory. The variables for process optimization were the current density (3.0, 6.0, and 9.0 mA cm(-2)) and flow rate (300 and 3,000 L h(-1)). These later values produces laminar and turbulent flow regimes, with Reynolds numbers of 1,100 and 11,000, respectively. None of the four organics contained in the waste is refractory to the photo-electrochemical treatment and they are depleted with the photo-electrolytic technology using large current densities and appropriate electric charge passed. Both direct electrochemical process and mediated anodic oxidation occur during the treatment. First process occurs at turbulent flow condition and low current densities, while the chemical oxidation process happens at laminar flow condition and high current densities. Atrazine and propazine are efficiently removed at laminar flow conditions, with an almost total depletion for the largest current densities. On the contrary, simazine is efficiently removed in turbulent flow conditions and intermediate current density, with removals higher than 90% for 20 kWh m(-3). These results have great significance because they demonstrate the applicability of the electrochemical technology in the treatment of real industrial wastes with a cell specially designed to attain high efficiency in the removal of pollutants.

  17. Removal of herbicidal ionic liquids by electrochemical advanced oxidation processes combined with biological treatment.

    PubMed

    Pęziak-Kowalska, Daria; Fourcade, Florence; Niemczak, Michał; Amrane, Abdeltif; Chrzanowski, Łukasz; Lota, Grzegorz

    2016-09-12

    Recently a new group of ionic liquids (ILs) with herbicidal properties has been proposed for use in agriculture. Owing to the design of specific physicochemical properties, this group, referred to as herbicidal ionic liquids (HILs), allows for reducing herbicide field doses. Several ILs comprising phenoxy herbicides as anions and quaternary ammonium cations have been synthesized and tested under greenhouse and field conditions. However, since they are to be introduced into the environment, appropriate treatment technologies should be developed in order to ensure their proper removal and avoid possible contamination. In this study, didecyldimethylammonium (4-chloro-2-methylphenoxy) acetate was selected as a model HIL to evaluate the efficiency of a hybrid treatment method. Electrochemical oxidation or electro-Fenton was considered as a pretreatment step, whereas biodegradation was selected as the secondary treatment method. Both processes were carried out in current mode, at 10 mA with carbon felt as working electrode. The efficiency of degradation, oxidation and mineralization was evaluated after 6 h. Both processes decreased the total organic carbon and chemical oxygen demand (COD) values and increased the biochemical oxygen demand (BOD5) on the COD ratio to a value close to 0.4, showing that the electrolyzed solutions can be considered as 'readily biodegradable.'

  18. Composite Electrolyte for All-Solid-State Lithium Batteries: Low-Temperature Fabrication and Conductivity Enhancement.

    PubMed

    Lee, Sang-Don; Jung, Kyu-Nam; Kim, Hyeongil; Shin, Hyun-Seop; Song, Seung-Wan; Park, Min-Sik; Lee, Jong-Won

    2017-03-20

    All-solid-state lithium batteries offer notable advantages over conventional Li-ion batteries with liquid electrolytes in terms of energy density, stability, and safety. To realize this technology, it is critical to develop highly reliable solid-state inorganic electrolytes with high ionic conductivities and adequate processability. Li1+x Alx Ti2-x (PO4 )3 (LATP) with a NASICON (Na superionic conductor)-like structure is regarded as a potential solid electrolyte, owing to its high "bulk" conductivity (ca. 10(-3)  S cm(-1) ) and excellent stability against air and moisture. However, the solid LATP electrolyte still suffers from a low "total" conductivity, mainly owing to the blocking effect of grain boundaries to Li(+) conduction. In this study, an LATP-Bi2 O3 composite solid electrolyte shows very high total conductivity (9.4×10(-4)  S cm(-1) ) at room temperature. Bi2 O3 acts as a microstructural modifier to effectively reduce the fabrication temperature of the electrolyte and to enhance its ionic conductivity. Bi2 O3 promotes the densification of the LATP electrolyte, thereby improving its structural integrity, and at the same time, it facilitates Li(+) conduction, leading to reduced grain-boundary resistance. The feasibility of the LATP-Bi2 O3 composite electrolyte in all-solid-state Li batteries is also examined in this study.

  19. A morpholinium ionic liquid for cellulose dissolution.

    PubMed

    Raut, Dilip G; Sundman, Ola; Su, Weiqing; Virtanen, Pasi; Sugano, Yasuhito; Kordas, Krisztian; Mikkola, Jyri-Pekka

    2015-10-05

    A series of substituted morpholinium ionic salts and allyl ammonium acetates were prepared. Amongst those, N-allyl-N-methylmorpholinium acetate ([AMMorp][OAc]) was found to dissolve cellulose readily without any pre-processing of native cellulose. At 120°C, [AMMorp][OAc] could dissolve 30 wt%, 28 wt% and 25 wt% of cellulose with degree of polymerization (DPn) - 789, 1644 and 2082 respectively, in 20 min. Importantly, SEC analysis indicated that no discernible changes occurred in terms of the degree of polymerization of the different celluloses after regeneration. Furthermore, when comparing the cellulose dissolution capability of these newly synthesized ionic liquids, it is evident that the combination of all three constituents - the morpholinium cation, the existence of an allyl group and choosing the acetate anion are essential for efficient cellulose dissolution. The structure and morphology of the regenerated cellulosic materials were characterized by SEM, XRD, TGA, CP/MAS (13)C NMR and FTIR, respectively.

  20. Effect of molecular weight of oligomer on ionic diffusion in oligomer electrolytes and its implication for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Park, Jong Hyuk; Choi, Kyu Jin; Kim, Junkyung; Kang, Yong Soo; Lee, Sang-Soo

    This study measures the diffusion coefficients of I - and I 3 - in oligomer electrolytes as a function of the molecular weight of oligomers and investigates their effect on the performance of dye-sensitized solar cells (DSSCs). The high-diffusion coefficients of ions in an oligomer electrolyte with a lower molecular weight can help to promote the redox mechanism in DSSCs and thereby increase the short-circuit current density. They can also cause a decrease in the open-circuit voltage since a high-diffusion coefficient of I 3 - is capable of reducing the lifetime of electrons in TiO 2 electrodes. To offset these effects, N-methyl-benzimidazole is added to the oligomer electrolytes, thereby improving the open-circuit voltage and fill factor and, consequently, the overall energy-conversion efficiency, which increases to over 5%. A further test involving storage at a high temperature of 75 °C demonstrates that DSSCs employing the oligomer electrolytes show excellent thermal stability over 200 h.

  1. Laser-induced activation of regeneration processes in spine disc cartilage

    NASA Astrophysics Data System (ADS)

    Sobol, Emil N.; Vorobjeva, Natalia N.; Sviridov, Alexander P.; Omelchenko, Alexander I.; Baskov, Andrey V.; Shekhter, Anatoliy B.; Baskov, Vladimir A.; Feldchtein, Felix I.; Kamensky, Vladislav A.; Kuranov, Roman V.

    2000-05-01

    The effect of laser radiation on the regeneration processes in spine disk cartilage has been studied in-vivo. We used rabbits as a model and a Holmium (2.09 micrometer) and an Erbium fiber (1.56 micrometer) lasers for irradiation the discs which were preliminary opened to remove annulus fibrosus and the nucleus pulposus of the intervertebral disc. The irradiated zone has been examined using an optical coherent tomography in one month after the operation and conventional histological technique in two months after the laser operation. It has been shown that laser radiation promotes the growth of the new cartilaginous tissue of fibrous and hyaline types.

  2. Effect of a new regeneration process by adsorption-coagulation and flocculation on the physicochemical properties and the detergent efficiency of regenerated cleaning solutions.

    PubMed

    Blel, Walid; Dif, Mehdi; Sire, Olivier

    2015-05-15

    Reprocessing soiled cleaning-in-place (CIP) solutions has large economic and environmental costs, and it would be cheaper and greener to recycle them. In food industries, recycling of CIP solutions requires a suitable green process engineered to take into account the extreme physicochemical conditions of cleaning while not altering the process efficiency. To this end, an innovative treatment process combining adsorption-coagulation with flocculation was tested on multiple recycling of acid and basic cleaning solutions. In-depth analysis of time-course evolutions was carried out in the physicochemical properties (concentration, surface tension, viscosity, COD, total nitrogen) of these solutions over the course of successive regenerations. Cleaning and disinfection efficiencies were assessed based on both microbiological analyses and organic matter detachment and solubilization from fouled stainless steel surfaces. Microbiological analyses using a resistant bacterial strain (Bacillus subtilis spores) highlighted that solutions regenerated up to 20 times maintained the same bactericidal efficiency as de novo NaOH solutions. The cleanability of stainless steel surfaces showed that regenerated solutions allow better surface wettability, which goes to explain the improved detachment and solubilization found on different types of organic and inorganic fouling.

  3. Process for CO.sub.2 capture using a regenerable magnesium hydroxide sorbent

    DOEpatents

    Siriwardane, Ranjani V; Stevens, Jr., Robert W

    2013-06-25

    A process for CO.sub.2 separation using a regenerable Mg(OH).sub.2 sorbent. The process absorbs CO.sub.2 through the formation of MgCO.sub.3 and releases water product H.sub.2O. The MgCO.sub.3 is partially regenerated through direct contact with steam, which acts to heat the magnesium carbonate to a higher temperature, provide heat duty required to decompose the magnesium carbonate to yield MgO and CO.sub.2, provide an H.sub.2O environment over the magnesium carbonate thereby shifting the equilibrium and increasing the potential for CO.sub.2 desorption, and supply H.sub.2O for rehydroxylation of a portion of the MgO. The mixture is polished in the absence of CO.sub.2 using water product H.sub.2O produced during the CO.sub.2 absorption to maintain sorbent capture capacity. The sorbent now comprised substantially of Mg(OH).sub.2 is then available for further CO.sub.2 absorption duty in a cyclic process.

  4. Xiphoid process-derived chondrocytes: a novel cell source for elastic cartilage regeneration.

    PubMed

    Nam, Seungwoo; Cho, Wheemoon; Cho, Hyunji; Lee, Jungsun; Lee, EunAh; Son, Youngsook

    2014-11-01

    Reconstruction of elastic cartilage requires a source of chondrocytes that display a reliable differentiation tendency. Predetermined tissue progenitor cells are ideal candidates for meeting this need; however, it is difficult to obtain donor elastic cartilage tissue because most elastic cartilage serves important functions or forms external structures, making these tissues indispensable. We found vestigial cartilage tissue in xiphoid processes and characterized it as hyaline cartilage in the proximal region and elastic cartilage in the distal region. Xiphoid process-derived chondrocytes (XCs) showed superb in vitro expansion ability based on colony-forming unit fibroblast assays, cell yield, and cumulative cell growth. On induction of differentiation into mesenchymal lineages, XCs showed a strong tendency toward chondrogenic differentiation. An examination of the tissue-specific regeneration capacity of XCs in a subcutaneous-transplantation model and autologous chondrocyte implantation model confirmed reliable regeneration of elastic cartilage regardless of the implantation environment. On the basis of these observations, we conclude that xiphoid process cartilage, the only elastic cartilage tissue source that can be obtained without destroying external shape or function, is a source of elastic chondrocytes that show superb in vitro expansion and reliable differentiation capacity. These findings indicate that XCs could be a valuable cell source for reconstruction of elastic cartilage.

  5. Role of DDL processes during electrolytic reduction of Cu(II) in a low oxygen environment.

    PubMed

    Brosky, Rebekah T; Pamukcu, Sibel

    2013-11-15

    Heavy metals typically accumulate in reduced bottom sediments after being discharged into waterways by industrial and municipal processes. A laboratory experiment was conducted in order to determine if abundance of clay in the bottom sediments of a Cu-contaminated aqueous ecosystem could enhance electrolytic reduction of the heavy metal. Cu(NO3)2 · 2.5H2O was added to simulate a moderately contaminated system with 650 μg Cu/ml kaolinite clay-water slurry. A constant electrical potential of 1.0 V/cm was applied across platinum wire electrodes inserted into the continuously stirred system for four days while the system ORP(2) was monitored and periodic sub-samples were taken for analysis. The electrical as well as the chemical results indicate that the quantity of Cu(II) being reduced to Cu(I), especially within the aqueous phase, is increased within the first 48 h of experimentation by the presence of kaolinite clay up to 0.05 mg clay/l slurry.

  6. [Biological processes of the human environment regeneration within the Martian crew life support systems].

    PubMed

    Sychev, V N; Levinskikh, M A; Shepelev, E Ia; Podol'skiĭ, I G

    2003-01-01

    Five ground-based experiments at RF SRC-IBMP had the purpose to make a thorough investigation of a model of the human-unicellular algae-mineralization life support system. The system measured 15 m3 and contained 45 liters of alga suspension; the dry alga density was 10 to 12 g/l and water volume (including the alga suspension) amounted to 59 l. More sophisticated LSS models where algae were substituted by higher plants (crop area in the greenhouse equaled 15 m2) were investigated in three experiments from 1.5 mos. to 2 mos. in duration. It was found that the alga containing LSS was able to fulfill not only the macrofunction (air and water regeneration) but also several additional functions (air purification, establishment of microbial cenosis etc.) providing an adequate human environment. This polyfunctionality of the biological regenerative processes is a weighty argument for their integration into space LSSs. Another important aspect is that the unicellular algae containing systems are highly reliable owing to a huge number of species-cells which will be quickly recovered in case of the death of a part of the population and, consequently, functionality of the LSS autotrophic component will be restored before long. For an extended period of time the Martian crew will have no communication with the Earth's biosphere which implies that LSS should be absolutely reliable and redundant. Redundancy can be achieved through installation aboard the vehicle of two systems constructed on different principles of regeneration, i.e. physical-chemical and biological. Each of the LSSs should have the power to satisfy all needs of the crew. The best option is when two systems are functioning in parallel sharing the responsibility for the human environment. Redundancy in this case will mean that in the event of failure or a drastic decrease in performance of one system the other one will make up for the loss by increasing its share in the overall regeneration process.

  7. Electrochemical and in-situ X-ray diffraction studies of Ti3C2Tx MXene in ionic liquid electrolyte

    SciTech Connect

    Lin, Zifeng; Rozier, Patrick; Duployer, Benjamin; Taberna, Pierre -Louis; Anasori, Babak; Gogotsi, Yury G.; Simon, Patrice

    2016-08-26

    2D titanium carbide (Ti3C2Tx MXene) showed good capacitance in both organic and neat ionic liquid electrolytes, but its charge storage mechanism is still not fully understood. Here, electrochemical characteristics of Ti3C2Tx electrode were studied in neat EMI-TFSI electrolyte. A capacitive behavior was observed within a large electrochemical potential range (from – 1.5 to 1.5 V vs. Ag). Intercalation and de-intercalation of EMI+ cations and/or TFSI– anions were investigated by in-situ X-ray diffraction. Interlayer spacing of Ti3C2Tx flakes decreases during positive polarization, which can be ascribed to either electrostatic attraction effect between intercalated TFSI– anions and positively charged Ti3C2Tx nanosheets or steric effect caused by de-intercalation of EMI+ cations. In conclusion, the expansion of interlayer spacing when polarized to negative potentials is explained by steric effect of cation intercalation.

  8. Performance of magnetic activated carbon composite as peroxymonosulfate activator and regenerable adsorbent via sulfate radical-mediated oxidation processes.

    PubMed

    Oh, Wen-Da; Lua, Shun-Kuang; Dong, Zhili; Lim, Teik-Thye

    2015-03-02

    Magnetic activated carbon composite (CuFe2O4/AC, MACC) was prepared by a co-precipitation-calcination method. The MACC consisted of porous micro-particle morphology with homogeneously distributed CuFe2O4 and possessed high magnetic saturation moment (8.1 emu g(-1)). The performance of MACC was evaluated as catalyst and regenerable adsorbent via peroxymonosulfate (PMS, Oxone(®)) activation for methylene blue (MB) removal. Optimum CuFe2O4/AC w/w ratio was 1:1.5 giving excellent performance and can be reused for at least 3 cycles. The presence of common inorganic ions, namely Cl(-) and NO3(-) did not exert significant influence on MB degradation but humic acid decreased the MB degradation rate. As a regenerable adsorbent, negligible difference in regeneration efficiency was observed when a higher Oxone(®) dosage was employed but a better efficiency was obtained at a lower MACC loading. The factors hindering complete MACC regeneration are MB adsorption irreversibility and AC surface modification by PMS making it less favorable for subsequent MB adsorption. With an additional mild heat treatment (150 °C) after regeneration, 82% of the active sites were successfully regenerated. A kinetic model incorporating simultaneous first-order desorption, second-order adsorption and pseudo-first order degradation processes was numerically-solved to describe the rate of regeneration. The regeneration rate increased linearly with increasing Oxone(®):MACC ratio. The MACC could potentially serve as a catalyst for PMS activation and regenerable adsorbent.

  9. Rate limiting activity of charge transfer during lithiation from ionic liquids

    NASA Astrophysics Data System (ADS)

    Rodrigues, Marco-Tulio F.; Lin, Xinrong; Gullapalli, Hemtej; Grinstaff, Mark W.; Ajayan, Pulickel M.

    2016-10-01

    Given the increased use of room temperature ionic liquid electrolytes in Li-ion batteries, due to their non-flammability and negligible volatility, this study evaluates the lithiation kinetics to understand and improve the rate performance of Li-ion batteries. Lithium titanate spinel is used as a model electrode and the electrolyte is composed of LiTFSI and TFSI-coordinated alkoxy-modified phosphonium ionic liquid. Based on the analysis of activation energies for each process, we report that the charge-transfer reaction at the electrode/electrolyte interface is the rate-limiting step for cell operation. This finding is further supported by the observation that a 50-fold decrease in charge-transfer resistance at higher temperatures leads to a significant performance improvement over that of a traditional organic electrolyte at room temperature. Charge-transfer resistance and electrolyte wetting on the electrode surface are critical processes for optimal battery performance, and such processes need to be included when designing new ionic liquids in order to exceed the power density obtained with the use of current carbonate-based electrolytes.

  10. Synthesis of 8YSZ-LSGM Composite Thick Film Ceramics for Solid Electrolyte From Nanopowder Utilizing Local Zircon Prepared Using Sol Gel Process

    SciTech Connect

    Syarif, Dani Gustaman; Soepriyanto, Syoni; Korda, Akhmad; Ismunandar

    2010-10-24

    Thick film ceramics of 8% mol Y{sub 2}O{sub 3} doped-ZrO{sub 2}(8YSZ)-La{sub 0.8}Sr{sub 0.2}Ga{sub 0.2}Mg{sub 0.8}O{sub 3}(LSGM) composite for solid electrolyte have been synthesized from nanopowder. Concentration of LSGM was 0 and 10% weight. A paste for the thick films was made from 8YSZ nanopowder prepared using sol gel method and LSGM powder prepared by solid state reaction. Precursors for the 8YSZ nanopowder preparation were ZrOCl{sub 2{center_dot}}8H{sub 2}O derived from local zircon as byproduct of Tin processing at Bangka Island using caustic fusion method, and Y(NO{sub 3}){sub 3}. The thick films were produced by screen printing technique on alumina substrates. The films were sintered at 1500 deg. C for 2 hours in air. X-ray diffraction (XRD) data showed that the nanopowder of 8YSZ was well produced with broad peaks. The particle size of the 8YSZ powder was about 12 nm as calculated using Debye Scherrer method. The thick films of 8YSZ and 8YSZ-LSGM (90:10 in weight %) composite could be produced, however, the films still contain voids. The ionic conductance of the YSZ-10LSGM films was smaller than that of the YSZ films.

  11. A Direct Sulfation Process of a Marine Polysaccharide in Ionic Liquid

    PubMed Central

    Sinquin, Corinne; Ratiskol, Jacqueline; Weiss, Pierre; Cérantola, Stéphane; Le Bideau, Jean

    2015-01-01

    GY785 is an exopolysaccharide produced by a mesophilic bacterial strain Alteromonas infernus discovered in the deep-sea hydrothermal vents. GY785 highly sulfated derivative (GY785 DRS) was previously demonstrated to be a promising molecule driving the efficient mesenchymal stem cell chondrogenesis for cartilage repair. This glycosaminoglycan- (GAG-) like compound was modified in a classical solvent (N,N′-dimethylformamide). However, the use of classical solvents limits the polysaccharide solubility and causes the backbone degradation. In the present study, a one-step efficient sulfation process devoid of side effects (e.g., polysaccharide depolymerization and/or degradation) was developed to produce GAG-like derivatives. The sulfation of GY785 derivative (GY785 DR) was carried out using ionic liquid as a reaction medium. The successful sulfation of this anionic and highly branched heteropolysaccharide performed in ionic liquid would facilitate the production of new molecules of high specificity for biological targets such as tissue engineering or regenerative medicine. PMID:26090416

  12. Coherency strain and its effect on ionic conductivity and diffusion in solid electrolytes--an improved model for nanocrystalline thin films and a review of experimental data.

    PubMed

    Korte, C; Keppner, J; Peters, A; Schichtel, N; Aydin, H; Janek, J

    2014-11-28

    A phenomenological and analytical model for the influence of strain effects on atomic transport in columnar thin films is presented. A model system consisting of two types of crystalline thin films with coherent interfaces is assumed. Biaxial mechanical strain ε0 is caused by lattice misfit of the two phases. The conjoined films consist of columnar crystallites with a small diameter l. Strain relaxation by local elastic deformation, parallel to the hetero-interface, is possible along the columnar grain boundaries. The spatial extent δ0 of the strained hetero-interface regions can be calculated, assuming an exponential decay of the deformation-forces. The effect of the strain field on the local ionic transport in a thin film is then calculated by using the thermodynamic relation between (isostatic) pressure and free activation enthalpy ΔG(#). An expression describing the total ionic transport relative to bulk transport of a thin film or a multilayer as a function of the layer thickness is obtained as an integral average over strained and unstrained regions. The expression depends only on known material constants such as Young modulus Y, Poisson ratio ν and activation volume ΔV(#), which can be combined as dimensionless parameters. The model is successfully used to describe own experimental data from conductivity and diffusion studies. In the second part of the paper a comprehensive literature overview of experimental studies on (fast) ion transport in thin films and multilayers along solid-solid hetero-interfaces is presented. By comparing and reviewing the data the observed interface effects can be classified into three groups: (i) transport along interfaces between extrinsic ionic conductors (and insulator), (ii) transport along an open surface of an extrinsic ionic conductor and (iii) transport along interfaces between intrinsic ionic conductors. The observed effects in these groups differ by about five orders of magnitude in a very consistent way. The

  13. Regeneration of glass nanofluidic chips through a multiple-step sequential thermochemical decomposition process at high temperatures.

    PubMed

    Xu, Yan; Wu, Qian; Shimatani, Yuji; Yamaguchi, Koji

    2015-10-07

    Due to the lack of regeneration methods, the reusability of nanofluidic chips is a significant technical challenge impeding the efficient and economic promotion of both fundamental research and practical applications on nanofluidics. Herein, a simple method for the total regeneration of glass nanofluidic chips was described. The method consists of sequential thermal treatment with six well-designed steps, which correspond to four sequential thermal and thermochemical decomposition processes, namely, dehydration, high-temperature redox chemical reaction, high-temperature gasification, and cooling. The method enabled the total regeneration of typical 'dead' glass nanofluidic chips by eliminating physically clogged nanoparticles in the nanochannels, removing chemically reacted organic matter on the glass surface and regenerating permanent functional surfaces of dissimilar materials localized in the nanochannels. The method provides a technical solution to significantly improve the reusability of glass nanofluidic chips and will be useful for the promotion and acceleration of research and applications on nanofluidics.

  14. A novel dismantling process of waste printed circuit boards using water-soluble ionic liquid.

    PubMed

    Zeng, Xianlai; Li, Jinhui; Xie, Henghua; Liu, Lili

    2013-10-01

    Recycling processes for waste printed circuit boards (WPCBs) have been well established in terms of scientific research and field pilots. However, current dismantling procedures for WPCBs have restricted the recycling process, due to their low efficiency and negative impacts on environmental and human health. This work aimed to seek an environmental-friendly dismantling process through heating with water-soluble ionic liquid to separate electronic components and tin solder from two main types of WPCBs-cathode ray tubes and computer mainframes. The work systematically investigates the influence factors, heating mechanism, and optimal parameters for opening solder connections on WPCBs during the dismantling process, and addresses its environmental performance and economic assessment. The results obtained demonstrate that the optimal temperature, retention time, and turbulence resulting from impeller rotation during the dismantling process, were 250 °C, 12 min, and 45 rpm, respectively. Nearly 90% of the electronic components were separated from the WPCBs under the optimal experimental conditions. This novel process offers the possibility of large industrial-scale operations for separating electronic components and recovering tin solder, and for a more efficient and environmentally sound process for WPCBs recycling.

  15. Effect of Complexation of NaCl Salt with Polymer Blend (PEO/PVP) Electrolytes on Ionic Conductivity and Optical Energy Band Gaps

    NASA Astrophysics Data System (ADS)

    Kumar, K. Kiran; Pavani, Y.; Ravi, M.; Bhavani, S.; Sharma, A. K.; Rao, V. V. R. Narasimha

    2011-10-01

    Sodium ion conducting polymer blend electrolyte films, based on polyethylene oxide (PEO) and poly vinyl pyrrolidone (PVP) complexed with NaCl salt, were prepared using solution casting technique. The complexation of the salt with the polymer blend was confirmed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and UV-vis spectroscopy. Frequency and temperature dependence of electrical conductivity of the films was studied with impedance analyzer in the frequency range of 1 Hz to 1 MHz and in the temperature range of 303-348 K. UV-vis absorption spectra in wavelength region 200-800 nm, were used to evaluate the optical properties like direct and indirect optical energy band gaps, optical absorption edge. The optical band gaps decreased with the increase of Na+ ion concentration. This suggests that NaCl, as dopant, is a good choice to improve the electrical and optical properties of PEO/PVP polymer blend electrolytes.

  16. Glass electrolyte composition

    DOEpatents

    Kucera, Gene H.; Roche, Michael F.

    1985-01-01

    An ionically conductive glass is disclosed for use as electrolyte in a high temperature electrochemical cell, particularly a cell with sodium anode and sulfur cathode. The glass includes the constituents Na.sub.2 O, ZrO.sub.2, Al.sub.2 O.sub.3 and SiO.sub.2 in selected proportions to be a single phase solid solution substantially free of crystalline regions and undissolved constituents. Other advantageous properties are an ionic conductivity in excess of 2.times.10.sup.-3 (ohm-cm).sup.-1 at 300.degree. C. and a glass transition temperature in excess of 500.degree. C.

  17. Glass electrolyte composition

    DOEpatents

    Kucera, G.H.; Roche, M.F.

    1985-01-08

    An ionically conductive glass is disclosed for use as electrolyte in a high temperature electrochemical cell, particularly a cell with sodium anode and sulfur cathode. The glass includes the constituents Na/sub 2/O, ZrO/sub 2/, Al/sub 2/O/sub 3/ and SiO/sub 2/ in selected proportions to be a single phase solid solution substantially free of crystalline regions and undissolved constituents. Other advantageous properties are an ionic conductivity in excess of 2 x 10/sup -3/ (ohm-cm)/sup -1/ at 300/sup 0/C and a glass transition temperature in excess of 500/sup 0/C.

  18. Computational and Experimental Investigation of Li-doped Ionic Liquid Electrolytes: [pyr14][tfsi], [pyr13][fsi], and [EMIM][BF4

    NASA Technical Reports Server (NTRS)

    Haskins, Justin B.; Bennett, William R.; Wu, James J.; Hernandez, Dionne M.; Borodin, Oleg; Monk, Joshua D.; Bauschlicher, Charles W.; Lawson, John W.

    2014-01-01

    We employ molecular dynamics (MD) simulation and experiment to investigate the structure, thermodynamics, and transport of N-methyl-N-butylpyrrolidinium bis(trifluoromethylsufonyl)imide ([pyr14][TFSI]), N -methyl-N-propylpyrrolidinium bis(fluorosufonyl)imide ([pyr13][FSI]), and 1-ethyl-3-methylimidazolium boron tetrafluoride ([EMIM][BF4]), as a function of Li-salt mole fraction (0.05 xLi+ 0.33) and temperature (298 K T 393 K). Structurally, Li+ is shown to be solvated by three anion neigh- bors in [pyr14][TFSI] and four anion neighbors in both [pyr13][FSI] and [EMIM][BF4], and at all levels of xLi+ we find the presence of lithium aggregates. Pulsed field gradient spin-echo NMR measurements of diffusion and electrochemical impedance spectroscopy measurements of ionic conductivity are made for the neat ionic liquids as well as 0.5 molal solutions of Li-salt in the ionic liquids. Bulk ionic liquid properties (density, diffusion, viscosity, and ionic conductivity) are obtained with MD and show excellent agreement with experiment. While the diffusion exhibits a systematic decrease with increasing xLi+, the contribution of Li+ to ionic conductivity increases until reach- ing a saturation doping level of xLi+ 0.10. Comparatively, the Li+ conductivity of [pyr14][TFSI] is an order of magnitude lower than that of the other liquids, which range between 0.1-0.3 mScm. Our transport results also demonstrate the necessity of long MD simulation runs ( 200 ns) required to converge transport properties at room T. The differences in Li+ transport are reflected in the residence times of Li+ with the anions (Li), which are revealed to be much larger for [pyr14][TFSI] (up to 100 ns at the highest doping levels) than in either [EMIM][BF4] or [pyr13][FSI]. Finally, to comment on the relative kinetics of Li+ transport in each liquid, we find that while the net motion of Li+ with its solvation shell (vehicular) significantly contributes to net diffusion in all liquids, the importance of

  19. Li2OHCl crystalline electrolyte for stable metallic lithium anodes

    SciTech Connect

    Hood, Zachary D.; Wang, Hui; Samuthira Pandian, Amaresh; Keum, Jong Kahk; Liang, Chengdu

    2016-01-22

    In a classic example of stability from instability, we show that Li2OHCl solid electrolyte forms a stable solid electrolyte interface (SEI) with metallic lithium anode. The Li2OHCl solid electrolyte can be readily achieved through simple mixing of air-stable LiOH and LiCl precursors with a mild processing temperature under 400 °C. Additionally, we show that continuous, dense Li2OHCl membranes can be fabricated at temperatures less than 400 °C, standing in great contrast to current processing temperatures of over 1600 °C for most oxide-based solid electrolytes. The ionic conductivity and Arrhenius activation energy were explored for the LiOH-LiCl system of crystalline solid electrolytes where Li2OHCl with increased crystal defects was found to have the highest ionic conductivity and reasonable Arrhenius activation energy. The Li2OHCl solid electrolyte displays stability against metallic lithium, even in extreme conditions past the melting point of lithium metal. Furthermore, to understand this excellent stability, we show that SEI formation is critical in stabilizing the interface between metallic lithium and the Li2OHCl solid electrolyte.

  20. Polymer-ionic liquid ternary systems for Li-battery electrolytes: Molecular dynamics studies of LiTFSI in a EMIm-TFSI and PEO blend

    SciTech Connect

    Costa, Luciano T.

    2015-07-14

    This paper presents atomistic molecular dynamics simulation studies of lithium bis(trifluoromethane)sulfonylimide (LiTFSI) in a blend of 1-ethyl-3-methylimidazolium (EMIm)-TFSI and poly(ethylene oxide) (PEO), which is a promising electrolyte material for Li- and Li-ion batteries. Simulations of 100 ns were performed for temperatures between 303 K and 423 K, for a Li:ether oxygen ratio of 1:16, and for PEO chains with 26 EO repeating units. Li{sup +} coordination and transportation were studied in the ternary electrolyte system, i.e., PEO{sub 16}LiTFSI⋅1.0 EMImTFSI, by applying three different force field models and are here compared to relevant simulation and experimental data. The force fields generated significantly different results, where a scaled charge model displayed the most reasonable comparisons with previous work and overall consistency. It is generally seen that the Li cations are primarily coordinated to polymer chains and less coupled to TFSI anion. The addition of EMImTFSI in the electrolyte system enhances Li diffusion, associated to the enhanced TFSI dynamics observed when increasing the overall TFSI anion concentration in the polymer matrix.

  1. Polymer-ionic liquid ternary systems for Li-battery electrolytes: Molecular dynamics studies of LiTFSI in a EMIm-TFSI and PEO blend.

    PubMed

    Costa, Luciano T; Sun, Bing; Jeschull, Fabian; Brandell, Daniel

    2015-07-14

    This paper presents atomistic molecular dynamics simulation studies of lithium bis(trifluoromethane)sulfonylimide (LiTFSI) in a blend of 1-ethyl-3-methylimidazolium (EMIm)-TFSI and poly(ethylene oxide) (PEO), which is a promising electrolyte material for Li- and Li-ion batteries. Simulations of 100 ns were performed for temperatures between 303 K and 423 K, for a Li:ether oxygen ratio of 1:16, and for PEO chains with 26 EO repeating units. Li(+) coordination and transportation were studied in the ternary electrolyte system, i.e., PEO16LiTFSI⋅1.0 EMImTFSI, by applying three different force field models and are here compared to relevant simulation and experimental data. The force fields generated significantly different results, where a scaled charge model displayed the most reasonable comparisons with previous work and overall consistency. It is generally seen that the Li cations are primarily coordinated to polymer chains and less coupled to TFSI anion. The addition of EMImTFSI in the electrolyte system enhances Li diffusion, associated to the enhanced TFSI dynamics observed when increasing the overall TFSI anion concentration in the polymer matrix.

  2. Polymer-ionic liquid ternary systems for Li-battery electrolytes: Molecular dynamics studies of LiTFSI in a EMIm-TFSI and PEO blend

    NASA Astrophysics Data System (ADS)

    Costa, Luciano T.; Sun, Bing; Jeschull, Fabian; Brandell, Daniel

    2015-07-01

    This paper presents atomistic molecular dynamics simulation studies of lithium bis(trifluoromethane)sulfonylimide (LiTFSI) in a blend of 1-ethyl-3-methylimidazolium (EMIm)-TFSI and poly(ethylene oxide) (PEO), which is a promising electrolyte material for Li- and Li-ion batteries. Simulations of 100 ns were performed for temperatures between 303 K and 423 K, for a Li:ether oxygen ratio of 1:16, and for PEO chains with 26 EO repeating units. Li+ coordination and transportation were studied in the ternary electrolyte system, i.e., PEO16LiTFSIṡ1.0 EMImTFSI, by applying three different force field models and are here compared to relevant simulation and experimental data. The force fields generated significantly different results, where a scaled charge model displayed the most reasonable comparisons with previous work and overall consistency. It is generally seen that the Li cations are primarily coordinated to polymer chains and less coupled to TFSI anion. The addition of EMImTFSI in the electrolyte system enhances Li diffusion, associated to the enhanced TFSI dynamics observed when increasing the overall TFSI anion concentration in the polymer matrix.

  3. Performance evaluation of titanium dioxide based dye-sensitized solar cells under the influence of anodization steps, nanotube length and ionic liquid-free redox electrolyte solvents

    NASA Astrophysics Data System (ADS)

    Cheong, Y. L.; Beh, K. P.; Yam, F. K.; Hassan, Z.

    2016-06-01

    In this work, highly ordered titanium dioxide (TiO2) nanotube (NT) arrays were synthesized on titanium foil using electrochemical anodization method. The morphological aspects of the nanotubes based on different anodization duration and number of anodization steps (maximum two) have been investigated. The nanotube arrays subsequently used as photoanode in a dye-sensitized solar cell (DSSC) assembly. The studies on the effects of different solvents for triiodide/iodide redox electrolyte and NT length towards the performance of DSSC were conducted. It is known that electrolyte solvent can significantly affect the photovoltaic conversion efficiency. It is noteworthy that longer NT length tends to yield higher efficiency due to better dye adsorption. However, when the NTs exceeded certain length the efficiency decreases instead. Meanwhile, a comparison of DSSC performance based on number of anodization steps on titanium was performed. Highly ordered NT arrays could be obtained using two-steps anodization, which proved to have positive effects on the DSSC performance. The highest photovoltaic conversion efficiency in this work is 2.04%, achieved by two-step anodization. The corresponding average nanotubes length was ˜18 μm, with acetonitrile (ACN) as the redox electrolyte solvent.

  4. Clean surface processing of rubrene single crystal immersed in ionic liquid by using frequency modulation atomic force microscopy

    SciTech Connect

    Yokota, Yasuyuki; Hara, Hisaya; Morino, Yusuke; Bando, Ken-ichi; Imanishi, Akihito; Fukui, Ken-ichi; Uemura, Takafumi; Takeya, Jun

    2014-06-30

    Surface processing of a rubrene single crystal immersed in ionic liquids is valuable for further development of low voltage transistors operated by an electric double layer. We performed a precise and clean surface processing based on the tip-induced dissolution of rubrene molecules at the ionic liquid/rubrene single crystal interfaces by using frequency modulation atomic force microscopy. Molecular resolution imaging revealed that the tip-induced dissolution proceeded via metastable low density states derived from the anisotropic intermolecular interactions within the crystal structure.

  5. Factors governing dissolution process of lignocellulosic biomass in ionic liquid: current status, overview and challenges.

    PubMed

    Badgujar, Kirtikumar C; Bhanage, Bhalchandra M

    2015-02-01

    The utilisation of non-feed lignocellulosic biomass as a source of renewable bio-energy and synthesis of fine chemical products is necessary for the sustainable development. The methods for the dissolution of lignocellulosic biomass in conventional solvents are complex and tedious due to the complex chemical ultra-structure of biomass. In view of this, recent developments for the use of ionic liquid solvent (IL) has received great attention, as ILs can solubilise such complex biomass and thus provides industrial scale-up potential. In this review, we have discussed the state-of-art for the dissolution of lignocellulosic material in representative ILs. Furthermore, various process parameters and their influence for biomass dissolution were reviewed. In addition to this, overview of challenges and opportunities related to this interesting area is presented.

  6. TGF-β signaling is required for multiple processes during Xenopus tail regeneration

    PubMed Central

    Ho, Diana M.; Whitman, Malcolm

    2008-01-01

    Xenopus tadpoles can fully regenerate all major tissue types following tail amputation. TGF-β signaling plays essential roles in growth, repair, specification, and differentiation of tissues throughout development and adulthood. We examined the localization of key components of the TGF-β signaling pathway during regeneration and characterized the effects of loss of TGF-β signaling on multiple regenerative events. Phosphorylated Smad2 (p-Smad2) is initially restricted to the p63+ basal layer of the regenerative epithelium shortly after amputation, and is later found in multiple tissue types in the regeneration bud. TGF-β ligands are also upregulated throughout regeneration. Treatment of amputated tails with SB-431542, a specific and reversible inhibitor of TGF-β signaling, blocks tail regeneration at multiple points. Inhibition of TGF-β signaling immediately following tail amputation reversibly prevents formation of a wound epithelium over the future regeneration bud. Even brief inhibition immediately following amputation is sufficient, however, to irreversibly block the establishment of structures and cell types that characterize regenerating tissue and to prevent the proper activation of BMP and ERK signaling pathways. Inhibition of TGF-β signaling after regeneration has already commenced blocks cell proliferation in the regeneration bud. These data reveal several spatially and temporally distinct roles for TGF-β signaling during regeneration: 1) wound epithelium formation, 2) establishment of regeneration bud structures and signaling cascades, and 3) regulation of cell proliferation. PMID:18234181

  7. Technical feasibility study of electrolytic ion transfer membranes for radioactive liquid waste processing

    SciTech Connect

    Not Available

    1982-08-11

    Results are presented of a test program designed to determine the technical feasibility of INNOVA Ion Transfer Membranes (ITM) to separate radionuclides from waste streams at N Reactor. The ITM system was tested using the following test solutions, which either chemically simulated or duplicated the radioactive waste streams generated at N Reactor: TURCO 4512A - /sup 59/Co, 4% Na/sub 2/So/sub 4/ - /sup 59/Fe, and Ion Exchange Resin Regeneration (IXR) waste from an irradiated fuel storage basin. In addition, the ITM construction material was tested to determine its resistance to a radioactive environment. To assure that the ITM membranes could withstand a radioactive environment, samples of the ITM membrane material were exposed to high doses of gamma radiation and then tested for change in burst strength. The irradiated membranes did not show significant signs of degradation until a total gamma radiation exposure of 10/sup 7/ Rads was reached. Extrapolation of this data strongly suggests that the membrane life expectancy in a radiation environment is good. The following recommendations were made. Sequential unialysis be investigated for processing IXR waste. Reactor Decontamination Waste be treated by the Oxidation Reduction Coagulation cell prior to ITM processing to confirm pre-treatment feasibility. The Oxidation Reduction Coagulation cell be developed for other N Area applications. An ITM unialysis system be developed for selective radionuclide extraction from irradiated fuel storage basins. The ITM economic feasibility be determined on the applications tested in this report. A unialysis ITM system be tested for extraction of radionuclides from electropolish decontamination wastes.

  8. Phase behavior of 1-dodecyl-3-methylimidazolium fluorohydrogenate salts (C12MIm(FH)(n)F, n = 1.0-2.3) and their anisotropic ionic conductivity as ionic liquid crystal electrolytes.

    PubMed

    Xu, Fei; Matsumoto, Kazuhiko; Hagiwara, Rika

    2012-08-23

    The effects of the HF composition, n, in 1-dodecyl-3-methylimidazolium fluorohydrogenate salts (C(12)MIm(FH)(n)F, n = 1.0-2.3) on their physicochemical and structural properties have been investigated using infrared spectroscopy, thermal analysis, polarized optical microscopy, X-ray diffraction, and anisotropic ionic conductivity measurements. The phase diagram of C(12)MIm(FH)(n)F (n vs transition temperature) suggests that C(12)MIm(FH)(n)F is a mixed crystal system that has a boundary around n = 1.9. For all compositions, a liquid crystalline mesophase with a smectic A interdigitated bilayer structure is observed. The temperature range of the mesophase decreases with increasing n value (from 61.8 °C for C(12)MIm(FH)(1.0)F to 37.0 °C for C(12)MIm(FH)(2.3)F). The layer spacing of the smectic structure decreases with increasing n value or increasing temperature. Two structural types with different layer spacings are observed in the crystalline phase (type I, 1.0 ≤ n ≤ 1.9, and type II, 1.9 ≤ n ≤ 2.3). Ionic conductivities parallel and perpendicular to the smectic layers (σ(||) and σ([perpendicular])) increase with increasing n value, whereas the anisotropy of the ionic conductivities (σ(||)/σ([perpendicular])) is independent of the n value, since the thickness of the insulating sheet formed by the dodecyl group remains nearly unchanged.

  9. Wear Protection of AJ62 Mg Engine Blocks using Plasma Electrolytic Oxidation Process

    NASA Astrophysics Data System (ADS)

    Zhang, Peng

    2011-12-01

    In order to reduce the fuel consumption and pollution, automotive companies are developing magnesium-intensive components. However, due to the low wear resistance of the magnesium (Mg) alloys, Mg cylinder bores are vulnerable to the sliding wear attack. In this thesis, two approaches were used to protect the cylinder bores, made of a new developed Mg engine alloy AJ62 (MgA16Mn0.34Sr2). The first one was to use a Plasma Electrolytic Oxidation (PEO) process to produce oxide coatings on the Mg bores. The wear properties of the PEO coatings were evaluated by sliding wear tests under the boundary lubrication condition at the room and elevated temperatures. It was found that due to the substrate softening and the vaporization loss of the lubricant, the tribological properties of the PEO coatings were deteriorated at the elevated temperature. In order to optimize the PEO process, a statistical method (Response surface method) was used to analyze the effects of the 4 main PEO process parameters with 2 levels for each and their interactions on the tribological properties of the PEO coatings at the room and elevated temperatures, individually. A cylinder liner made of an economical metal-matrix composite (MMC) was another approach to improve the wear resistance of the Mg cylinder bore. In this thesis, an A1383/SiO2 MMC was designed to replace the expensive Alusil alloy used in the BMW Mg/Al composite engine to build the cylinder liner. To further increase the wear resistance of the MMC, PEO process was also used to form an oxide coating on the MMC. The effects of the SiO 2 content and coating thickness on the tribological properties of the MMC were studied. To evaluate the wear properties of the optimal PEO coated Mg coupons and the MMC with the oxide coatings, Alusil and cast iron, currently used on the cylinder bores of the commercial aluminum engines, were used as reference materials. The optimal PEO coated Mg coupons and the oxidized MMC showed their advantages over the

  10. Electrolyte compositions for lithium ion batteries

    SciTech Connect

    Sun, Xiao-Guang; Dai, Sheng; Liao, Chen

    2016-03-29

    The invention is directed in a first aspect to an ionic liquid of the general formula Y.sup.+Z.sup.-, wherein Y.sup.+ is a positively-charged component of the ionic liquid and Z.sup.- is a negatively-charged component of the ionic liquid, wherein Z.sup.- is a boron-containing anion of the following formula: ##STR00001## The invention is also directed to electrolyte compositions in which the boron-containing ionic liquid Y.sup.+Z.sup.- is incorporated into a lithium ion battery electrolyte, with or without admixture with another ionic liquid Y.sup.+X.sup.- and/or non-ionic solvent and/or non-ionic solvent additive.

  11. Multipotent epithelial cells in the process of regeneration and asexual reproduction in colonial tunicates.

    PubMed

    Kawamura, Kazuo; Sugino, Yasuo; Sunanaga, Takeshi; Fujiwara, Shigeki

    2008-01-01

    The cellular and molecular features of multipotent epithelial cells during regeneration and asexual reproduction in colonial tunicates are described in the present study. The epicardium has been regarded as the endodermal tissue-forming epithelium in the order Enterogona, because only body fragments having the epicardium exhibit the regenerative potential. Epicardial cells in Polycitor proliferus have two peculiar features; they always accompany coelomic undifferentiated cells, and they contain various kinds of organelles in the cytoplasm. During strobilation a large amount of organelles are discarded in the lumen, and then, each tissue-forming cell takes an undifferentiated configuration. Septum cells in the stolon are also multipotent in Enterogona. Free cells with a similar configuration to the septum inhabit the hemocoel. They may provide a pool for epithelial septum cells. At the distal tip of the stolon, septum cells are columnar in shape and apparently undifferentiated. They are the precursor of the stolonial bud. In Pleurogona, the atrial epithelium of endodermal origin is multipotent. In Polyandrocarpa misakiensis, it consists of pigmented squamous cells. The cells have ultrastructurally fine granules in the cytoplasm. During budding, coelomic cells with similar morphology become associated with the atrial epithelium. Then, cells of organ placodes undergo dedifferentiation, enter a cell division cycle, and commence morphogenesis. Retinoic acid-related molecules are involved in this dedifferentiation process of multipotent cells. We conclude that in colonial tunicates two systems support the flexibility of tissue remodeling during regeneration and asexual reproduction; dedifferentiation of epithelial cells and epithelial transformation of coelomic free cells.

  12. Annealing Would Improve beta" - Alumina Solid Electrolyte

    NASA Technical Reports Server (NTRS)

    Williams, Roger; Homer, Margie; Ryan, Margaret; Cortez, Roger; Shields, Virgil; Kisor, Adam

    2003-01-01

    A pre-operational annealing process is under investigation as a potential means of preventing a sudden reduction of ionic conductivity in a Beta"-alumina solid electrolyte (BASE) during use. On the basis of tests, the sudden reduction of ionic conductivity, followed by a slow recovery, has been found to occur during testing of the solid electrolyte and electrode components of an alkali metal thermal-to-electric converter (AMTEC) cell. At this time, high-temperature tests of limited duration have indicated the superiority of the treated BASE, but reproducible tests over thousands of hours are necessary to confirm that microcracking has been eliminated. The ionic conductivity of the treated BASE is also measured to be higher than untreated BASE at 1,073 K in low-pressure sodium vapor. Microcracking resulting in loss of conductivity was not observed with treated BASE in one high-temperature experiment, but this result must be duplicated over very long testing times to be sure of the effect. Shorter annealing times (10 to 20 hours) were found to result in significantly less loss of mass; it may be necessary for the packed powder mixture to evolve some Na2O before the Na2O can leave the ceramic.

  13. Optimization of non-aqueous electrolytes for Primary lithium/air batteries operated in Ambient Enviroment

    SciTech Connect

    Xu, Wu; Xiao, Jie; Zhang, Jian; Wang, Deyu; Zhang, Jiguang

    2009-07-07

    The selection and optimization of non-aqueous electrolytes for ambient operations of lithium/air batteries has been studied. Organic solvents with low volatility and low moisture absorption are necessary to minimize the change of electrolyte compositions and the reaction between lithium anode and water during discharge process. It is critical to make the electrolytes with high polarity so that it can reduce wetting and flooding of carbon based air electrode and lead to improved battery performance. For ambient operations, the viscosity, ionic conductivity, and oxygen solubility of the electrolyte are less important than the polarity of organic solvents once the electrolyte has reasonable viscosity, conductivity, and oxygen solubility. It has been found that PC/EC mixture is the best solvent system and LiTFSI is the most feasible salt for ambient operations of Li/air batteries. Battery performance is not very sensitive to PC/EC ratio or salt concentration.

  14. Viscoelastic Properties, Ionic Conductivity, and Materials Design Considerations for Poly(styrene-b-ethylene oxide-b-styrene)-Based Ion Gel Electrolytes

    SciTech Connect

    Zhang, Sipei; Lee, Keun Hyung; Sun, Jingru; Frisbie, C. Daniel; Lodge, Timothy P.

    2013-03-07

    The viscoelastic properties and ionic conductivity of ion gels based on the self-assembly of a poly(styrene-b-ethylene oxide-b-styrene) (SOS) triblock copolymer (M{sub n,S} = 3 kDa, M{sub n,O} = 35 kDa) in the ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide ([EMI][TFSA]) were investigated over the composition range of 10-50 wt % SOS and the temperature range of 25-160 C. The poly(styrene) (PS) end-blocks associate into micelles, whereas the poly(ethylene oxide) (PEO) midblocks are well-solvated by this ionic liquid. The ion gel with 10 wt % SOS melts at 54 C, with the longest relaxation time exhibiting a similar temperature dependence to that of the viscosity of bulk PS. However, the actual values of the gel relaxation time are more than 4 orders of magnitude larger than the relaxation time of bulk PS. This is attributed to the thermodynamic penalty of pulling PS end-blocks through the PEO/[EMI][TFSA] matrix. Ion gels with 20-50 wt % SOS do not melt and show two plateaus in the storage modulus over the temperature and frequency ranges measured. The one at higher frequencies is that of an entangled network of PEO strands with PS cross-links; the modulus displays a quadratic dependence on polymer weight fraction and agrees with the prediction of linear viscoelastic theory assuming half of the PEO chains are elastically effective. The frequency that separates the two plateaus, {omega}{sub c}, reflects the time scale of PS end-block pull-out. The other plateau at lower frequencies is that of a congested micelle solution with PS cores and PEO coronas, which has a power law dependence on domain spacing similar to diblock melts. The ionic conductivity of the ion gels is compared to PEO homopolymer solutions at similar polymer concentrations; the conductivity is reduced by a factor of 2.1 or less, decreases with increasing PS volume fraction, and follows predictions based on a simple obstruction model. Our collective results allow the formulation

  15. Thin film composite electrolyte

    DOEpatents

    Schucker, Robert C.

    2007-08-14

    The invention is a thin film composite solid (and a means for making such) suitable for use as an electrolyte, having a first layer of a dense, non-porous conductive material; a second layer of a porous ionic conductive material; and a third layer of a dense non-porous conductive material, wherein the second layer has a Coefficient of thermal expansion within 5% of the coefficient of thermal expansion of the first and third layers.

  16. A molecular dynamic model for analyzing concentrations of electrolytes: Fractional molar dependences of microstructure properties

    NASA Astrophysics Data System (ADS)

    Khalansky, D.; Popova, E.; Gladyshev, P.; Dushanov, E.; Kholmurodov, Kh.

    2014-12-01

    Aqueous electrolyte solutions play an important role in many electrophysical and chemical processes in aerospace technology and industrial applications. As noncovalent interactions, the interactions between ions are crucially important for biomolecular structures as well (protein structure folding, molecular level processes followed by ionic pair correlations, the formation of flexible hydrate shells, and so on). Specifically, ions (cations and anions with the same valence charges) can form stable pairs if their sizes match. The formation of ionic pairs can substantially affect the thermodynamic stabilities of proteins in the alkali salts physiologically present in the human body. Research aims and problems impose severe demands on readjustments of the ionic force fields and potential parameters developed to describe aqueous solutions and electrolytic systems. Ionic solutions and their interaction with biomolecules have been observed for over 100 years [1], but the behavior of such solutions remains poorly studied today. New data obtained in this work deals with parameterization strategies and adjustments for the ionic force fields of the alkali cations and halide anions that should be helpful in biomolecular research. Using molecular dynamics (MD) models, four electrolytic systems (HCl-H2O, LiCl-H2O, NaCl-H2O, and KCl-H2O) are investigated as binary mixtures of water and cations and anions, respectively. The intermolecular interaction parameters are varied for two of the four model electrolytes (HCl-H2O and NaCl-H2O) to simulate the possibility of different ionic shells forming during interaction with water. It is found that varying the potential parameters strongly affects the dynamic and structural characteristics of electrolyte systems. MD simulations are performed in the temperature range of 300 to 600 K with a step of 50 K. MD simulations for all electrolyte models (HCl-H2O, LiCl-H2O, NaCl-H2O, KCl-H2O) are also conducted for different molar fractions of

  17. Recovery and regeneration of spent MHD seed material by the formate process

    DOEpatents

    Sheth, Atul C.; Holt, Jeffrey K.; Rasnake, Darryll G.; Solomon, Robert L.; Wilson, Gregory L.; Herrigel, Howard R.

    1991-01-01

    The specification discloses a spent seed recovery and regeneration process for an MHM power plant employing an alkali metal salt seed material such as potassium salt wherein the spent potassium seed in the form of potassium sulfate is collected from the flue gas and reacted with calcium hydroxide and carbon monoxide in an aqueous solution to cause the formation of calcium sulfate and potassium formate. The pH of the solution is adjusted to supress formation of formic acid and to promote precipitation of any dissolved calcium salts. The solution containing potassium formate is then employed to provide the potassium salt in the form of potassium formate or, optionally, by heating the potassium formate under oxidizing conditions to convert the potassium formate to potassium carbonate.

  18. Recovery and regeneration of spent MHD seed material by the formate process

    DOEpatents

    Sheth, A.C.; Holt, J.K.; Rasnake, D.G.; Solomon, R.L.; Wilson, G.L.; Herrigel, H.R.

    1991-10-15

    The specification discloses a spent seed recovery and regeneration process for an MHD power plant employing an alkali metal salt seed material such as potassium salt wherein the spent potassium seed in the form of potassium sulfate is collected from the flue gas and reacted with calcium hydroxide and carbon monoxide in an aqueous solution to cause the formation of calcium sulfate and potassium formate. The pH of the solution is adjusted to suppress formation of formic acid and to promote precipitation of any dissolved calcium salts. The solution containing potassium formate is then employed to provide the potassium salt in the form of potassium formate or, optionally, by heating the potassium formate under oxidizing conditions to convert the potassium formate to potassium carbonate. 5 figures.

  19. Development of non-flammable lithium secondary battery with room-temperature ionic liquid electrolyte: Performance of electroplated Al film negative electrode

    NASA Astrophysics Data System (ADS)

    Ui, Koichi; Yamamoto, Keigo; Ishikawa, Kohei; Minami, Takuto; Takeuchi, Ken; Itagaki, Masayuki; Watanabe, Kunihiro; Koura, Nobuyuki

    The negative electrode performance of the electroplated Al film electrode in the LiCl saturated AlCl 3-1-ethyl-3-methylimizadolium chloride (EMIC) + SOCl 2 melt as the electrolyte for use in non-flammable lithium secondary batteries was evaluated. In the cyclic voltammogram of the electroplated Al film electrode in the melt, the oxidation and reduction waves corresponding to the electrochemical insertion/extraction reactions of the Li + ion were observed at 0-0.80 V vs. Li +/Li, which suggested that the electroplated Al film electrode operated well in the electrolyte. The almost flat potential profiles at about 0.40 V vs. Li +/Li on discharging were shown. The discharge capacity and charge-discharge efficiency was 236 mAh g -1 and 79.2% for the 1st cycle and it maintained 232 mAh g -1 and 77.9% after the 10th cycle. In addition, the initial charge-discharge efficiencies of the electroplated Al film electrode were higher than that of carbon electrodes. The main cathodic polarization reaction was the insertion of Li + ions, and side reactions hardly occurred due to the decomposition reaction of the melt because the Li content corresponding to the electricity was almost totally inserted into the film after charging.

  20. Manufacture of porous biodegradable polymer conduits by an extrusion process for guided tissue regeneration.

    PubMed

    Widmer, M S; Gupta, P K; Lu, L; Meszlenyi, R K; Evans, G R; Brandt, K; Savel, T; Gurlek, A; Patrick, C W; Mikos, A G

    1998-11-01

    We have fabricated porous, biodegradable tubular conduits for guided tissue regeneration using a combined solvent casting and extrusion technique. The biodegradable polymers used in this study were poly(DL-lactic-co-glycolic acid) (PLGA) and poly(L-lactic acid) (PLLA). A polymer/salt composite was first prepared by a solvent casting process. After drying, the composite was extruded to form a tubular construct. The salt particles in the construct were then leached out leaving a conduit with an open-pore structure. PLGA was studied as a model polymer to analyze the effects of salt weight fraction, salt particle size, and processing temperature on porosity and pore size of the extruded conduits. The porosity and pore size were found to increase with increasing salt weight fraction. Increasing the salt particle size increased the pore diameter but did not affect the porosity. High extrusion temperatures decreased the pore diameter without altering the porosity. Greater decrease in molecular weight was observed for conduits manufactured at higher temperatures. The mechanical properties of both PLGA and PLLA conduits were tested after degradation in vitro for up to 8 weeks. The modulus and failure strength of PLLA conduits were approximately 10 times higher than those of PLGA conduits. Failure strain was similar for both conduits. After degradation for 8 weeks, the molecular weights of the PLGA and PLLA conduits decreased to 38% and 43% of the initial values, respectively. However, both conduits maintained their shape and did not collapse. The PLGA also remained amorphous throughout the time course, while the crystallinity of PLLA increased from 5.2% to 11.5%. The potential of seeding the conduits with cells for transplantation or with biodegradable polymer microparticles for drug delivery was also tested with dyed microspheres. These porous tubular structures hold great promise for the regeneration of tissues which require tubular scaffolds such as peripheral nerve