Science.gov

Sample records for based hydrogen storage

  1. Hydrogen-based electrochemical energy storage

    DOEpatents

    Simpson, Lin Jay

    2013-08-06

    An energy storage device (100) providing high storage densities via hydrogen storage. The device (100) includes a counter electrode (110), a storage electrode (130), and an ion conducting membrane (120) positioned between the counter electrode (110) and the storage electrode (130). The counter electrode (110) is formed of one or more materials with an affinity for hydrogen and includes an exchange matrix for elements/materials selected from the non-noble materials that have an affinity for hydrogen. The storage electrode (130) is loaded with hydrogen such as atomic or mono-hydrogen that is adsorbed by a hydrogen storage material such that the hydrogen (132, 134) may be stored with low chemical bonding. The hydrogen storage material is typically formed of a lightweight material such as carbon or boron with a network of passage-ways or intercalants for storing and conducting mono-hydrogen, protons, or the like. The hydrogen storage material may store at least ten percent by weight hydrogen (132, 134) at ambient temperature and pressure.

  2. Amineborane Based Chemical Hydrogen Storage - Final Report

    SciTech Connect

    Sneddon, Larry G.

    2011-04-21

    The development of efficient and safe methods for hydrogen storage is a major hurdle that must be overcome to enable the use of hydrogen as an alternative energy carrier. The objectives of this project in the DOE Center of Excellence in Chemical Hydride Storage were both to develop new methods for on-demand, low temperature hydrogen release from chemical hydrides and to design high-conversion off-board methods for chemical hydride regeneration. Because of their reactive protic (N-H) and hydridic (B-H) hydrogens and high hydrogen contents, amineboranes such as ammonia borane, NH3BH3 (AB), 19.6-wt% H2, and ammonia triborane NH3B3H7 (AT), 17.7-wt% H2, were initially identified by the Center as promising, high-capacity chemical hydrogen storage materials with the potential to store and deliver molecular hydrogen through dehydrogenation and hydrolysis reactions. In collaboration with other Center partners, the Penn project focused both on new methods to induce amineborane H2-release and on new strategies for the regeneration the amineborane spent-fuel materials. The Penn approach to improving amineborane H2-release focused on the use of ionic liquids, base additives and metal catalysts to activate AB dehydrogenation and these studies successfully demonstrated that in ionic liquids the AB induction period that had been observed in the solid-state was eliminated and both the rate and extent of AB H2-release were significantly increased. These results have clearly shown that, while improvements are still necessary, many of these systems have the potential to achieve DOE hydrogen-storage goals. The high extent of their H2­-release, the tunability of both their H2 materials weight-percents and release rates, and their product control that is attained by either trapping or suppressing unwanted volatile side products, such as borazine, continue to make AB/ionic­-liquid based systems attractive candidates for chemical hydrogen storage applications. These studies also

  3. PNNL Development and Analysis of Material-Based Hydrogen Storage Systems for the Hydrogen Storage Engineering Center of Excellence

    SciTech Connect

    Brooks, Kriston P.; Alvine, Kyle J.; Johnson, Kenneth I.; Klymyshyn, Nicholas A.; Pires, Richard P.; Ronnebro, Ewa; Simmons, Kevin L.; Weimar, Mark R.; Westman, Matthew P.

    2016-02-29

    The Hydrogen Storage Engineering Center of Excellence is a team of universities, industrial corporations, and federal laboratories with the mandate to develop lower-pressure, materials-based, hydrogen storage systems for hydrogen fuel cell light-duty vehicles. Although not engaged in the development of new hydrogen storage materials themselves, it is an engineering center that addresses engineering challenges associated with the currently available hydrogen storage materials. Three material-based approaches to hydrogen storage are being researched: 1) chemical hydrogen storage materials 2) cryo-adsorbents, and 3) metal hydrides. As a member of this Center, Pacific Northwest National Laboratory (PNNL) has been involved in the design and evaluation of systems developed with each of these three hydrogen storage materials. This report is a compilation of the work performed by PNNL for this Center.

  4. Hydrogen Storage

    SciTech Connect

    2008-11-01

    This 2-page fact sheet provides a brief introduction to hydrogen storage technologies. Intended for a non-technical audience, it explains the different ways in which hydrogen can be stored, as well as the technical challenges and research goals for storing hydrogen on board a vehicle.

  5. Boron-Based Hydrogen Storage: Ternary Borides and Beyond

    SciTech Connect

    Vajo, John J.

    2016-04-28

    DOE continues to seek reversible solid-state hydrogen materials with hydrogen densities of ≥11 wt% and ≥80 g/L that can deliver hydrogen and be recharged at moderate temperatures (≤100 °C) and pressures (≤100 bar) enabling incorporation into hydrogen storage systems suitable for transportation applications. Boron-based hydrogen storage materials have the potential to meet the density requirements given boron’s low atomic weight, high chemical valance, and versatile chemistry. However, the rates of hydrogen exchange in boron-based compounds are thus far much too slow for practical applications. Although contributing to the high hydrogen densities, the high valance of boron also leads to slow rates of hydrogen exchange due to extensive boron-boron atom rearrangements during hydrogen cycling. This rearrangement often leads to multiple solid phases occurring over hydrogen release and recharge cycles. These phases must nucleate and react with each other across solid-solid phase boundaries leading to energy barriers that slow the rates of hydrogen exchange. This project sought to overcome the slow rates of hydrogen exchange in boron-based hydrogen storage materials by minimizing the number of solid phases and the boron atom rearrangement over a hydrogen release and recharge cycle. Two novel approaches were explored: 1) developing matched pairs of ternary borides and mixed-metal borohydrides that could exchange hydrogen with only one hydrogenated phase (the mixed-metal borohydride) and only one dehydrogenated phase (the ternary boride); and 2) developing boranes that could release hydrogen by being lithiated using lithium hydride with no boron-boron atom rearrangement.

  6. A Cassette Based System for Hydrogen Storage and Delivery

    SciTech Connect

    Britton Wayne E.

    2006-11-29

    A hydrogen storage system is described and evaluated. This is based upon a cassette, that is a container for managing hydrogen storage materials. The container is designed to be safe, modular, adaptable to different chemistries, inexpensive, and transportable. A second module receives the cassette and provides the necessary infrastructure to deliver hydrogen from the cassette according to enduser requirements. The modular concept has a number of advantages over approaches that are all in one stand alone systems. The advantages of a cassette based system are discussed, along with results from model and laboratory testing.

  7. Transition metal based borohydrides for hydrogen storage

    NASA Astrophysics Data System (ADS)

    Jayanthi, Chakram; Liu, Jianjun; Wei, Suhuai; Zhao, Yufeng

    2010-03-01

    Using ab-initio studies based on the density-functional theory, we have calculated binding energies per hydrogen molecule for decomposition reactions of transition metal borohydrides MHxB12H12 to MB12 structures, where M corresponds to Sc, Ti, or V. Depending on the valence of the transition metal, x can be 1, 2, or 3. Crystal structures considered for MB12 included both hypothetical and those found in the international crystallographic structural database. On the other hand, the crystal structure considered for MHxB12H12 belongs to C2/c (space group 15) structure as reported in a previous study [V. Ozolins et al. JACS, 131, 230 (2009)]. Among the structures investigated, Titanium-based metal borohydride structure has the lowest binding energy per hydrogen molecule relative to the cubic TiB12 structure (˜0.37 eV/H2). Our finding should be contrasted with the binding energy/H2 for simple metal based borohydrides (e.g., CaB12H12 ), which has a value of ˜ 1.5 eV/H2, suggesting that transition metals play a significant role in lowering the H2 binding energy in borohydrides.

  8. Hydrogen Research for Spaceport and Space-Based Applications: Hydrogen Production, Storage, and Transport. Part 3

    NASA Technical Reports Server (NTRS)

    Anderson, Tim; Balaban, Canan

    2008-01-01

    The activities presented are a broad based approach to advancing key hydrogen related technologies in areas such as fuel cells, hydrogen production, and distributed sensors for hydrogen-leak detection, laser instrumentation for hydrogen-leak detection, and cryogenic transport and storage. Presented are the results from research projects, education and outreach activities, system and trade studies. The work will aid in advancing the state-of-the-art for several critical technologies related to the implementation of a hydrogen infrastructure. Activities conducted are relevant to a number of propulsion and power systems for terrestrial, aeronautics and aerospace applications. Hydrogen storage and in-space hydrogen transport research focused on developing and verifying design concepts for efficient, safe, lightweight liquid hydrogen cryogenic storage systems. Research into hydrogen production had a specific goal of further advancing proton conducting membrane technology in the laboratory at a larger scale. System and process trade studies evaluated the proton conducting membrane technology, specifically, scale-up issues.

  9. Mg-based compounds for hydrogen and energy storage

    NASA Astrophysics Data System (ADS)

    Crivello, J.-C.; Denys, R. V.; Dornheim, M.; Felderhoff, M.; Grant, D. M.; Huot, J.; Jensen, T. R.; de Jongh, P.; Latroche, M.; Walker, G. S.; Webb, C. J.; Yartys, V. A.

    2016-02-01

    Magnesium-based alloys attract significant interest as cost-efficient hydrogen storage materials allowing the combination of high gravimetric storage capacity of hydrogen with fast rates of hydrogen uptake and release and pronounced destabilization of the metal-hydrogen bonding in comparison with binary Mg-H systems. In this review, various groups of magnesium compounds are considered, including (1) RE-Mg-Ni hydrides (RE = La, Pr, Nd); (2) Mg alloys with p-elements (X = Si, Ge, Sn, and Al); and (3) magnesium alloys with d-elements (Ti, Fe, Co, Ni, Cu, Zn, Pd). The hydrogenation-disproportionation-desorption-recombination process in the Mg-based alloys (LaMg12, LaMg11Ni) and unusually high-pressure hydrides synthesized at pressures exceeding 100 MPa (MgNi2H3) and stabilized by Ni-H bonding are also discussed. The paper reviews interrelations between the properties of the Mg-based hydrides and p- T conditions of the metal-hydrogen interactions, chemical composition of the initial alloys, their crystal structures, and microstructural state.

  10. Mitigation technologies for hydrogen storage systems based on reactive solids.

    SciTech Connect

    Kanouff, Michael P.; Dedrick, Daniel E.; Khalil, Y. F.; Pratt, Joseph William; Reeder, Craig; Cordaro, Joseph Gabriel

    2010-11-01

    This paper describes mitigation technologies that are intended to enable the deployment of advanced hydrogen storage technologies for early market and automotive fuel cell applications. Solid State hydrogen storage materials provide an opportunity for a dramatic increase in gravimetric and volumetric energy storage density. Systems and technologies based on the advanced materials have been developed and demonstrated within the laboratory [1,2], and in some cases, integrated with fuel cell systems. The R&D community will continue to develop these technologies for an ever increasing market of fuel cell technologies, including, forklift, light-cart, APU, and automotive systems. Solid state hydrogen storage materials are designed and developed to readily release, and in some cases, react with diatomic hydrogen. This favorable behavior is often accomplished with morphology design (high surface area), catalytic additives (titanium for example), and high purity metals (such as aluminum, Lanthanum, or alkali metals). These favorable hydrogen reaction characteristics often have a related, yet less-desirable effect: sensitivity and reactivity during exposure to ambient contamination and out-of-design environmental conditions. Accident scenarios resulting in this less-favorable reaction behavior must also be managed by the system developer to enable technology deployment and market acceptance. Two important accident scenarios are identified through hazards and risk analysis methods. The first involves a breach in plumbing or tank resulting from a collision. The possible consequence of this scenario is analyzed though experimentally based chemical kinetic and transport modeling of metal hydride beds. An advancing reaction front between the metal hydride and ambient air is observed to proceed throughout the bed. This exothermic reaction front can result in loss of structural integrity of the containing vessel and lead to un-favorable overheating events. The second important

  11. ACCEPTABILITY ENVELOPE FOR METAL HYDRIDE-BASED HYDROGEN STORAGE SYSTEMS

    SciTech Connect

    Hardy, B.; Corgnale, C.; Tamburello, D.; Garrison, S.; Anton, D.

    2011-07-18

    The design and evaluation of media based hydrogen storage systems requires the use of detailed numerical models and experimental studies, with significant amount of time and monetary investment. Thus a scoping tool, referred to as the Acceptability Envelope, was developed to screen preliminary candidate media and storage vessel designs, identifying the range of chemical, physical and geometrical parameters for the coupled media and storage vessel system that allow it to meet performance targets. The model which underpins the analysis allows simplifying the storage system, thus resulting in one input-one output scheme, by grouping of selected quantities. Two cases have been analyzed and results are presented here. In the first application the DOE technical targets (Year 2010, Year 2015 and Ultimate) are used to determine the range of parameters required for the metal hydride media and storage vessel. In the second case the most promising metal hydrides available are compared, highlighting the potential of storage systems, utilizing them, to achieve 40% of the 2010 DOE technical target. Results show that systems based on Li-Mg media have the best potential to attain these performance targets.

  12. Electron Charged Graphite-based Hydrogen Storage Material

    SciTech Connect

    Dr. Chinbay Q. Fan R&D Manager Office of Technology and Innovations Phone: 847 768 0812

    2012-03-14

    The electron-charge effects have been demonstrated to enhance hydrogen storage capacity using materials which have inherent hydrogen storage capacities. A charge control agent (CCA) or a charge transfer agent (CTA) was applied to the hydrogen storage material to reduce internal discharge between particles in a Sievert volumetric test device. GTI has tested the device under (1) electrostatic charge mode; (2) ultra-capacitor mode; and (3) metal-hydride mode. GTI has also analyzed the charge distribution on storage materials. The charge control agent and charge transfer agent are needed to prevent internal charge leaks so that the hydrogen atoms can stay on the storage material. GTI has analyzed the hydrogen fueling tank structure, which contains an air or liquid heat exchange framework. The cooling structure is needed for hydrogen fueling/releasing. We found that the cooling structure could be used as electron-charged electrodes, which will exhibit a very uniform charge distribution (because the cooling system needs to remove heat uniformly). Therefore, the electron-charge concept does not have any burden of cost and weight for the hydrogen storage tank system. The energy consumption for the electron-charge enhancement method is quite low or omitted for electrostatic mode and ultra-capacitor mode in comparison of other hydrogen storage methods; however, it could be high for the battery mode.

  13. An experimental study of ammonia borane based hydrogen storage systems

    NASA Astrophysics Data System (ADS)

    Deshpande, Kedaresh A.

    2011-12-01

    Hydrogen is a promising fuel for the future, capable of meeting the demands of energy storage and low pollutant emission. Chemical hydrides are potential candidates for chemical hydrogen storage, especially for automobile applications. Ammonia borane (AB) is a chemical hydride being investigated widely for its potential to realize the hydrogen economy. In this work, the yield of hydrogen obtained during neat AB thermolysis was quantified using two reactor systems. First, an oil bath heated glass reactor system was used with AB batches of 0.13 gram (+/- 0.001 gram). The rates of hydrogen generation were measured. Based on these experimental data, an electrically heated steel reactor system was designed and constructed to handle up to 2 grams of AB per batch. A majority of components were made of stainless-steel. The system consisted of an AB reservoir and feeder, a heated reactor, a gas processing unit and a system control and monitoring unit. An electronic data acquisition system was used to record experimental data. The performance of the steel reactor system was evaluated experimentally through batch reactions of 30 minutes each, for reaction temperatures in the range from 373 K to 430 K. The experimental data showed exothermic decomposition of AB accompanied by rapid generation of hydrogen during the initial period of the reaction. 90% of the hydrogen was generated during the initial 120 seconds after addition of AB to the reactor. At 430 K, the reaction produced 12 wt.% of hydrogen. The heat diffusion in the reactor system and the process of exothermic decomposition of AB were coupled in a two-dimensional model. Neat AB thermolysis was modeled as a global first order reactions based on Arrhenius theory. The values of equation constants were derived from curve fit of experimental data. The pre-exponential constant and the activation energy were estimated to be 4 s-1 (+/- 0.4 s-1) and 13000 J mol -1 s-1 (+/- 1050 J mol-1 s -1) respectively. The model was solved

  14. Nanostructured and Nanocomposite Light-Metal Based Compounds For Hydrogen Storage

    DTIC Science & Technology

    2003-09-01

    NANOSTRUCTURED AND NANOCOMPOSITE LIGHT-METAL BASED COMPOUNDS FOR HYDROGEN STORAGE R.A. Varin1), L.Guo1), S. Li1*), Ch. Chiu1), A. Calka2) 1...DATES COVERED - 4. TITLE AND SUBTITLE Nanostructured And Nanocomposite Light-Metal Based Compounds For Hydrogen Storage 5a. CONTRACT NUMBER...foundation of the next industrial revolution in the application of hydrogen as the fuel of the future. HYDROGEN STORAGE FOR PROTON MEMBRANE

  15. EMR modelling of a hydrogen-based electrical energy storage

    NASA Astrophysics Data System (ADS)

    Agbli, K. S.; Hissel, D.; Péra, M.-C.; Doumbia, I.

    2011-05-01

    This paper deals with multi-physics modelling of the stationary system. This modelling is the first step to reach the fuel cell system dimensioning aim pursued. Besides this modelling approach based on the stationary energetic system, the novelty in this paper is both the new approach of the photovoltaic EMR modelling and the EMR of the hydrogen storage process. The granular modelling approach is used to model each component of the system. Considering a stand alone PEM fuel cell system, hydrogen is expected to be produced and stored on the spot from renewable energy (photovoltaic) in order to satisfy the fuel availability. In fact, to develop a generic and modular model, energetic macroscopic representation (EMR) is used as graphical modelling tool. Allowing to be easily grasped by the experts even not necessarily gotten used to the modelling formalism, EMR is helpful to model the multi-domains energetic chain. The solar energy through solar module is converted in electrical energy; part of this energy is transformed in chemical energy (hydrogen) thanks to an electrolyser. Then the hydrogen is compressed into a tank across a storage system. The latter part of the solar module energy is stored as electrical energy within supercapacitor or lead-acid battery. Using the modularity feature of the EMR, the whole system is modelled entity by entity; afterwards by putting them together the overall system has been reconstructed. According to the scale effect of the system entities, some simulation and/or experimental results are given. Given to the different aims which are pursued in the sustainable energy framework like prediction, control and optimisation, EMR modelling approach is a reliable option for the energy management in real time of energetic system in macroscopic point of view.

  16. Carborane-Based Metal-Organic Framework with High Methane and Hydrogen Storage Capacities

    DTIC Science & Technology

    2013-01-01

    REPORT Carborane-Based Metal –Organic Framework with High Methane and Hydrogen Storage Capacities 14. ABSTRACT 16. SECURITY CLASSIFICATION OF: A Cu...Carborane-Based Metal –Organic Framework with High Methane and Hydrogen Storage Capacities Report Title ABSTRACT A Cu?carborane-based metal ?organic...Based Metal −Organic Framework with High Methane and Hydrogen Storage Capacities Robert D. Kennedy,† Vaiva Krungleviciute,‡,§ Daniel J. Clingerman,† Joseph

  17. Highly efficient hydrogen storage system based on ammonium bicarbonate/formate redox equilibrium over palladium nanocatalysts.

    PubMed

    Su, Ji; Yang, Lisha; Lu, Mi; Lin, Hongfei

    2015-03-01

    A highly efficient, reversible hydrogen storage-evolution process has been developed based on the ammonium bicarbonate/formate redox equilibrium over the same carbon-supported palladium nanocatalyst. This heterogeneously catalyzed hydrogen storage system is comparable to the counterpart homogeneous systems and has shown fast reaction kinetics of both the hydrogenation of ammonium bicarbonate and the dehydrogenation of ammonium formate under mild operating conditions. By adjusting temperature and pressure, the extent of hydrogen storage and evolution can be well controlled in the same catalytic system. Moreover, the hydrogen storage system based on aqueous-phase ammonium formate is advantageous owing to its high volumetric energy density.

  18. The development of a fullerene based hydrogen storage system

    SciTech Connect

    Brosha, E.L.; Davey, J.R.; Garzon, F.H.; Gottesfeld, S.

    1998-11-01

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). The project objective was to evaluate hydrogen uptake by fullerene substrates and to probe the potential of the hydrogen/fullerene system for hydrogen fuel storage. As part of this project, the authors have completed and tested a fully automated, computer controlled system for measuring hydrogen uptake that is capable of handling both a vacuum of 1 x 10{sup -6} torr and pressures greater than 200 bars. The authors have first established conditions for significant uptake of hydrogen by fullerenes. Subsequently, hydrogenation and dehydrogenation of pure and catalyst-doped C60 was further studied to probe suitability for hydrogen storage applications. C60 {center_dot} H18.7 was prepared at 100 bar H2 and 400 C, corresponding to hydrogen uptake of 2.6 wt%. Dehydrogenation of C60 {center_dot} H18.7 was studied using thermogravimetric and powder x-ray diffraction analysis. The C60 {center_dot} H18.7 molecule was found to be stable up to 430 C in Ar, at which point the release of hydrogen took place simultaneously with the collapse of the fullerene structure. X-ray diffraction analysis performed on C60 {center_dot} H18.7 samples dehydrogenated at 454 C, 475 C, and 600 C showed an increasing volume fraction of amorphous material due to randomly oriented, single-layer graphine sheets. Evolved gas analysis using gas chromatography and mass spectroscopy confirmed the presence of both H{sub 2} and methane upon dehydrogenation, indicating decomposition of the fullerene. The remaining carbon could not be re-hydrogenated. These results provide the first complete evidence for the irreversible nature of fullerene hydrogenation and for limitations imposed on the hydrogenation/dehydrogenation cycle by the limited thermal stability of the molecular crystal of fullerene.

  19. Mg-based nanocomposites with high capacity and fast kinetics for hydrogen storage.

    PubMed

    Yao, Xiangdong; Wu, Chengzhang; Du, Aijun; Lu, Gao Qing; Cheng, Huiming; Smith, Sean C; Zou, Jin; He, Yinghe

    2006-06-22

    Magnesium and its alloys have shown a great potential in effective hydrogen storage due to their advantages of high volumetric/gravimetric hydrogen storage capacity and low cost. However, the use of these materials in fuel cells for automotive applications at the present time is limited by high hydrogenation temperature and sluggish sorption kinetics. This paper presents the recent results of design and development of magnesium-based nanocomposites demonstrating the catalytic effects of carbon nanotubes and transition metals on hydrogen adsorption in these materials. The results are promising for the application of magnesium materials for hydrogen storage, with significantly reduced absorption temperatures and enhanced ab/desorption kinetics. High level Density Functional Theory calculations support the analysis of the hydrogenation mechanisms by revealing the detailed atomic and molecular interactions that underpin the catalytic roles of incorporated carbon and titanium, providing clear guidance for further design and development of such materials with better hydrogen storage properties.

  20. Anisotropic storage medium development in a full-scale, sodium alanate-based, hydrogen storage system

    DOE PAGES

    Jorgensen, Scott W.; Johnson, Terry A.; Payzant, E. Andrew; ...

    2016-06-11

    Deuterium desorption in an automotive-scale hydrogen storage tube was studied in-situ using neutron diffraction. Gradients in the concentration of the various alanate phases were observed along the length of the tube but no significant radial anisotropy was present. In addition, neutron radiography and computed tomography showed large scale cracks and density fluctuations, confirming the presence of these structures in an undisturbed storage system. These results demonstrate that large scale storage structures are not uniform even after many absorption/desorption cycles and that movement of gaseous hydrogen cannot be properly modeled by a simple porous bed model. In addition, the evidence indicatesmore » that there is slow transformation of species at one end of the tube indicating loss of catalyst functionality. These observations explain the unusually fast movement of hydrogen in a full scale system and shows that loss of capacity is not occurring uniformly in this type of hydrogen-storage system.« less

  1. Anisotropic storage medium development in a full-scale, sodium alanate-based, hydrogen storage system

    SciTech Connect

    Jorgensen, Scott W.; Johnson, Terry A.; Payzant, E. Andrew; Bilheux, Hassina Z.

    2016-06-11

    Deuterium desorption in an automotive-scale hydrogen storage tube was studied in-situ using neutron diffraction. Gradients in the concentration of the various alanate phases were observed along the length of the tube but no significant radial anisotropy was present. In addition, neutron radiography and computed tomography showed large scale cracks and density fluctuations, confirming the presence of these structures in an undisturbed storage system. These results demonstrate that large scale storage structures are not uniform even after many absorption/desorption cycles and that movement of gaseous hydrogen cannot be properly modeled by a simple porous bed model. In addition, the evidence indicates that there is slow transformation of species at one end of the tube indicating loss of catalyst functionality. These observations explain the unusually fast movement of hydrogen in a full scale system and shows that loss of capacity is not occurring uniformly in this type of hydrogen-storage system.

  2. Anisotropic storage medium development in a full-scale, sodium alanate-based, hydrogen storage system

    SciTech Connect

    Jorgensen, Scott W.; Johnson, Terry A.; Payzant, E. Andrew; Bilheux, Hassina Z.

    2016-06-11

    Deuterium desorption in an automotive-scale hydrogen storage tube was studied in-situ using neutron diffraction. Gradients in the concentration of the various alanate phases were observed along the length of the tube but no significant radial anisotropy was present. In addition, neutron radiography and computed tomography showed large scale cracks and density fluctuations, confirming the presence of these structures in an undisturbed storage system. These results demonstrate that large scale storage structures are not uniform even after many absorption/desorption cycles and that movement of gaseous hydrogen cannot be properly modeled by a simple porous bed model. In addition, the evidence indicates that there is slow transformation of species at one end of the tube indicating loss of catalyst functionality. These observations explain the unusually fast movement of hydrogen in a full scale system and shows that loss of capacity is not occurring uniformly in this type of hydrogen-storage system.

  3. Challenges in hydrogen storage

    NASA Astrophysics Data System (ADS)

    Schüth, F.

    2009-09-01

    Hydrogen is one possible medium for energy storage and transportation in an era beyond oil. Hydrogen appears to be especially promising in connection with electricity generation in polymer electrolyte membrane (PEM) fuel cells in cars. However, before such technologies can be implemented on a larger scale, satisfactory solutions for on-board storage of hydrogen are required. This is a difficult task due to the low volumetric and gravimetric storage density on a systems level which can be achieved so far. Possibilities include cryogenic storage as liquid hydrogen, high pressure storage at 70 MPa, (cryo)adsorptive storage, or various chemical methods of binding and releasing hydrogen. This survey discusses the different options and the associated advantages and disadvantages.

  4. Ultrafine hydrogen storage powders

    DOEpatents

    Anderson, Iver E.; Ellis, Timothy W.; Pecharsky, Vitalij K.; Ting, Jason; Terpstra, Robert; Bowman, Robert C.; Witham, Charles K.; Fultz, Brent T.; Bugga, Ratnakumar V.

    2000-06-13

    A method of making hydrogen storage powder resistant to fracture in service involves forming a melt having the appropriate composition for the hydrogen storage material, such, for example, LaNi.sub.5 and other AB.sub.5 type materials and AB.sub.5+x materials, where x is from about -2.5 to about +2.5, including x=0, and the melt is gas atomized under conditions of melt temperature and atomizing gas pressure to form generally spherical powder particles. The hydrogen storage powder exhibits improved chemcial homogeneity as a result of rapid solidfication from the melt and small particle size that is more resistant to microcracking during hydrogen absorption/desorption cycling. A hydrogen storage component, such as an electrode for a battery or electrochemical fuel cell, made from the gas atomized hydrogen storage material is resistant to hydrogen degradation upon hydrogen absorption/desorption that occurs for example, during charging/discharging of a battery. Such hydrogen storage components can be made by consolidating and optionally sintering the gas atomized hydrogen storage powder or alternately by shaping the gas atomized powder and a suitable binder to a desired configuration in a mold or die.

  5. High Density Hydrogen Storage System Demonstration Using NaAlH4 Based Complex Compound Hydrides

    SciTech Connect

    Daniel A. Mosher; Xia Tang; Ronald J. Brown; Sarah Arsenault; Salvatore Saitta; Bruce L. Laube; Robert H. Dold; Donald L. Anton

    2007-07-27

    This final report describes the motivations, activities and results of the hydrogen storage independent project "High Density Hydrogen Storage System Demonstration Using NaAlH4 Based Complex Compound Hydrides" performed by the United Technologies Research Center under the Department of Energy Hydrogen Program, contract # DE-FC36-02AL67610. The objectives of the project were to identify and address the key systems technologies associated with applying complex hydride materials, particularly ones which differ from those for conventional metal hydride based storage. This involved the design, fabrication and testing of two prototype systems based on the hydrogen storage material NaAlH4. Safety testing, catalysis studies, heat exchanger optimization, reaction kinetics modeling, thermochemical finite element analysis, powder densification development and material neutralization were elements included in the effort.

  6. New insights into designing metallacarborane based room temperature hydrogen storage media

    SciTech Connect

    Bora, Pankaj Lochan; Singh, Abhishek K.

    2013-10-28

    Metallacarboranes are promising towards realizing room temperature hydrogen storage media because of the presence of both transition metal and carbon atoms. In metallacarborane clusters, the transition metal adsorbs hydrogen molecules and carbon can link these clusters to form metal organic framework, which can serve as a complete storage medium. Using first principles density functional calculations, we chalk out the underlying principles of designing an efficient metallacarborane based hydrogen storage media. The storage capacity of hydrogen depends upon the number of available transition metal d-orbitals, number of carbons, and dopant atoms in the cluster. These factors control the amount of charge transfer from metal to the cluster, thereby affecting the number of adsorbed hydrogen molecules. This correlation between the charge transfer and storage capacity is general in nature, and can be applied to designing efficient hydrogen storage systems. Following this strategy, a search for the best metallacarborane was carried out in which Sc based monocarborane was found to be the most promising H{sub 2} sorbent material with a 9 wt.% of reversible storage at ambient pressure and temperature.

  7. New insights into designing metallacarborane based room temperature hydrogen storage media.

    PubMed

    Bora, Pankaj Lochan; Singh, Abhishek K

    2013-10-28

    Metallacarboranes are promising towards realizing room temperature hydrogen storage media because of the presence of both transition metal and carbon atoms. In metallacarborane clusters, the transition metal adsorbs hydrogen molecules and carbon can link these clusters to form metal organic framework, which can serve as a complete storage medium. Using first principles density functional calculations, we chalk out the underlying principles of designing an efficient metallacarborane based hydrogen storage media. The storage capacity of hydrogen depends upon the number of available transition metal d-orbitals, number of carbons, and dopant atoms in the cluster. These factors control the amount of charge transfer from metal to the cluster, thereby affecting the number of adsorbed hydrogen molecules. This correlation between the charge transfer and storage capacity is general in nature, and can be applied to designing efficient hydrogen storage systems. Following this strategy, a search for the best metallacarborane was carried out in which Sc based monocarborane was found to be the most promising H2 sorbent material with a 9 wt.% of reversible storage at ambient pressure and temperature.

  8. Electrochemical hydrogen Storage Systems

    SciTech Connect

    Dr. Digby Macdonald

    2010-08-09

    As the global need for energy increases, scientists and engineers have found a possible solution by using hydrogen to power our world. Although hydrogen can be combusted as a fuel, it is considered an energy carrier for use in fuel cells wherein it is consumed (oxidized) without the production of greenhouse gases and produces electrical energy with high efficiency. Chemical storage of hydrogen involves release of hydrogen in a controlled manner from materials in which the hydrogen is covalently bound. Sodium borohydride and aminoborane are two materials given consideration as chemical hydrogen storage materials by the US Department of Energy. A very significant barrier to adoption of these materials as hydrogen carriers is their regeneration from 'spent fuel,' i.e., the material remaining after discharge of hydrogen. The U.S. Department of Energy (DOE) formed a Center of Excellence for Chemical Hydrogen Storage, and this work stems from that project. The DOE has identified boron hydrides as being the main compounds of interest as hydrogen storage materials. The various boron hydrides are then oxidized to release their hydrogen, thereby forming a 'spent fuel' in the form of a lower boron hydride or even a boron oxide. The ultimate goal of this project is to take the oxidized boron hydrides as the spent fuel and hydrogenate them back to their original form so they can be used again as a fuel. Thus this research is essentially a boron hydride recycling project. In this report, research directed at regeneration of sodium borohydride and aminoborane is described. For sodium borohydride, electrochemical reduction of boric acid and sodium metaborate (representing spent fuel) in alkaline, aqueous solution has been investigated. Similarly to literature reports (primarily patents), a variety of cathode materials were tried in these experiments. Additionally, approaches directed at overcoming electrostatic repulsion of borate anion from the cathode, not described in the

  9. Thermodynamic Tuning of Mg-Based Hydrogen Storage Alloys: A Review

    PubMed Central

    Zhu, Min; Lu, Yanshan; Ouyang, Liuzhang; Wang, Hui

    2013-01-01

    Mg-based hydrides are one of the most promising hydrogen storage materials because of their relatively high storage capacity, abundance, and low cost. However, slow kinetics and stable thermodynamics hinder their practical application. In contrast to the substantial progress in the enhancement of the hydrogenation/dehydrogenation kinetics, thermodynamic tuning is still a great challenge for Mg-based alloys. At present, the main strategies to alter the thermodynamics of Mg/MgH2 are alloying, nanostructuring, and changing the reaction pathway. Using these approaches, thermodynamic tuning has been achieved to some extent, but it is still far from that required for practical application. In this article, we summarize the advantages and disadvantages of these strategies. Based on the current progress, finding reversible systems with high hydrogen capacity and effectively tailored reaction enthalpy offers a promising route for tuning the thermodynamics of Mg-based hydrogen storage alloys. PMID:28788353

  10. Combining photocatalytic hydrogen generation and capsule storage in graphene based sandwich structures

    NASA Astrophysics Data System (ADS)

    Yang, Li; Li, Xiyu; Zhang, Guozhen; Cui, Peng; Wang, Xijun; Jiang, Xiang; Zhao, Jin; Luo, Yi; Jiang, Jun

    2017-07-01

    The challenge of safe hydrogen storage has limited the practical application of solar-driven photocatalytic water splitting. It is hard to isolate hydrogen from oxygen products during water splitting to avoid unwanted reverse reaction or explosion. Here we propose a multi-layer structure where a carbon nitride is sandwiched between two graphene sheets modified by different functional groups. First-principles simulations demonstrate that such a system can harvest light and deliver photo-generated holes to the outer graphene-based sheets for water splitting and proton generation. Driven by electrostatic attraction, protons penetrate through graphene to react with electrons on the inner carbon nitride to generate hydrogen molecule. The produced hydrogen is completely isolated and stored with a high-density level within the sandwich, as no molecules could migrate through graphene. The ability of integrating photocatalytic hydrogen generation and safe capsule storage has made the sandwich system an exciting candidate for realistic solar and hydrogen energy utilization.

  11. Combining photocatalytic hydrogen generation and capsule storage in graphene based sandwich structures.

    PubMed

    Yang, Li; Li, Xiyu; Zhang, Guozhen; Cui, Peng; Wang, Xijun; Jiang, Xiang; Zhao, Jin; Luo, Yi; Jiang, Jun

    2017-07-06

    The challenge of safe hydrogen storage has limited the practical application of solar-driven photocatalytic water splitting. It is hard to isolate hydrogen from oxygen products during water splitting to avoid unwanted reverse reaction or explosion. Here we propose a multi-layer structure where a carbon nitride is sandwiched between two graphene sheets modified by different functional groups. First-principles simulations demonstrate that such a system can harvest light and deliver photo-generated holes to the outer graphene-based sheets for water splitting and proton generation. Driven by electrostatic attraction, protons penetrate through graphene to react with electrons on the inner carbon nitride to generate hydrogen molecule. The produced hydrogen is completely isolated and stored with a high-density level within the sandwich, as no molecules could migrate through graphene. The ability of integrating photocatalytic hydrogen generation and safe capsule storage has made the sandwich system an exciting candidate for realistic solar and hydrogen energy utilization.

  12. Carbon material for hydrogen storage

    SciTech Connect

    Bourlinos, Athanasios; Steriotis, Theodore; Stubos, Athanasios; Miller, Michael A

    2016-09-13

    The present invention relates to carbon based materials that are employed for hydrogen storage applications. The material may be described as the pyrolysis product of a molecular precursor such as a cyclic quinone compound. The pyrolysis product may then be combined with selected transition metal atoms which may be in nanoparticulate form, where the metals may be dispersed on the material surface. Such product may then provide for the reversible storage of hydrogen. The metallic nanoparticles may also be combined with a second metal as an alloy to further improve hydrogen storage performance.

  13. Hydrogen storage in carbon nanotubes.

    PubMed

    Hirscher, M; Becher, M

    2003-01-01

    The article gives a comprehensive overview of hydrogen storage in carbon nanostructures, including experimental results and theoretical calculations. Soon after the discovery of carbon nanotubes in 1991, different research groups succeeded in filling carbon nanotubes with some elements, and, therefore, the question arose of filling carbon nanotubes with hydrogen by possibly using new effects such as nano-capillarity. Subsequently, very promising experiments claiming high hydrogen storage capacities in different carbon nanostructures initiated enormous research activity. Hydrogen storage capacities have been reported that exceed the benchmark for automotive application of 6.5 wt% set by the U.S. Department of Energy. However, the experimental data obtained with different methods for various carbon nanostructures show an extreme scatter. Classical calculations based on physisorption of hydrogen molecules could not explain the high storage capacities measured at ambient temperature, and, assuming chemisorption of hydrogen atoms, hydrogen release requires temperatures too high for technical applications. Up to now, only a few calculations and experiments indicate the possibility of an intermediate binding energy. Recently, serious doubt has arisen in relation to several key experiments, causing considerable controversy. Furthermore, high hydrogen storage capacities measured for carbon nanofibers did not survive cross-checking in different laboratories. Therefore, in light of today's knowledge, it is becoming less likely that at moderate pressures around room temperature carbon nanostructures can store the amount of hydrogen required for automotive applications.

  14. Hydrogen storage compositions

    DOEpatents

    Li, Wen; Vajo, John J.; Cumberland, Robert W.; Liu, Ping

    2011-04-19

    Compositions for hydrogen storage and methods of making such compositions employ an alloy that exhibits reversible formation/deformation of BH.sub.4.sup.- anions. The composition includes a ternary alloy including magnesium, boron and a metal and a metal hydride. The ternary alloy and the metal hydride are present in an amount sufficient to render the composition capable of hydrogen storage. The molar ratio of the metal to magnesium and boron in the alloy is such that the alloy exhibits reversible formation/deformation of BH.sub.4.sup.- anions. The hydrogen storage composition is prepared by combining magnesium, boron and a metal to prepare a ternary alloy and combining the ternary alloy with a metal hydride to form the hydrogen storage composition.

  15. High-Capacity Hydrogen-Based Green-Energy Storage Solutions For The Grid Balancing

    NASA Astrophysics Data System (ADS)

    D'Errico, F.; Screnci, A.

    One of the current main challenges in green-power storage and smart grids is the lack of effective solutions for accommodating the unbalance between renewable energy sources, that offer intermittent electricity supply, and a variable electricity demand. Energy management systems have to be foreseen for the near future, while they still represent a major challenge. Integrating intermittent renewable energy sources, by safe and cost-effective energy storage systems based on solid state hydrogen is today achievable thanks to recently some technology breakthroughs. Optimized solid storage method made of magnesium-based hydrides guarantees a very rapid absorption and desorption kinetics. Coupled with electrolyzer technology, high-capacity storage of green-hydrogen is therefore practicable. Besides these aspects, magnesium has been emerging as environmentally friend energy storage method to sustain integration, monitoring and control of large quantity of GWh from high capacity renewable generation in the EU.

  16. High-Capacity Hydrogen-Based Green-Energy Storage Solutions for the Grid Balancing

    NASA Astrophysics Data System (ADS)

    D'Errico, F.; Screnci, A.

    One of the current main challenges in green-power storage and smart grids is the lack of effective solutions for accommodating the unbalance between renewable energy sources, that offer intermittent electricity supply, and a variable electricity demand. Energy management systems have to be foreseen for the near future, while they still represent a major challenge. Integrating intermittent renewable energy sources, by safe and cost-effective energy storage systems based on solid state hydrogen is today achievable thanks to recently some technology breakthroughs. Optimized solid storage method made of magnesium-based hydrides guarantees a very rapid absorption and desorption kinetics. Coupled with electrolyzer technology, high-capacity storage of green-hydrogen is therefore practicable. Besides these aspects, magnesium has been emerging as environmentally friend energy storage method to sustain integration, monitoring and control of large quantity of GWh from high capacity renewable generation in the EU.

  17. Synthesis and characterization of light-metal-based hydrides for hydrogen storage materials

    NASA Astrophysics Data System (ADS)

    Choi, Young Joon

    In the past few years, research and development on the use of hydrogen as a fuel for various applications have gathered momentum in response to the demand for cleaner fuels and substitutes to fossil fuels. The use of hydrogen for automobiles, one of the most important applications of hydrogen fuel, requires an on-board hydrogen storage system that can be regenerated on-board or off-board. However, one of the key obstacles to this application is that current available storage technologies do not meet the capacity and efficiency requirements for achieving the commercial viability. In this study, two solid-state hydrogen storage systems, i.e. Mg-Ti-H and Li-Al-B-H, are investigated. Among a variety of MgH2/TiH2 ratios and milling conditions, the 10MgH2/TiH2 sample milled in a dual-planetary high-energy mill for 4 hours under 15 MPa hydrogen pressure were found to be the optimal materials, displaying a substantially reduced activation energy and enthalpy change for MgH2 dehydrogenation. PCT analysis demonstrated that the system showed excellent cycle stability attributed to the inhibition of coarsening by TiH2. Lithium borohydride (LiBH4) is one of the promising candidates as a superior hydrogen storage because of its high theoretical storage capacity (18.5 wt.%). In this work, the promising hydrogen storage properties of combined systems of Li3AlH6/LiBH4 and Al/LiBH 4, exhibiting the favorable formation of AlB2 during dehydrogenation, were presented based on TGA and XRD analyses. Additionally, the characterization of the intermediate and final products of the dehydrogenation and rehydrogenation of the above systems by solid-state NMR analyses were presented. This has verified and further clarified the paths and intermediate products of the reversible hydrogen release and uptake by the mixtures.

  18. Hydrogen Storage and Transfer

    DTIC Science & Technology

    1975-08-25

    pressurization, chilldown of transfer lines, heat leak through surfaces , liquid trapped in the transfer line (and eventually drained at the end of each...storage of liquid hydrogen are: vacuum with a liquid-nitrogen shield; evacuated foams; evacuated perlite ; ana evacuated multi-layer "super-insulations...example, the 26,000 gal. storage tank frequently employed for rail shipments, contains a 15-inch thickness of perlite insulation, and the hydrogen

  19. Thermal management of the adsorption-based vessel for hydrogeneous gas storage

    NASA Astrophysics Data System (ADS)

    Vasiliev, L. L.; Kanonchik, L. E.; Babenko, V. A.

    2012-09-01

    Thermal management is a design bottleneck in the creation of rational gas storage sorption systems. Inefficient heat transfer in a sorption bed is connected with a relatively low thermal conductivity (0.1-0.5 W/(mṡK)) and an appreciable sorption heat of activated gas storage materials. This work is devoted to the development of a thermally regulated onboard system of hydrogenous gas (methane and hydrogen) storage with the use of novel carbon sorbents. A hydrogenous gas storage system based on combined gas adsorption and compression at moderate pressures (3-6 MPa) and low temperatures (from the temperature of liquid nitrogen of about 77 K to a temperature of 273 K) is suggested.

  20. Slurry-based chemical hydrogen storage systems for automotive fuel cell applications

    NASA Astrophysics Data System (ADS)

    Brooks, Kriston P.; Semelsberger, Troy A.; Simmons, Kevin L.; van Hassel, Bart

    2014-12-01

    In this paper, the system designs for hydrogen storage using chemical hydrogen materials in an 80-kWe fuel cell, light-duty vehicle are described. Ammonia borane and alane are used for these designs to represent the general classes of exothermic and endothermic materials. The designs are then compared to the USDRIVE/DOE-developed set of system-level targets for onboard storage. While most DOE targets are predicted to be achieved based on the modeling, the system gravimetric and volumetric densities were more challenging and became the focus of this work. The resulting system evaluation determined that the slurry accounts for the majority of the system mass. Only modest reductions in the system mass can be expected with improvements in the balance-of-plant components. Most of the gravimetric improvements will require developing materials with higher inherent storage capacity or by increasing the solids loading of the chemical hydrogen storage material in the slurry.

  1. Slurry-Based Chemical Hydrogen Storage Systems for Automotive Fuel Cell Applications

    SciTech Connect

    Brooks, Kriston P.; Semelsberger, Troy; Simmons, Kevin L.; Van Hassel, Bart A.

    2014-05-30

    In this paper, the system designs for hydrogen storage using chemical hydrogen materials in an 80 kWe fuel cell, light-duty vehicle are described. Ammonia borane and alane are used for these designs to represent the general classes of exothermic and endothermic materials. The designs are then compared to the USDRIVE/DOE developed set of system level targets for on-board storage. While most of the DOE targets are predicted to be achieved based on the modeling, the system gravimetric and volumetric densities were more challenging and became the focus of this work. The resulting system evaluation determined that the slurry is majority of the system mass. Only modest reductions in the system mass can be expected with improvements in the balance of plant components. Most of the gravimetric improvements will require developing materials with higher inherent storage capacity or by increasing the solids loading of the chemical hydrogen storage material in the slurry.

  2. Systems Modeling, Simulation and Material Operating Requirements for Chemical Hydride Based Hydrogen Storage

    SciTech Connect

    Devarakonda, Maruthi N.; Brooks, Kriston P.; Ronnebro, Ewa; Rassat, Scot D.

    2012-02-01

    Research on ammonia borane (AB, NH3BH3) has shown it to be a promising material for chemical hydride based hydrogen storage. AB was selected by DOE's Hydrogen Storage Engineering Center of Excellence (HSECoE) as the initial chemical hydride of study because of its high hydrogen storage capacity (up to 19.6% by weight for the release of {approx}2.5 molar equivalents of hydrogen gas) and its stability under typical ambient conditions. A new systems concept based on augers, ballast tank, hydrogen heat exchanger and H2 burner was designed and implemented in simulation. In this design, the chemical hydride material was assumed to produce H2 on the augers itself, thus minimizing the size of ballast tank and reactor. One dimensional models based on conservation of mass, species and energy were used to predict important state variables such as reactant and product concentrations, temperatures of various components, flow rates, along with pressure, in various components of the storage system. Various subsystem components in the models were coded as C language S-functions and implemented in Matlab/Simulink environment. The control variable AB (or alane) flow rate was determined through a simple expression based on the ballast tank pressure, H2 demand from the fuel cell and hydrogen production from AB (or alane) in the reactor. System simulation results for solid AB, liquid AB and alane for both steady state and transient drive cycle cases indicate the usefulness of the model for further analysis and prototype development.

  3. System simulation of compressed hydrogen storage based residential wind hybrid power systems

    NASA Astrophysics Data System (ADS)

    Raju, Mandhapati; Khaitan, Siddhartha Kumar

    2012-07-01

    This paper deals with the storage of excess wind energy, in a hybrid wind power system, in the form of compressed hydrogen. A system simulation model is developed in Matlab/Simulink platform for the charging and discharging dynamics of compressed hydrogen storage system integrated with the wind turbine and the fuel cell. Wind model is used to estimate the power generation in the wind turbine. When the wind power generation exceeds the load, the excess power is diverted to the electrolyzer to produce hydrogen. As and when the pressure inside the electrolyzer builds, a compressor is operated intermittently (for higher efficiency) to divert the hydrogen into high pressure cylinders. When demand exceeds the power generation, fuel cell supplies the power to the load. A number of fuel cell stacks are provided to meet the required load. The overall efficiency of the storage system, defined as the ratio of the useful energy derived from the storage system to the energy diverted to the storage system is found to be 24.5% for the compressed hydrogen storage based system.

  4. Improved Mg-based alloys for hydrogen storage

    SciTech Connect

    Sapru, K.; Ming, L.; Stetson, N.T.; Evans, J.

    1998-08-01

    The overall objective of this on-going work is to develop low temperature alloys capable of reversibly storing at least 3 wt.% hydrogen, allowing greater than for 2 wt.% at the system level which is required by most applications. Surface modification of Mg can be used to improve its H-sorption kinetics. The authors show here that the same Mg-transition metal-based multi-component alloy when prepared by melt-spinning results in a more homogeneous materials with a higher plateau pressure as compared to preparing the material by mechanical grinding. They have also shown that mechanically alloyed Mg{sub 50}Al{sub 45}Zn{sub 5} results in a sample having a higher plateau pressure.

  5. Advancement of Systems Designs and Key Engineering Technologies for Materials Based Hydrogen Storage

    SciTech Connect

    van Hassel, Bart A.

    2015-09-18

    UTRC lead the development of the Simulink Framework model that enables a comparison of different hydrogen storage systems on a common basis. The Simulink Framework model was disseminated on the www.HSECoE.org website that is hosted by NREL. UTRC contributed to a better understanding of the safety aspects of the proposed hydrogen storage systems. UTRC also participated in the Failure Mode and Effect Analysis of both the chemical- and the adsorbent-based hydrogen storage system during Phase 2 of the Hydrogen Storage Engineering Center of Excellence. UTRC designed a hydrogen storage system with a reversible metal hydride material in a compacted form for light-duty vehicles with a 5.6 kg H2 storage capacity, giving it a 300 miles range. It contains a heat exchanger that enables efficient cooling of the metal hydride material during hydrogen absorption in order to meet the 3.3 minute refueling time target. It has been shown through computation that the kinetics of hydrogen absorption of Ti-catalyzed NaAlH4 was ultimately limiting the rate of hydrogen absorption to 85% of the material capacity in 3.3 minutes. An inverse analysis was performed in order to determine the material property requirements in order for a metal hydride based hydrogen storage system to meet the DOE targets. Work on metal hydride storage systems was halted after the Phase 1 to Phase 2 review due to the lack of metal hydride materials with the required material properties. UTRC contributed to the design of a chemical hydrogen storage system by developing an adsorbent for removing the impurity ammonia from the hydrogen gas, by developing a system to meter the transport of Ammonia Borane (AB) powder to a thermolysis reactor, and by developing a gas-liquid-separator (GLS) for the separation of hydrogen gas from AB slurry in silicone oil. Stripping impurities from hydrogen gas is essential for a long life of the fuel cell system on board of a vehicle. Work on solid transport of AB was halted after the

  6. Seasonal energy storage system based on hydrogen for self sufficient living

    NASA Astrophysics Data System (ADS)

    Bielmann, M.; Vogt, U. F.; Zimmermann, M.; Züttel, A.

    SELF is a resource independent living and working environment. By on-board renewable electricity generation and storage, it accounts for all aspects of living, such as space heating and cooking as well as providing a purified rainwater supply and wastewater treatment, excluding food supply. Uninterrupted, on-demand energy and water supply are the key challenges. Off-grid renewable power supply fluctuations on daily and seasonal time scales impose production gaps that have to be served by local storage, a function normally fulfilled by the grid. While daily variations only obligate a small storage capacity, requirements for seasonal storage are substantial. The energy supply for SELF is reviewed based on real meteorological data and demand patterns for Zurich, Switzerland. A battery system with propane for cooking serves as a reference for battery-only and hybrid battery/hydrogen systems. In the latter, hydrogen is used for cooking and electricity generation. The analysis shows that hydrogen is ideal for long term bulk energy storage on a seasonal timescale, while batteries are best suited for short term energy storage. Although the efficiency penalty from hydrogen generation is substantial, in off-grid systems, this parameter is tolerable since the harvesting ratio of photovoltaic energy is limited by storage capacity.

  7. Integrating hydrogen generation and storage in a novel compact electrochemical system based on metal hydrides

    NASA Astrophysics Data System (ADS)

    Rangel, C. M.; Fernandes, V. R.; Slavkov, Y.; Bozukov, L.

    The development of efficient and reliable energy storage systems based on hydrogen technology represents a challenge to seasonal storage based on renewable hydrogen. State of the art renewable energy generation systems include separate units such as electrolyzer, hydrogen storage vessel and a fuel cell system for the conversion of H 2 back into electricity, when required. In this work, a novel electrochemical system has been developed which integrates hydrogen production, storage and compression in only one device, at relatively low cost and high efficiency. The developed prototype comprises a six-electrode cell assembly using an AB 5-type metal hydride and Ni plates as counter electrodes, in a 35-wt% KOH solution. Metal hydride electrodes with chemical composition LaNi 4.3Co 0.4Al 0.3 were prepared by high frequency vacuum melting followed by high temperature annealing. X-ray phase analysis showed typical hexagonal structure and no traces of other intermetallic compounds belonging to the La-Ni phase diagram. Thermodynamic study has been performed in a Sieverts type of apparatus produced by Labtech Int. During cycling, the charging/discharging process was studied in situ using a gas chromatograph from Agilent. It is anticipated that the device will be integrated as a combined hydrogen generator and storage unit in a stand-alone system associated to a 1-kW fuel cell.

  8. Model based design of an automotive-scale, metal hydride hydrogen storage system.

    SciTech Connect

    Johnson, Terry Alan; Kanouff, Michael P.; Jorgensen, Scott W.; Dedrick, Daniel E.; Evans, Gregory Herbert

    2010-11-01

    Sandia and General Motors have successfully designed, fabricated, and experimentally operated a vehicle-scale hydrogen storage system using the complex metal hydride sodium alanate. Over the 6 year project, the team tackled the primary barriers associated with storage and delivery of hydrogen including mass, volume, efficiency and cost. The result was the hydrogen storage demonstration system design. The key technologies developed for this hydrogen storage system include optimal heat exchange designs, thermal properties enhancement, a unique catalytic hydrogen burner and energy efficient control schemes. The prototype system designed, built, and operated to demonstrate these technologies consists of four identical hydrogen storage modules with a total hydrogen capacity of 3 kg. Each module consists of twelve stainless steel tubes that contain the enhanced sodium alanate. The tubes are arranged in a staggered, 4 x 3 array and enclosed by a steel shell to form a shell and tube heat exchanger. Temperature control during hydrogen absorption and desorption is accomplished by circulating a heat transfer fluid through each module shell. For desorption, heat is provided by the catalytic oxidation of hydrogen within a high efficiency, compact heat exchanger. The heater was designed to transfer up to 30 kW of heat from the catalytic reaction to the circulating heat transfer fluid. The demonstration system module design and the system control strategies were enabled by experiment-based, computational simulations that included heat and mass transfer coupled with chemical kinetics. Module heat exchange systems were optimized using multi-dimensional models of coupled fluid dynamics and heat transfer. Chemical kinetics models were coupled with both heat and mass transfer calculations to design the sodium alanate vessels. Fluid flow distribution was a key aspect of the design for the hydrogen storage modules and computational simulations were used to balance heat transfer with

  9. Hydrogen storage methods.

    PubMed

    Züttel, Andreas

    2004-04-01

    Hydrogen exhibits the highest heating value per mass of all chemical fuels. Furthermore, hydrogen is regenerative and environmentally friendly. There are two reasons why hydrogen is not the major fuel of today's energy consumption. First of all, hydrogen is just an energy carrier. And, although it is the most abundant element in the universe, it has to be produced, since on earth it only occurs in the form of water and hydrocarbons. This implies that we have to pay for the energy, which results in a difficult economic dilemma because ever since the industrial revolution we have become used to consuming energy for free. The second difficulty with hydrogen as an energy carrier is its low critical temperature of 33 K (i.e. hydrogen is a gas at ambient temperature). For mobile and in many cases also for stationary applications the volumetric and gravimetric density of hydrogen in a storage material is crucial. Hydrogen can be stored using six different methods and phenomena: (1) high-pressure gas cylinders (up to 800 bar), (2) liquid hydrogen in cryogenic tanks (at 21 K), (3) adsorbed hydrogen on materials with a large specific surface area (at T<100 K), (4) absorbed on interstitial sites in a host metal (at ambient pressure and temperature), (5) chemically bonded in covalent and ionic compounds (at ambient pressure), or (6) through oxidation of reactive metals, e.g. Li, Na, Mg, Al, Zn with water. The most common storage systems are high-pressure gas cylinders with a maximum pressure of 20 MPa (200 bar). New lightweight composite cylinders have been developed which are able to withstand pressures up to 80 MPa (800 bar) and therefore the hydrogen gas can reach a volumetric density of 36 kg.m(-3), approximately half as much as in its liquid state. Liquid hydrogen is stored in cryogenic tanks at 21.2 K and ambient pressure. Due to the low critical temperature of hydrogen (33 K), liquid hydrogen can only be stored in open systems. The volumetric density of liquid hydrogen

  10. Hydrogen storage methods

    NASA Astrophysics Data System (ADS)

    Züttel, Andreas

    Hydrogen exhibits the highest heating value per mass of all chemical fuels. Furthermore, hydrogen is regenerative and environmentally friendly. There are two reasons why hydrogen is not the major fuel of today's energy consumption. First of all, hydrogen is just an energy carrier. And, although it is the most abundant element in the universe, it has to be produced, since on earth it only occurs in the form of water and hydrocarbons. This implies that we have to pay for the energy, which results in a difficult economic dilemma because ever since the industrial revolution we have become used to consuming energy for free. The second difficulty with hydrogen as an energy carrier is its low critical temperature of 33 K (i.e. hydrogen is a gas at ambient temperature). For mobile and in many cases also for stationary applications the volumetric and gravimetric density of hydrogen in a storage material is crucial. Hydrogen can be stored using six different methods and phenomena: (1) high-pressure gas cylinders (up to 800 bar), (2) liquid hydrogen in cryogenic tanks (at 21 K), (3) adsorbed hydrogen on materials with a large specific surface area (at T<100 K), (4) absorbed on interstitial sites in a host metal (at ambient pressure and temperature), (5) chemically bonded in covalent and ionic compounds (at ambient pressure), or (6) through oxidation of reactive metals, e.g. Li, Na, Mg, Al, Zn with water. The most common storage systems are high-pressure gas cylinders with a maximum pressure of 20 MPa (200 bar). New lightweight composite cylinders have been developed which are able to withstand pressures up to 80 MPa (800 bar) and therefore the hydrogen gas can reach a volumetric density of 36 kg.m-3, approximately half as much as in its liquid state. Liquid hydrogen is stored in cryogenic tanks at 21.2 K and ambient pressure. Due to the low critical temperature of hydrogen (33 K), liquid hydrogen can only be stored in open systems. The volumetric density of liquid hydrogen is

  11. Progress on first-principles-based materials design for hydrogen storage

    PubMed Central

    Park, Noejung; Choi, Keunsu; Hwang, Jeongwoon; Kim, Dong Wook; Kim, Dong Ok; Ihm, Jisoon

    2012-01-01

    This article briefly summarizes the research activities in the field of hydrogen storage in sorbent materials and reports our recent works and future directions for the design of such materials. Distinct features of sorption-based hydrogen storage methods are described compared with metal hydrides and complex chemical hydrides. We classify the studies of hydrogen sorbent materials in terms of two key technical issues: (i) constructing stable framework structures with high porosity, and (ii) increasing the binding affinity of hydrogen molecules to surfaces beyond the usual van der Waals interaction. The recent development of reticular chemistry is summarized as a means for addressing the first issue. Theoretical studies focus mainly on the second issue and can be grouped into three classes according to the underlying interaction mechanism: electrostatic interactions based on alkaline cations, Kubas interactions with open transition metals, and orbital interactions involving Ca and other nontransitional metals. Hierarchical computational methods to enable the theoretical predictions are explained, from ab initio studies to molecular dynamics simulations using force field parameters. We also discuss the actual delivery amount of stored hydrogen, which depends on the charging and discharging conditions. The usefulness and practical significance of the hydrogen spillover mechanism in increasing the storage capacity are presented as well. PMID:23161910

  12. Progress on first-principles-based materials design for hydrogen storage.

    PubMed

    Park, Noejung; Choi, Keunsu; Hwang, Jeongwoon; Kim, Dong Wook; Kim, Dong Ok; Ihm, Jisoon

    2012-12-04

    This article briefly summarizes the research activities in the field of hydrogen storage in sorbent materials and reports our recent works and future directions for the design of such materials. Distinct features of sorption-based hydrogen storage methods are described compared with metal hydrides and complex chemical hydrides. We classify the studies of hydrogen sorbent materials in terms of two key technical issues: (i) constructing stable framework structures with high porosity, and (ii) increasing the binding affinity of hydrogen molecules to surfaces beyond the usual van der Waals interaction. The recent development of reticular chemistry is summarized as a means for addressing the first issue. Theoretical studies focus mainly on the second issue and can be grouped into three classes according to the underlying interaction mechanism: electrostatic interactions based on alkaline cations, Kubas interactions with open transition metals, and orbital interactions involving Ca and other nontransitional metals. Hierarchical computational methods to enable the theoretical predictions are explained, from ab initio studies to molecular dynamics simulations using force field parameters. We also discuss the actual delivery amount of stored hydrogen, which depends on the charging and discharging conditions. The usefulness and practical significance of the hydrogen spillover mechanism in increasing the storage capacity are presented as well.

  13. Hydrogen Storage Technical Team Roadmap

    SciTech Connect

    2013-06-01

    The mission of the Hydrogen Storage Technical Team is to accelerate research and innovation that will lead to commercially viable hydrogen-storage technologies that meet the U.S. DRIVE Partnership goals.

  14. Combining photocatalytic hydrogen generation and capsule storage in graphene based sandwich structures

    PubMed Central

    Yang, Li; Li, Xiyu; Zhang, Guozhen; Cui, Peng; Wang, Xijun; Jiang, Xiang; Zhao, Jin; Luo, Yi; Jiang, Jun

    2017-01-01

    The challenge of safe hydrogen storage has limited the practical application of solar-driven photocatalytic water splitting. It is hard to isolate hydrogen from oxygen products during water splitting to avoid unwanted reverse reaction or explosion. Here we propose a multi-layer structure where a carbon nitride is sandwiched between two graphene sheets modified by different functional groups. First-principles simulations demonstrate that such a system can harvest light and deliver photo-generated holes to the outer graphene-based sheets for water splitting and proton generation. Driven by electrostatic attraction, protons penetrate through graphene to react with electrons on the inner carbon nitride to generate hydrogen molecule. The produced hydrogen is completely isolated and stored with a high-density level within the sandwich, as no molecules could migrate through graphene. The ability of integrating photocatalytic hydrogen generation and safe capsule storage has made the sandwich system an exciting candidate for realistic solar and hydrogen energy utilization. PMID:28681839

  15. Hydrogen storage in Ti, V and their oxides-based thin films

    NASA Astrophysics Data System (ADS)

    Tarnawski, Z.; Zakrzewska, K.; Kim-Ngan, N.-T. H.; Krupska, M.; Sowa, S.; Drogowska, K.; Havela, L.; Balogh, A. G.

    2015-03-01

    We have investigated the hydrogen storage ability and the effect of hydrogenation on structure and physical properties of Ti/V and their oxides-based thin films. A series of Ti-TiO2 and VOx-TiO2 thin films with different layer structures, geometries and thicknesses have been prepared by the sputtering technique on different (Si(111), SiO2, C) substrates. For the Ti-TiO2-Ti films up to 50 at.% of hydrogen can be stored in the Ti layers, while the hydrogen can penetrate without accumulation through the TiO2 layer. A large hydrogen storage was also found in some V2O5-TiO2 films. Hydrogen could also remove the preferential orientation in the Ti films and induce a transition of V2O5 to VO2 in the films. Invited talk at the 7th International Workshop on Advanced Materials Science and Nanotechnology IWAMSN2014, 2-6 November, 2014, Ha Long, Vietnam.

  16. Nanostructured materials for hydrogen storage

    DOEpatents

    Williamson, Andrew J.; Reboredo, Fernando A.

    2007-12-04

    A system for hydrogen storage comprising a porous nano-structured material with hydrogen absorbed on the surfaces of the porous nano-structured material. The system of hydrogen storage comprises absorbing hydrogen on the surfaces of a porous nano-structured semiconductor material.

  17. A review on on-board challenges of magnesium-based hydrogen storage materials for automobile applications

    NASA Astrophysics Data System (ADS)

    Rahman, Md. Wasikur

    2017-06-01

    The attempt of the review is to realize on-board hydrogen storage technologies concerning magnesium based solid-state matrix to allow fuel cell devices to facilitate sufficient storage capacity, cost, safety and performance requirements to be competitive with current vehicles. Hydrogen, a potential and clean fuel, can be applied in the state-of-the-art technology of `zero emission' vehicles. Hydrogen economy infrastructure both for stationary and mobile purposes is complicated due to its critical physico-chemical properties and materials play crucial roles in every stage of hydrogen production to utilization in fuel cells in achieving high conversion efficiency, safety and robustness of the technologies involved. Moreover, traditional hydrogen storage facilities are rather complicated due to its anomalous properties such as highly porous solids and polymers have intrinsic microporosity, which is the foremost favorable characteristics of fast kinetics and reversibility, but the major drawback is the low storage capacity. In contrast, metal hydrides and complex hydrides have high hydrogen storage capacity but thermodynamically unfavorable. Therefore, hydrogen storage is a real challenge to realize `hydrogen economy' that will solve the critical issues of humanity such as energy depletion, greenhouse emission, air pollution and ultimately climate change. Magnesium based materials, particularly magnesium hydride (MgH2) has been proposed as a potential hydrogen storage material due to its high gravimetric and volumetric capacity as well as environmentally benign properties to work the grand challenge out.

  18. Carborane-Based Metal-Organic Framework with High Methane and Hydrogen Storage Capacities

    SciTech Connect

    Kennedy, RD; Krungleviciute, V; Clingerman, DJ; Mondloch, JE; Peng, Y; Wilmer, CE; Sarjeant, AA; Snurr, RQ; Hupp, JT; Yildirim, T; Farha, OK; Mirkin, CA

    2013-09-10

    A Cu-carborane-based metal organic framework (MOF), NU-135, which contains a quasi-spherical para-carborane moiety, has been synthesized and characterized. NU-135 exhibits a pore volume of 1.02 cm(3)/g and a gravimetric BET surface area of ca. 2600 m(2)/g, and thus represents the first highly porous carborane-based MOF. As a consequence of the, unique geometry of the carborane unit, NU-135 has a very high volumetric BET surface area of ca. 1900 m(2)/cm(3). CH4, CO2, and H-2 adsorption isotherms were measured over a broad range of pressures and temperatures and are in good agreement with computational predictions. The methane storage capacity of NU-135 at 35 bar and 298 K is ca. 187 v(STP)/v. At 298 K, the pressure required to achieve a methane storage density comparable to that of a compressed natural gas (CNG) tank pressurized to 212 bar, which is a typical storage pressure, is only 65 bar. The methane working capacity (5-65 bar) is 170 v(STP)/v. The volumetric hydrogen storage capacity at 55 bar and 77 K is 49 g/L. These properties are comparable to those of current record holders in the area of methane and hydrogen storage. This initial example lays the groundwork for carborane-based materials with high surface areas.

  19. Prospects for hydrogen storage in graphene.

    PubMed

    Tozzini, Valentina; Pellegrini, Vittorio

    2013-01-07

    Hydrogen-based fuel cells are promising solutions for the efficient and clean delivery of electricity. Since hydrogen is an energy carrier, a key step for the development of a reliable hydrogen-based technology requires solving the issue of storage and transport of hydrogen. Several proposals based on the design of advanced materials such as metal hydrides and carbon structures have been made to overcome the limitations of the conventional solution of compressing or liquefying hydrogen in tanks. Nevertheless none of these systems are currently offering the required performances in terms of hydrogen storage capacity and control of adsorption/desorption processes. Therefore the problem of hydrogen storage remains so far unsolved and it continues to represent a significant bottleneck to the advancement and proliferation of fuel cell and hydrogen technologies. Recently, however, several studies on graphene, the one-atom-thick membrane of carbon atoms packed in a honeycomb lattice, have highlighted the potentialities of this material for hydrogen storage and raise new hopes for the development of an efficient solid-state hydrogen storage device. Here we review on-going efforts and studies on functionalized and nanostructured graphene for hydrogen storage and suggest possible developments for efficient storage/release of hydrogen under ambient conditions.

  20. High efficiency stationary hydrogen storage

    SciTech Connect

    Hynek, S.; Fuller, W.; Truslow, S.

    1995-09-01

    Stationary storage of hydrogen permits one to make hydrogen now and use it later. With stationary hydrogen storage, one can use excess electrical generation capacity to power an electrolyzer, and store the resultant hydrogen for later use or transshipment. One can also use stationary hydrogen as a buffer at fueling stations to accommodate non-steady fueling demand, thus permitting the hydrogen supply system (e.g., methane reformer or electrolyzer) to be sized to meet the average, rather than the peak, demand. We at ADL designed, built, and tested a stationary hydrogen storage device that thermally couples a high-temperature metal hydride to a phase change material (PCM). The PCM captures and stores the heat of the hydriding reaction as its own heat of fusion (that is, it melts), and subsequently returns that heat of fusion (by freezing) to facilitate the dehydriding reaction. A key component of this stationary hydrogen storage device is the metal hydride itself. We used nickel-coated magnesium powder (NCMP) - magnesium particles coated with a thin layer of nickel by means of chemical vapor deposition (CVD). Magnesium hydride can store a higher weight fraction of hydrogen than any other practical metal hydride, and it is less expensive than any other metal hydride. We designed and constructed an experimental NCM/PCM reactor out of 310 stainless steel in the form of a shell-and-tube heat exchanger, with the tube side packed with NCMP and the shell side filled with a eutectic mixture of NaCL, KCl, and MgCl{sub 2}. Our experimental results indicate that with proper attention to limiting thermal losses, our overall efficiency will exceed 90% (DOE goal: >75%) and our overall system cost will be only 33% (DOE goal: <50%) of the value of the delivered hydrogen. It appears that NCMP can be used to purify hydrogen streams and store hydrogen at the same time. These prospects make the NCMP/PCM reactor an attractive component in a reformer-based hydrogen fueling station.

  1. Enhancing hydrogen spillover and storage

    DOEpatents

    Yang, Ralph T.; Li, Yingwel; Lachawiec, Jr., Anthony J.

    2011-05-31

    Methods for enhancing hydrogen spillover and storage are disclosed. One embodiment of the method includes doping a hydrogen receptor with metal particles, and exposing the hydrogen receptor to ultrasonification as doping occurs. Another embodiment of the method includes doping a hydrogen receptor with metal particles, and exposing the doped hydrogen receptor to a plasma treatment.

  2. Enhancing hydrogen spillover and storage

    DOEpatents

    Yang, Ralph T; Li, Yingwei; Lachawiec, Jr., Anthony J

    2013-02-12

    Methods for enhancing hydrogen spillover and storage are disclosed. One embodiment of the method includes doping a hydrogen receptor with metal particles, and exposing the hydrogen receptor to ultrasonication as doping occurs. Another embodiment of the method includes doping a hydrogen receptor with metal particles, and exposing the doped hydrogen receptor to a plasma treatment.

  3. Gas storage materials, including hydrogen storage materials

    DOEpatents

    Mohtadi, Rana F; Wicks, George G; Heung, Leung K; Nakamura, Kenji

    2013-02-19

    A material for the storage and release of gases comprises a plurality of hollow elements, each hollow element comprising a porous wall enclosing an interior cavity, the interior cavity including structures of a solid-state storage material. In particular examples, the storage material is a hydrogen storage material such as a solid state hydride. An improved method for forming such materials includes the solution diffusion of a storage material solution through a porous wall of a hollow element into an interior cavity.

  4. Gas storage materials, including hydrogen storage materials

    DOEpatents

    Mohtadi, Rana F; Wicks, George G; Heung, Leung K; Nakamura, Kenji

    2014-11-25

    A material for the storage and release of gases comprises a plurality of hollow elements, each hollow element comprising a porous wall enclosing an interior cavity, the interior cavity including structures of a solid-state storage material. In particular examples, the storage material is a hydrogen storage material, such as a solid state hydride. An improved method for forming such materials includes the solution diffusion of a storage material solution through a porous wall of a hollow element into an interior cavity.

  5. Hydrogen storage: beyond conventional methods.

    PubMed

    Dalebrook, Andrew F; Gan, Weijia; Grasemann, Martin; Moret, Séverine; Laurenczy, Gábor

    2013-10-09

    The efficient storage of hydrogen is one of three major hurdles towards a potential hydrogen economy. This report begins with conventional storage methods for hydrogen and broadly covers new technology, ranging from physical media involving solid adsorbents, to chemical materials including metal hydrides, ammonia borane and liquid precursors such as alcohols and formic acid.

  6. Reversible hydrogen storage materials

    DOEpatents

    Ritter, James A [Lexington, SC; Wang, Tao [Columbia, SC; Ebner, Armin D [Lexington, SC; Holland, Charles E [Cayce, SC

    2012-04-10

    In accordance with the present disclosure, a process for synthesis of a complex hydride material for hydrogen storage is provided. The process includes mixing a borohydride with at least one additive agent and at least one catalyst and heating the mixture at a temperature of less than about 600.degree. C. and a pressure of H.sub.2 gas to form a complex hydride material. The complex hydride material comprises MAl.sub.xB.sub.yH.sub.z, wherein M is an alkali metal or group IIA metal, Al is the element aluminum, x is any number from 0 to 1, B is the element boron, y is a number from 0 to 13, and z is a number from 4 to 57 with the additive agent and catalyst still being present. The complex hydride material is capable of cyclic dehydrogenation and rehydrogenation and has a hydrogen capacity of at least about 4 weight percent.

  7. INTEGRATED HYDROGEN STORAGE SYSTEM MODEL

    SciTech Connect

    Hardy, B

    2007-11-16

    Hydrogen storage is recognized as a key technical hurdle that must be overcome for the realization of hydrogen powered vehicles. Metal hydrides and their doped variants have shown great promise as a storage material and significant advances have been made with this technology. In any practical storage system the rate of H2 uptake will be governed by all processes that affect the rate of mass transport through the bed and into the particles. These coupled processes include heat and mass transfer as well as chemical kinetics and equilibrium. However, with few exceptions, studies of metal hydrides have focused primarily on fundamental properties associated with hydrogen storage capacity and kinetics. A full understanding of the complex interplay of physical processes that occur during the charging and discharging of a practical storage system requires models that integrate the salient phenomena. For example, in the case of sodium alanate, the size of NaAlH4 crystals is on the order of 300nm and the size of polycrystalline particles may be approximately 10 times larger ({approx}3,000nm). For the bed volume to be as small as possible, it is necessary to densely pack the hydride particles. Even so, in packed beds composed of NaAlH{sub 4} particles alone, it has been observed that the void fraction is still approximately 50-60%. Because of the large void fraction and particle to particle thermal contact resistance, the thermal conductivity of the hydride is very low, on the order of 0.2 W/m-{sup o}C, Gross, Majzoub, Thomas and Sandrock [2002]. The chemical reaction for hydrogen loading is exothermic. Based on the data in Gross [2003], on the order of 10{sup 8}J of heat of is released for the uptake of 5 kg of H{sub 2}2 and complete conversion of NaH to NaAlH{sub 4}. Since the hydride reaction transitions from hydrogen loading to discharge at elevated temperatures, it is essential to control the temperature of the bed. However, the low thermal conductivity of the hydride

  8. Theoretical realization of cluster-assembled hydrogen storage materials based on terminated carbon atomic chains.

    PubMed

    Liu, Chun-Sheng; An, Hui; Guo, Ling-Ju; Zeng, Zhi; Ju, Xin

    2011-01-14

    The capacity of carbon atomic chains with different terminations for hydrogen storage is studied using first-principles density functional theory calculations. Unlike the physisorption of H(2) on the H-terminated chain, we show that two Li (Na) atoms each capping one end of the odd- or even-numbered carbon chain can hold ten H(2) molecules with optimal binding energies for room temperature storage. The hybridization of the Li 2p states with the H(2)σ orbitals contributes to the H(2) adsorption. However, the binding mechanism of the H(2) molecules on Na arises only from the polarization interaction between the charged Na atom and the H(2). Interestingly, additional H(2) molecules can be bound to the carbon atoms at the chain ends due to the charge transfer between Li 2s2p (Na 3s) and C 2p states. More importantly, dimerization of these isolated metal-capped chains does not affect the hydrogen binding energy significantly. In addition, a single chain can be stabilized effectively by the C(60) fullerenes termination. With a hydrogen uptake of ∼10 wt.% on Li-coated C(60)-C(n)-C(60) (n = 5, 8), the Li(12)C(60)-C(n)-Li(12)C(60) complex, keeping the number of adsorbed H(2) molecules per Li and stabilizing the dispersion of individual Li atoms, can serve as better building blocks of polymers than the (Li(12)C(60))(2) dimer. These findings suggest a new route to design cluster-assembled hydrogen storage materials based on terminated sp carbon chains.

  9. Exploring several different routes to produce Mg- based nanomaterials for Hydrogen storage

    NASA Astrophysics Data System (ADS)

    Leiva, D. R.; Chanchetti, L. F.; Floriano, R.; Ishikawa, T. T.; Botta, W. J.

    2014-08-01

    Severe mechanical processing routes based on high-energy ball milling (HEBM) or severe plastic deformation (SPD) can be used to produce Mg nanomaterials for hydrogen storage applications. In the last few years, we have been exploring in our research group different SPD processing routes in Mg systems to achieve good activation (first hydrogenation) and fast H-absorption/desorption kinetics, combined with enhanced air resistance. In this paper, we compare SPD techniques applied to Mg with HEBM applied to MgH2. Both advanced - melt spinning (MS), high-pressure torsion (HPT) - and more conventional - cold rolling (CR), cold forging (CF)- techniques are evaluated as means of production of bulk samples with very refined microstructures and controlled textures. In the best SPD processing conditions, attractive H-absorption/desorption kinetic properties are obtained, which are comparable to the ones of MgH2 milled powders, even if the needed temperatures are higher - 350°C compared to 300°C.CR and CF stand out as the processes with higher potential for industrial application, considering the level of the attained hydrogen storage properties, its simplicity and low cost.

  10. Standardized hydrogen storage module with high utilization factor based on metal hydride-graphite composites

    NASA Astrophysics Data System (ADS)

    Bürger, Inga; Dieterich, Mila; Pohlmann, Carsten; Röntzsch, Lars; Linder, Marc

    2017-02-01

    In view of hydrogen based backup power systems or small-scale power2gas units, hydrogen storages based on metal hydrides offer a safe and reliable solution. By using Hydralloy C5 as suitable hydride forming alloy, the present tank design guarantees very simple operating conditions: pressures between 4 bar and 30 bar, temperatures between 15 °C and 40 °C and minimal efforts for thermal management in combination with fast and constant charging and discharging capabilities. The modular tank consists of 4 layers with 5 reactor tubes each that are filled with metal hydride-graphite composites of a diameter of 21 mm. Experiments show that each layer of this tank is able to desorb the desired amount of hydrogen for a fuel cell operation at electrical power of 160 Wel for 100 min reaching a utilization factor of 93% of the stored hydrogen at RC. Furthermore, the experimental results of modularity, increasing loads and the electric air ventilation are presented.

  11. Hydrogen storage and generation system

    DOEpatents

    Dentinger, Paul M.; Crowell, Jeffrey A. W.

    2010-08-24

    A system for storing and generating hydrogen generally and, in particular, a system for storing and generating hydrogen for use in an H.sub.2/O.sub.2 fuel cell. The hydrogen storage system uses the beta particles from a beta particle emitting material to degrade an organic polymer material to release substantially pure hydrogen. In a preferred embodiment of the invention, beta particles from .sup.63Ni are used to release hydrogen from linear polyethylene.

  12. Hydrogen storage systems based on magnesium hydride: from laboratory tests to fuel cell integration

    NASA Astrophysics Data System (ADS)

    de Rango, P.; Marty, P.; Fruchart, D.

    2016-02-01

    The paper reviews the state of the art of hydrogen storage systems based on magnesium hydride, emphasizing the role of thermal management, whose effectiveness depends on the effective thermal conductivity of the hydride, but also depends of other limiting factors such as wall contact resistance and convective exchanges with the heat transfer fluid. For daily cycles, the use of phase change material to store the heat of reaction appears to be the most effective solution. The integration with fuel cells (1 kWe proton exchange membrane fuel cell and solid oxide fuel cell) highlights the dynamic behaviour of these systems, which is related to the thermodynamic properties of MgH2. This allows for "self-adaptive" systems that do not require control of the hydrogen flow rate at the inlet of the fuel cell.

  13. Effective hydrogen storage: a strategic chemistry challenge.

    PubMed

    David, William I F

    2011-01-01

    This paper gives an overview of the current status and future potential of hydrogen storage from a chemistry perspective and is based on the concluding presentation of the Faraday Discussion 151--Hydrogen Storage Materials. The safe, effective and economical storage of hydrogen is one of the main scientific and technological challenges in the move towards a low-carbon economy. One key sector is transportation where future vehicles will most likely be developed around a balance of battery-electric and hydrogen fuel-cell electric technologies. Although there has been a very significant research effort in solid-state hydrogen storage, high-pressure gas storage combined with conventional metal hydrides is still seen as the current intermediate-term candidate for car manufacturers. Significant issues have arisen in the search for improved solid-state hydrogen storage materials; for example, facile reversibility has been a major challenge for many recently studied complex hydrides while physisorption in porous structures is still restricted to cryogenic temperatures. However, many systems fulfil the majority of necessary criteria for improved hydrogen storage--indeed, the discovery of reversibility in multicomponent hydride systems along with recent chemistry breakthroughs in off-board and solvent-assisted regeneration suggest that the goal of both improved on-board reversible and off-board regenerated hydrogen storage systems can be achieved.

  14. Isotope tracer study of hydrogen spillover on carbon-based adsorbents for hydrogen storage.

    PubMed

    Lachawiec, Anthony J; Yang, Ralph T

    2008-06-17

    A composite material comprising platinum nanoparticles supported on molecular sieve templated carbon was synthesized and found to adsorb 1.35 wt % hydrogen at 298 K and 100 atm. The isosteric heat of adsorption for the material at low coverage was approximately 14 kJ/mol, and it approached a value of 10.6 kJ/mol as coverage increased for pressures at and above 1 atm. The increase in capacity is attributed to spillover, which is observed with the use of isotopic tracer TPD. IRMOF-8 bridged to Pt/C, a material known to exhibit hydrogen spillover at room temperature, was also studied with the hydrogen-deuterium scrambling reaction for comparison. The isotherms were reversible. For desorption, sequential doses of H2 and D2 at room temperature and subsequent TPD yield product distributions that are strong indicators of the surface diffusion controlled reverse spillover process.

  15. Hydrogen storage as a hydride. Citations from the International Aerospace Abstracts data base

    NASA Technical Reports Server (NTRS)

    Zollars, G. F.

    1980-01-01

    These citations from the international literature concern the storage of hydrogen in various metal hydrides. Binary and intermetallic hydrides are considered. Specific alloys discussed are iron titanium, lanthanium nickel, magnesium copper and magnesium nickel among others.

  16. Hydrogen storage as a hydride. Citations from the International Aerospace Abstracts data base

    NASA Technical Reports Server (NTRS)

    Zollars, G. F.

    1980-01-01

    These citations from the international literature concern the storage of hydrogen in various metal hydrides. Binary and intermetallic hydrides are considered. Specific alloys discussed are iron titanium, lanthanium nickel, magnesium copper and magnesium nickel among others.

  17. Energetics of hydrogen storage in organolithium nanostructures

    SciTech Connect

    Namilae, Sirish; Fuentes-Cabrera, Miguel A; Radhakrishnan, Balasubramaniam; Gorti, Sarma B; Nicholson, Don M

    2007-01-01

    Ab-initio calculations based on the second order Moller-Plesset perturbation theory (MP2) were used to investigate the interaction of molecular hydrogen with alkyl lithium organometallic compounds. It is found that lithium in organolithium structures attracts two hydrogen molecules with a binding energy of about 0.14 eV. The calculations also show that organolithium compounds bind strongly with graphitic nanostructures. Therefore, these carbon based nanostructures functionalized with organolithium compounds can be effectively used for storage of molecular hydrogen. Energetics and mechanisms for achieving high weight percent hydrogen storage in organolithium based nanostructures are discussed.

  18. Palladium on Nitrogen-Doped Mesoporous Carbon: A Bifunctional Catalyst for Formate-Based, Carbon-Neutral Hydrogen Storage.

    PubMed

    Wang, Fanan; Xu, Jinming; Shao, Xianzhao; Su, Xiong; Huang, Yanqiang; Zhang, Tao

    2016-02-08

    The lack of safe, efficient, and economical hydrogen storage technologies is a hindrance to the realization of the hydrogen economy. Reported herein is a reversible formate-based carbon-neutral hydrogen storage system that is established over a novel catalyst comprising palladium nanoparticles supported on nitrogen-doped mesoporous carbon. The support was fabricated by a hard template method and nitridated under a flow of ammonia. Detailed analyses demonstrate that this bicarbonate/formate redox equilibrium is promoted by the cooperative role of the doped nitrogen functionalities and the well-dispersed, electron-enriched palladium nanoparticles.

  19. An electrochemical investigation of mechanical alloying of MgNi-based hydrogen storage alloys

    NASA Astrophysics Data System (ADS)

    Jiang, Jian-Jun; Gasik, Michael

    The electrochemical properties of amorphous MgNi-based hydrogen storage alloys synthesized by mechanical alloying (MA) were evaluated. The results show that these amorphous Mg 50Ni 50 alloys exhibit a higher discharge capacity and relatively good rate capacity at a suitable grinding time while their cycle life is very poor. In order to improve the cycle life, the surface of the amorphous Mg 50Ni 50 alloy was coated with Ti, Al and Zr in Spex 8000 mill/mixer and the coating effects were further investigated. Based on experimental results, two kinds of MgNi-based amorphous alloys are designed by substituting part of Mg in MgNi-based alloys by suitable elements. These alloys are then composed of four components. Thus, the cycle life of electrodes consisting of these quaternary amorphous alloys is greatly improved.

  20. New Carbon-Based Porous Materials with Increased Heats of Adsorption for Hydrogen Storage

    SciTech Connect

    Snurr, Randall Q.; Hupp, Joseph T.; Kanatzidis, Mercouri G.; Nguyen, SonBinh T.

    2014-11-03

    Hydrogen fuel cell vehicles are a promising alternative to internal combustion engines that burn gasoline. A significant challenge in developing fuel cell vehicles is to store enough hydrogen on-board to allow the same driving range as current vehicles. One option for storing hydrogen on vehicles is to use tanks filled with porous materials that act as “sponges” to take up large quantities of hydrogen without the need for extremely high pressures. The materials must meet many requirements to make this possible. This project aimed to develop two related classes of porous materials to meet these requirements. All materials were synthesized from molecular constituents in a building-block approach, which allows for the creation of an incredibly wide variety of materials in a tailorable fashion. The materials have extremely high surface areas, to provide many locations for hydrogen to adsorb. In addition, they were designed to contain cations that create large electric fields to bind hydrogen strongly but not too strongly. Molecular modeling played a key role as a guide to experiment throughout the project. A major accomplishment of the project was the development of a material with record hydrogen uptake at cryogenic temperatures. Although the ultimate goal was materials that adsorb large quantities of hydrogen at room temperature, this achievement at cryogenic temperatures is an important step in the right direction. In addition, there is significant interest in applications at these temperatures. The hydrogen uptake, measured independently at NREL was 8.0 wt %. This is, to the best of our knowledge, the highest validated excess hydrogen uptake reported to date at 77 K. This material was originally sketched on paper based on a hypothesis that extended framework struts would yield materials with excellent hydrogen storage properties. However, before starting the synthesis, we used molecular modeling to assess the performance of the material for hydrogen uptake

  1. Polyhydride complexes for hydrogen storage

    SciTech Connect

    Jensen, C.M.

    1995-09-01

    Polyhydride metal complexes are being developed for application in hydrogen storage. Efforts have focused on developing complexes with improved available hydrogen weight percentages. We have explored the possibility that complexes containing aromatic hydrocarbon ligands could store hydrogen at both the metal center and in the ligands. We have synthesized novel indenyl hydride complexes and explored their reactivity with hydrogen. The reversible hydrogenation of [IrH{sub 3}(PPh{sub 3})({eta}{sup 5}-C{sub 10}H{sub 7})]{sup +} has been achieved. While attempting to prepare {eta}{sup 6}-tetrahydronaphthalene complexes, we discovered that certain polyhydride complexes catalyze both the hydrogenation and dehydrogenation of tetrahydronaphthalene.

  2. Hydrogen Storage in Metal Hydrides

    DTIC Science & Technology

    1990-08-01

    Hydrogen Storage Capacity Hydride by weight (%) [1) by volume (g/ml) [2] MgH2 7.00 0.101 Mg2NiH4 3.84 0,081 Mg2CuH4 2.04 - - 27 ...Include Security Classification) Hydrogen Storage in Metal Hydrides (U) 12. PERSONAL AUTHOR(S) DelaRosa, Mark J. 13a. TYPE OF REPORT 13b. TIME...objective of this program was to develop an economical process for pr-ducing a lightweight hydrogen storage medium by the chemical vapor infiltration

  3. Designing Microporus Carbons for Hydrogen Storage Systems

    SciTech Connect

    Alan C. Cooper

    2012-05-02

    An efficient, cost-effective hydrogen storage system is a key enabling technology for the widespread introduction of hydrogen fuel cells to the domestic marketplace. Air Products, an industry leader in hydrogen energy products and systems, recognized this need and responded to the DOE 'Grand Challenge' solicitation (DOE Solicitation DE-PS36-03GO93013) under Category 1 as an industry partner and steering committee member with the National Renewable Energy Laboratory (NREL) in their proposal for a center-of-excellence on Carbon-Based Hydrogen Storage Materials. This center was later renamed the Hydrogen Sorption Center of Excellence (HSCoE). Our proposal, entitled 'Designing Microporous Carbons for Hydrogen Storage Systems,' envisioned a highly synergistic 5-year program with NREL and other national laboratory and university partners.

  4. Catalyzed borohydrides for hydrogen storage

    DOEpatents

    Au, Ming [Augusta, GA

    2012-02-28

    A hydrogen storage material and process is provided in which alkali borohydride materials are created which contain effective amounts of catalyst(s) which include transition metal oxides, halides, and chlorides of titanium, zirconium, tin, and combinations of the various catalysts. When the catalysts are added to an alkali borodydride such as a lithium borohydride, the initial hydrogen release point of the resulting mixture is substantially lowered. Additionally, the hydrogen storage material may be rehydrided with weight percent values of hydrogen at least about 9 percent.

  5. New approaches to hydrogen storage.

    PubMed

    Graetz, Jason

    2009-01-01

    The emergence of a Hydrogen Economy will require the development of new media capable of safely storing hydrogen in a compact and light weight package. Metal hydrides and complex hydrides, where hydrogen is chemically bonded to the metal atoms in the bulk, offer some hope of overcoming the challenges associated with hydrogen storage. The objective is to find a material with a high volumetric and gravimetric hydrogen density that can also meet the unique demands of a low temperature automotive fuel cell. Currently, there is considerable effort to develop new materials with tunable thermodynamic and kinetic properties. This tutorial review provides an overview of the different types of metal hydrides and complex hydrides being investigated for on-board (reversible) and off-board (non-reversible) hydrogen storage along with a few new approaches to improving the hydrogenation-dehydrogenation properties.

  6. Hydrogen Storage in Carbon Nanotubes

    NASA Astrophysics Data System (ADS)

    Gilbert, Joseph; Gilbert, Matthew; Naab, Fabian; Savage, Lauren; Holland, Wayne; Duggan, Jerome; McDaniel, Floyd

    2004-10-01

    Hydrogen as a fuel source is an attractive, relatively clean alternative to fossil fuels. However, a major limitation in its use for the application of automobiles has been the requirement for an efficient hydrogen storage medium. Current hydrogen storage systems are: physical storage in high pressure tanks, metal hydride, and gas-on-solid absorption. However, these methods do not fulfill the Department of Energy's targeted requirements for a usable hydrogen storage capacity of 6.5 wt.%, operation near ambient temperature and pressure, quick extraction and refueling, reliability and reusability.Reports showing high capacity hydrogen storage in single-walled carbon nanotubes originally prompted great excitement in the field, but further research has shown conflicting results. Results for carbon nanostructures have ranged from less than 1 wt.% to 70 wt.%. The wide range of adsorption found in previous experiments results from the difficulty in measuring hydrogen in objects just nanometers in size. Most previous experiments relied on weight analysis and residual gas analysis to determine the amount of hydrogen being adsorbed by the CNTs. These differing results encouraged us to perform our own analysis on single-walled (SWNTs), double-walled (DWNTs), and multi-walled carbon nanotubes (MWNTs), as well as carbon fiber. We chose to utilize direct measurement of hydrogen in the materials using elastic recoil detection analysis (ERDA). This work was supported by the National Science Foundation's Research Experience for Undergraduates and the University of North Texas.

  7. Complex Hydrides for Hydrogen Storage

    SciTech Connect

    Slattery, Darlene; Hampton, Michael

    2003-03-10

    This report describes research into the use of complex hydrides for hydrogen storage. The synthesis of a number of alanates, (AIH4) compounds, was investigated. Both wet chemical and mechano-chemical methods were studied.

  8. Dynamic Modeling and Simulation Based Analysis of an Ammonia Borane (AB) Reactor System for Hydrogen Storage

    SciTech Connect

    Devarakonda, Maruthi N.; Holladay, Jamelyn D.; Brooks, Kriston P.; Rassat, Scot D.; Herling, Darrell R.

    2010-10-02

    Research on ammonia borane (AB, NH3BH3) has shown it to be a promising material for chemical hydrogen storage in PEM fuel cell applications. AB was selected by DOE’s Hydrogen Storage Engineering Center of Excellence (HSECoE) as the initial chemical hydride of study because of its high hydrogen storage capacity (up to 19.6% by weight for the release of three molar equivalents of hydrogen gas) and its stability under typical ambient conditions. A model of a bead reactor system which includes feed and product tanks, hot and cold augers, a ballast tank/reactor, a H2 burner and a radiator was developed to study AB system performance in an automotive application and estimate the energy, mass, and volume requirements for this off-board regenerable hydrogen storage material. Preliminary system simulation results for a start-up case and for a transient drive cycle indicate appropriate trends in the reactor system dynamics. A new controller was developed and validated in simulation for a couple of H2 demand cases.

  9. Complex hydrides for hydrogen storage

    DOEpatents

    Zidan, Ragaiy

    2006-08-22

    A hydrogen storage material and process of forming the material is provided in which complex hydrides are combined under conditions of elevated temperatures and/or elevated temperature and pressure with a titanium metal such as titanium butoxide. The resulting fused product exhibits hydrogen desorption kinetics having a first hydrogen release point which occurs at normal atmospheres and at a temperature between 50.degree. C. and 90.degree. C.

  10. Superior hydrogen storage in high entropy alloys

    NASA Astrophysics Data System (ADS)

    Sahlberg, Martin; Karlsson, Dennis; Zlotea, Claudia; Jansson, Ulf

    2016-11-01

    Metal hydrides (MHx) provide a promising solution for the requirement to store large amounts of hydrogen in a future hydrogen-based energy system. This requires the design of alloys which allow for a very high H/M ratio. Transition metal hydrides typically have a maximum H/M ratio of 2 and higher ratios can only be obtained in alloys based on rare-earth elements. In this study we demonstrate, for the first time to the best of our knowledge, that a high entropy alloy of TiVZrNbHf can absorb much higher amounts of hydrogen than its constituents and reach an H/M ratio of 2.5. We propose that the large hydrogen-storage capacity is due to the lattice strain in the alloy that makes it favourable to absorb hydrogen in both tetrahedral and octahedral interstitial sites. This observation suggests that high entropy alloys have future potential for use as hydrogen storage materials.

  11. Superior hydrogen storage in high entropy alloys.

    PubMed

    Sahlberg, Martin; Karlsson, Dennis; Zlotea, Claudia; Jansson, Ulf

    2016-11-10

    Metal hydrides (MHx) provide a promising solution for the requirement to store large amounts of hydrogen in a future hydrogen-based energy system. This requires the design of alloys which allow for a very high H/M ratio. Transition metal hydrides typically have a maximum H/M ratio of 2 and higher ratios can only be obtained in alloys based on rare-earth elements. In this study we demonstrate, for the first time to the best of our knowledge, that a high entropy alloy of TiVZrNbHf can absorb much higher amounts of hydrogen than its constituents and reach an H/M ratio of 2.5. We propose that the large hydrogen-storage capacity is due to the lattice strain in the alloy that makes it favourable to absorb hydrogen in both tetrahedral and octahedral interstitial sites. This observation suggests that high entropy alloys have future potential for use as hydrogen storage materials.

  12. Hydrogen storage container

    DOEpatents

    Wang, Jy-An John; Feng, Zhili; Zhang, Wei

    2017-02-07

    An apparatus and system is described for storing high-pressure fluids such as hydrogen. An inner tank and pre-stressed concrete pressure vessel share the structural and/or pressure load on the inner tank. The system and apparatus provide a high performance and low cost container while mitigating hydrogen embrittlement of the metal tank. System is useful for distributing hydrogen to a power grid or to a vehicle refueling station.

  13. Novel method of manufacturing hydrogen storage materials combining with numerical analysis based on discrete element method

    NASA Astrophysics Data System (ADS)

    Zhao, Xuzhe

    High efficiency hydrogen storage method is significant in development of fuel cell vehicle. Seeking for a high energy density material as the fuel becomes the key of wide spreading fuel cell vehicle. LiBH4 + MgH 2 system is a strong candidate due to their high hydrogen storage density and the reaction between them is reversible. However, LiBH4 + MgH 2 system usually requires the high temperature and hydrogen pressure for hydrogen release and uptake reaction. In order to reduce the requirements of this system, nanoengineering is the simple and efficient method to improve the thermodynamic properties and reduce kinetic barrier of reaction between LiBH4 and MgH2. Based on ab initio density functional theory (DFT) calculations, the previous study has indicated that the reaction between LiBH4 and MgH2 can take place at temperature near 200°C or below. However, the predictions have been shown to be inconsistent with many experiments. Therefore, it is the first time that our experiment using ball milling with aerosol spraying (BMAS) to prove the reaction between LiBH4 and MgH2 can happen during high energy ball milling at room temperature. Through this BMAS process we have found undoubtedly the formation of MgB 2 and LiH during ball milling of MgH2 while aerosol spraying of the LiBH4/THF solution. Aerosol nanoparticles from LiBH 4/THF solution leads to form Li2B12H12 during BMAS process. The Li2B12H12 formed then reacts with MgH2 in situ during ball milling to form MgB 2 and LiH. Discrete element modeling (DEM) is a useful tool to describe operation of various ball milling processes. EDEM is software based on DEM to predict power consumption, liner and media wear and mill output. In order to further improve the milling efficiency of BMAS process, EDEM is conducted to make analysis for complicated ball milling process. Milling speed and ball's filling ratio inside the canister as the variables are considered to determine the milling efficiency. The average and maximum

  14. Nanoporous polymers for hydrogen storage.

    PubMed

    Germain, Jonathan; Fréchet, Jean M J; Svec, Frantisek

    2009-05-01

    The design of hydrogen storage materials is one of the principal challenges that must be met before the development of a hydrogen economy. While hydrogen has a large specific energy, its volumetric energy density is so low as to require development of materials that can store and release it when needed. While much of the research on hydrogen storage focuses on metal hydrides, these materials are currently limited by slow kinetics and energy inefficiency. Nanostructured materials with high surface areas are actively being developed as another option. These materials avoid some of the kinetic and thermodynamic drawbacks of metal hydrides and other reactive methods of storing hydrogen. In this work, progress towards hydrogen storage with nanoporous materials in general and porous organic polymers in particular is critically reviewed. Mechanisms of formation for crosslinked polymers, hypercrosslinked polymers, polymers of intrinsic microporosity, and covalent organic frameworks are discussed. Strategies for controlling hydrogen storage capacity and adsorption enthalpy via manipulation of surface area, pore size, and pore volume are discussed in detail.

  15. Materials for hydrogen storage: current research trends and perspectives.

    PubMed

    van den Berg, Annemieke W C; Areán, Carlos Otero

    2008-02-14

    Storage and transport of hydrogen constitutes a key enabling technology for the advent of a hydrogen-based energy transition. Main research trends on hydrogen storage materials, including metal hydrides, porous adsorbents and hydrogen clathrates, are reviewed with a focus on recent developments and an appraisal of the challenges ahead. .

  16. Hydrogen storage composition and method

    DOEpatents

    Heung, Leung K; Wicks, George G.

    2003-01-01

    A hydrogen storage composition based on a metal hydride dispersed in an aerogel prepared by a sol-gel process. The starting material for the aerogel is an organometallic compound, including the alkoxysilanes, organometals of the form M(OR)x and MOxRy, where R is an alkyl group of the form C.sub.n H.sub.2n+1, M is an oxide-forming metal, n, x, and y are integers, and y is two less than the valence of M. A sol is prepared by combining the starting material, alcohol, water, and an acid. The sol is conditioned to the proper viscosity and a hydride in the form of a fine powder is added. The mixture is polymerized and dried under supercritical conditions. The final product is a composition having a hydride uniformly dispersed throughout an inert, stable and highly porous matrix. It is capable of absorbing up to 30 moles of hydrogen per kilogram at room temperature and pressure, rapidly and reversibly. Hydrogen absorbed by the composition can be readily be recovered by heat or evacuation.

  17. Hydrogen storage composition and method

    DOEpatents

    Wicks, G.G.; Heung, L.K.

    1994-01-01

    A hydrogen storage composition based on a metal hydride dispersed in an aerogel prepared by a sol-gel process. The starting material for the aerogel is an organometallic compound, including the alkoxysilanes, organometals of the form M(OR){sub X} where R is an organic ligand of the form C{sub n}H{sub 2n+1}, and organometals of the form MO{sub x}Ry where R is an alkyl group, where M is an oxide-forming metal, n, x and y are integers and y is two less than the valence of M. A sol is prepared by combining the starting material, alcohol, water, and an acid. The sol is conditioned to the proper viscosity and a hydride in the form of a fine powder is added. The mixture is polymerized and dried under supercritical conditions. The final product is a composition having a hydride uniformly dispersed throughout an inert, stable and highly porous matrix. It is capable of absorbing up to 30 motes of hydrogen per kilogram at room temperature and pressure, rapidly and reversibly. Hydrogen absorbed by the composition can be readily be recovered by heat or evacuation.

  18. Carbon nanotube materials from hydrogen storage

    SciTech Connect

    Dillon, A.C.; Bekkedahl, T.A.; Cahill, A.F.

    1995-09-01

    The lack of convenient and cost-effective hydrogen storage is a major impediment to wide scale use of hydrogen in the United States energy economy. Improvements in the energy densities of hydrogen storage systems, reductions in cost, and increased compatibility with available and forecasted systems are required before viable hydrogen energy use pathways can be established. Carbon-based hydrogen adsorption materials hold particular promise for meeting and exceeding the U.S. Department of Energy hydrogen storage energy density targets for transportation if concurrent increases in hydrogen storage capacity and carbon density can be achieved. These two goals are normally in conflict for conventional porous materials, but may be reconciled by the design and synthesis of new adsorbent materials with tailored pore size distributions and minimal macroporosity. Carbon nanotubes offer the possibility to explore new designs for adsorbents because they can be fabricated with small size distributions, and naturally tend to self-assemble by van der Waals forces. This year we report heats of adsorption for hydrogen on nanotube materials that are 2 and 3 times greater than for hydrogen on activated carbon. The hydrogen which is most strongly bound to these materials remains on the carbon surface to temperatures greater than 285 K. These results suggest that nanocapillary forces are active in stabilizing hydrogen on the surfaces of carbon nanotubes, and that optimization of the adsorbent will lead to effective storage at higher temperatures. In this paper we will also report on our activities which are targeted at understanding and optimizing the nucleation and growth of single wall nanotubes. These experiments were made possible by the development of a unique feedback control circuit which stabilized the plasma-arc during a synthesis run.

  19. Advanced chemical hydride-based hydrogen generation/storage system for fuel cell vehicles

    SciTech Connect

    Breault, R.W.; Rolfe, J.

    1998-08-01

    Because of the inherent advantages of high efficiency, environmental acceptability, and high modularity, fuel cells are potentially attractive power supplies. Worldwide concerns over clean environments have revitalized research efforts on developing fuel cell vehicles (FCV). As a result of intensive research efforts, most of the subsystem technology for FCV`s are currently well established. These include: high power density PEM fuel cells, control systems, thermal management technology, and secondary power sources for hybrid operation. For mobile applications, however, supply of hydrogen or fuel for fuel cell operation poses a significant logistic problem. To supply high purity hydrogen for FCV operation, Thermo Power`s Advanced Technology Group is developing an advanced hydrogen storage technology. In this approach, a metal hydride/organic slurry is used as the hydrogen carrier and storage media. At the point of use, high purity hydrogen will be produced by reacting the metal hydride/organic slurry with water. In addition, Thermo Power has conceived the paths for recovery and regeneration of the spent hydride (practically metal hydroxide). The fluid-like nature of the spent hydride/organic slurry will provide a unique opportunity for pumping, transporting, and storing these materials. The final product of the program will be a user-friendly and relatively high energy storage density hydrogen supply system for fuel cell operation. In addition, the spent hydride can relatively easily be collected at the pumping station and regenerated utilizing renewable sources, such as biomass, natural, or coal, at the central processing plants. Therefore, the entire process will be economically favorable and environmentally friendly.

  20. Electrochemical hydrogen storage alloys and batteries fabricated from Mg containing base alloys

    DOEpatents

    Ovshinsky, Stanford R.; Fetcenko, Michael A.

    1996-01-01

    An electrochemical hydrogen storage material comprising: (Base Alloy).sub.a M.sub.b where, Base Alloy is an alloy of Mg and Ni in a ratio of from about 1:2 to about 2:1, preferably 1:1; M represents at least one modifier element chosen from the group consisting of Co, Mn, Al, Fe, Cu, Mo, W, Cr, V, Ti, Zr, Sn, Th, Si, Zn, Li, Cd, Na, Pb, La, Mm, and Ca; b is greater than 0.5, preferably 2.5, atomic percent and less than 30 atomic percent; and a+b=100 atomic percent. Preferably, the at least one modifier is chosen from the group consisting of Co, Mn, Al, Fe, and Cu and the total mass of the at least one modifier element is less than 25 atomic percent of the final composition. Most preferably, the total mass of said at least one modifier element is less than 20 atomic percent of the final composition.

  1. Hydrogen storage systems from waste Mg alloys

    NASA Astrophysics Data System (ADS)

    Pistidda, C.; Bergemann, N.; Wurr, J.; Rzeszutek, A.; Møller, K. T.; Hansen, B. R. S.; Garroni, S.; Horstmann, C.; Milanese, C.; Girella, A.; Metz, O.; Taube, K.; Jensen, T. R.; Thomas, D.; Liermann, H. P.; Klassen, T.; Dornheim, M.

    2014-12-01

    The production cost of materials for hydrogen storage is one of the major issues to be addressed in order to consider them suitable for large scale applications. In the last decades several authors reported on the hydrogen sorption properties of Mg and Mg-based systems. In this work magnesium industrial wastes of AZ91 alloy and Mg-10 wt.% Gd alloy are used for the production of hydrogen storage materials. The hydrogen sorption properties of the alloys were investigated by means of volumetric technique, in situ synchrotron radiation powder X-ray diffraction (SR-PXD) and calorimetric methods. The measured reversible hydrogen storage capacity for the alloys AZ91 and Mg-10 wt.% Gd are 4.2 and 5.8 wt.%, respectively. For the Mg-10 wt.% Gd alloy, the hydrogenated product was also successfully used as starting reactant for the synthesis of Mg(NH2)2 and as MgH2 substitute in the Reactive Hydride Composite (RHC) 2LiBH4 + MgH2. The results of this work demonstrate the concrete possibility to use Mg alloy wastes for hydrogen storage purposes.

  2. Systems Engineering of Chemical Hydrogen Storage, Pressure Vessel and Balance of Plant for Onboard Hydrogen Storage

    SciTech Connect

    Brooks, Kriston P.; Simmons, Kevin L.; Weimar, Mark R.

    2014-09-02

    This is the annual report for the Hydrogen Storage Engineering Center of Excellence project as required by DOE EERE's Fuel Cell Technologies Office. We have been provided with a specific format. It describes the work that was done with cryo-sorbent based and chemical-based hydrogen storage materials. Balance of plant components were developed, proof-of-concept testing performed, system costs estimated, and transient models validated as part of this work.

  3. Investigation and characterization of ball-milled magnesium-based hydrides for hydrogen storage materials

    NASA Astrophysics Data System (ADS)

    Yang, Jing

    2011-12-01

    Three alloys are prepared through mechanical alloying and the hydrogen storage properties have been investigated systematically. In Mg-Ni and Mg-Ni-Fe alloys, the main binary alloy phase is Mg2Ni, while in Mg-Ni-Fe-Ti alloys, NiTi, FeTi are also found as the main binary phases beside Mg 2Ni. The hydrogen absorption capacities of the three alloys are 2.9wt%, 2.2wt% and 2.3wt% respectively. Absorption content increases with the increasing of milling time, which also increases the amorphous degree of the alloys. The amorphous degree increasing is unfavorable to improve hydrogen storage capacity. Longer milling time will contribute to a higher hydriding/dehydriding rate at a constant temperature. The alloys exhibit a different hydriding behavior when temperature was increased from 473K to 673K. The alloys particles became finer after long time milling, which led to a decrease in the different distance of the hydrogen atoms.

  4. HGMS: Glasses and Nanocomposites for Hydrogen Storage.

    SciTech Connect

    Lipinska, Kris; Hemmers, Oliver

    2013-02-17

    The primary goal of this project is to fabricate and investigate different glass systems and glass-derived nanocrystalline composite materials. These glass-based, two-phased materials will contain nanocrystals that can attract hydrogen and be of potential interest as hydrogen storage media. The glass materials with intrinsic void spaces that are able to precipitate functional nanocrystals capable to attract hydrogen are of particular interest. Proposed previously, but never practically implemented, one of promising concepts for storing hydrogen are micro-containers built of glass and shaped into hollow microspheres. The project expanded this concept to the exploration of glass-derived nanocrystalline composites as potential hydrogen storage media. It is known that the most desirable materials for hydrogen storage do not interact chemically with hydrogen and possess a high surface area to host substantial amounts of hydrogen. Glasses are built of disordered networks with ample void spaces that make them permeable to hydrogen even at room temperature. Glass-derived nanocrystalline composites (two-phased materials), combination of glasses (networks with ample voids) and functional nanocrystals (capable to attract hydrogen), appear to be promising candidates for hydrogen storage media. Key advantages of glass materials include simplicity of preparation, flexibility of composition, chemical durability, non-toxicity and mechanical strength, as well as low production costs and environmental friendliness. This project encompasses a fundamental research into physics and chemistry of glasses and nanocrystalline composite materials, derived from glass. Studies are aimed to answer questions essential for considering glass-based materials and composites as potential hydrogen storage media. Of particular interest are two-phased materials that combine glasses with intrinsic voids spaces for physisorption of hydrogen and nanocrystals capable of chemisorption. This project does not

  5. Hydrogen storage development

    SciTech Connect

    Thomas, G.J.; Guthrie, S.E.

    1998-08-01

    A summary of the hydride development efforts for the current program year (FY98) are presented here. The Mg-Al-Zn alloy system was studied at low Zn levels (2--4 wt%) and midrange Al contents (40--60 wt%). Higher plateau pressures were found with Al and Zn alloying in Mg and, furthermore, it was found that the hydrogen desorption kinetics were significantly improved with small additions of Zn. Results are also shown here for a detailed study of the low temperature properties of Mg{sub 2}NiH{sub 4}, and a comparison made between conventional melt cast alloy and the vapor process material.

  6. First Principles Based Simulation of Reaction-Induced Phase Transition in Hydrogen Storage and Other Materials

    SciTech Connect

    Ge, Qingfeng

    2014-08-31

    This major part of this proposal is simulating hydrogen interactions in the complex metal hydrides. Over the period of DOE BES support, key achievements include (i) Predicted TiAl3Hx as a precursor state for forming TiAl3 through analyzing the Ti-doped NaAlH4 and demonstrated its catalytic role for hydrogen release; (ii) Explored the possibility of forming similar complex structures with other 3d transition metals in NaAlH4 as well as the impact of such complex structures on hydrogen release/uptake; (iii) Demonstrated the role of TiAl3 in hydriding process; (iv) Predicted a new phase of NaAlH4 that links to Na3AlH6 using first-principles metadynamics; (v) Examined support effect on hydrogen release from supported/encapsulated NaAlH4; and (vi) Expanded research scope beyond hydrogen storage. The success of our research is documented by the peer-reviewed publications.

  7. Proceedings of the DOE chemical energy storage and hydrogen energy systems contracts review

    SciTech Connect

    Not Available

    1980-02-01

    Sessions were held on electrolysis-based hydrogen storage systems, hydrogen production, hydrogen storage systems, hydrogen storage materials, end-use applications and system studies, chemical heat pump/chemical energy storage systems, systems studies and assessment, thermochemical hydrogen production cycles, advanced production concepts, and containment materials. (LHK)

  8. Hydrogen storage via polyhydride complexes

    SciTech Connect

    Jensen, C.M.

    1996-10-01

    Polyhydride metal complexes are being developed for application to hydrogen storage. Complexes have been found which catalyze the reversible hydrogenation of unsaturated hydrocarbons. This catalytic reaction could be the basis for a low temperature, hydrogen storage system with a available hydrogen density greater than 7 weight percent. The P-C-P pincer complexes, RhH{sub 2}(C{sub 6}H{sub 3}-2,6-(CH{sub 2}PBu{sup t}{sub 2}){sub 2}) and IrH{sub 2}(C{sub 6}H{sub 3}-2,6-(CH{sub 2}PBu{sup t}{sub 2}){sub 2}) have unprecedented, long term stability at elevated temperatures. The novel iridium complex catalyzes the transfer dehydrogenation of cycloctane to cyclooctene at the rate of 716 turnovers/h which is 2 orders of magnitude greater than that found for previously reported catalytic systems which do not require the sacrificial hydrogenation of a large excess of hydrogen acceptor.

  9. Hydrogen storage on activated carbon. Final report

    SciTech Connect

    Schwarz, J.A.

    1994-11-01

    The project studied factors that influence the ability of carbon to store hydrogen and developed techniques to enhance that ability in naturally occurring and factory-produced commercial carbon materials. During testing of enhanced materials, levels of hydrogen storage were achieved that compare well with conventional forms of energy storage, including lead-acid batteries, gasoline, and diesel fuel. Using the best materials, an electric car with a modern fuel cell to convert the hydrogen directly to electricity would have a range of over 1,000 miles. This assumes that the total allowable weight of the fuel cell and carbon/hydrogen storage system is no greater than the present weight of batteries in an existing electric vehicle. By comparison, gasoline cars generally are limited to about a 450-mile range, and battery-electric cars to 40 to 60 miles. The project also developed a new class of carbon materials, based on polymers and other organic compounds, in which the best hydrogen-storing factors discovered earlier were {open_quotes}molecularly engineered{close_quotes} into the new materials. It is believed that these new molecularly engineered materials are likely to exceed the performance of the naturally occurring and manufactured carbons seen earlier with respect to hydrogen storage.

  10. Hydrogen storage properties of a Ni, Fe and Ti-added Mg-based alloy

    NASA Astrophysics Data System (ADS)

    Song, Myoung Youp; Kwon, Sung Nam; Hong, Seong-Hyeon; Park, Hye Ryoung

    2012-04-01

    Mg-5wt%Ni-2.5wt%Fe-2.5wt%Ti (referred to as Mg-5Ni-2.5Fe-2.5Ti) hydrogen storage material was prepared by reactive mechanical grinding, after which the hydrogen absorption and desorption kinetics were investigated using a Sievert-type volumetric apparatus. A nanocrystalline Mg-5Ni-2.5Fe-2.5Ti sample was prepared by reactive mechanical grinding and hydriding-dehydriding cycling. Analysis by the Williamson-Hall method from an XRD pattern of this sample after 10 hydriding-dehydriding cycles showed that the crystallite size of Mg was 37.0 nm and that its strain was 0.0407%. The activation of Mg-5Ni-2.5Fe-2.5Ti was completed after three hydriding-dehydriding cycles. The prepared Mg-5Ni-2.5Fe-2.5Ti sample had an effective hydrogen-storage capacity near 5 wt% H. The activated Mg-5Ni-2.5Fe-2.5Ti sample absorbed 4.37 and 4.90 wt% H for 5 and 60 min, respectively, at 593K under 12 bar H2, and desorbed 1.69, 3.81, and 4.85 wt% H for 5, 10 and 60 min, respectively, at 593K under 1.0 bar H2.

  11. System level analysis of hydrogen storage options.

    SciTech Connect

    Ahluwalia, R. K.; Peng, J.-C.; Hua, T. Q.; Kumar, R.; Satyapal, S.; USDOE

    2006-01-01

    The overall objective of this effort is to support DOE with independent system level analyses of various H2 storage approaches, to help to assess and down-select options, and to determine the feasibility of meeting DOE targets. Specific objectives in Fiscal Year 2008 included: (1) Model various developmental hydrogen storage systems, (2) Provide results to Centers of Excellence (CoEs) for assessment of performance targets and goals, (3) Develop models to 'reverse-engineer' particular approaches, (4) Identify interface issues, opportunities, and data needs for technology development. Several different approaches are being pursued to develop on-board hydrogen storage systems with the goal of meeting DOE targets for light-duty vehicular applications. Each approach has unique characteristics, such as the thermal energy and temperature of charge and discharge, kinetics of the physical and chemical process steps involved, and requirements for the materials and energy interfaces between the storage system and the fuel supply system on the one hand, and the fuel user on the other. Other storage system design and operating parameters influence the projected system costs as well. We are developing models to understand the characteristics of storage systems based on these approaches and to evaluate their potential to meet the DOE targets for on-board applications. Our approach is to develop thermodynamic, kinetic, and engineering models of the various hydrogen storage systems being developed under DOE sponsorship.

  12. Final Report: Metal Perhydrides for Hydrogen Storage

    SciTech Connect

    Hwang, J-Y.; Shi, S.; Hackney, S.; Swenson, D.; Hu, Y.

    2011-07-26

    H molecule contains one hydrogen atom because the valence of a Li ion is +1. One MgH2 molecule contains two hydrogen atoms because the valence of a Mg ion is +2. In metal perhydrides, a molecule could contain more hydrogen atoms than expected based on the metal valance, i.e. LiH1+n and MgH2+n (n is equal to or greater than 1). When n is sufficiently high, there will be plenty of hydrogen storage capacity to meet future requirements. The existence of hydrogen clusters, Hn+ (n = 5, 7, 9, 11, 13, 15) and transition metal ion-hydrogen clusters, M+(H2)n (n = 1-6), such as Sc(H2)n+, Co(H2)n+, etc., have assisted the development of this concept. Clusters are not stable species. However, their existence stimulates our approach on using electric charges to enhance the hydrogen adsorption in a hydrogen storage system in this study. The experimental and modeling work to verify it are reported here. Experimental work included the generation of cold hydrogen plasma through a microwave approach, synthesis of sorbent materials, design and construction of lab devices, and the determination of hydrogen adsorption capacities on various sorbent materials under various electric field potentials and various temperatures. The results consistently show that electric potential enhances the adsorption of hydrogen on sorbents. NiO, MgO, activated carbon, MOF, and MOF and platinum coated activated carbon are some of the materials studied. Enhancements up to a few hundred percents have been found. In general, the enhancement increases with the electrical potential, the pressure applied, and the temperature lowered. Theoretical modeling of the hydrogen adsorption on the sorbents under the electric potential has been investigated with the density functional theory (DFT) approach. It was found that the interaction energy between hydrogen and sorbent is increased remarkably when an electric field is applied. This increase of binding energy offers a potential solution for DOE when looking for a compromise

  13. High capacity hydrogen storage nanocomposite materials

    DOEpatents

    Zidan, Ragaiy; Wellons, Matthew S

    2015-02-03

    A novel hydrogen absorption material is provided comprising a mixture of a lithium hydride with a fullerene. The subsequent reaction product provides for a hydrogen storage material which reversibly stores and releases hydrogen at temperatures of about 270.degree. C.

  14. A composite of complex and chemical hydrides yields the first Al-based amidoborane with improved hydrogen storage properties.

    PubMed

    Dovgaliuk, Iurii; Jepsen, Lars H; Safin, Damir A; Łodziana, Zbigniew; Dyadkin, Vadim; Jensen, Torben R; Devillers, Michel; Filinchuk, Yaroslav

    2015-10-05

    The first Al-based amidoborane Na[Al(NH2 BH3 )4 ] was obtained through a mechanochemical treatment of the NaAlH4 -4 AB (AB=NH3 BH3 ) composite releasing 4.5 wt % of pure hydrogen. The same amidoborane was also produced upon heating the composite at 70 °C. The crystal structure of Na[Al(NH2 BH3 )4 ], elucidated from synchrotron X-ray powder diffraction and confirmed by DFT calculations, contains the previously unknown tetrahedral ion [Al(NH2 BH3 )4 ](-) , with every NH2 BH3 (-) ligand coordinated to aluminum through nitrogen atoms. Combination of complex and chemical hydrides in the same compound was possible due to both the lower stability of the AlH bonds compared to the BH ones in borohydride, and due to the strong Lewis acidity of Al(3+) . According to the thermogravimetric analysis-differential scanning calorimetry-mass spectrometry (TGA-DSC-MS) studies, Na[Al(NH2 BH3 )4 ] releases in two steps 9 wt % of pure hydrogen. As a result of this decomposition, which was also supported by volumetric studies, the formation of NaBH4 and amorphous product(s) of the surmised composition AlN4 B3 H(0-3.6) were observed. Furthermore, volumetric experiments have also shown that the final residue can reversibly absorb about 27 % of the released hydrogen at 250 °C and p(H2 )=150 bar. Hydrogen re-absorption does not regenerate neither Na[Al(NH2 BH3 )4 ] nor starting materials, NaAlH4 and AB, but rather occurs within amorphous product(s). Detailed studies of the latter one(s) can open an avenue for a new family of reversible hydrogen storage materials. Finally, the NaAlH4 -4 AB composite might become a starting point towards a new series of aluminum-based tetraamidoboranes with improved hydrogen storage properties such as hydrogen storage density, hydrogen purity, and reversibility. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Composition and method for hydrogen storage

    NASA Technical Reports Server (NTRS)

    Mao, Wendy L. (Inventor); Mao, Ho-Kwang (Inventor)

    2004-01-01

    A method for hydrogen storage includes providing water and hydrogen gas to a containment volume, reducing the temperature of the water and hydrogen gas to form a hydrogen clathrate at a first cryogenic temperature and a first pressure and maintaining the hydrogen clathrate at second cryogenic temperature within a temperature range of up to 250 K to effect hydrogen storage. The low-pressure hydrogen hydrate includes H.sub.2 O molecules, H.sub.2 molecules and a unit cell including polyhedron cages of hydrogen-bonded frameworks of the H.sub.2 O molecules built around the H.sub.2 molecules.

  16. Superior hydrogen storage in high entropy alloys

    PubMed Central

    Sahlberg, Martin; Karlsson, Dennis; Zlotea, Claudia; Jansson, Ulf

    2016-01-01

    Metal hydrides (MHx) provide a promising solution for the requirement to store large amounts of hydrogen in a future hydrogen-based energy system. This requires the design of alloys which allow for a very high H/M ratio. Transition metal hydrides typically have a maximum H/M ratio of 2 and higher ratios can only be obtained in alloys based on rare-earth elements. In this study we demonstrate, for the first time to the best of our knowledge, that a high entropy alloy of TiVZrNbHf can absorb much higher amounts of hydrogen than its constituents and reach an H/M ratio of 2.5. We propose that the large hydrogen-storage capacity is due to the lattice strain in the alloy that makes it favourable to absorb hydrogen in both tetrahedral and octahedral interstitial sites. This observation suggests that high entropy alloys have future potential for use as hydrogen storage materials. PMID:27829659

  17. Nanomaterials for Hydrogen Storage Applications: A Review

    DOE PAGES

    Niemann, Michael U.; Srinivasan, Sesha S.; Phani, Ayala R.; ...

    2008-01-01

    Nmore » anomaterials have attracted great interest in recent years because of the unusual mechanical, electrical, electronic, optical, magnetic and surface properties. The high surface/volume ratio of these materials has significant implications with respect to energy storage. Both the high surface area and the opportunity for nanomaterial consolidation are key attributes of this new class of materials for hydrogen storage devices.anostructured systems including carbon nanotubes, nano-magnesium based hydrides, complex hydride/carbon nanocomposites, boron nitride nanotubes, TiS 2 / MoS 2 nanotubes, alanates, polymer nanocomposites, and metal organic frameworks are considered to be potential candidates for storing large quantities of hydrogen. Recent investigations have shown that nanoscale materials may offer advantages if certain physical and chemical effects related to the nanoscale can be used efficiently. The present review focuses the application of nanostructured materials for storing atomic or molecular hydrogen. The synergistic effects of nanocrystalinity and nanocatalyst doping on the metal or complex hydrides for improving the thermodynamics and hydrogen reaction kinetics are discussed. In addition, various carbonaceous nanomaterials and novel sorbent systems (e.g. carbon nanotubes, fullerenes, nanofibers, polyaniline nanospheres and metal organic frameworks etc.) and their hydrogen storage characteristics are outlined.« less

  18. Modeling leaks from liquid hydrogen storage systems.

    SciTech Connect

    Winters, William Stanley, Jr.

    2009-01-01

    This report documents a series of models for describing intended and unintended discharges from liquid hydrogen storage systems. Typically these systems store hydrogen in the saturated state at approximately five to ten atmospheres. Some of models discussed here are equilibrium-based models that make use of the NIST thermodynamic models to specify the states of multiphase hydrogen and air-hydrogen mixtures. Two types of discharges are considered: slow leaks where hydrogen enters the ambient at atmospheric pressure and fast leaks where the hydrogen flow is usually choked and expands into the ambient through an underexpanded jet. In order to avoid the complexities of supersonic flow, a single Mach disk model is proposed for fast leaks that are choked. The velocity and state of hydrogen downstream of the Mach disk leads to a more tractable subsonic boundary condition. However, the hydrogen temperature exiting all leaks (fast or slow, from saturated liquid or saturated vapor) is approximately 20.4 K. At these temperatures, any entrained air would likely condense or even freeze leading to an air-hydrogen mixture that cannot be characterized by the REFPROP subroutines. For this reason a plug flow entrainment model is proposed to treat a short zone of initial entrainment and heating. The model predicts the quantity of entrained air required to bring the air-hydrogen mixture to a temperature of approximately 65 K at one atmosphere. At this temperature the mixture can be treated as a mixture of ideal gases and is much more amenable to modeling with Gaussian entrainment models and CFD codes. A Gaussian entrainment model is formulated to predict the trajectory and properties of a cold hydrogen jet leaking into ambient air. The model shows that similarity between two jets depends on the densimetric Froude number, density ratio and initial hydrogen concentration.

  19. Hydride development for hydrogen storage

    SciTech Connect

    Thomas, G.J.; Guthrie, S.E.; Bauer, W.; Yang, N.Y.C.; Sandrock, G.

    1996-10-01

    The purpose of this project is to develop and demonstrate improved hydride materials for hydrogen storage. The work currently is organized into four tasks: hydride development, bed fabrication, materials support for engineering systems, and IEA Annex 12 activities. At the present time, hydride development is focused on Mg alloys. These materials generally have higher weight densities for storing hydrogen than rare earth or transition metal alloys, but suffer from high operating temperatures, slow kinetic behavior and material stability. The authors approach is to study bulk alloy additions which increase equilibrium overpressure, in combination with stable surface alloy modification and particle size control to improve kinetic properties. This work attempts to build on the considerable previous research in this area, but examines specific alloy systems in greater detail, with attention to known phase properties and structures. The authors have found that specific phases can be produced which have significantly improved hydride properties compared to previous studies.

  20. Hydrogen Fuel Cells and Storage Technology: Fundamental Research for Optimization of Hydrogen Storage and Utilization

    SciTech Connect

    Perret, Bob; Heske, Clemens; Nadavalath, Balakrishnan; Cornelius, Andrew; Hatchett, David; Bae, Chusung; Pang, Tao; Kim, Eunja; Hemmers, Oliver

    2011-03-28

    Design and development of improved low-cost hydrogen fuel cell catalytic materials and high-capacity hydrogenn storage media are paramount to enabling the hydrogen economy. Presently, effective and durable catalysts are mostly precious metals in pure or alloyed form and their high cost inhibits fuel cell applications. Similarly, materials that meet on-board hydrogen storage targets within total mass and volumetric constraints are yet to be found. Both hydrogen storage performance and cost-effective fuel cell designs are intimately linked to the electronic structure, morphology and cost of the chosen materials. The FCAST Project combined theoretical and experimental studies of electronic structure, chemical bonding, and hydrogen adsorption/desorption characteristics of a number of different nanomaterials and metal clusters to develop better fundamental understanding of hydrogen storage in solid state matrices. Additional experimental studies quantified the hydrogen storage properties of synthesized polyaniline(PANI)/Pd composites. Such conducting polymers are especially interesting because of their high intrinsic electron density and the ability to dope the materials with protons, anions, and metal species. Earlier work produced contradictory results: one study reported 7% to 8% hydrogen uptake while a second study reported zero hydrogen uptake. Cost and durability of fuel cell systems are crucial factors in their affordability. Limits on operating temperature, loss of catalytic reactivity and degradation of proton exchange membranes are factors that affect system durability and contribute to operational costs. More cost effective fuel cell components were sought through studies of the physical and chemical nature of catalyst performance, characterization of oxidation and reduction processes on system surfaces. Additional development effort resulted in a new hydrocarbon-based high-performance sulfonated proton exchange membrane (PEM) that can be manufactured at low

  1. Chemical and physical solutions for hydrogen storage.

    PubMed

    Eberle, Ulrich; Felderhoff, Michael; Schüth, Ferdi

    2009-01-01

    Hydrogen is a promising energy carrier in future energy systems. However, storage of hydrogen is a substantial challenge, especially for applications in vehicles with fuel cells that use proton-exchange membranes (PEMs). Different methods for hydrogen storage are discussed, including high-pressure and cryogenic-liquid storage, adsorptive storage on high-surface-area adsorbents, chemical storage in metal hydrides and complex hydrides, and storage in boranes. For the latter chemical solutions, reversible options and hydrolytic release of hydrogen with off-board regeneration are both possible. Reforming of liquid hydrogen-containing compounds is also a possible means of hydrogen generation. The advantages and disadvantages of the different systems are compared.

  2. Hydrogen storage and integrated fuel cell assembly

    DOEpatents

    Gross, Karl J.

    2010-08-24

    Hydrogen is stored in materials that absorb and desorb hydrogen with temperature dependent rates. A housing is provided that allows for the storage of one or more types of hydrogen-storage materials in close thermal proximity to a fuel cell stack. This arrangement, which includes alternating fuel cell stack and hydrogen-storage units, allows for close thermal matching of the hydrogen storage material and the fuel cell stack. Also, the present invention allows for tailoring of the hydrogen delivery by mixing different materials in one unit. Thermal insulation alternatively allows for a highly efficient unit. Individual power modules including one fuel cell stack surrounded by a pair of hydrogen-storage units allows for distribution of power throughout a vehicle or other electric power consuming devices.

  3. Graphene-based materials: fabrication, characterization and application for the decontamination of wastewater and wastegas and hydrogen storage/generation.

    PubMed

    Wang, Hou; Yuan, Xingzhong; Wu, Yan; Huang, Huajun; Peng, Xin; Zeng, Guangming; Zhong, Hua; Liang, Jie; Ren, Miaomiao

    2013-07-01

    Graphene, as an ideal two-dimensional material and single-atom layer of graphite, has attracted exploding interests in multidisciplinary research because of its unique structure and exceptional physicochemical properties. Especially, graphene-based materials offer a wide range of potentialities for environmental remediation and energy applications. This review shows an extensive overview of the main principles and the recent synthetic technologies about designing and fabricating various innovative graphene-based materials. Furthermore, an extensive list of graphene-based sorbents and catalysts from vast literature has been compiled. The adsorptive and catalytic properties of graphene-based materials for the removal of various pollutants and hydrogen storage/production as available in the literature are presented. Tremendous adsorption capacity, excellent catalytic performance and abundant availability are the significant factors making these materials suitable alternatives for environmental pollutant control and energy-related system, especially in terms of the removal of pollutants in water, gas cleanup and purification, and hydrogen generation and storage. Meanwhile, a brief discussion is also included on the influence of graphene materials on the environment, and its toxicological effects. Lastly, some unsolved subjects together with major challenges in this germinating area of research are highlighted and discussed. Conclusively, the expanding of graphene-based materials in the field of adsorption and catalysis science represents a viable and powerful tool, resulting in the superior improvement of environmental pollution control and energy development.

  4. High surface area microporous carbon materials for cryogenic hydrogen storage synthesized using new template-based and activation-based approaches.

    PubMed

    Meisner, Gregory P; Hu, Qingyuan

    2009-05-20

    High surface area microporous carbon materials were synthesized using new, simple, and innovative approaches based on traditional template and chemical activation methods. The resulting surface area and porosity were characterized using Brunauer-Emmett-Teller (BET)-type measurements and analysis, and the hydrogen storage capacity was determined using excess hydrogen adsorption measurements at 77 K and up to 40 bar hydrogen pressure. For our direct one-step aerosol-assisted template-based synthesis method of mixing the template precursor and carbon precursor solutions, a specific surface area value of up to nearly 2000 m(2) g(-1) and an excess hydrogen storage capacity of 4.2 wt% was observed. For our chemical activation-based synthesis method of homogeneously mixing the chemical activation reagent into the carbon precursor solution, a specific surface area value of nearly 3000 m(2) g(-1) and an excess hydrogen adsorption capacity of nearly 5.8 wt% were observed. The surface area and hydrogen uptake results varied systematically with the synthesis parameters, and we observed a strong correlation between the BET values of the specific surface area and the excess hydrogen adsorption capacity.

  5. Nickel hydrogen battery cell storage matrix test

    NASA Technical Reports Server (NTRS)

    Wheeler, James R.; Dodson, Gary W.

    1993-01-01

    Test were conducted to evaluate post storage performance of nickel hydrogen cells with various design variables, the most significant being nickel precharge versus hydrogen precharge. Test procedures and results are presented in outline and graphic form.

  6. Pd doped reduced graphene oxide for hydrogen storage

    NASA Astrophysics Data System (ADS)

    Das, Tapas; Banerjee, Seemita; Sudarsan, V.

    2015-06-01

    Pd nanoparticles dispersed reduced graphene oxide sample has been prepared by a simple chemical method using hydrazine as the reducing agent. Based on XRD and 13C MAS NMR studies it is confirmed that, Pd nanoparticles are effectively mixed with the reduced graphene oxide sample. Maximum hydrogen storage capacity has been estimated to be ˜1.36 wt % at 123K. Improved hydrogen storage capacity of Pd incorporated sample can be explained based on the phenomenon of spillover of atomic hydrogen.

  7. Pd doped reduced graphene oxide for hydrogen storage

    SciTech Connect

    Das, Tapas; Banerjee, Seemita; Sudarsan, V.

    2015-06-24

    Pd nanoparticles dispersed reduced graphene oxide sample has been prepared by a simple chemical method using hydrazine as the reducing agent. Based on XRD and {sup 13}C MAS NMR studies it is confirmed that, Pd nanoparticles are effectively mixed with the reduced graphene oxide sample. Maximum hydrogen storage capacity has been estimated to be ∼1.36 wt % at 123K. Improved hydrogen storage capacity of Pd incorporated sample can be explained based on the phenomenon of spillover of atomic hydrogen.

  8. Hydrogen Storage in Metal-Organic Frameworks

    SciTech Connect

    Omar M. Yaghi

    2012-04-26

    Conventional storage of large amounts of hydrogen in its molecular form is difficult and expensive because it requires employing either extremely high pressure gas or very low temperature liquid. Because of the importance of hydrogen as a fuel, the DOE has set system targets for hydrogen storage of gravimetric (5.5 wt%) and volumetric (40 g L-1) densities to be achieved by 2015. Given that these are system goals, a practical material will need to have higher capacity when the weight of the tank and associated cooling or regeneration system is considered. The size and weight of these components will vary substantially depending on whether the material operates by a chemisorption or physisorption mechanism. In the latter case, metal-organic frameworks (MOFs) have recently been identified as promising adsorbents for hydrogen storage, although little data is available for their sorption behavior. This grant was focused on the study of MOFs with these specific objectives. (1) To examine the effects of functionalization, catenation, and variation of the metal oxide and organic linkers on the low-pressure hydrogen adsorption properties of MOFs. (2) To develop a strategy for producing MOFs with high surface area and porosity to reduce the dead space and increase the hydrogen storage capacity per unit volume. (3) To functionalize MOFs by post synthetic functionalization with metals to improve the adsorption enthalpy of hydrogen for the room temperature hydrogen storage. This effort demonstrated the importance of open metal sites to improve the adsorption enthalpy by the systematic study, and this is also the origin of the new strategy, which termed isoreticular functionalization and metalation. However, a large pore volume is still a prerequisite feature. Based on our principle to design highly porous MOFs, guest-free MOFs with ultrahigh porosity have been experimentally synthesized. MOF-210, whose BET surface area is 6240 m2 g-1 (the highest among porous solids), takes up

  9. Hydrogen Storage for Aircraft Applications Overview

    NASA Technical Reports Server (NTRS)

    Colozza, Anthony J.; Kohout, Lisa (Technical Monitor)

    2002-01-01

    Advances in fuel cell technology have brought about their consideration as sources of power for aircraft. This power can be utilized to run aircraft systems or even provide propulsion power. One of the key obstacles to utilizing fuel cells on aircraft is the storage of hydrogen. An overview of the potential methods of hydrogen storage was compiled. This overview identifies various methods of hydrogen storage and points out their advantages and disadvantages relative to aircraft applications. Minimizing weight and volume are the key aspects to storing hydrogen within an aircraft. An analysis was performed to show how changes in certain parameters of a given storage system affect its mass and volume.

  10. In Pursuit of Sustainable Hydrogen Storage with Boron-Nitride Fullerene as the Storage Medium.

    PubMed

    Ganguly, Gaurab; Malakar, Tanmay; Paul, Ankan

    2016-06-22

    Using well calibrated DFT studies we predict that experimentally synthesized B24 N24 fullerene can serve as a potential reversible chemical hydrogen storage material with hydrogen-gas storage capacity up to 5.13 wt %. Our theoretical studies show that hydrogenation and dehydrogenation of the fullerene framework can be achieved at reasonable rates using existing metal-free hydrogenating agents and base metal-containing dehydrogenation catalysts.

  11. Hydrogen storage in engineered carbon nanospaces.

    PubMed

    Burress, Jacob; Kraus, Michael; Beckner, Matt; Cepel, Raina; Suppes, Galen; Wexler, Carlos; Pfeifer, Peter

    2009-05-20

    It is shown how appropriately engineered nanoporous carbons provide materials for reversible hydrogen storage, based on physisorption, with exceptional storage capacities (approximately 80 g H2/kg carbon, approximately 50 g H2/liter carbon, at 50 bar and 77 K). Nanopores generate high storage capacities (a) by having high surface area to volume ratios, and (b) by hosting deep potential wells through overlapping substrate potentials from opposite pore walls, giving rise to a binding energy nearly twice the binding energy in wide pores. Experimental case studies are presented with surface areas as high as 3100 m(2) g(-1), in which 40% of all surface sites reside in pores of width approximately 0.7 nm and binding energy approximately 9 kJ mol(-1), and 60% of sites in pores of width>1.0 nm and binding energy approximately 5 kJ mol(-1). The findings, including the prevalence of just two distinct binding energies, are in excellent agreement with results from molecular dynamics simulations. It is also shown, from statistical mechanical models, that one can experimentally distinguish between the situation in which molecules do (mobile adsorption) and do not (localized adsorption) move parallel to the surface, how such lateral dynamics affects the hydrogen storage capacity, and how the two situations are controlled by the vibrational frequencies of adsorbed hydrogen molecules parallel and perpendicular to the surface: in the samples presented, adsorption is mobile at 293 K, and localized at 77 K. These findings make a strong case for it being possible to significantly increase hydrogen storage capacities in nanoporous carbons by suitable engineering of the nanopore space.

  12. The borohydride oxidation reaction on La-Ni-based hydrogen-storage alloys.

    PubMed

    Paschoalino, Waldemir J; Thompson, Stephen J; Russell, Andrea E; Ticianelli, Edson A

    2014-07-21

    This work provides insights into the processes involved in the borohydride oxidation reaction (BOR) in alkaline media on metal hydride alloys formed by LaNi(4.7)Sn(0.2)Cu(0.1) and LaNi(4.78)Al(0.22) with and without deposited Pt, Pd, and Au. The results confirm the occurrence of hydrolysis of the borohydride ions when the materials are exposed to BH(4)(-) and a continuous hydriding of the alloys during BH(4)(-) oxidation measurements at low current densities. The activity for the direct BOR is low in both bare metal hydride alloys, but the rate of the BH(4)(-) hydrolysis and the hydrogen-storage capacity are higher, while the rate of H diffusion is slower for bare LaNi(4.78) Al(0.22). The addition of Pt and Pd to both alloys results in an increase of the BH(4)(-) hydrolysis, but the H(2) formed is rapidly oxidized at the Pt-modified catalysts. In the case of Au modification, a small increase in the BH(4)(-) hydrolysis is observed as compared to the bare alloys. The presence of Au and Pd also leads to a reduction of the rates of alloy hydriding/de-hydriding.

  13. Designing carbon nanoframeworks tailored for hydrogen storage

    NASA Astrophysics Data System (ADS)

    Weck, Philippe F.; Kim, Eunja; Balakrishnan, Naduvalath; Cheng, Hansong; Yakobson, Boris I.

    2007-05-01

    Based on first-principles calculations, we propose a novel class of 3-D materials consisting of small diameter single-walled carbon nanotubes (SWCNTs) functionalized by organic ligands as potential hydrogen storage media. Specifically, we have carried out density functional theory calculations to determine the stable structures and properties of nanoframeworks consisting of (5, 0) and (3, 3) SWCNTs constrained by phenyl spacers. Valence and conduction properties, as well as normal modes, of pristine nanotubes are found to change significantly upon functionalization, in a way that can serve as experimental diagnostics of the successful synthesis of the proposed framework structures. Ab initio molecular dynamics simulations indicate that such systems are thermodynamically stable for on-board hydrogen storage.

  14. Study on Hydrogen Storage Materials

    NASA Astrophysics Data System (ADS)

    Sugiyama, Jun

    2016-09-01

    Complex hydrides have been heavily investigated as a hydrogen storage material, particularly for future vehicular applications. The present major problem of such complex hydrides is their relatively high hydrogen desorption temperature (Td). In order to find a predominant parameter for determining Td, we have investigated internal nuclear magnetic fields in several complex hydrides, such as, lithium and sodium alanates, borohydrides, and magnesium hydrides, with a muon spin rotation and relaxation (μ+SR) technique. At low temperatures, the μ+SR spectrum obtained in a zero external field (ZF) exhibits a clear oscillation due to the formation of a three spin 1/2 system, HμH, besides Mg(BH4)2 and Sc(BH4)2. Such oscillatory signal becomes weaker and weaker with increasing temperature, and finally disappears above around room temperature. However, the volume fraction of the HμH signal to the whole asymmetry at 5 K is found to be a good indicator for Td in borohydrides. At high temperatures, on the contrary, the ZF-spectrum for MgH2 shows a Kubo-Toyabe like relaxation due to a random nuclear magnetic field of 1H. Such nuclear magnetic field becomes dynamic well below Td in the milled MgH2, indicating a significant role on H-diffusion in solids for determining Td.

  15. Hydrogen-rich boron-containing materials for hydrogen storage.

    PubMed

    Wang, Ping; Kang, Xiang-Dong

    2008-10-28

    Hydrogen-rich boron-containing compounds have received extensive attention as potential hydrogen storage media for vehicular applications. The past years have seen significant progresses in material discovery, material composition/structure tailoring, catalyst identification and regeneration chemistry, which give rise to state-of-the-art hydrogen storage materials/technologies. Lithium tetrahydroborate-related materials exhibit the hitherto highest reversible hydrogen capacity via solid-gas reactions. Catalytic hydrolysis of sodium tetrahydroborate offers an on-demand hydrogen generation system for vehicular applications. Ammonia borane-related materials exhibit a satisfactory combination of material properties that are suited for on-board hydrogen sources, coupled with significant advances in spent fuels regeneration. This Perspective discusses the current progresses of these representative reversible or irreversible material systems, aiming at providing an outline of the forefront of hydrogen storage materials/technologies for transportation applications.

  16. EDITORIAL: Nanoscale phenomena in hydrogen storage Nanoscale phenomena in hydrogen storage

    NASA Astrophysics Data System (ADS)

    Vajo, John; Pinkerton, Fred; Stetson, Ned

    2009-05-01

    Future energy technologies that use hydrogen as an energy carrier offer the tantalizing prospect of operating essentially free of pollutant and greenhouse gas emissions while utilizing hydrogen produced from a diverse range of renewable sources. To realize these technologies, such as hydrogen proton exchange membrane (PEM) fuel cells, improved approaches are needed for the high-capacity storage of hydrogen at temperatures ranging from near ambient to about 100 °C and at pressures below about 100 bar. These conditions favor storage based on the interaction of hydrogen with solid materials, rather than storage based on compressed or liquid hydrogen, which requires high pressures (700 bar) or low temperatures (20 K), respectively. Significant advances have recently been made, both in materials that store hydrogen as H2 molecules adsorbed on suitable supports and in materials that bind hydrogen chemically in the form of atoms, protons (cations) or hydride anions. Advances in molecular storage have come largely from a detailed understanding of the structures and bonding processes in traditional adsorbents and the development of new high-surface-area adsorbent materials with structures tailored on the molecular scale. Much of the emphasis has been on further increasing the number of adsorption sites to improve storage capacity. The low adsorption energies of current materials present another challenge because the weakly bound H2 can achieve technologically significant capacities only at cryogenic temperatures (50-80 K). Ongoing efforts to improve the thermodynamics of adsorption are primarily focused on composition and structure modifications. For chemically bound hydrogen, advances have come from investigation into light-element binary and complex hydrides, which inherently have high hydrogen capacities. The polar covalent bonding that characterizes these hydrides leads to very slow kinetics for hydrogen exchange, so here the emphasis is on improving kinetics through

  17. Autothermal hydrogen storage and delivery systems

    SciTech Connect

    Pez, Guido Peter; Cooper, Alan Charles; Scott, Aaron Raymond

    2011-08-23

    Processes are provided for the storage and release of hydrogen by means of dehydrogenation of hydrogen carrier compositions where at least part of the heat of dehydrogenation is provided by a hydrogen-reversible selective oxidation of the carrier. Autothermal generation of hydrogen is achieved wherein sufficient heat is provided to sustain the at least partial endothermic dehydrogenation of the carrier at reaction temperature. The at least partially dehydrogenated and at least partially selectively oxidized liquid carrier is regenerated in a catalytic hydrogenation process where apart from an incidental employment of process heat, gaseous hydrogen is the primary source of reversibly contained hydrogen and the necessary reaction energy.

  18. SSH2S: Hydrogen storage in complex hydrides for an auxiliary power unit based on high temperature proton exchange membrane fuel cells

    NASA Astrophysics Data System (ADS)

    Baricco, Marcello; Bang, Mads; Fichtner, Maximilian; Hauback, Bjorn; Linder, Marc; Luetto, Carlo; Moretto, Pietro; Sgroi, Mauro

    2017-02-01

    The main objective of the SSH2S (Fuel Cell Coupled Solid State Hydrogen Storage Tank) project was to develop a solid state hydrogen storage tank based on complex hydrides and to fully integrate it with a High Temperature Proton Exchange Membrane (HT-PEM) fuel cell stack. A mixed lithium amide/magnesium hydride system was used as the main storage material for the tank, due to its high gravimetric storage capacity and relatively low hydrogen desorption temperature. The mixed lithium amide/magnesium hydride system was coupled with a standard intermetallic compound to take advantage of its capability to release hydrogen at ambient temperature and to ensure a fast start-up of the system. The hydrogen storage tank was designed to feed a 1 kW HT-PEM stack for 2 h to be used for an Auxiliary Power Unit (APU). A full thermal integration was possible thanks to the high operation temperature of the fuel cell and to the relative low temperature (170 °C) for hydrogen release from the mixed lithium amide/magnesium hydride system.

  19. Metal assisted carbon cold storage of hydrogen

    SciTech Connect

    Schwarz, J.A.

    1988-01-05

    This patent describes a method of storing hydrogen by sorption on a composite formed of carbon and a transition metal, comprising the steps of contacting gaseous hydrogen with a storage medium formed of high surface area activated carbon combined with an active transition metal in elemental form capable of dissociating the hydrogen, physisorbing the hydrogen on the storage medium, and storing the sorbed hydrogen by maintaining the pressure at or above one bar and maintaining the temperature of the medium in a cold temperature range below 293 K.

  20. Hydrogen storage in metal-organic frameworks.

    PubMed

    Hu, Yun Hang; Zhang, Lei

    2010-05-25

    Metal-organic frameworks (MOFs) are highly attractive materials because of their ultra-high surface areas, simple preparation approaches, designable structures, and potential applications. In the past several years, MOFs have attracted worldwide attention in the area of hydrogen energy, particularly for hydrogen storage. In this review, the recent progress of hydrogen storage in MOFs is presented. The relationships between hydrogen capacities and structures of MOFs are evaluated, with emphasis on the roles of surface area and pore size. The interaction mechanism between H(2) and MOFs is discussed. The challenges to obtain a high hydrogen capacity at ambient temperature are explored.

  1. Quantitative phase analysis from powder diffraction using de Rietveld method in hydrogen storage alloys based on TiCr

    NASA Astrophysics Data System (ADS)

    Martinez, A.; Bellon, D.; Reina, L.

    2016-08-01

    Hydrogen storage is one of the important steps in the implementation of the hydrogen economy; metal hydrides are a promising way to achieve this goal. We present in this work the use of Rietveld analysis to characterize structurally TiCr-based alloys that are able to store hydrogen. TiCruV09, TiCrL1V0.45Nb0.45, TiCr1.1V0.2 Nb0.8, TiCr1.1Nb0.9 alloys were synthesized in an arc furnace under argon atmosphere. The analysis of phases was developed by X-Ray Diffraction (XRD) for further refinement of both the two lattice parameters and the percentage of the phases. Our results confirmed that a structure bcc, mostly combined with a small percentage of Laves phases, leads to obtain important properties in this area. Rietveld analysis was performed by the Fullprof program and this program allows us to obtain the different structural parameters.

  2. Efficient hydrogen storage and production using a catalyst with an imidazoline-based, proton-responsive ligand

    DOE PAGES

    Wang, Lin; Onishi, Naoya; Murata, Kazuhisa; ...

    2016-12-28

    A series of new imidazoline-based iridium complexes has been developed for hydrogenation of CO2 and dehydrogenation of formic acid. One of the proton-responsive complexes bearing two –OH groups at ortho and para positions on a coordinating pyridine ring (3 b) can catalyze efficiently the chemical fixation of CO2 and release H2 under mild conditions in aqueous media without using organic additives/solvents. Notably, hydrogenation of CO2 can be efficiently carried out under CO2 and H2 at atmospheric pressure in basic water by 3 b, achieving a turnover frequency of 106 h–1 and a turnover number of 7280 at 25 °C, whichmore » are higher than ever reported. Furthermore, highly efficient CO-free hydrogen production from formic acid in aqueous solution employing the same catalyst under mild conditions has been achieved, thus providing a promising potential H2-storage system in water.« less

  3. Efficient hydrogen storage and production using a catalyst with an imidazoline-based, proton-responsive ligand

    SciTech Connect

    Wang, Lin; Onishi, Naoya; Murata, Kazuhisa; Hirose, Takuji; Muckerman, James T.; Fujita, Etsuko; Himeda, Yuichiro

    2016-12-28

    A series of new imidazoline-based iridium complexes has been developed for hydrogenation of CO2 and dehydrogenation of formic acid. One of the proton-responsive complexes bearing two –OH groups at ortho and para positions on a coordinating pyridine ring (3 b) can catalyze efficiently the chemical fixation of CO2 and release H2 under mild conditions in aqueous media without using organic additives/solvents. Notably, hydrogenation of CO2 can be efficiently carried out under CO2 and H2 at atmospheric pressure in basic water by 3 b, achieving a turnover frequency of 106 h–1 and a turnover number of 7280 at 25 °C, which are higher than ever reported. Furthermore, highly efficient CO-free hydrogen production from formic acid in aqueous solution employing the same catalyst under mild conditions has been achieved, thus providing a promising potential H2-storage system in water.

  4. Efficient Hydrogen Storage and Production Using a Catalyst with an Imidazoline-Based, Proton-Responsive Ligand.

    PubMed

    Wang, Lin; Onishi, Naoya; Murata, Kazuhisa; Hirose, Takuji; Muckerman, James T; Fujita, Etsuko; Himeda, Yuichiro

    2017-03-22

    A series of new imidazoline-based iridium complexes has been developed for hydrogenation of CO2 and dehydrogenation of formic acid. One of the proton-responsive complexes bearing two -OH groups at ortho and para positions on a coordinating pyridine ring (3 b) can catalyze efficiently the chemical fixation of CO2 and release H2 under mild conditions in aqueous media without using organic additives/solvents. Notably, hydrogenation of CO2 can be efficiently carried out under CO2 and H2 at atmospheric pressure in basic water by 3 b, achieving a turnover frequency of 106 h(-1) and a turnover number of 7280 at 25 °C, which are higher than ever reported. Moreover, highly efficient CO-free hydrogen production from formic acid in aqueous solution employing the same catalyst under mild conditions has been achieved, thus providing a promising potential H2 -storage system in water. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Polymer-induced surface modifications of Pd-based thin films leading to improved kinetics in hydrogen sensing and energy storage applications.

    PubMed

    Ngene, Peter; Westerwaal, Ruud J; Sachdeva, Sumit; Haije, Wim; de Smet, Louis C P M; Dam, Bernard

    2014-11-03

    The catalytic properties of Pd alloy thin films are enhanced by a thin sputtered PTFE coating, resulting in profound improvements in hydrogen adsorption and desorption in Pd-based and Pd-catalyzed hydrogen sensors and hydrogen storage materials. The remarkably enhanced catalytic performance is attributed to chemical modifications of the catalyst surface by the sputtered PTFE leading to a possible change in the binding strength of the intermediate species involved in the hydrogen sorption process. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Polyaniline as a material for hydrogen storage applications.

    PubMed

    Attia, Nour F; Geckeler, Kurt E

    2013-07-12

    The main challenge of commercialization of the hydrogen economy is the lack of convenient and safe hydrogen storage materials, which can adsorb and release a significant amount of hydrogen at ambient conditions. Finding and designing suitable cost-effective materials are vital requirements to overcome the drawbacks of investigated materials. Because of its outstanding electronic, thermal, and chemical properties, the electrically conducting polyaniline (PANI) has a high potential in hydrogen storage applications. In this review, the progress in the use of different structures of conducting PANI, its nanocomposites as well as activated porous materials based on PANI as hydrogen storage materials is presented and discussed. The effect of the unique electronic properties based on the π-electron system in the backbone of these materials in view of the hydrogen uptake and the relevant mechanisms are highlighted. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Storage, transmission and distribution of hydrogen

    NASA Technical Reports Server (NTRS)

    Kelley, J. H.; Hagler, R., Jr.

    1979-01-01

    Current practices and future requirements for the storage, transmission and distribution of hydrogen are reviewed in order to identify inadequacies to be corrected before hydrogen can achieve its full potential as a substitute for fossil fuels. Consideration is given to the storage of hydrogen in underground solution-mined salt caverns, portable high-pressure containers and dewars, pressure vessels and aquifers and as metal hydrides, hydrogen transmission in evacuated double-walled insulated containers and by pipeline, and distribution by truck and internal distribution networks. Areas for the improvement of these techniques are indicated, and these technological deficiencies, including materials development, low-cost storage and transmission methods, low-cost, long-life metal hydrides and novel methods for hydrogen storage, are presented as challenges for research and development.

  8. Storage, transmission and distribution of hydrogen

    NASA Technical Reports Server (NTRS)

    Kelley, J. H.; Hagler, R., Jr.

    1979-01-01

    Current practices and future requirements for the storage, transmission and distribution of hydrogen are reviewed in order to identify inadequacies to be corrected before hydrogen can achieve its full potential as a substitute for fossil fuels. Consideration is given to the storage of hydrogen in underground solution-mined salt caverns, portable high-pressure containers and dewars, pressure vessels and aquifers and as metal hydrides, hydrogen transmission in evacuated double-walled insulated containers and by pipeline, and distribution by truck and internal distribution networks. Areas for the improvement of these techniques are indicated, and these technological deficiencies, including materials development, low-cost storage and transmission methods, low-cost, long-life metal hydrides and novel methods for hydrogen storage, are presented as challenges for research and development.

  9. Theoretical Studies of Hydrogen Storage Alloys.

    SciTech Connect

    Jonsson, Hannes

    2012-03-22

    Theoretical calculations were carried out to search for lightweight alloys that can be used to reversibly store hydrogen in mobile applications, such as automobiles. Our primary focus was on magnesium based alloys. While MgH{sub 2} is in many respects a promising hydrogen storage material, there are two serious problems which need to be solved in order to make it useful: (i) the binding energy of the hydrogen atoms in the hydride is too large, causing the release temperature to be too high, and (ii) the diffusion of hydrogen through the hydride is so slow that loading of hydrogen into the metal takes much too long. In the first year of the project, we found that the addition of ca. 15% of aluminum decreases the binding energy to the hydrogen to the target value of 0.25 eV which corresponds to release of 1 bar hydrogen gas at 100 degrees C. Also, the addition of ca. 15% of transition metal atoms, such as Ti or V, reduces the formation energy of interstitial H-atoms making the diffusion of H-atoms through the hydride more than ten orders of magnitude faster at room temperature. In the second year of the project, several calculations of alloys of magnesium with various other transition metals were carried out and systematic trends in stability, hydrogen binding energy and diffusivity established. Some calculations of ternary alloys and their hydrides were also carried out, for example of Mg{sub 6}AlTiH{sub 16}. It was found that the binding energy reduction due to the addition of aluminum and increased diffusivity due to the addition of a transition metal are both effective at the same time. This material would in principle work well for hydrogen storage but it is, unfortunately, unstable with respect to phase separation. A search was made for a ternary alloy of this type where both the alloy and the corresponding hydride are stable. Promising results were obtained by including Zn in the alloy.

  10. Efficient storage system for breath hydrogen.

    PubMed

    Murray, R D; Kerzner, B; MacLean, W C; McClung, H J; Gilbert, M

    1985-10-01

    Recommended materials for breath hydrogen collection (plastic syringes with twist lock closure) are only adequate for relatively brief periods because of gradual hydrogen loss and considerable variability between duplicate samples. To document the most favorable storage conditions for breath hydrogen, we compared hydrogen retention in plastic syringes using a conventional twist-in-lock closure versus a simple, inexpensive syringe closure, a Critocap. Hydrogen retention was studied at 25, 5, and -20 degrees C in two different syringe brands over 72 h of storage. An analysis of variance confirms the superiority of Critocaps over twist-in-lock closures (p less than 0.001). Reliability was maximal when samples were placed in environments less than 5 degrees C. When storage time was extended to 7 days, mean hydrogen retention was 86 +/- 6% (means +/- SD).

  11. Hydrogen storage and delivery system development

    SciTech Connect

    Handrock, J.L.; Wally, K.; Raber, T.N.

    1995-09-01

    Hydrogen storage and delivery is an important element in effective hydrogen utilization for energy applications and is an important part of the FY1994-1998 Hydrogen Program Implementation Plan. The purpose of this project is to develop a platform for the engineering evaluation of hydrogen storage and delivery systems with an added focus on lightweight hydride utilization. Hybrid vehicles represent the primary application area of interest, with secondary interests including such items as existing vehicles and stationary uses. The near term goal is the demonstration of an internal combustion engine/storage/delivery subsystem. The long term goal is optimization of storage technologies for both vehicular and industrial stationary uses. In this project an integrated approach is being used to couple system operating characteristics to hardware development. A model has been developed which integrates engine and storage material characteristics into the design of hydride storage and delivery systems. By specifying engine operating parameters, as well as a variety of storage/delivery design features, hydride bed sizing calculations are completed. The model allows engineering trade-off studies to be completed on various hydride material/delivery system configurations. A more generalized model is also being developed to allow the performance characteristics of various hydrogen storage and delivery systems to be compared (liquid, activated carbon, etc.). Many of the features of the hydride storage model are applicable to the development of this more generalized model.

  12. Optimization and comprehensive characterization of metal hydride based hydrogen storage systems using in-situ Neutron Radiography

    NASA Astrophysics Data System (ADS)

    Börries, S.; Metz, O.; Pranzas, P. K.; Bellosta von Colbe, J. M.; Bücherl, T.; Dornheim, M.; Klassen, T.; Schreyer, A.

    2016-10-01

    For the storage of hydrogen, complex metal hydrides are considered as highly promising with respect to capacity, reversibility and safety. The optimization of corresponding storage tanks demands a precise and time-resolved investigation of the hydrogen distribution in scaled-up metal hydride beds. In this study it is shown that in situ fission Neutron Radiography provides unique insights into the spatial distribution of hydrogen even for scaled-up compacts and therewith enables a direct study of hydrogen storage tanks. A technique is introduced for the precise quantification of both time-resolved data and a priori material distribution, allowing inter alia for an optimization of compacts manufacturing process. For the first time, several macroscopic fields are combined which elucidates the great potential of Neutron Imaging for investigations of metal hydrides by going further than solely 'imaging' the system: A combination of in-situ Neutron Radiography, IR-Thermography and thermodynamic quantities can reveal the interdependency of different driving forces for a scaled-up sodium alanate pellet by means of a multi-correlation analysis. A decisive and time-resolved, complex influence of material packing density is derived. The results of this study enable a variety of new investigation possibilities that provide essential information on the optimization of future hydrogen storage tanks.

  13. Hydrogen storage using carbon adsorbents: past, present and future

    NASA Astrophysics Data System (ADS)

    Dillon, A. C.; Heben, M. J.

    2001-03-01

    Interest in hydrogen as a fuel has grown dramatically since 1990, and many advances in hydrogen production and utilization technologies have been made. However, hydrogen storage technologies must be significantly advanced if a hydrogen based energy system, particularly in the transportation sector, is to be established. Hydrogen can be made available on-board vehicles in containers of compressed or liquefied H2, in metal hydrides, via chemical storage or by gas-on-solid adsorption. Although each method possesses desirable characteristics, no approach satisfies all of the efficiency, size, weight, cost and safety requirements for transportation or utility use. Gas-on-solid adsorption is an inherently safe and potentially high energy density hydrogen storage method that could be extremely energy efficient. Consequently, the hydrogen storage properties of high surface area ``activated'' carbons have been extensively studied. However, activated carbons are ineffective in storing hydrogen because only a small fraction of the pores in the typically wide pore-size distribution are small enough to interact strongly with hydrogen molecules at room temperatures and moderate pressures. Recently, many new carbon nanostructured absorbents have been produced including graphite nanofibers and carbon multi-wall and single-wall nanotubes. The following review provides a brief history of the hydrogen adsorption studies on activated carbons and comments on the recent experimental and theoretical investigations of the hydrogen adsorption properties of the new nanostructured carbon materials.

  14. Hydrogen Storage Technologies for Future Energy Systems.

    PubMed

    Preuster, Patrick; Alekseev, Alexander; Wasserscheid, Peter

    2017-06-07

    Future energy systems will be determined by the increasing relevance of solar and wind energy. Crude oil and gas prices are expected to increase in the long run, and penalties for CO2 emissions will become a relevant economic factor. Solar- and wind-powered electricity will become significantly cheaper, such that hydrogen produced from electrolysis will be competitively priced against hydrogen manufactured from natural gas. However, to handle the unsteadiness of system input from fluctuating energy sources, energy storage technologies that cover the full scale of power (in megawatts) and energy storage amounts (in megawatt hours) are required. Hydrogen, in particular, is a promising secondary energy vector for storing, transporting, and distributing large and very large amounts of energy at the gigawatt-hour and terawatt-hour scales. However, we also discuss energy storage at the 120-200-kWh scale, for example, for onboard hydrogen storage in fuel cell vehicles using compressed hydrogen storage. This article focuses on the characteristics and development potential of hydrogen storage technologies in light of such a changing energy system and its related challenges. Technological factors that influence the dynamics, flexibility, and operating costs of unsteady operation are therefore highlighted in particular. Moreover, the potential for using renewable hydrogen in the mobility sector, industrial production, and the heat market is discussed, as this potential may determine to a significant extent the future economic value of hydrogen storage technology as it applies to other industries. This evaluation elucidates known and well-established options for hydrogen storage and may guide the development and direction of newer, less developed technologies.

  15. Hydrogen storage and delivery system development: Fabrication

    SciTech Connect

    Handrock, J.L.; Malinowski, M.E.; Wally, K.

    1996-10-01

    Hydrogen storage and delivery is an important element in effective hydrogen utilization for energy applications and is an important part of the FY1994-1998 Hydrogen Program Implementation Plan. This project is part of the Field Work Proposal entitled Hydrogen Utilization in Internal Combustion Engines (ICE). The goal of the Hydrogen Storage and Delivery System Development Project is to expand the state-of-the-art of hydrogen storage and delivery system design and development. At the foundation of this activity is the development of both analytical and experimental evaluation platforms. These tools provide the basis for an integrated approach for coupling hydrogen storage and delivery technology to the operating characteristics of potential hydrogen energy use applications. Analytical models have been developed for internal combustion engine (ICE) hybrid and fuel cell driven vehicles. The dependence of hydride storage system weight and energy use efficiency on engine brake efficiency and exhaust temperature for ICE hybrid vehicle applications is examined. Results show that while storage system weight decreases with increasing engine brake efficiency energy use efficiency remains relatively unchanged. The development, capability, and use of a newly developed fuel cell vehicle hydride storage system model will also be discussed. As an example of model use power distribution and control for a simulated driving cycle is presented. An experimental test facility, the Hydride Bed Testing Laboratory (HBTL) has been designed and fabricated. The development of this facility and its use in storage system development will be reviewed. These two capabilities (analytical and experimental) form the basis of an integrated approach to storage system design and development. The initial focus of these activities has been on hydride utilization for vehicular applications.

  16. Pad B Liquid Hydrogen Storage Tank

    NASA Technical Reports Server (NTRS)

    Hall, Felicia

    2007-01-01

    Kennedy Space Center is home to two liquid hydrogen storage tanks, one at each launch pad of Launch Complex 39. The liquid hydrogen storage tank at Launch Pad B has a significantly higher boil off rate that the liquid hydrogen storage tank at Launch Pad A. This research looks at various calculations concerning the at Launch Pad B in an attempt to develop a solution to the excess boil off rate. We will look at Perlite levels inside the tank, Boil off rates, conductive heat transfer, and radiant heat transfer through the tank. As a conclusion to the research, we will model the effects of placing an external insulation to the tank in order to reduce the boil off rate and increase the economic efficiency of the liquid hydrogen storage tanks.

  17. Large-scale screening of metal hydrides for hydrogen storage from first-principles calculations based on equilibrium reaction thermodynamics.

    PubMed

    Kim, Ki Chul; Kulkarni, Anant D; Johnson, J Karl; Sholl, David S

    2011-04-21

    Systematic thermodynamics calculations based on density functional theory-calculated energies for crystalline solids have been a useful complement to experimental studies of hydrogen storage in metal hydrides. We report the most comprehensive set of thermodynamics calculations for mixtures of light metal hydrides to date by performing grand canonical linear programming screening on a database of 359 compounds, including 147 compounds not previously examined by us. This database is used to categorize the reaction thermodynamics of all mixtures containing any four non-H elements among Al, B, C, Ca, K, Li, Mg, N, Na, Sc, Si, Ti, and V. Reactions are categorized according to the amount of H(2) that is released and the reaction's enthalpy. This approach identifies 74 distinct single step reactions having that a storage capacity >6 wt.% and zero temperature heats of reaction 15 ≤ΔU(0)≤ 75 kJ mol(-1) H(2). Many of these reactions, however, are likely to be problematic experimentally because of the role of refractory compounds, B(12)H(12)-containing compounds, or carbon. The single most promising reaction identified in this way involves LiNH(2)/LiH/KBH(4), storing 7.48 wt.% H(2) and having ΔU(0) = 43.6 kJ mol(-1) H(2). We also examined the complete range of reaction mixtures to identify multi-step reactions with useful properties; this yielded 23 multi-step reactions of potential interest.

  18. Porous polymeric materials for hydrogen storage

    DOEpatents

    Yu, Luping; Liu, Di-Jia; Yuan, Shengwen; Yang, Junbing

    2013-04-02

    A porous polymer, poly-9,9'-spirobifluorene and its derivatives for storage of H.sub.2 are prepared through a chemical synthesis method. The porous polymers have high specific surface area and narrow pore size distribution. Hydrogen uptake measurements conducted for these polymers determined a higher hydrogen storage capacity at the ambient temperature over that of the benchmark materials. The method of preparing such polymers, includes oxidatively activating solids by CO.sub.2/steam oxidation and supercritical water treatment.

  19. Hydrogen transport and storage in engineered microspheres

    SciTech Connect

    Rambach, G.; Hendricks, C.

    1996-10-01

    This project is a collaboration between Lawrence Livermore National Laboratory (LLNL) and W.J. Schafer Associates (WJSA). The authors plan to experimentally verify the performance characteristics of engineered glass microspheres that are relevant to the storage and transport of hydrogen for energy applications. They will identify the specific advantages of hydrogen transport by microspheres, analyze the infrastructure implications and requirements, and experimentally measure their performance characteristics in realistic, bulk storage situations.

  20. Liquid-phase chemical hydrogen storage: catalytic hydrogen generation under ambient conditions.

    PubMed

    Jiang, Hai-Long; Singh, Sanjay Kumar; Yan, Jun-Min; Zhang, Xin-Bo; Xu, Qiang

    2010-05-25

    There is a demand for a sufficient and sustainable energy supply. Hence, the search for applicable hydrogen storage materials is extremely important owing to the diversified merits of hydrogen energy. Lithium and sodium borohydride, ammonia borane, hydrazine, and formic acid have been extensively investigated as promising hydrogen storage materials based on their relatively high hydrogen content. Significant advances, such as hydrogen generation temperatures and reaction kinetics, have been made in the catalytic hydrolysis of aqueous lithium and sodium borohydride and ammonia borane as well as in the catalytic decomposition of hydrous hydrazine and formic acid. In this Minireview we briefly survey the research progresses in catalytic hydrogen generation from these liquid-phase chemical hydrogen storage materials.

  1. Carbon nanotube materials for hydrogen storage

    SciTech Connect

    Dillon, A.C.; Jones, K.M.; Heben, M.J.

    1996-10-01

    Hydrogen burns pollution-free and may be produced from renewable energy resources. It is therefore an ideal candidate to replace fossil fuels as an energy carrier. However, the lack of a convenient and cost-effective hydrogen storage system greatly impedes the wide-scale use of hydrogen in both domestic and international markets. Although several hydrogen storage options exist, no approach satisfies all of the efficiency, size, weight, cost and safety requirements for transportation or utility use. A material consisting exclusively of micropores with molecular dimensions could simultaneously meet all of the requirements for transportation use if the interaction energy for hydrogen was sufficiently strong to cause hydrogen adsorption at ambient temperatures. Small diameter ({approx}1 mm) carbon single-wall nanotubes (SWNTs) are elongated micropores of molecular dimensions, and materials composed predominantly of SWNTs may prove to be the ideal adsorbent for ambient temperature storage of hydrogen. Last year the authors reported that hydrogen could be adsorbed on arc-generated soots containing 12{Angstrom} diameter nanotubes at temperatures in excess of 285K. In this past year they have learned that such adsorption does not occur on activated carbon materials, and that the cobalt nanoparticles present in their arc-generated soots are not responsible for the hydrogen which is stable at 285 K. These results indicate that enhanced adsorption forces within the internal cavities of the SWNTs are active in stabilizing hydrogen at elevated temperatures. This enhanced stability could lead to effective hydrogen storage under ambient temperature conditions. In the past year the authors have also demonstrated that single-wall carbon nanotubes in arc-generated soots may be selectively opened by oxidation in H{sub 2}O resulting in improved hydrogen adsorption, and they have estimated experimentally that the amount of hydrogen stored is {approximately}10% of the nanotube weight.

  2. Hydrogen storage and delivery system development: Analysis

    SciTech Connect

    Handrock, J.L.

    1996-10-01

    Hydrogen storage and delivery is an important element in effective hydrogen utilization for energy applications and is an important part of the FY1994-1998 Hydrogen Program Implementation Plan. This project is part of the Field Work Proposal entitled Hydrogen Utilization in Internal Combustion Engines (ICE). The goal of the Hydrogen Storage and Delivery System Development Project is to expand the state-of-the-art of hydrogen storage and delivery system design and development. At the foundation of this activity is the development of both analytical and experimental evaluation platforms. These tools provide the basis for an integrated approach for coupling hydrogen storage and delivery technology to the operating characteristics of potential hydrogen energy use applications. Results of the analytical model development portion of this project will be discussed. Analytical models have been developed for internal combustion engine (ICE) hybrid and fuel cell driven vehicles. The dependence of hydride storage system weight and energy use efficiency on engine brake efficiency and exhaust temperature for ICE hybrid vehicle applications is examined. Results show that while storage system weight decreases with increasing engine brake efficiency energy use efficiency remains relatively unchanged. The development, capability, and use of a recently developed fuel cell vehicle storage system model will also be discussed. As an example of model use, power distribution and control for a simulated driving cycle is presented. Model calibration results of fuel cell fluid inlet and exit temperatures at various fuel cell idle speeds, assumed fuel cell heat capacities, and ambient temperatures are presented. The model predicts general increases in temperature with fuel cell power and differences between inlet and exit temperatures, but under predicts absolute temperature values, especially at higher power levels.

  3. Inherent safety key performance indicators for hydrogen storage systems.

    PubMed

    Landucci, Gabriele; Tugnoli, Alessandro; Cozzani, Valerio

    2008-11-30

    The expected inherent safety performance of hydrogen storage technologies was investigated. Reference schemes were defined for alternative processes proposed for hydrogen storage, and several storage potentialities were considered. The expected safety performance of alternative process technologies was explored estimating key performance indicators based on consequence assessment and credit factors of possible loss of containment events. The results indicated that the potential hazard is always lower for the innovative technologies proposed for hydrogen storage, as metal or complex hydrides. This derived mainly from the application of the inherent safety principles of "substitution" and "moderation", since in these processes hydrogen is stored as a less hazardous hydride. However, the results also evidenced that in the perspective of an industrial implementation of these technologies, the reliability of the auxiliary equipment will be a critical issue to be addressed.

  4. Microscale Enhancement of Heat and Mass Transfer for Hydrogen Energy Storage

    SciTech Connect

    Drost, Kevin; Jovanovic, Goran; Paul, Brian

    2015-09-30

    The document summarized the technical progress associated with OSU’s involvement in the Hydrogen Storage Engineering Center of Excellence. OSU focused on the development of microscale enhancement technologies for improving heat and mass transfer in automotive hydrogen storage systems. OSU’s key contributions included the development of an extremely compact microchannel combustion system for discharging hydrogen storage systems and a thermal management system for adsorption based hydrogen storage using microchannel cooling (the Modular Adsorption Tank Insert or MATI).

  5. Influence of nickel nanoparticles on hydrogen storage behaviors of MWCNTs

    NASA Astrophysics Data System (ADS)

    Han, Ye-Ji; Park, Soo-Jin

    2017-09-01

    In this study, multiwalled carbon nanotube (CNT)-nickel hybrid materials were prepared from CNTs by the impregnation of nickel at various CNT/nickel mass ratios. The presence of nickel nanoparticles on CNTs influences the spillover effect on hydrogen storage capacity. A thermal reduction method was employed to increase the contacts between the nickel metal particles and the carbon support, thus facilitating hydrogen spillover. The as-obtained nickel-decorated CNTs exhibited a high hydrogen storage capacity of 0.87 wt.% at 298 K and 100 bar, resulting in an enhancement factor of 2.5 relative to the untreated CNTs. These experimental results demonstrate that the presence of nickel creates hydrogen-favorable sites that can lead to improved hydrogen storage capacities based on the spillover effect.

  6. Supported iron based redox systems for hydrogen production and storage from ethanol

    NASA Astrophysics Data System (ADS)

    Rosmaninho, M. G.; Souza, L. R.; Gomes, G. M.; Zica, R. F.; Nascimento, J. S.; Pereira, M. C.; Fabris, J. D.; Ardison, J. D.; Moura, F. C. C.; Lago, R. M.; Araujo, M. H.

    2010-01-01

    Hydrogen production using ethanol and Fe2O3/support in a redox cycle was investigated. The composites were prepared by impregnation of Al2O3 and SiO2 with Fe(NO3)3, with different proportions of iron, i.e. 10, 30 and 50 wt.%, calcinated at 450°C and characterized by Mössbauer spectroscopy, XRD, SEM, BET and TG. The redox cycle to produce and/or store hydrogen is a two step process (1) initially the ethanol is used to reduce the iron oxide to Fe°; (2) and when H2 is needed, Fe° reacts with H2O to produce CO-free hydrogen, and the iron oxide is reduced again to Fe° making this system cyclic. After the reactions it was interesting to observe that ethanol can directly reduce the iron oxide to produce metallic iron, with carbon deposition and iron-carbon as side product. Preliminary results indicate that it is possible to perform multiple redox cycles with the supported iron oxide without deactivation.

  7. LIGHT-WEIGHT NANOCRYSTALLINE HYDROGEN STORAGE MATERIALS

    SciTech Connect

    S. G. Sankar; B. Zande; R.T. Obermyer; S. Simizu

    2005-11-21

    During Phase I of this SBIR Program, Advanced Materials Corporation has addressed two key issues concerning hydrogen storage: 1. We have conducted preliminary studies on the effect of certain catalysts in modifying the hydrogen absorption characteristics of nanocrystalline magnesium. 2. We have also conducted proof-of-concept design and construction of a prototype instrument that would rapidly screen materials for hydrogen storage employing chemical combinatorial technique in combination with a Pressure-Composition Isotherm Measurement (PCI) instrument. 3. Preliminary results obtained in this study approach are described in this report.

  8. Electric utility applications of hydrogen energy storage systems

    SciTech Connect

    Swaminathan, S.; Sen, R.K.

    1997-10-15

    This report examines the capital cost associated with various energy storage systems that have been installed for electric utility application. The storage systems considered in this study are Battery Energy Storage (BES), Superconducting Magnetic Energy Storage (SMES) and Flywheel Energy Storage (FES). The report also projects the cost reductions that may be anticipated as these technologies come down the learning curve. This data will serve as a base-line for comparing the cost-effectiveness of hydrogen energy storage (HES) systems in the electric utility sector. Since pumped hydro or compressed air energy storage (CAES) is not particularly suitable for distributed storage, they are not considered in this report. There are no comparable HES systems in existence in the electric utility sector. However, there are numerous studies that have assessed the current and projected cost of hydrogen energy storage system. This report uses such data to compare the cost of HES systems with that of other storage systems in order to draw some conclusions as to the applications and the cost-effectiveness of hydrogen as a electricity storage alternative.

  9. A computational study on novel carbon-based lithium materials for hydrogen storage and the role of carbon in destabilizing complex metal hydrides

    NASA Astrophysics Data System (ADS)

    Ghouri, Mohammed Minhaj

    One of the major impediments in the way of the realization of hydrogen economy is the storage of hydrogen gas. This involves both the storage for stationary applications as well as that of storage onboard vehicles for transportation applications. For obvious reasons, the system targets for the automotive applications are more stringent. There are many approaches which are still being researched for the storage of hydrogen for vehicular applications. Among them are the high pressure storage of hydrogen gas and the storing of liquid hydrogen in super insulated cryogenic cylinders. While both of them have been demonstrated practically, the high stakes of their respective shortcomings is hindering the wide spread application of these methods. Thus different solid state storage materials are being looked upon as promising solutions. Metal hydrides are a class of solid state hydrogen storage materials which are formed by the reaction of metals or their alloys with hydrogen. These materials have very good gravimetric storage densities, but are very stable thermodynamically to desorp hydrogen at room temperatures. Research is going on to improve the thermodynamics and the reaction kinetics of different metal hydrides. This dissertation tries to address the problem of high thermodynamic stability of the existing metal hydrides in two ways. First, a novel carbon based lithium material is proposed as a viable storage option based on its promising thermodynamic heat of formation. Pure beryllium (Be) clusters and the carbon-beryllium (C-Be) clusters are studied in detail using the Density Functional Theory (DFT) computational methods. Their interactions with hydrogen molecule are further studied. The results of these calculations indicate that hydrogen is more strongly physisorbed to the beryllium atom in the C-Be cluster, rather than to a carbon atom. After these initial studies, we calculated the geometries and the energies of more than 100 different carbon based lithium

  10. Improved metal hydride technology for the storage of hydrogen

    SciTech Connect

    Sapru, K.; Ming, L.; Ramachandran, S.

    1995-09-01

    Low cost, high density storage of hydrogen will remove the most serious barrier to large-scale utilization of hydrogen as a non-polluting, zero-emission fuel. An important challenge for the practical use of Mg-based, high capacity hydrogen storage alloys has been the development of a low-cost, bulk production technique. Two difficulties in preparation of Mg-based alloys are the immiscibility of Mg with many transition metals and the relatively high volatility of Mg compared to many transition metals. These factors preclude the use of conventional induction melting techniques for the Mg-based alloy preparation. A mechanical alloying technique, in which Mg immiscibility and volatility do not present a problem, was developed and shows great promise for production of Mg-based alloys. A number of Mg-based alloys were prepared via modified induction melting and mechanical alloying methods. The alloys were tested for gas phase hydrogen storage properties, composition, structure and morphology. The mechanically alloyed samples are multi-component, multi-phase, highly disordered materials in their as-prepared state. These unoptimized alloys have shown reversible H-storage capacity of more than 5 wt.% hydrogen. After 2000 absorption/desorption cycles, the alloys show no decline in storage capacity or desorption kinetics. The alloys have also demonstrated resistance to CH{sub 4} and CO poisoning in preliminary testing. Upon annealing, with an increase in crystallinity, the H-storage capacity decreases, indicating the importance of disorder.

  11. U.S. Department of Energy Hydrogen Storage Cost Analysis

    SciTech Connect

    Law, Karen; Rosenfeld, Jeffrey; Han, Vickie; Chan, Michael; Chiang, Helena; Leonard, Jon

    2013-03-11

    The overall objective of this project is to conduct cost analyses and estimate costs for on- and off-board hydrogen storage technologies under development by the U.S. Department of Energy (DOE) on a consistent, independent basis. This can help guide DOE and stakeholders toward the most-promising research, development and commercialization pathways for hydrogen-fueled vehicles. A specific focus of the project is to estimate hydrogen storage system cost in high-volume production scenarios relative to the DOE target that was in place when this cost analysis was initiated. This report and its results reflect work conducted by TIAX between 2004 and 2012, including recent refinements and updates. The report provides a system-level evaluation of costs and performance for four broad categories of on-board hydrogen storage: (1) reversible on-board metal hydrides (e.g., magnesium hydride, sodium alanate); (2) regenerable off-board chemical hydrogen storage materials(e.g., hydrolysis of sodium borohydride, ammonia borane); (3) high surface area sorbents (e.g., carbon-based materials); and 4) advanced physical storage (e.g., 700-bar compressed, cryo-compressed and liquid hydrogen). Additionally, the off-board efficiency and processing costs of several hydrogen storage systems were evaluated and reported, including: (1) liquid carrier, (2) sodium borohydride, (3) ammonia borane, and (4) magnesium hydride. TIAX applied a bottom-up costing methodology customized to analyze and quantify the processes used in the manufacture of hydrogen storage systems. This methodology, used in conjunction with ® software and other tools, developed costs for all major tank components, balance-of-tank, tank assembly, and system assembly. Based on this methodology, the figure below shows the projected on-board high-volume factory costs of the various analyzed hydrogen storage systems, as designed. Reductions in the key cost drivers may bring hydrogen storage system costs closer to this DOE target

  12. Electrochemical performance and capacity degradation mechanism of single-phase La-Mg-Ni-based hydrogen storage alloys

    NASA Astrophysics Data System (ADS)

    Liu, Jingjing; Li, Yuan; Han, Da; Yang, Shuqin; Chen, Xiaocui; Zhang, Lu; Han, Shumin

    2015-12-01

    La-Mg-Ni-based hydrogen storage alloys are a promising candidate for the negative electrode materials of nickel metal hydride batteries. However, their fast capacity degradation hinders them from more extensive application. In this study, the electrochemical performance and capacity degradation mechanism of single-phase La2MgNi9, La3MgNi14 and La4MgNi19 alloys are studied from the perspective of their constituent subunits. It is found that the rate capability and cycling stability of the alloy electrodes increase with higher [LaNi5]/[LaMgNi4] subunit ratio, while the discharge capacity shows a reverse trend. Degradation study shows that the inter-molecular strains in the alloys are the main reason that leads to the fast capacity degradation of La-Mg-Ni-based alloys. The strains are caused by the difference in the expansion/contraction properties between [LaNi5] and [LaMgNi4] subunits during charge/discharge which is mainly observed in the H-dissolved solid solution instead of hydride. It is also found that the strains can be relieved by adjusting [LaNi5]/[LaMgNi4] subunit ratio of the alloys, thus achieving less pulverization and oxidation, and better cycling stability. We expect our findings can inspire new thoughts on improving the electrochemical performance of La-Mg-Ni-based alloys by tuning their superlattice structures.

  13. DEVELOPMENT OF DOPED NANOPOROUS CARBONS FOR HYDROGEN STORAGE

    SciTech Connect

    Lueking, Angela D.; Li, Qixiu; Badding, John V.; Fonseca, Dania; Gutierrez, Humerto; Sakti, Apurba; Adu, Kofi; Schimmel, Michael

    2010-03-31

    Hydrogen storage materials based on the hydrogen spillover mechanism onto metal-doped nanoporous carbons are studied, in an effort to develop materials that store appreciable hydrogen at ambient temperatures and moderate pressures. We demonstrate that oxidation of the carbon surface can significantly increase the hydrogen uptake of these materials, primarily at low pressure. Trace water present in the system plays a role in the development of active sites, and may further be used as a strategy to increase uptake. Increased surface density of oxygen groups led to a significant enhancement of hydrogen spillover at pressures less than 100 milibar. At 300K, the hydrogen uptake was up to 1.1 wt. % at 100 mbar and increased to 1.4 wt. % at 20 bar. However, only 0.4 wt% of this was desorbable via a pressure reduction at room temperature, and the high lowpressure hydrogen uptake was found only when trace water was present during pretreatment. Although far from DOE hydrogen storage targets, storage at ambient temperature has significant practical advantages oner cryogenic physical adsorbents. The role of trace water in surface modification has significant implications for reproducibility in the field. High-pressure in situ characterization of ideal carbon surfaces in hydrogen suggests re-hybridization is not likely under conditions of practical interest. Advanced characterization is used to probe carbon-hydrogen-metal interactions in a number of systems and new carbon materials have been developed.

  14. The USDOE Hydrogen Program: Status and Performance Gaps of On-board Hydrogen Storage Technologies

    NASA Astrophysics Data System (ADS)

    Ordaz, Grace; Gardiner, Monterey; Read, Carole; Stetson, Ned

    2009-03-01

    The USDOE Hydrogen Program's mission is to reduce oil use and carbon emissions in the US transportation sector and to enable clean, reliable energy for stationary and portable power generation. The requirements for vehicular hydrogen storage continue to be one of the most technically challenging barriers to the widespread commercialization of hydrogen fueled vehicles. The DOE applied hydrogen storage activity focuses primarily on the research and development of low-pressure, materials-based technologies to allow for a North American market driving range of more than 300 miles (500 km) while meeting packaging, cost, safety, and performance requirements to be competitive with current vehicles. This presentation summarizes the status, recent accomplishments and current performance gaps of hydrogen storage technologies primarily for transportation applications. Materials projects are focused in three main areas: metal hydrides, chemical hydrogen storage materials, and hydrogen sorbents. A new effort is the Hydrogen Storage Engineering Center of Excellence which will provide a coordinated approach to the engineering research and development of on-board storage and refueling systems. The presentation will especially highlight topics emphasized in the session theme.

  15. Mn in misch-metal based superlattice metal hydride alloy - Part 1 structural, hydrogen storage and electrochemical properties

    NASA Astrophysics Data System (ADS)

    Young, K.; Wong, D. F.; Wang, L.; Nei, J.; Ouchi, T.; Yasuoka, S.

    2015-03-01

    The structural, gaseous phase hydrogen storage, and electrochemical properties of a series of Mn-modified misch-metal based superlattice metal hydride alloys were investigated in part one of this two-part series of papers. X-ray diffraction analysis showed that these alloys are all multi-phased compositions with different abundances of AB2, AB3, A2B7, AB4, and AB5 phases. Substitution of Ni in the B-site by Mn promotes AB5 phase formation and decreases both gaseous phase and electrochemical capacities due to the reduction in the abundance of main hexagonal A2B7 phase. AC impedance and magnetic susceptibility measurement were employed to characterize the surface of Mn-free and Mn-modified alloys and show deterioration in surface catalytic ability as the Mn-content increases. Mn-modification adversely affected misch-metal based superlattice metal hydride alloy properties such as phase homogeneity, capacity, cycle stability, high-rate performance, and surface reaction.

  16. Enhanced hydrogen storage by using lithium decoration on phosphorene

    SciTech Connect

    Yu, Zhiyuan; Wan, Neng E-mail: lsy@seu.edu.cn; Lei, Shuangying E-mail: lsy@seu.edu.cn; Yu, Hong

    2016-07-14

    The hydrogen storage characteristics of Li decorated phosphorene were systematically investigated based on first-principle density functional theory. It is revealed that the adsorption of H{sub 2} on pristine phosphorene is relatively weak with an adsorption energy of 0.06 eV. While this value can be dramatically enhanced to ∼0.2 eV after the phosphorene was decorated by Li, and each Li atom can adsorb up to three H{sub 2} molecules. The detailed mechanism of the enhanced hydrogen storage was discussed based on our density functional theory calculations. Our studies give a conservative prediction of hydrogen storage capacity to be 4.4 wt. % through Li decoration on pristine phosphorene. By comparing our calculations to the present molecular dynamic simulation results, we expect our adsorption system is stable under room temperature and hydrogen can be released after moderate heating.

  17. Enhanced hydrogen storage by using lithium decoration on phosphorene

    NASA Astrophysics Data System (ADS)

    Yu, Zhiyuan; Wan, Neng; Lei, Shuangying; Yu, Hong

    2016-07-01

    The hydrogen storage characteristics of Li decorated phosphorene were systematically investigated based on first-principle density functional theory. It is revealed that the adsorption of H2 on pristine phosphorene is relatively weak with an adsorption energy of 0.06 eV. While this value can be dramatically enhanced to ˜0.2 eV after the phosphorene was decorated by Li, and each Li atom can adsorb up to three H2 molecules. The detailed mechanism of the enhanced hydrogen storage was discussed based on our density functional theory calculations. Our studies give a conservative prediction of hydrogen storage capacity to be 4.4 wt. % through Li decoration on pristine phosphorene. By comparing our calculations to the present molecular dynamic simulation results, we expect our adsorption system is stable under room temperature and hydrogen can be released after moderate heating.

  18. Characterization of hydrogen storage materials by means of pressure concentration isotherms based on the mass flow method

    NASA Astrophysics Data System (ADS)

    Bielmann, Michael; Kato, Shunsuke; Mauron, Philippe; Borgschulte, Andreas; Züttel, Andreas

    2009-08-01

    The determination of the equilibrium thermodynamic parameters of hydrogen storage materials from quasiequilibrium pressure data using the mass flow pressure concentration isotherm (pcI) method is presented. The method bases on the acquisition of pcI curves at different flow rates using a thermal mass flow controller to determine the amount of ad/desorbed hydrogen. These measurements provide a set of corresponding quasiequilibrium pressure functions from, which the true equilibrium pressure of the hydride is calculated by extrapolation to zero flow. The governing thermodynamic parameters can then be determined to characterize the material by the construction of a van't Hoff plot, extracting enthalpy of reaction ΔHr and entropy of reaction ΔSr from the equilibrium pressure peq as a function of temperature. Naturally, true equilibrium can never be reached and therefore can only be approximated by measurement--a drawback that all experimental techniques share. This complication is alleviated by the flow-pcI approach at different flow rates. The compilation of the peq(T ) data from pcI-measurements can be performed by different methods, whereas the so called Sieverts apparatus is most commonly used. In this paper, we elaborate the differences and advantages of the mass flow-pcI over the Sieverts Apparatus and present measurements and results on LaNi5 as a benchmark. Measurements at different flow rates are presented and equilibrium pressures at zero flow are achieved by extrapolation. The obtained results of ΔHd=32.5 kJ mol-1 H2 and ΔSd=115 J K-1 mol-1 H2 (desorption process) perfectly match literature values, emphasizing the excellent quality of the measurements and the performance of this measurement apparatus.

  19. Characterization of hydrogen storage materials by means of pressure concentration isotherms based on the mass flow method.

    PubMed

    Bielmann, Michael; Kato, Shunsuke; Mauron, Philippe; Borgschulte, Andreas; Züttel, Andreas

    2009-08-01

    The determination of the equilibrium thermodynamic parameters of hydrogen storage materials from quasiequilibrium pressure data using the mass flow pressure concentration isotherm (pcI) method is presented. The method bases on the acquisition of pcI curves at different flow rates using a thermal mass flow controller to determine the amount of ad/desorbed hydrogen. These measurements provide a set of corresponding quasiequilibrium pressure functions from, which the true equilibrium pressure of the hydride is calculated by extrapolation to zero flow. The governing thermodynamic parameters can then be determined to characterize the material by the construction of a van't Hoff plot, extracting enthalpy of reaction DeltaH(r) and entropy of reaction DeltaS(r) from the equilibrium pressure p(eq) as a function of temperature. Naturally, true equilibrium can never be reached and therefore can only be approximated by measurement--a drawback that all experimental techniques share. This complication is alleviated by the flow-pcI approach at different flow rates. The compilation of the p(eq)(T) data from pcI-measurements can be performed by different methods, whereas the so called Sieverts apparatus is most commonly used. In this paper, we elaborate the differences and advantages of the mass flow-pcI over the Sieverts Apparatus and present measurements and results on LaNi(5) as a benchmark. Measurements at different flow rates are presented and equilibrium pressures at zero flow are achieved by extrapolation. The obtained results of DeltaH(d)=32.5 kJ mol(-1) H(2) and DeltaS(d)=115 J K(-1) mol(-1) H(2) (desorption process) perfectly match literature values, emphasizing the excellent quality of the measurements and the performance of this measurement apparatus.

  20. Automotive storage of hydrogen in alane.

    SciTech Connect

    Ahluwalia, R. K.; Hua, T. Q.; Peng, J.-K.; Nuclear Engineering Division

    2009-09-01

    Although alane (AlH{sub 3}) has many interesting properties as a hydrogen storage material, it cannot be regenerated on-board a vehicle. One way of overcoming this limitation is to formulate an alane slurry that can be easily loaded into a fuel tank and removed for off-board regeneration. In this paper, we analyze the performance of an on-board hydrogen storage system that uses alane slurry as the hydrogen carrier. A model for the on-board storage system was developed to analyze the AlH{sub 3} decomposition kinetics, heat transfer requirements, stability, startup energy and time, H{sub 2} buffer requirements, storage efficiency, and hydrogen storage capacities. The results from the model indicate that reactor temperatures higher than 200 C are needed to decompose alane at reasonable liquid hourly space velocities, i.e., > 60 h{sup -1}. At the system level, a gravimetric capacity of 4.2 wt% usable hydrogen and a volumetric capacity of 50 g H{sub 2}/L may be achievable with a 70% solids slurry. Under optimum conditions, {approx}80% of the H{sub 2} stored in the slurry may be available for the fuel cell engine. The model indicates that H{sub 2} loss is limited by the decomposition kinetics rather than by the rate of heat transfer from the ambient to the slurry tank.

  1. Ti-MOFs for Hydrogen Storage

    NASA Astrophysics Data System (ADS)

    Sun, Q.; Li, S.; Wang, Q.; Jena, P.

    2007-03-01

    Recently, metal-organic frameworks (MOFs) have attracted considerable interest as hydrogen storage materials owing to their unique properties. Among MOFs, MOF-5 (Zn-MOF) is superior because of its high thermal stability, large surface area, and extra high porosity, which is ideal for gas storage applications. Can we improve the hydrogen uptake in MOF-5 by replacing Zn with different metal atoms? Experimentally, Cu-MOFs have already shown higher hydrogen uptake at low pressures compared with Zn-MOFs, which makes Cu-MOFs promising candidates for hydrogen storage. By means of first principles calculations, we have replaced Zn with Cu and Ti. Ti doping has already been introduced in C60 and carbon-nanotubes to improve hydrogen uptake. By comparing Zn, Cu and Ti, we found that Ti substitution presents the highest binding energy to H2 molecule, while Cu and Zn show similar binding energy to H2 molecule. Therefore, Ti-MOFs can be prospective materials for hydrogen storage applications.

  2. Modified lithium borohydrides for reversible hydrogen storage.

    PubMed

    Au, Ming; Jurgensen, Arthur

    2006-04-06

    In an attempt to develop lithium borohydrides as reversible hydrogen storage materials with high hydrogen storage capacities, the feasibility of reducing the dehydrogenation temperature of the lithium borohydride and moderating rehydrogenation conditions was explored. The lithium borohydride was modified by ball milling with metal oxides and metal chlorides as additives. The modified lithium borohydrides released 9 wt % hydrogen starting from 473 K. The dehydrided modified lithium borohydrides absorbed 7-9 wt % hydrogen at 873 K and 7 MPa. The modification with additives reduced the dehydriding starting temperature from 673 to 473 K and moderated the rehydrogenation conditions from 923 K/15 MPa to 873 K/7 MPa. XRD and SEM analysis revealed the formation of an intermediate compound that might play a key role in changing the reaction path, resulting in the lower dehydriding temperature and reversibility. The reversible hydrogen storage capacity of the oxide-modified lithium borohydrides decreased gradually during hydriding/dehydriding cycling. One of the possible reasons for this effect might be the loss of boron during dehydrogenation, but this can be prevented by changing the dehydriding path using appropriate additives. The additives reduced the dehydriding temperature and improved the reversibility, but they also reduced the hydrogen storage capacity. The best compromise can be reached by selecting appropriate additives, optimizing the additive loading, and using new synthesis processes other than ball milling.

  3. ALUMINUM HYDRIDE: A REVERSIBLE STORAGE MATERIAL FOR HYDROGEN STORAGE

    SciTech Connect

    Zidan, R; Christopher Fewox, C; Brenda Garcia-Diaz, B; Joshua Gray, J

    2009-01-09

    One of the challenges of implementing the hydrogen economy is finding a suitable solid H{sub 2} storage material. Aluminium (alane, AlH{sub 3}) hydride has been examined as a potential hydrogen storage material because of its high weight capacity, low discharge temperature, and volumetric density. Recycling the dehydride material has however precluded AlH{sub 3} from being implemented due to the large pressures required (>10{sup 5} bar H{sub 2} at 25 C) and the thermodynamic expense of chemical synthesis. A reversible cycle to form alane electrochemically using NaAlH{sub 4} in THF been successfully demonstrated. Alane is isolated as the triethylamine (TEA) adduct and converted to unsolvated alane by heating under vacuum. To complete the cycle, the starting alanate can be regenerated by direct hydrogenation of the dehydrided alane and the alkali hydride (NaH) This novel reversible cycle opens the door for alane to fuel the hydrogen economy.

  4. Development of Automotive Liquid Hydrogen Storage Systems

    NASA Astrophysics Data System (ADS)

    Krainz, G.; Bartlok, G.; Bodner, P.; Casapicola, P.; Doeller, Ch.; Hofmeister, F.; Neubacher, E.; Zieger, A.

    2004-06-01

    Liquid hydrogen (LH2) takes up less storage volume than gas but requires cryogenic vessels. State-of-the-art applications for passenger vehicles consist of double-wall cylindrical tanks that hold a hydrogen storage mass of up to 10 kg. The preferred shell material of the tanks is stainless steel, since it is very resistant against hydrogen brittleness and shows negligible hydrogen permeation. Therefore, the weight of the whole tank system including valves and heat exchanger is more than 100 kg. The space between the inner and outer vessel is mainly used for thermal super-insulation purposes. Several layers of insulation foils and high vacuums of 10-3 Pa reduce the heat entry. The support structures, which keep the inner tank in position to the outer tank, are made of materials with low thermal conductivity, e.g. glass or carbon fiber reinforced plastics. The remaining heat in-leak leads to a boil-off rate of 1 to 3 percent per day. Active cooling systems to increase the stand-by time before evaporation losses occur are being studied. Currently, the production of several liquid hydrogen tanks that fulfill the draft of regulations of the European Integrated Hydrogen Project (EIHP) is being prepared. New concepts of lightweight liquid hydrogen storage tanks will be investigated.

  5. High-capacity hydrogen storage in Al-adsorbed graphene

    NASA Astrophysics Data System (ADS)

    Ao, Z. M.; Peeters, F. M.

    2010-05-01

    A high-capacity hydrogen storage medium—Al-adsorbed graphene—is proposed based on density-functional theory calculations. We find that a graphene layer with Al adsorbed on both sides can store hydrogen up to 13.79wt% with average adsorption energy -0.193eV/H2 . Its hydrogen storage capacity is in excess of 6wt% , surpassing U. S. Department of Energy (DOE’s) target. Based on the binding-energy criterion and molecular-dynamics calculations, we find that hydrogen storage can be recycled at near ambient conditions. This high-capacity hydrogen storage is due to the adsorbed Al atoms that act as bridges to link the electron clouds of the H2 molecules and the graphene layer. As a consequence, a two-layer arrangement of H2 molecules is formed on each side of the Al-adsorbed graphene layer. The H2 concentration in the hydrogen storage medium can be measured by the change in the conductivity of the graphene layer.

  6. Simultaneous purification and storage of hydrogen

    SciTech Connect

    Hynek, S.; Fuller, W.; Weber, R.; Carlson, E.

    1998-08-01

    Specially coated magnesium particles have been shown to selectively absorb hydrogen from a hydrogen-rich gas stream such as reformate. These coated magnesium particles can store the absorbed hydrogen as required and subsequently deliver pure hydrogen, just as uncoated magnesium particles can. These coated magnesium particles could be used in a device that accepts a steady stream of reformate, as from a methane reformer, stores the selectively absorbed hydrogen indefinitely, and delivers purified hydrogen on demand. Unfortunately, this coating (magnesium nitride) has been shown to degrade over a period of several weeks, so that the magnesium within evidences progressively lower storage capacity. The authors are investigating two other coatings, one of which might be applicable to hydridable metals other than magnesium, to replace magnesium nitride.

  7. Hydrogen Storage and Production Project

    SciTech Connect

    Bhattacharyya, Abhijit; Biris, A. S.; Mazumder, M. K.; Karabacak, T.; Kannarpady, Ganesh; Sharma, R.

    2011-07-31

    This is the final technical report. This report is a summary of the project. The goal of our project is to improve solar-to-hydrogen generation efficiency of the PhotoElectroChemical (PEC) conversion process by developing photoanodes with high absorption efficiency in the visible region of the solar radiation spectrum and to increase photo-corrosion resistance of the electrode for generating hydrogen from water. To meet this goal, we synthesized nanostructured heterogeneous semiconducting photoanodes with a higher light absorption efficiency compared to that of TiO2 and used a corrosion protective layer of TiO2. While the advantages of photoelectrochemical (PEC) production of hydrogen have not yet been realized, the recent developments show emergence of new nanostructural designs of photoanodes and choices of materials with significant gains in photoconversion efficiency.

  8. A single-component liquid-phase hydrogen storage material.

    PubMed

    Luo, Wei; Campbell, Patrick G; Zakharov, Lev N; Liu, Shih-Yuan

    2011-12-07

    The current state-of-the-art for hydrogen storage is compressed H(2) at 700 bar. The development of a liquid-phase hydrogen storage material has the potential to take advantage of the existing liquid-based distribution infrastructure. We describe a liquid-phase hydrogen storage material that is a liquid under ambient conditions (i.e., at 20 °C and 1 atm pressure), air- and moisture-stable, and recyclable; releases H(2) controllably and cleanly at temperatures below or at the proton exchange membrane fuel cell waste-heat temperature of 80 °C; utilizes catalysts that are cheap and abundant for H(2) desorption; features reasonable gravimetric and volumetric storage capacity; and does not undergo a phase change upon H(2) desorption. © 2011 American Chemical Society

  9. Polyaniline-polypyrrole composites with enhanced hydrogen storage capacities.

    PubMed

    Attia, Nour F; Geckeler, Kurt E

    2013-06-13

    A facile method for the synthesis of polyaniline-polypyrrole composite materials with network morphology is developed based on polyaniline nanofibers covered by a thin layer of polypyrrole via vapor phase polymerization. The hydrogen storage capacity of the composites is evaluated at room temperature exhibits a twofold increase in hydrogen storage capacity. The HCl-doped polyaniline nanofibers exhibit a storage capacity of 0.46 wt%, whereas the polyaniline-polypyrrole composites could store 0.91 wt% of hydrogen gas. In addition, the effect of the dopant type, counteranion size, and the doping with palladium nanoparticles on the storage properties are also investigated. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Nickel-hydrogen capacity loss on storage

    NASA Technical Reports Server (NTRS)

    Manzo, Michelle A.

    1989-01-01

    Nickel-hydrogen batteries are rapidly becoming accepted for use in low-earth-orbit and geosynchronous orbit applications. With their increased use it has become evident that the storage procedures commonly used for nickel-cadmium cells are not adequate for the nickel-hydrogen system. The capacity loss exhibited by nickel electrodes from various manufacturers when exposed to different storage conditions was determined. A comprehensive test matrix was developed to evaluate capacity loss in nickel electrodes from four different manufacturers. Two types of tests were run; individual electrode tests, which involved flooded capacity and impedance measurements before and after storage under varied conditions of temperature, hydrogen pressure, and electrolyte concentration; and cell tests which primarily evaluated the effects of state-of-charge on storage. The cell tests evaluated capacity loss on cells stored open circuit, shorted and trickle charged at C/100 following a full charge. The results indicate that capacity loss varies with the specific electrode manufacturing process, storage temperature and hydrogen pressure. In general, electrodes stored at low temperatures or low hydrogen pressures exhibited a smaller loss in capacity over the twenty-eight day storage period than those stored at high pressure and high temperature. The capacity loss appears to correlate with the level of cobalt in the nickel electrode, with the most significant loss of capacity occurring in electrodes with higher cobalt levels. Impedance measurements appear to correlate well with the capacity loss observed for a given type of electrode but do not correlate well with the capacity loss between electrodes fabricated by different manufacturers. There was a definite correlation between the electrode potential measured immediately following storage and the measured capacity loss.

  11. Porous polymeric materials for hydrogen storage

    DOEpatents

    Yu, Luping [Hoffman Estates, IL; Liu, Di-Jia [Naperville, IL; Yuan, Shengwen [Chicago, IL; Yang, Junbing [Westmont, IL

    2011-12-13

    Porous polymers, tribenzohexazatriphenylene, poly-9,9'-spirobifluorene, poly-tetraphenyl methane and their derivatives for storage of H.sub.2 prepared through a chemical synthesis method. The porous polymers have high specific surface area and narrow pore size distribution. Hydrogen uptake measurements conducted for these polymers determined a higher hydrogen storage capacity at the ambient temperature over that of the benchmark materials. The method of preparing such polymers, includes oxidatively activating solids by CO.sub.2/steam oxidation and supercritical water treatment.

  12. Multi-component hydrogen storage material

    DOEpatents

    Faheem, Syed A.; Lewis, Gregory J.; Sachtler, J.W. Adriaan; Low, John J.; Lesch, David A.; Dosek, Paul M.; Wolverton, Christopher M.; Siegel, Donald J.; Sudik, Andrea C.; Yang, Jun

    2010-09-07

    A reversible hydrogen storage composition having an empirical formula of: Li.sub.(x+z)N.sub.xMg.sub.yB.sub.zH.sub.w where 0.4.ltoreq.x.ltoreq.0.8; 0.2.ltoreq.y.ltoreq.0.6; 0hydrogen storage compared to binary systems such as MgH.sub.2--LiNH.sub.2.

  13. Capacity retention in hydrogen storage alloys

    NASA Technical Reports Server (NTRS)

    Anani, A.; Visintin, A.; Srinivasan, S.; Appleby, A. J.; Reilly, J. J.; Johnson, J. R.

    1992-01-01

    Results of our examination of the properties of several candidate materials for hydrogen storage electrodes and their relation to the decrease in H-storage capacity upon open-circuit storage over time are reported. In some of the alloy samples examined to date, only about 10 percent of the hydrogen capacity was lost upon storage for 20 days, while in others, this number was as high as 30 percent for the same period of time. This loss in capacity is attributed to two separate mechanisms: (1) hydrogen desorbed from the electrode due to pressure differences between the cell and the electrode sample; and (2) chemical and/or electrochemical degradation of the alloy electrode upon exposure to the cell environment. The former process is a direct consequence of the equilibrium dissociation pressure of the hydride alloy phase and the partial pressure of hydrogen in the hydride phase in equilibrium with that in the electrolyte environment, while the latter is related to the stability of the alloy phase in the cell environment. Comparison of the equilibrium gas-phase dissociation pressures of these alloys indicate that reversible loss of hydrogen capacity is higher in alloys with P(eqm) greater than 1 atm than in those with P(eqm) less than 1 atm.

  14. Hydrogen storage in graphite nanofibers

    SciTech Connect

    Park, C.; Tan, C.D.; Hidalgo, R.; Baker, R.T.K.; Rodriguez, N.M.

    1998-08-01

    Graphite nanofibers (GNF) are a type of material that is produced by the decomposition of carbon containing gases over metal catalyst particles at temperatures around 600 C. These molecularly engineered structures consist of graphene sheets perfectly arranged in a parallel, perpendicular or at angle orientation with respect to the fiber axis. The most important feature of the material is that only edges are exposed. Such an arrangement imparts the material with unique properties for gas adsorption because the evenly separated layers constitute the most ordered set of nanopores that can accommodate an adsorbate in the most efficient manner. In addition, the non-rigid pore walls can also expand so as to accommodate hydrogen in a multilayer conformation. Of the many varieties of structures that can be produced the authors have discovered that when gram quantities of a selected number of GNF are exposed to hydrogen at pressures of {approximately} 2,000 psi, they are capable of adsorbing and storing up to 40 wt% of hydrogen. It is believed that a strong interaction is established between hydrogen and the delocalized p-electrons present in the graphite layers and therefore a new type of chemistry is occurring within these confined structures.

  15. Hydrogen Storage in Novel Molecular Materials, Final Report

    SciTech Connect

    Viktor V. Struzhkin; Wendy L. Mao; Ho-Kwang Mao; Burkhard Militzer; Russell Hemley

    2006-05-31

    This project is conducting fundamental studies of inorganic H2 clathrates (H2O- and CH4- based). Insights gained from these studies could be applied toward the design and synthesis of hydrogen storage materials that meet the DOE 2010 hydrogen storage targets, especially cost, specific energy, energy density, environmental cleanliness, and safety of hydrogen storage. We have synthesized clathrates with very high H2 contents in diamond anvil cells at high pressure and low temperature; clathrate formation and hydrogen release are spontaneous. The hydrogen clathrate structures have been synthesized at 300 MPa and 250 K with hydrogen weight content about 5%. This clathrate structure (sII) is stable at ambient pressure up to 80 K. The major technical issue is to extend the P-T stability field to near ambient P and T. Our approach is to explore H2-CH4-X and H2-H2O-X systems experimentally and theoretically to find additional components X (promoters ) that will stabilize existing large-cage clathrate structures, and to look for new clathrate structures with even larger hydrogen storage capacity. Most of the experimental studies performed by our group and other researchers have been concentrated on X=THF (tetrahydrofurane molecule).

  16. Development of Hydrogen Storage Tank Systems Based on Complex Metal Hydrides

    PubMed Central

    Ley, Morten B.; Meggouh, Mariem; Moury, Romain; Peinecke, Kateryna; Felderhoff, Michael

    2015-01-01

    This review describes recent research in the development of tank systems based on complex metal hydrides for thermolysis and hydrolysis. Commercial applications using complex metal hydrides are limited, especially for thermolysis-based systems where so far only demonstration projects have been performed. Hydrolysis-based systems find their way in space, naval, military and defense applications due to their compatibility with proton exchange membrane (PEM) fuel cells. Tank design, modeling, and development for thermolysis and hydrolysis systems as well as commercial applications of hydrolysis systems are described in more detail in this review. For thermolysis, mostly sodium aluminum hydride containing tanks were developed, and only a few examples with nitrides, ammonia borane and alane. For hydrolysis, sodium borohydride was the preferred material whereas ammonia borane found less popularity. Recycling of the sodium borohydride spent fuel remains an important part for their commercial viability. PMID:28793541

  17. Development of Hydrogen Storage Tank Systems Based on Complex Metal Hydrides.

    PubMed

    Ley, Morten B; Meggouh, Mariem; Moury, Romain; Peinecke, Kateryna; Felderhoff, Michael

    2015-09-04

    This review describes recent research in the development of tank systems based on complex metal hydrides for thermolysis and hydrolysis. Commercial applications using complex metal hydrides are limited, especially for thermolysis-based systems where so far only demonstration projects have been performed. Hydrolysis-based systems find their way in space, naval, military and defense applications due to their compatibility with proton exchange membrane (PEM) fuel cells. Tank design, modeling, and development for thermolysis and hydrolysis systems as well as commercial applications of hydrolysis systems are described in more detail in this review. For thermolysis, mostly sodium aluminum hydride containing tanks were developed, and only a few examples with nitrides, ammonia borane and alane. For hydrolysis, sodium borohydride was the preferred material whereas ammonia borane found less popularity. Recycling of the sodium borohydride spent fuel remains an important part for their commercial viability.

  18. Activated aluminum hydride hydrogen storage compositions and uses thereof

    DOEpatents

    Sandrock, Gary; Reilly, James; Graetz, Jason; Wegrzyn, James E.

    2010-11-23

    In one aspect, the invention relates to activated aluminum hydride hydrogen storage compositions containing aluminum hydride in the presence of, or absence of, hydrogen desorption stimulants. The invention particularly relates to such compositions having one or more hydrogen desorption stimulants selected from metal hydrides and metal aluminum hydrides. In another aspect, the invention relates to methods for generating hydrogen from such hydrogen storage compositions.

  19. Hydrogen storage via polyhydride complexes

    SciTech Connect

    Jensen, C.M.; Zidan, R.A.

    1998-08-01

    The reversible dehydrogenation of NaAlH{sub 4} is catalyzed in toluene slurries of the NaAlH{sub 4} containing the pincer complex, IrH{sub 4} {l_brace}C{sub 6}H{sub 3}-2,6-(CH{sub 2}PBu{sup t}{sub 2}){sub 2}{r_brace}. The rates of the pincer complex catalyzed dehydrogenation are about five times greater those previously found for NaAlH{sub 4} that was doped with titanium through a wet chemistry method. Homogenization of NaAlH{sub 4} with 2 mole % Ti(OBu{sup n}){sub 4} under an atmosphere of argon produces a novel titanium containing material. TPD measurements show that the dehydrogenation of this material occurs about 30 C lower than that previously found for wet titanium doped NaAlH{sub 4}. In further contrast to wet doped NaAlH{sub 4}, the dehydrogenation kinetics and hydrogen capacity of the novel material are undiminished over several dehydriding/hydriding cycles. Rehydrogenation of the titanium doped material occurs readily at 170 C under 150 atm of hydrogen. TPD measurements show that about 80% of the original hydrogen content (4.2 wt%) can be restored under these conditions.

  20. Effects of magnesium-based hydrogen storage materials on the thermal decomposition, burning rate, and explosive heat of ammonium perchlorate-based composite solid propellant.

    PubMed

    Liu, Leili; Li, Jie; Zhang, Lingyao; Tian, Siyu

    2017-08-24

    MgH2, Mg2NiH4, and Mg2CuH3 were prepared, and their structure and hydrogen storage properties were determined through X-ray photoelectron spectroscopy and thermal analyzer. The effects of MgH2, Mg2NiH4, and Mg2CuH3 on the thermal decomposition, burning rate, and explosive heat of ammonium perchlorate-based composite solid propellant were subsequently studied. Results indicated that MgH2, Mg2NiH4, and Mg2CuH3 can decrease the thermal decomposition peak temperature and increase the total released heat of decomposition. These compounds can improve the effect of thermal decomposition of the propellant. The burning rates of the propellant increased using Mg-based hydrogen storage materials as promoter. The burning rates of the propellant also increased using MgH2 instead of Al in the propellant, but its explosive heat was not enlarged. Nonetheless, the combustion heat of MgH2 was higher than that of Al. A possible mechanism was thus proposed. Copyright © 2017. Published by Elsevier B.V.

  1. First-principles prediction of high-capacity, thermodynamically reversible hydrogen storage reactions based on (NH4)2B12H12

    NASA Astrophysics Data System (ADS)

    Sun, Wenhao Q.; Wolverton, C.; Akbarzadeh, A. R.; Ozolins, V.

    2011-02-01

    We use a combination of first-principles density functional calculations along with the recently developed grand canonical linear programing method to predict a novel, high-capacity hydrogen storage reaction with thermodynamics suitable for near-ambient reversible storage. Unlike the vast majority of previously proposed complex hydrides, which typically rely on a hydrogen-containing anionic unit, our reaction is based on an ammonium-containing hydride, (NH4)2B12H12, which contains increased storage capacity due to both anionic and cationic hydrogen-containing complexes. The predicted decomposition of this hydride is a two-step reaction sequence: (NH4)2B12H12 → 2BN + ½B20H16 + 6H2 →2BN + 10B + 10H2, which possesses a theoretical gravimetric capacity of 11.3 wt% H2, a single-crystal volumetric density of 52 g H2/L, and T=300 K reaction enthalpies of 17 and 33 kJ/mol H2, respectively, which are well-suited for near-ambient reversible storage. The combination of these three attributes in a single material makes this decomposition reaction sequence highly promising.

  2. Hydrogen storage in metal-hydrogen systems and their derivatives

    NASA Astrophysics Data System (ADS)

    Eberle, U.; Arnold, G.; von Helmolt, R.

    During the last years, the power densities of automotive fuel cell systems have been raised dramatically. However, a major technology improvement is still needed for the on-board fuel storage system since hydrogen exhibits a rather low volumetric energy density (regardless whether it is stored as a liquid at cryogenic temperatures or as a compressed gas). Furthermore, the cost for current hydrogen containers is far from what gasoline tanks cost. Therefore, alternatives like solid-state absorbers of hydrogen (e.g. metal hydrides or complex hydrides) are investigated for their feasibility by the car industry. These kinds of systems show very high volumetric storage densities on a materials basis. Unfortunately, the host compounds are usually quite heavy and thus possess a low gravimetric storage density. Also, the thermodynamics and kinetics of the absorption/desorption reactions and their impact on the tank design in general (and on the heat management in particular) have to be considered. Within the framework of this paper, the properties of the most promising solid-state storage systems are discussed and compared to those of the liquid and compressed gaseous hydrogen technologies.

  3. Tuning the Hydrogen Storage in Magnesium Alloys

    NASA Astrophysics Data System (ADS)

    Er, Suleyman; de Wijs, Gilles A.; Brocks, Geert

    2011-03-01

    We investigate the hydrogen storage properties of promising magnesium alloys. Mg H2 (7.6 wt % H) would be a very useful storage material if the (de)hydrogenation kinetics can be improved and the desorption temperature is markedly lowered. Using first principles calculations, we show that hydrides of Mg-transition metal (TM) alloys adopt a structure that promotes faster (de)hydrogenation kinetics, as is also observed in experiment. Within the lightweight TMs, the most promising alloying element is titanium. Alloying Mg with Ti alone, however, is not sufficient to decrease the stability of the hydride phases, which is necessary to reduce the hydrogen desorption temperature. We find that adding aluminium or silicon markedly destabilizes Mg-Ti hydrides and stabilizes Mg-Ti alloys. Finally, we show that controlling the structure of Mg-Ti-Al(Si) system by growing it as multilayers, has a beneficial influence on the thermodynamic properties and makes it a stronger candidate for hydrogen storage.

  4. Modified borohydrides for reversible hydrogen storage

    SciTech Connect

    Au, Ming

    2005-08-29

    In attempt to develop lithium borohydrides as the reversible hydrogen storage materials with the high capacity, the feasibility to reduce dehydrogenation temperature of the lithium borohydride and moderate rehydrogenation condition has been explored. The commercial available lithium borohydride has been modified by ball milling with metal oxides and metal chlorides as the additives. The modified lithium borohydrides release 9 wt% hydrogen starting from 473K. The dehydrided modified lithium borohydrides absorb 7-9 wt% hydrogen at 873K and 7 MPa. The additive modification reduces dehydriding temperature from 673K to 473K and moderates rehydrogenation conditions to 923K and 15 MPa. XRD and SEM analysis discovered the formation of the intermediate compound TiB{sub 2} that may plays the key role in change the reaction path resulting the lower dehydriding temperature and reversibility. The reversible hydrogen storage capacity of the oxide modified lithium borohydrides decreases gradually during hydriding-dehydriding cycling due to the lost of the boron during dehydrogenation. But, it can be prevented by selecting the suitable additive, forming intermediate boron compounds and changing the reaction path. The additives reduce dehydriding temperature and improve the reversibility, it also reduces the hydrogen storage capacity. The best compromise can be reached by optimization of the additive loading and introducing new process other than ball milling.

  5. Flexible bulb large storage box hydrogen maser

    NASA Technical Reports Server (NTRS)

    Reinhardt, V.

    1973-01-01

    The principal limitation on the accuracy of the hydrogen maser as a primary frequency standard has been the irreproducibility of the frequency shift caused by collisions of the radiating atoms with the walls of the vessel containing them. The flexible bulb-large storage box hydrogen maser allows correction for this wall shift within a single device, sidestepping the reproducibility problem, and reducing the frequency error from the wall shift to the level imposed by the device's stability. The principles of the device are discussed including the flexible bulb technique and the complications caused by a multiple region storage bulb. The stability of the device is discussed including a comparison with an ordinary hydrogen maser. Data is presented from a working flexible bulb-large storage box hydrogen maser demonstrating the feasibility of the device and showing some of its operating characteristics. The flexibility of the device is demonstrated by showing how the device's added degrees of freedom allow measurement of parameters unmeasurable in an ordinary hydrogen maser.

  6. A kinetics study on promising hydrogen storage properties of Mg-based thin films at room temperature.

    PubMed

    Qu, Jianglan; Liu, Yang; Xin, Gongbiao; Zheng, Jie; Li, Xingguo

    2014-04-21

    Pd-Mg-Pd thin films with variable thickness of Mg layers were prepared. Their optical and electrical changes in both gasochromic and chemochromic processes were compared to investigate the kinetics of Mg-based thin films at room temperature. Hydrogen absorption and desorption kinetics of Pd-Mg-Pd thin films were strongly dependent on the thickness of the Mg layer. Especially, when the thickness was lowered to 60 nm, a MgH2 layer formed immediately after exposure to H2 at room temperature, while a Mg layer was rapidly generated during hydrogen desorption in ambient air. By means of optical and electrical resistance measurements, we found that the diffusion process contributed significantly to hydrogen absorption and desorption. The remarkable absorption and desorption kinetics at room temperature reported here suggested promising applications in Mg-based energy-efficient devices and hydrogen sensors.

  7. Metal-functionalized silicene for efficient hydrogen storage.

    PubMed

    Hussain, Tanveer; Chakraborty, Sudip; Ahuja, Rajeev

    2013-10-21

    First-principles calculations based on density functional theory are used to investigate the electronic structure along with the stability, bonding mechanism, band gap, and charge transfer of metal-functionalized silicene to envisage its hydrogen-storage capacity. Various metal atoms including Li, Na, K, Be, Mg, and Ca are doped into the most stable configuration of silicene. The corresponding binding energies and charge-transfer mechanisms are discussed from the perspective of hydrogen-storage compatibility. The Li and Na metal dopants are found to be ideally suitable, not only for strong metal-to-substrate binding and uniform distribution over the substrate, but also for the high-capacity storage of hydrogen. The stabilities of both Li- and Na-functionalized silicene are also confirmed through molecular dynamics simulations. It is found that both of the alkali metals, Li(+) and Na(+), can adsorb five hydrogen molecules, attaining reasonably high storage capacities of 7.75 and 6.9 wt %, respectively, with average adsorption energies within the range suitable for practical hydrogen-storage applications. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. NREL Advances Spillover Materials for Hydrogen Storage (Fact Sheet)

    SciTech Connect

    Not Available

    2010-12-01

    This fact sheet describes NREL's accomplishments in advancing spillover materials for hydrogen storage and improving the reproducible synthesis, long-term durability, and material costs of hydrogen storage materials. Work was performed by NREL's Chemical and Materials Science Center.

  9. Synthesis, characterization and hydrogen storage studies on porous carbon

    NASA Astrophysics Data System (ADS)

    Ruz, Priyanka; Banerjee, Seemita; Pandey, M.; Sudarsan, V.

    2015-06-01

    Porous carbon sample has been prepared, using zeolite-Y as template followed by annealing at 800°C, with view to estimate the extent of hydrogen storage by the sample. Based on XRD, 13C MAS NMR and Raman spectroscopic studies it is confirmed that the porous Carbon sample contains only sp2 hybridized carbon. The hydrogen sorption isotherms have been recorded for the sample at 273, 223K and 123K and the maximum hydrogen absorption capacity is found to be 1.47wt% at 123K. The interaction energy of hydrogen with the carbon framework was determined to be ˜ 10 kJ mol-1at lower hydrogen uptake and gradually decreases with increase in hydrogen loading.

  10. Synthesis, characterization and hydrogen storage studies on porous carbon

    SciTech Connect

    Ruz, Priyanka Banerjee, Seemita; Sudarsan, V.; Pandey, M.

    2015-06-24

    Porous carbon sample has been prepared, using zeolite-Y as template followed by annealing at 800°C, with view to estimate the extent of hydrogen storage by the sample. Based on XRD, {sup 13}C MAS NMR and Raman spectroscopic studies it is confirmed that the porous Carbon sample contains only sp{sup 2} hybridized carbon. The hydrogen sorption isotherms have been recorded for the sample at 273, 223K and 123K and the maximum hydrogen absorption capacity is found to be 1.47wt% at 123K. The interaction energy of hydrogen with the carbon framework was determined to be ∼ 10 kJ mol{sup −1}at lower hydrogen uptake and gradually decreases with increase in hydrogen loading.

  11. On the Reversibility of Hydrogen Storage in Novel Complex Hydrides

    DTIC Science & Technology

    2004-06-01

    On the Reversibility of Hydrogen Storage in Novel Complex Hydrides JUN WANG, ARMIN D. EBNER AND JAMES A. RITTER Department of Chemical...potential hydrogen storage materials, it remains that only Ti-doped NaAlH4 exhibits around 3 wt % reversibility under reasonable conditions...Keywords: Titanium Chloride, Hydrogen Storage , Sodium Alanate, Lithium Alanate, Magnesium Alanate Introduction Hydrogen storage is proving to

  12. Standardized Testing Program for Solid-State Hydrogen Storage Technologies

    SciTech Connect

    Miller, Michael A.; Page, Richard A.

    2012-07-30

    In the US and abroad, major research and development initiatives toward establishing a hydrogen-based transportation infrastructure have been undertaken, encompassing key technological challenges in hydrogen production and delivery, fuel cells, and hydrogen storage. However, the principal obstacle to the implementation of a safe, low-pressure hydrogen fueling system for fuel-cell powered vehicles remains storage under conditions of near-ambient temperature and moderate pressure. The choices for viable hydrogen storage systems at the present time are limited to compressed gas storage tanks, cryogenic liquid hydrogen storage tanks, chemical hydrogen storage, and hydrogen absorbed or adsorbed in a solid-state material (a.k.a. solid-state storage). Solid-state hydrogen storage may offer overriding benefits in terms of storage capacity, kinetics and, most importantly, safety.The fervor among the research community to develop novel storage materials had, in many instances, the unfortunate consequence of making erroneous, if not wild, claims on the reported storage capacities achievable in such materials, to the extent that the potential viability of emerging materials was difficult to assess. This problem led to a widespread need to establish a capability to accurately and independently assess the storage behavior of a wide array of different classes of solid-state storage materials, employing qualified methods, thus allowing development efforts to focus on those materials that showed the most promise. However, standard guidelines, dedicated facilities, or certification programs specifically aimed at testing and assessing the performance, safety, and life cycle of these emergent materials had not been established. To address the stated need, the Testing Laboratory for Solid-State Hydrogen Storage Technologies was commissioned as a national-level focal point for evaluating new materials emerging from the designated Materials Centers of Excellence (MCoE) according to

  13. Materials for Hydrogen Storage: From Complex Hydrides to Functionalized Nanostructures

    NASA Astrophysics Data System (ADS)

    Das, G. P.

    2011-07-01

    The world wide effort for a transition to renewable and clean (i.e. carbon-free) form of energy has resulted in an upsurge of interest in harnessing and utilizing Hydrogen. Apart from being the most abundant element in the universe, hydrogen offers many advantages over other fuels: it is non-toxic, clean to use, and packs more energy per mass than any other fuel. Hydrogen energy production, storage and distribution constitute a multi-disciplinary area of research. Coming to the material issues for solid state storage of hydrogen, the most desirable criteria are high storage capacity, satisfactory kinetics, and optimal thermodynamics. Complex hydrides involving light metals, such as Alanates, Imides, Borates, Amidoboranes etc. show impressive gravimetric efficiencies, although the hydrogen desorption temperatures turn out to be rather high. Apart from complex hydrides, there are other kinds of novel materials that have been investigated, e.g. carbon based materials activated with nano-catalysts, clathrate hydrates, metal-organic complexes, and more recently nanostructured cages viz. fullerenes and nanotubes decorated with simple or transition metals that serve to attract hydrogen in molecular form. In this talk, after giving a broad overview on hydrogen economy, I shall focus on first-principles design of materials for hydrogen storage, from complex hydrides to various kinds of functinalized nanostructures, and discuss the recent results obtained in our laboratory [1-6]. Some outstanding issues and challenges, like how to circumvent the problem of metal clustering on surface, or how to bring down the hydrogen desorption temperature etc. will be discussed.

  14. Vehicular hydrogen storage using lightweight tanks

    SciTech Connect

    Mitlitsky, F; Weisberg, A H; Myers, B

    2000-07-22

    Lightweight hydrogen storage for vehicles is enabled by adopting and adapting aerospace tankage technology. The weight, volume, and cost are already acceptable and improving. Prototype tankage was demonstrated with 11.3% hydrogen by weight, 1.74 million inch (44.3 km) burst performance factor (P{sub b}V/W), and 3.77 kWh/kg specific energy for the tank and hydrogen (LHV). DOE cannot afford full scale aerospace development costs. For example, it costs many tens of $M to develop a rocket motor casing with a safety factor (SF) of 1.25. Large teams of experts are required to design, develop, and test new processes. Car companies are buying existing technology with only modest investments in research and development (R&D). The Lawrence Livermore National Laboratory (LLNL) team is maximizing the leverage from DOE funding by joining with industry to solve technical risks at the component level. LLNL is developing fabrication processes with IMPCO Technologies, Thiokol Propulsion, and Aero Tec Laboratories (ATL). LLNL is creating commercial products that are close to adoption under DOE solicitation. LLNL is breaking ground to achieve greater than 10% hydrogen by weight tankage with safety that exceeds the requirements of NGV2 standards modified for hydrogen. Risk reduction is proceeding along three axes: (1) Commercializable products will be available next year with {approx}90% confidence; (2) R&D progress is pushing the envelope in lightweight tankage for vehicles; and (3) Integration challenges are being met with partners in industry and DOE demo programs. This project is a key part of LLNL's effort to develop high cycle life energy storage systems with >600 Wh/kg specific energy for various applications, including: high altitude long endurance solar rechargeable aircraft, zero emission vehicles, hybrid energy storage/propulsion systems for spacecraft, energy storage for premium power, remote power sources, and peak shaving.

  15. Hydrogen-air energy storage gas-turbine system

    NASA Astrophysics Data System (ADS)

    Schastlivtsev, A. I.; Nazarova, O. V.

    2016-02-01

    A hydrogen-air energy storage gas-turbine unit is considered that can be used in both nuclear and centralized power industries. However, it is the most promising when used for power-generating plants based on renewable energy sources (RES). The basic feature of the energy storage system in question is combination of storing the energy in compressed air and hydrogen and oxygen produced by the water electrolysis. Such a process makes the energy storage more flexible, in particular, when applied to RES-based power-generating plants whose generation of power may considerably vary during the course of a day, and also reduces the specific cost of the system by decreasing the required volume of the reservoir. This will allow construction of such systems in any areas independent of the local topography in contrast to the compressed-air energy storage gas-turbine plants, which require large-sized underground reservoirs. It should be noted that, during the energy recovery, the air that arrives from the reservoir is heated by combustion of hydrogen in oxygen, which results in the gas-turbine exhaust gases practically free of substances hazardous to the health and the environment. The results of analysis of a hydrogen-air energy storage gas-turbine system are presented. Its layout and the principle of its operation are described and the basic parameters are computed. The units of the system are analyzed and their costs are assessed; the recovery factor is estimated at more than 60%. According to the obtained results, almost all main components of the hydrogen-air energy storage gas-turbine system are well known at present; therefore, no considerable R&D costs are required. A new component of the system is the H2-O2 combustion chamber; a difficulty in manufacturing it is the necessity of ensuring the combustion of hydrogen in oxygen as complete as possible and preventing formation of nitric oxides.

  16. Metastable Metal Hydrides for Hydrogen Storage

    DOE PAGES

    Graetz, Jason

    2012-01-01

    The possibility of using hydrogen as a reliable energy carrier for both stationary and mobile applications has gained renewed interest in recent years due to improvements in high temperature fuel cells and a reduction in hydrogen production costs. However, a number of challenges remain and new media are needed that are capable of safely storing hydrogen with high gravimetric and volumetric densities. Metal hydrides and complex metal hydrides offer some hope of overcoming these challenges; however, many of the high capacity “reversible” hydrides exhibit a large endothermic decomposition enthalpy making it difficult to release the hydrogen at low temperatures. Onmore » the other hand, the metastable hydrides are characterized by a low reaction enthalpy and a decomposition reaction that is thermodynamically favorable under ambient conditions. The rapid, low temperature hydrogen evolution rates that can be achieved with these materials offer much promise for mobile PEM fuel cell applications. However, a critical challenge exists to develop new methods to regenerate these hydrides directly from the reactants and hydrogen gas. This spotlight paper presents an overview of some of the metastable metal hydrides for hydrogen storage and a few new approaches being investigated to address the key challenges associated with these materials.« less

  17. Nickel-hydrogen capacity loss on storage

    NASA Technical Reports Server (NTRS)

    Manzo, Michelle A.

    1990-01-01

    A controlled experiment evaluating the capacity loss experienced by nickel electrodes stored under various conditions of temperature, hydrogen pressure, and electrolyte concentration was conducted using nickel electrodes from four different manufacturers. It was found that capacity loss varied with regard to hydrogen pressure and storage temperature, as well as with regard to electrode manufacturing processes. Impedance characteristics were monitored and found to be indicative of electrode manufacturing processes and capacity loss. Cell testing to evaluate state-of-charge effects on capacity loss were inconclusive as no loss was sustained by the cells tested in this experiment.

  18. Nickel-hydrogen capacity loss on storage

    NASA Technical Reports Server (NTRS)

    Manzo, Michelle A.

    1989-01-01

    A controlled experiment evaluating the capacity loss experienced by nickel electrodes stored under various conditions of temperature, hydrogen pressure, and electrolyte concentration was conducted using nickel electrodes from four different manufacturers. It was found that capacity loss varied with respect to hydrogen pressure, and storage temperature as well as with respect to electrode manufacturing processes. Impedance characteristics were monitored and found to be indicative of electrode manufacturing processes and capacity loss. Cell testing to evaluate state-of-charge effects on capacity loss were inconclusive as no loss was sustained by the cells tested in this experiment.

  19. Hydrogen Storage in Metal-Organic Frameworks

    SciTech Connect

    Long, Jeffrey R.

    2016-04-28

    The design and characterization of new materials for hydrogen storage is an important area of research, as the ability to store hydrogen at lower pressures and higher temperatures than currently feasible would lower operating costs for small hydrogen fuel cell vehicles. In particular, metal-organic frameworks (MOFs) represent promising materials for use in storing hydrogen in this capacity. MOFs are highly porous, three-dimensional crystalline solids that are formed via linkages between metal ions (e.g., iron, nickel, and zinc) and organic molecules. MOFs can store hydrogen via strong adsorptive interactions between the gas molecules and the pores of the framework, providing a high surface area for gas adsorption and thus the opportunity to store hydrogen at significantly lower pressures than with current technologies. By lowering the energy required for hydrogen storage, these materials hold promise in rendering hydrogen a more viable fuel for motor vehicles, which is a highly desirable outcome given the clean nature of hydrogen fuel cells (water is the only byproduct of combustion) and the current state of global climate change resulting from the combustion of fossil fuels. The work presented in this report is the result of collaborative efforts between researchers at Lawrence Berkeley National Lab (LBNL), the National Institute of Standards and Technology (NIST), and General Motors Corporation (GM) to discover novel MOFs promising for H2 storage and characterize their properties. Described herein are several new framework systems with improved gravimetric and volumetric capacity to strongly bind H2 at temperatures relevant for vehicle storage. These materials were rigorously characterized using neutron diffraction, to determine the precise binding locations of hydrogen within the frameworks, and high-pressure H2 adsorption measurements, to provide a comprehensive picture of H2 adsorption at all relevant pressures. A

  20. Computational methods to determine the structure of hydrogen storage materials

    NASA Astrophysics Data System (ADS)

    Mueller, Tim

    2009-03-01

    To understand the mechanisms and thermodynamics of material-based hydrogen storage, it is important to know the structure of the material and the positions of the hydrogen atoms within the material. Because hydrogen can be difficult to resolve experimentally computational research has proven to be a valuable tool to address these problems. We discuss different computational methods for identifying the structure of hydrogen materials and the positions of hydrogen atoms, and we illustrate the methods with specific examples. Through the use of ab-initio molecular dynamics, we identify molecular hydrogen binding sites in the metal-organic framework commonly known as MOF-5 [1]. We present a method to identify the positions of atomic hydrogen in imide structures using a novel type of effective Hamiltonian. We apply this new method to lithium imide (Li2NH), a potentially important hydrogen storage material, and demonstrate that it predicts a new ground state structure [2]. We also present the results of a recent computational study of the room-temperature structure of lithium imide in which we suggest a new structure that reconciles the differences between previous experimental and theoretical studies. [4pt] [1] T. Mueller and G. Ceder, Journal of Physical Chemistry B 109, 17974 (2005). [0pt] [2] T. Mueller and G. Ceder, Physical Review B 74 (2006).

  1. Hydrogen storage and generation using light metal hydrides

    SciTech Connect

    Lynch, F.; Mork, B.J.; Wilkes, J.S.

    1998-07-01

    The storage of hydrogen for use in fuel cells employed as portable electric power sources is important. For many applications pressurized gas or cryogenic liquid storage is not acceptable from weight or safety standpoints. This is particularly true for moderate power systems in the 50--200 watt range. A potentially attractive technology for providing hydrogen for moderately sized fuel cell-based electric power supplies is chemical hydrides. In general, chemical hydrides are materials that store hydrogen that may be released by chemical reactions. The authors report here the use of light metal hydrides, such as lithium aluminum tetrahydride and trilithium aluminum hexahydride to store hydrogen in a very dense form; about four times the density of liquid hydrogen. The hydrogen can be released by reaction with simple chemical reagents, such as water or ammonia, at approximately atmospheric pressure and at modest temperatures. The reaction rate may be controlled to provide hydrogen at a rate appropriate to that needed by a fuel cell operating at the power levels mentioned above. Usually hydrogen is the sole gaseous product, along with several solid products.

  2. 20. DECOMMISIONED HYDROGEN TANK IN FORMER LIQUID OXYGEN STORAGE AREA, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    20. DECOMMISIONED HYDROGEN TANK IN FORMER LIQUID OXYGEN STORAGE AREA, BETWEEN TEST STAND 1-A AND INSTRUMENTATION AND CONTROL BUILDING. Looking northwest. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  3. Hydrogen-storage materials for mobile applications

    NASA Astrophysics Data System (ADS)

    Schlapbach, Louis; Züttel, Andreas

    2001-11-01

    Mobility - the transport of people and goods - is a socioeconomic reality that will surely increase in the coming years. It should be safe, economic and reasonably clean. Little energy needs to be expended to overcome potential energy changes, but a great deal is lost through friction (for cars about 10 kWh per 100 km) and low-efficiency energy conversion. Vehicles can be run either by connecting them to a continuous supply of energy or by storing energy on board. Hydrogen would be ideal as a synthetic fuel because it is lightweight, highly abundant and its oxidation product (water) is environmentally benign, but storage remains a problem. Here we present recent developments in the search for innovative materials with high hydrogen-storage capacity.

  4. Hydrogen-storage materials for mobile applications.

    PubMed

    Schlapbach, L; Züttel, A

    2001-11-15

    Mobility--the transport of people and goods - is a socioeconomic reality that will surely increase in the coming years. It should be safe, economic and reasonably clean. Little energy needs to be expended to overcome potential energy changes, but a great deal is lost through friction (for cars about 10 kWh per 100 km) and low-efficiency energy conversion. Vehicles can be run either by connecting them to a continuous supply of energy or by storing energy on board. Hydrogen would be ideal as a synthetic fuel because it is lightweight, highly abundant and its oxidation product (water) is environmentally benign, but storage remains a problem. Here we present recent developments in the search for innovative materials with high hydrogen-storage capacity.

  5. MODIFIED BOROHYDRIDES FOR REVERSIBLE HYDROGEN STORAGE

    SciTech Connect

    Au, Ming

    2006-05-10

    This paper reports the results in the effort to destabilize lithium borohydride for reversible hydrogen storage. A number of metals, metal hydrides, metal chlorides and complex hydrides were selected and evaluated as the destabilization agents for reducing dehydriding temperature and generating dehydriding-rehydriding reversibility. It is found that some additives are effective. The Raman spectroscopic analysis shows the change of B-H binding nature.

  6. ALUMINUM HYDRIDE: A REVERSIBLE MATERIAL FOR HYDROGEN STORAGE

    SciTech Connect

    Zidan, R; Christopher Fewox, C; Brenda Garcia-Diaz, B; Joshua Gray, J

    2009-01-09

    Hydrogen storage is one of the challenges to be overcome for implementing the ever sought hydrogen economy. Here we report a novel cycle to reversibly form high density hydrogen storage materials such as aluminium hydride. Aluminium hydride (AlH{sub 3}, alane) has a hydrogen storage capacity of 10.1 wt% H{sub 2}, 149 kg H{sub 2}/m{sup 3} volumetric density and can be discharged at low temperatures (< 100 C). However, alane has been precluded from use in hydrogen storage systems because of the lack of practical regeneration methods. The direct hydrogenation of aluminium to form AlH{sub 3} requires over 10{sup 5} bars of hydrogen pressure at room temperature and there are no cost effective synthetic means. Here we show an unprecedented reversible cycle to form alane electrochemically, using alkali metal alanates (e.g. NaAlH{sub 4}, LiAlH{sub 4}) in aprotic solvents. To complete the cycle, the starting alanates can be regenerated by direct hydrogenation of the dehydrided alane and the alkali hydride being the other compound formed in the electrochemical cell. The process of forming NaAlH{sub 4} from NaH and Al is well established in both solid state and solution reactions. The use of adducting Lewis bases is an essential part of this cycle, in the isolation of alane from the mixtures of the electrochemical cell. Alane is isolated as the triethylamine (TEA) adduct and converted to pure, unsolvated alane by heating under vacuum.

  7. ALUMINUM HYDRIDE: A REVERSIBLE MATERIAL FOR HYDROGEN STORAGE

    SciTech Connect

    Fewox, C; Ragaiy Zidan, R; Brenda Garcia-Diaz, B

    2008-12-31

    Hydrogen storage is one of the greatest challenges for implementing the ever sought hydrogen economy. Here we report a novel cycle to reversibly form high density hydrogen storage materials such as aluminium hydride. Aluminium hydride (AlH{sub 3}, alane) has a hydrogen storage capacity of 10.1 wt% H{sub 2}, 149 kg H{sub 2}/m{sup 3} volumetric density and can be discharged at low temperatures (< 100 C). However, alane has been precluded from use in hydrogen storage systems because of the lack of practical regeneration methods; the direct hydrogenation of aluminium to form AlH{sub 3} requires over 10{sup 5} bars of hydrogen pressure at room temperature and there are no cost effective synthetic means. Here we show an unprecedented reversible cycle to form alane electrochemically, using alkali alanates (e.g. NaAlH{sub 4}, LiAlH{sub 4}) in aprotic solvents. To complete the cycle, the starting alanates can be regenerated by direct hydrogenation of the dehydrided alane and the alkali hydride being the other compound formed in the electrochemical cell. The process of forming NaAlH{sub 4} from NaH and Al is well established in both solid state and solution reactions. The use of adducting Lewis bases is an essential part of this cycle, in the isolation of alane from the mixtures of the electrochemical cell. Alane is isolated as the triethylamine (TEA) adduct and converted to pure, unsolvated alane by heating under vacuum.

  8. Final Report: Hydrogen Storage System Cost Analysis

    SciTech Connect

    James, Brian David; Houchins, Cassidy; Huya-Kouadio, Jennie Moton; DeSantis, Daniel A.

    2016-09-30

    The Fuel Cell Technologies Office (FCTO) has identified hydrogen storage as a key enabling technology for advancing hydrogen and fuel cell power technologies in transportation, stationary, and portable applications. Consequently, FCTO has established targets to chart the progress of developing and demonstrating viable hydrogen storage technologies for transportation and stationary applications. This cost assessment project supports the overall FCTO goals by identifying the current technology system components, performance levels, and manufacturing/assembly techniques most likely to lead to the lowest system storage cost. Furthermore, the project forecasts the cost of these systems at a variety of annual manufacturing rates to allow comparison to the overall 2017 and “Ultimate” DOE cost targets. The cost breakdown of the system components and manufacturing steps can then be used to guide future research and development (R&D) decisions. The project was led by Strategic Analysis Inc. (SA) and aided by Rajesh Ahluwalia and Thanh Hua from Argonne National Laboratory (ANL) and Lin Simpson at the National Renewable Energy Laboratory (NREL). Since SA coordinated the project activities of all three organizations, this report includes a technical description of all project activity. This report represents a summary of contract activities and findings under SA’s five year contract to the US Department of Energy (Award No. DE-EE0005253) and constitutes the “Final Scientific Report” deliverable. Project publications and presentations are listed in the Appendix.

  9. A multifaceted approach to hydrogen storage.

    PubMed

    Churchard, Andrew J; Banach, Ewa; Borgschulte, Andreas; Caputo, Riccarda; Chen, Jian-Cheng; Clary, David; Fijalkowski, Karol J; Geerlings, Hans; Genova, Radostina V; Grochala, Wojciech; Jaroń, Tomasz; Juanes-Marcos, Juan Carlos; Kasemo, Bengt; Kroes, Geert-Jan; Ljubić, Ivan; Naujoks, Nicola; Nørskov, Jens K; Olsen, Roar A; Pendolino, Flavio; Remhof, Arndt; Románszki, Loránd; Tekin, Adem; Vegge, Tejs; Zäch, Michael; Züttel, Andreas

    2011-10-14

    The widespread adoption of hydrogen as an energy carrier could bring significant benefits, but only if a number of currently intractable problems can be overcome. Not the least of these is the problem of storage, particularly when aimed at use onboard light-vehicles. The aim of this overview is to look in depth at a number of areas linked by the recently concluded HYDROGEN research network, representing an intentionally multi-faceted selection with the goal of advancing the field on a number of fronts simultaneously. For the general reader we provide a concise outline of the main approaches to storing hydrogen before moving on to detailed reviews of recent research in the solid chemical storage of hydrogen, and so provide an entry point for the interested reader on these diverse topics. The subjects covered include: the mechanisms of Ti catalysis in alanates; the kinetics of the borohydrides and the resulting limitations; novel transition metal catalysts for use with complex hydrides; less common borohydrides; protic-hydridic stores; metal ammines and novel approaches to nano-confined metal hydrides.

  10. DFT investigations of hydrogen storage materials

    NASA Astrophysics Data System (ADS)

    Wang, Gang

    Hydrogen serves as a promising new energy source having no pollution and abundant on earth. However the most difficult problem of applying hydrogen is to store it effectively and safely, which is smartly resolved by attempting to keep hydrogen in some metal hydrides to reach a high hydrogen density in a safe way. There are several promising metal hydrides, the thermodynamic and chemical properties of which are to be investigated in this dissertation. Sodium alanate (NaAlH4) is one of the promising metal hydrides with high hydrogen storage capacity around 7.4 wt. % and relatively low decomposition temperature of around 100 °C with proper catalyst. Sodium hydride is a product of the decomposition of NaAlH4 that may affect the dynamics of NaAlH4. The two materials with oxygen contamination such as OH- may influence the kinetics of the dehydriding/rehydriding processes. Thus the solid solubility of OH - groups (NaOH) in NaAlH4 and NaH is studied theoretically by DFT calculations. Magnesium boride [Mg(BH4)2] is has higher hydrogen capacity about 14.9 wt. % and the decomposition temparture of around 250 °C. However one flaw restraining its application is that some polyboron compounds like MgB12H12 preventing from further release of hydrogen. Adding some transition metals that form magnesium transition metal ternary borohydride [MgaTMb(BH4)c] may simply the decomposition process to release hydrogen with ternary borides (MgaTMbBc). The search for the probable ternary borides and the corresponding pseudo phase diagrams as well as the decomposition thermodynamics are performed using DFT calculations and GCLP method to present some possible candidates.

  11. Hydrogen Storage Characteristics of Nanocrystalline and Amorphous Nd-Mg-Ni-Based NdMg12-Type Alloys Synthesized via Mechanical Milling

    NASA Astrophysics Data System (ADS)

    Zhang, Yanghuan; Shang, Hongwei; Hou, Zhonghui; Yuan, Zeming; Yang, Tai; Qi, Yan

    2016-12-01

    In this study, Mg was partially substituted by Ni with the intent of improving the hydrogen storage kinetics performance of NdMg12-type alloy. Mechanical milling technology was adopted to fabricate the nanocrystalline and amorphous NdMg11Ni + x wt pct Ni ( x = 100, 200) alloys. The effects of Ni content and milling duration on the microstructures and hydrogen storage kinetics of as-milled alloys have been systematically investigated. The structures were characterized by XRD and HRTEM. The electrochemical hydrogen storage properties were tested by an automatic galvanostatic system. Moreover, the gaseous hydrogen storage properties were investigated by Sievert apparatus and a differential scanning calorimeter connected with a H2 detector. Hydrogen desorption activation energy of alloy hydrides was estimated by using Arrhenius and Kissinger methods. The results reveal that the increase of Ni content dramatically ameliorates the gaseous and electrochemical hydrogen storage kinetics performance of the as-milled alloys. Furthermore, high rate discharge ability (HRD) reach the maximum value with the variation of milling time. The maximum HRDs of the NdMg11Ni + x wt pct Ni ( x = 100, 200) alloys are 80.24 and 85.17 pct. The improved gaseous hydrogen storage kinetics of alloys via increasing Ni content and milling time can be attributed to a decrease in the hydrogen desorption activation energy.

  12. Hydrogen storage by physisorption on Metal Organic Frameworks

    NASA Astrophysics Data System (ADS)

    Dailly, Anne

    2008-03-01

    Cryo-adsorption systems based on materials with high specific surface areas have the main advantage that they can store and release hydrogen with fast kinetics and high reversibility over multiples cycles. Recently Metal Organic Frameworks (MOFs) have been proposed as promising adsorbents for hydrogen. These crystallographically well organized hybrid solids resulting from the three dimensional connection of inorganic clusters using organic linkers show the largest specific surface areas of all known crystalline solids. The determination of the relationships between physical properties (chemistry, structure, surface area ) of the MOFs and their hydrogen storage behavior is a key step in the characterization of these materials, if they are to be designed for hydrogen storage applications. Excess hydrogen sorption measurements for different MOFs will be presented. We show that maximum hydrogen uptake at high pressure and 77K does not always scale with the specific surface area. A linear correlation trend only apply within a class of specific materials and breaks down when the surface area measurement does not represent the surface sites that are available to H2. The influence of pore size and shape will also be discussed by comparing several MOFs with different structure types. The hydrogen adsorption and binding energy at low pressure are strongly dependent on the metal ions and the pore size.

  13. Ford/BASF/UM Activities in Support of the Hydrogen Storage Engineering Center of Excellence

    SciTech Connect

    Veenstra, Mike; Purewal, Justin; Xu, Chunchuan; Yang, Jun; Blaser, Rachel; Sudik, Andrea; Siegel, Don; Ming, Yang; Liu, Dong'an; Chi, Hang; Gaab, Manuela; Arnold, Lena; Muller, Ulrich

    2015-06-30

    Widespread adoption of hydrogen as a vehicular fuel depends critically on the development of low-cost, on-board hydrogen storage technologies capable of achieving high energy densities and fast kinetics for hydrogen uptake and release. As present-day technologies -- which rely on physical storage methods such as compressed hydrogen -- are incapable of attaining established Department of Energy (DOE) targets, development of materials-based approaches for storing hydrogen have garnered increasing attention. Material-based storage technologies have potential to store hydrogen beyond twice the density of liquid hydrogen. To hasten development of these ‘hydride’ materials, the DOE previously established three centers of excellence for materials storage R&D associated with the key classes of materials: metal hydrides, chemical hydrogen, and adsorbents. While these centers made progress in identifying new storage materials, the challenges associated with the engineering of the system around a candidate storage material are in need of further advancement. In 2009 the DOE established the Hydrogen Storage Engineering Center of Excellence with the objective of developing innovative engineering concepts for materials-based hydrogen storage systems. As a partner in the Hydrogen Storage Engineering Center of Excellence, the Ford-UM-BASF team conducted a multi-faceted research program that addresses key engineering challenges associated with the development of materials-based hydrogen storage systems. First, we developed a novel framework that allowed for a material-based hydrogen storage system to be modeled and operated within a virtual fuel cell vehicle. This effort resulted in the ability to assess dynamic operating parameters and interactions between the storage system and fuel cell power plant, including the evaluation of performance throughout various drive cycles. Second, we engaged in cost modeling of various incarnations of the storage systems. This analysis

  14. Microstructure-Property Correlation in Magnesium-based Hydrogen Storage Systems: The Case for Ball-milled Magnesium Hydride Powder and Magnesium-based Multilayered Composites

    NASA Astrophysics Data System (ADS)

    Danaie, Mohsen

    The main focus of this thesis is the characterization of defects and microstructure in high-energy ball milled magnesium hydride powder and magnesium-based multilayered composites. Enhancement in kinetics of hydrogen cycling in magnesium can be achieved by applying severe plastic deformation. A literature survey reveals that, due to extreme instability of alpha-MgH 2 in transmission electron microscope (TEM), the physical parameters that researchers have studied are limited to particle size and grain size. By utilizing a cryogenic TEM sample holder, we extended the stability time of the hydride phase during TEM characterization. Milling for only 30 minutes resulted in a significant enhancement in desorption kinetics. A subsequent annealing cycle under pressurized hydrogen reverted the kinetics to its initial sluggish state. Cryo-TEM analysis of the milled hydride revealed that mechanical milling induces deformation twinning in the hydride microstructure. Milling did not alter the thermodynamics of desorption. Twins can enhance the kinetics by acting as preferential locations for the heterogeneous nucleation of metallic magnesium. We also looked at the phase transformation characteristics of desorption in MgH2. By using energy-filtered TEM, we investigated the morphology of the phases in a partially desorbed state. Our observations prove that desorption phase transformation in MgH2 is of "nucleation and growth" type, with a substantial energy barrier for nucleation. This is contrary to the generally assumed "core-shell" structure in most of the simulation models for this system. We also tested the hydrogen storage cycling behavior of bulk centimeter-scale Mg-Ti and Mg-SS multilayer composites synthesized by accumulative roll-bonding. Addition of either phase (Ti or SS) allows the reversible hydrogen sorption at 350°C, whereas identically roll-bonded pure magnesium cannot be absorbed. In the composites the first cycle of absorption (also called "activation

  15. Feasibility and induced effects of subsurface porous media hydrogen storage

    NASA Astrophysics Data System (ADS)

    Tilmann Pfeiffer, Wolf; Li, Dedong; Wang, Bo; Bauer, Sebastian

    2015-04-01

    Fluctuations in energy production from renewable sources like wind or solar power can lead to shortages in energy supply which can be mitigated using energy storage concepts. Underground storage of hydrogen in porous sandstone formations could be a storage option for large amounts of energy over long storage cycles. However, this use of the subsurface requires an analysis of possible interactions with other uses of the subsurface such as geothermal energy storage or groundwater abstraction. This study aims at quantifying the feasibility of porous media hydrogen storage to provide stored energy on a timescale of several days to weeks as well as possible impacts on the subsurface. The hypothetical storage site is based on an anticlinal structure located in Schleswig-Holstein, northern Germany. The storage is injected and extracted using five wells completed in a partially eroded, heterogeneous sandstone layer in the top of the structure at a depth of about 500 m. The storage formation was parameterized based on a local facies model with intrinsic permeabilities of 250-2500 mD and porosities of 35-40%. Storage initialization and subsequent storage cycles, each consisting of a hydrogen injection and extraction, were numerically simulated. The simulation results indicate the general feasibility of this hydrogen storage concept. The simulated sandstone formation is able to provide an average of around 1480 t of hydrogen per week (1830 TJ) which is about 5% of the total weekly energy production or about 10% of the weekly energy consumption of Schleswig-Holstein with the hydrogen production rate being the limiting factor of the overall performance. Induced hydraulic effects are a result of the induced overpressure within the storage formation. Propagation of the pressure signal does not strongly depend on the formation heterogeneity and thus shows approximately radial characteristics with one bar pressure change in distances of about 5 km from the injection wells. Thermal

  16. Microporous Metal Organic Materials for Hydrogen Storage

    SciTech Connect

    S. G. Sankar; Jing Li; Karl Johnson

    2008-11-30

    We have examined a number of Metal Organic Framework Materials for their potential in hydrogen storage applications. Results obtained in this study may, in general, be summarized as follows: (1) We have identified a new family of porous metal organic framework materials with the compositions M (bdc) (ted){sub 0.5}, {l_brace}M = Zn or Co, bdc = biphenyl dicarboxylate and ted = triethylene diamine{r_brace} that adsorb large quantities of hydrogen ({approx}4.6 wt%) at 77 K and a hydrogen pressure of 50 atm. The modeling performed on these materials agree reasonably well with the experimental results. (2) In some instances, such as in Y{sub 2}(sdba){sub 3}, even though the modeling predicted the possibility of hydrogen adsorption (although only small quantities, {approx}1.2 wt%, 77 K, 50 atm. hydrogen), our experiments indicate that the sample does not adsorb any hydrogen. This may be related to the fact that the pores are extremely small or may be attributed to the lack of proper activation process. (3) Some samples such as Zn (tbip) (tbip = 5-tert butyl isophthalate) exhibit hysteresis characteristics in hydrogen sorption between adsorption and desorption runs. Modeling studies on this sample show good agreement with the desorption behavior. It is necessary to conduct additional studies to fully understand this behavior. (4) Molecular simulations have demonstrated the need to enhance the solid-fluid potential of interaction in order to achieve much higher adsorption amounts at room temperature. We speculate that this may be accomplished through incorporation of light transition metals, such as titanium and scandium, into the metal organic framework materials.

  17. Carbon nanotube materials for hydrogen storage

    SciTech Connect

    Dillon, A.C.; Parilla, P.A.; Jones, K.M.; Riker, G.; Heben, M.J.

    1998-08-01

    Carbon single-wall nanotubes (SWNTs) are essentially elongated pores of molecular dimensions and are capable of adsorbing hydrogen at relatively high temperatures and low pressures. This behavior is unique to these materials and indicates that SWNTs are the ideal building block for constructing safe, efficient, and high energy density adsorbents for hydrogen storage applications. In past work the authors developed methods for preparing and opening SWNTs, discovered the unique adsorption properties of these new materials, confirmed that hydrogen is stabilized by physical rather than chemical interactions, measured the strength of interaction to be {approximately} 5 times higher than for adsorption on planar graphite, and performed infrared absorption spectroscopy to determine the chemical nature of the surface terminations before, during, and after oxidation. This year the authors have made significant advances in synthesis and characterization of SWNT materials so that they can now prepare gram quantities of high-purity SWNT samples and measure and control the diameter distribution of the tubes by varying key parameters during synthesis. They have also developed methods which purify nanotubes and cut nanotubes into shorter segments. These capabilities provide a means for opening the tubes which were unreactive to the oxidation methods that successfully opened tubes, and offer a path towards organizing nanotube segments to enable high volumetric hydrogen storage densities. They also performed temperature programmed desorption spectroscopy on high purity carbon nanotube material obtained from collaborator Prof. Patrick Bernier and finished construction of a high precision Seivert`s apparatus which will allow the hydrogen pressure-temperature-composition phase diagrams to be evaluated for SWNT materials.

  18. Technoeconomic analysis of renewable hydrogen production, storage, and detection systems

    SciTech Connect

    Mann, M.K.; Spath, P.L.; Kadam, K.

    1996-10-01

    Technical and economic feasibility studies of different degrees of completeness and detail have been performed on several projects being funded by the Department of Energy`s Hydrogen Program. Work this year focused on projects at the National Renewable Energy Laboratory, although analyses of projects at other institutions are underway or planned. Highly detailed analyses were completed on a fiber optic hydrogen leak detector and a process to produce hydrogen from biomass via pyrolysis followed by steam reforming of the pyrolysis oil. Less detailed economic assessments of solar and biologically-based hydrogen production processes have been performed and focused on the steps that need to be taken to improve the competitive position of these technologies. Sensitivity analyses were conducted on all analyses to reveal the degree to which the cost results are affected by market changes and technological advances. For hydrogen storage by carbon nanotubes, a survey of the competing storage technologies was made in order to set a baseline for cost goals. A determination of the likelihood of commercialization was made for nearly all systems examined. Hydrogen from biomass via pyrolysis and steam reforming was found to have significant economic potential if a coproduct option could be co-commercialized. Photoelectrochemical hydrogen production may have economic potential, but only if low-cost cells can be modified to split water and to avoid surface oxidation. The use of bacteria to convert the carbon monoxide in biomass syngas to hydrogen was found to be slightly more expensive than the high end of currently commercial hydrogen, although there are significant opportunities to reduce costs. Finally, the cost of installing a fiber-optic chemochromic hydrogen detection system in passenger vehicles was found to be very low and competitive with alternative sensor systems.

  19. Thermal effects in dynamic storage of hydrogen by adsorption

    SciTech Connect

    Lamari, M.; Aoufi, A.; Malbrunot, P.

    2000-03-01

    Thermal effects in dynamic hydrogen storage by adsorption at room temperature and high pressure are studied theoretically and experimentally. The system of adsorbate-adsorbent used was hydrogen in granular activated carbon. The theoretical analysis was based on heat- and mass-transfer modeling in a packed-bed adsorber, with particular emphasis on the thermal effects occurring during charge and discharge steps. The influence of gas flow rate and storage pressure (up to 15 MPa) on the total amount stored or delivered was investigated. Operating conditions were compatible with practical application for onboard vehicle storage. The experimental study was carried out in cylindrical 2-L reservoirs filled with granular activated carbon in which the bed temperature was measured at various positions. The temperature changes during both charge and discharge agreed well with the model predictions.

  20. Nanodiamond for hydrogen storage: temperature-dependent hydrogenation and charge-induced dehydrogenation.

    PubMed

    Lai, Lin; Barnard, Amanda S

    2012-02-21

    Carbon-based hydrogen storage materials are one of hottest research topics in materials science. Although the majority of studies focus on highly porous loosely bound systems, these systems have various limitations including use at elevated temperature. Here we propose, based on computer simulations, that diamond nanoparticles may provide a new promising high temperature candidate with a moderate storage capacity, but good potential for recyclability. The hydrogenation of nanodiamonds is found to be easily achieved, in agreement with experiments, though we find the stability of hydrogenation is dependent on the morphology of nanodiamonds and surrounding environment. Hydrogenation is thermodynamically favourable even at high temperature in pure hydrogen, ammonia, and methane gas reservoirs, whereas water vapour can help to reduce the energy barrier for desorption. The greatest challenge in using this material is the breaking of the strong covalent C-H bonds, and we have identified that the spontaneous release of atomic hydrogen may be achieved through charging of hydrogenated nanodiamonds. If the degree of induced charge is properly controlled, the integrity of the host nanodiamond is maintained, which indicates that an efficient and recyclable approach for hydrogen release may be possible.

  1. [Raman spectroscopic investigation of hydrogen storage in nitrogen gas hydrates].

    PubMed

    Meng, Qing-guo; Liu, Chang-ling; Ye, Yu-guang; Li, Cheng-feng

    2012-08-01

    Recently, hydrogen storage using clathrate hydrate as a medium has become a hotspot of hydrogen storage research In the present paper, the laser Raman spectroscopy was used to study the hydrogen storage in nitrogen hydrate. The synthetic nitrogen hydrate was reacted with hydrogen gas under relatively mild conditions (e.g., 15 MPa, -18 degrees C). The Raman spectra of the reaction products show that the hydrogen molecules have enclathrated the cavities of the nitrogen hydrate, with multiple hydrogen cage occupancies in the clathrate cavities. The reaction time is an important factor affecting the hydrogen storage in nitrogen hydrate. The experimental results suggest that nitrogen hydrates are expected to be an effective media for hydrogen storage.

  2. Hydrogen Fire in a Storage Vessel

    NASA Technical Reports Server (NTRS)

    Hester, Zena M.

    2010-01-01

    On October 23, 2007, the operations team began a procedure to sample the Liquid Hydrogen (LH2) storage vessels ("tanks"), and associated transfer system. This procedure was being performed to determine the conditions within the system, and if necessary, to purge the system of any excess Gaseous Hydrogen (GH2) in preparation for reactivation of the system. The system had not been used since 2003. The LH2 storage system contains two (2) spherical pressure vessels of 225,000 gallons in volume, with a maximum working pressure (MAWP) of 50 psig. Eight inch transfer piping connects them to the usage point. Operations began with activation of the burnstack for the LH2 storage area. Pneumatic (GN2) systems in the storage area were then activated and checked. Pressurization of storage tank number 1 with gaseous nitrogen (GN2) was initiated, with a target pressure of 10 psig, at which point samples were planned to be taken. At 5 psig, a loud noise was heard in the upper area of tank number 2. Smoke was seen exiting the burnstack and from the insulation on vent lines for both tanks. At this time tank number 1 was vented and the pressurization system was secured. The mishap resulted in physical damage to both storage tanks, as well as to some of the piping for both tanks. Corrective action included repair of the damaged hardware by a qualified contractor. Preventive action included documented organizational policy and procedures for establishing standby and mothball conditions for facilities and equipment, including provisions as detailed in the investigation report recommendations: Recommendation 1: The using organization should define necessary activities in order to place hydrogen systems in long term periods of inactivity. The defined activities should address requirements for rendering inert, isolation (i.e., physical disconnect, double block and bleed, etc.) and periodic monitoring. Recommendation 2: The using organization should develop a process to periodically monitor

  3. Hydrogen storage in the form of metal hydrides

    NASA Technical Reports Server (NTRS)

    Zwanziger, M. G.; Santana, C. C.; Santos, S. C.

    1984-01-01

    Reversible reactions between hydrogen and such materials as iron/titanium and magnesium/ nickel alloy may provide a means for storing hydrogen fuel. A demonstration model of an iron/titanium hydride storage bed is described. Hydrogen from the hydride storage bed powers a converted gasoline electric generator.

  4. High-capacity hydrogen storage in lithium and sodium amidoboranes

    NASA Astrophysics Data System (ADS)

    Xiong, Zhitao; Yong, Chaw Keong; Wu, Guotao; Chen, Ping; Shaw, Wendy; Karkamkar, Abhi; Autrey, Thomas; Jones, Martin Owen; Johnson, Simon R.; Edwards, Peter P.; David, William I. F.

    2008-02-01

    The safe and efficient storage of hydrogen is widely recognized as one of the key technological challenges in the transition towards a hydrogen-based energy economy. Whereas hydrogen for transportation applications is currently stored using cryogenics or high pressure, there is substantial research and development activity in the use of novel condensed-phase hydride materials. However, the multiple-target criteria accepted as necessary for the successful implementation of such stores have not yet been met by any single material. Ammonia borane, NH3BH3, is one of a number of condensed-phase compounds that have received significant attention because of its reported release of ~12wt% hydrogen at moderate temperatures (~150° C). However, the hydrogen purity suffers from the release of trace quantities of borazine. Here, we report that the related alkali-metal amidoboranes, LiNH2BH3 and NaNH2BH3, release ~10.9wt% and ~7.5wt% hydrogen, respectively, at significantly lower temperatures (~90°C) with no borazine emission. The low-temperature release of a large amount of hydrogen is significant and provides the potential to fulfil many of the principal criteria required for an on-board hydrogen store.

  5. Understanding atomistic phenomenon for hydrogen storage in complex metal hydrides

    NASA Astrophysics Data System (ADS)

    Chopra, Irinder Singh

    transport is required. These results provide an understanding of the reaction mechanisms for hydrogen storage in the alanates (NaAlH4) that can help in identifying and realizing other complex metal hydrides for an effective hydrogen based economy.

  6. Mixed-linker approach in designing porous zirconium-based metal-organic frameworks with high hydrogen storage capacity.

    PubMed

    Naeem, Ayesha; Ting, Valeska P; Hintermair, Ulrich; Tian, Mi; Telford, Richard; Halim, Saaiba; Nowell, Harriott; Hołyńska, Małgorzata; Teat, Simon J; Scowen, Ian J; Nayak, Sanjit

    2016-06-14

    Three highly porous Zr(iv)-based metal-organic frameworks, UBMOF-8, UBMOF-9, and UBMOF-31, were synthesized by using 2,2'-diamino-4,4'-stilbenedicarboxylic acid, 4,4'-stilbenedicarboxylic acid, and combination of both linkers, respectively. The mixed-linker UBMOF-31 showed excellent hydrogen uptake of 4.9 wt% and high selectivity for adsorption of CO2 over N2 with high thermal stability and moderate water stability with permanent porosity and surface area of 2552 m(2) g(-1).

  7. Computational study of sodium magnesium hydride for hydrogen storage applications

    NASA Astrophysics Data System (ADS)

    Soto Valle, Fernando Antonio

    Hydrogen offers considerable potential benefits as an energy carrier. However, safe and convenient storage of hydrogen is one of the biggest challenges to be resolved in the near future. Sodium magnesium hydride (NaMgH 3) has attracted attention as a hydrogen storage material due to its light weight and high volumetric hydrogen density of 88 kg/m3. Despite the advantages, hydrogen release in this material occurs at approximately 670 K, which is well above the operable range for on-board hydrogen storage applications. In this regard, hydrogen release may be facilitated by substitution doping of transition-metals. This dissertation describes first-principles computational methods that enable an examination of the hydrogen storage properties of NaMgH3. The novel contribution of this dissertation includes a combination of crystal, supercell, and surface slab calculations that provides new and relevant insights about the thermodynamic and kinetic properties of NaMgH3. First-principles calculations on the pristine crystal structure provide a starting reference point for the study of this material as a hydrogen storage material. To the best of our knowledge, it is reported for the first time that a 25% mol doping concentration of Ti, V, Cu, and Zn dopants reduce the reaction enthalpy of hydrogen release for NaMgH3. The largest decrease in the DeltaH(298 K) value corresponds to the Zn-doped model (67.97 kJ/(mol H2)). Based on cohesive energy calculations, it is reported that at the 6.25% mol doping concentration, Ti and Zn dopants are the only transition metals that destabilize the NaMgH3 hydride. In terms of hydrogen removal energy, it is quantified that the energy cost to remove a single H from the Ti-doped supercell model is 0.76 eV, which is lower with respect to the pristine model and other prototypical hydrogen storage materials. From the calculation of electronic properties such as density of states, electron density difference, and charge population analysis

  8. Hydrogen Storage Performance in Pd/Graphene Nanocomposites.

    PubMed

    Zhou, Chunyu; Szpunar, Jerzy A

    2016-10-05

    We have developed a Pd-graphene nanocomposite for hydrogen storage. The spherically shaped Pd nanoparticles of 5-45 nm in size are homogeneously distributed over the graphene matrix. This new hydrogen storage system has favorable features like desirable hydrogen storage capacity, ambient conditions of hydrogen uptake, and low temperature of hydrogen release. At a hydrogen charging pressure of 50 bar, the material could yield a gravimetric density of 6.7 wt % in the 1% Pd/graphene nanocomposite. As we increased the applied pressure to 60 bar, the hydrogen uptake capacity reached 8.67 wt % in the 1% Pd/graphene nanocomposite and 7.16 wt % in the 5% Pd/graphene nanocomposite. This system allows storage of hydrogen in amounts that exceed the capacity of the gravimetric target announced by the U.S. Department of Energy (DOE).

  9. Chemical hydrogen storage material property guidelines for automotive applications

    NASA Astrophysics Data System (ADS)

    Semelsberger, Troy A.; Brooks, Kriston P.

    2015-04-01

    Chemical hydrogen storage is the sought after hydrogen storage media for automotive applications because of the expected low pressure operation (<20 atm), moderate temperature operation (<200 °C), system gravimetric capacities (>0.05 kg H2/kgsystem), and system volumetric capacities (>0.05 kg H2/Lsystem). Currently, the primary shortcomings of chemical hydrogen storage are regeneration efficiency, fuel cost and fuel phase (i.e., solid or slurry phase). Understanding the required material properties to meet the DOE Technical Targets for Onboard Hydrogen Storage Systems is a critical knowledge gap in the hydrogen storage research community. This study presents a set of fluid-phase chemical hydrogen storage material property guidelines for automotive applications meeting the 2017 DOE technical targets. Viable material properties were determined using a boiler-plate automotive system design. The fluid-phase chemical hydrogen storage media considered in this study were neat liquids, solutions, and non-settling homogeneous slurries. Material properties examined include kinetics, heats of reaction, fuel-cell impurities, gravimetric and volumetric hydrogen storage capacities, and regeneration efficiency. The material properties, although not exhaustive, are an essential first step in identifying viable chemical hydrogen storage material properties-and most important, their implications on system mass, system volume and system performance.

  10. Hydrogen storage materials and method of making by dry homogenation

    DOEpatents

    Jensen, Craig M.; Zidan, Ragaiy A.

    2002-01-01

    Dry homogenized metal hydrides, in particular aluminum hydride compounds, as a material for reversible hydrogen storage is provided. The reversible hydrogen storage material comprises a dry homogenized material having transition metal catalytic sites on a metal aluminum hydride compound, or mixtures of metal aluminum hydride compounds. A method of making such reversible hydrogen storage materials by dry doping is also provided and comprises the steps of dry homogenizing metal hydrides by mechanical mixing, such as be crushing or ball milling a powder, of a metal aluminum hydride with a transition metal catalyst. In another aspect of the invention, a method of powering a vehicle apparatus with the reversible hydrogen storage material is provided.

  11. Chemical hydrogen storage material property guidelines for automotive applications

    SciTech Connect

    Semelsberger, Troy; Brooks, Kriston P.

    2015-04-01

    Chemical hydrogen storage is the sought after hydrogen storage media for automotive applications because of the expected low pressure operation (<20 atm), moderate temperature operation (<200 C), system gravimetric capacities (>0.05 kg H2/kg system), and system volumetric capacities (>0.05 kg H2/L system). Currently, the primary shortcomings of chemical hydrogen storage are regeneration efficiency, fuel cost and fuel phase (i.e., solid or slurry phase). Understanding the required material properties to meet the DOE Technical Targets for Onboard Hydrogen Storage Systems is a critical knowledge gap in the hydrogen storage research community. This study presents a set of fluid-phase chemical hydrogen storage material property guidelines for automotive applications meeting the 2017 DOE technical targets. Viable material properties were determined using a boiler-plate automotive system design. The fluid phase chemical hydrogen storage media considered in this study were neat liquids, solutions, and non-settling homogeneous slurries. Material properties examined include kinetics, heats of reaction, fuel-cell impurities, gravimetric and volumetric hydrogen storage capacities, and regeneration efficiency. The material properties, although not exhaustive, are an essential first step in identifying viable chemical hydrogen storage material propertiesdand most important, their implications on system mass, system volume and system performance.

  12. Nanostructured polymeric materials for hydrogen storage

    SciTech Connect

    Liu, Di-Jia

    2013-03-01

    The objective of this project is to develop a new class of hydrogen storage adsorbent, nanostructured porous organic polymers (POPs), through collaboration between Argonne National Laboratory and The University of Chicago. POPs have excellent thermal stability and tolerance to gas contaminants such as moisture. They also have low skeleton density and high intrinsic porosity via covalent bonds, capable of maintaining specific surface area (SSA) during high pressure pelletizing for better volumetric density. Furthermore, they can be produced at a commercial scale with the existing industrial infrastructure. The team’s approach focused on improving hydrogen uptake capacity and the heat of adsorption by enhancing SSA, porosity control, and framework-adsorbate interactions through rational design and synthesis at the molecular level. The design principles aim at improving the following attributes of the polymers: (a) high SSA to provide sufficient interface with H2; (b) narrow pore diameter to enhance van der Waals interactions in the confined space; and (c) “metallic” features, either through π- conjugation or metal doping, to promote electronic orbital interactions with hydrogen.

  13. BIMETALLIC LITHIUM BOROHYDRIDES TOWARD REVERSIBLE HYDROGEN STORAGE

    SciTech Connect

    Au, M.

    2010-10-21

    Borohydrides such as LiBH{sub 4} have been studied as candidates for hydrogen storage because of their high hydrogen contents (18.4 wt% for LiBH{sub 4}). Limited success has been made in reducing the dehydrogenation temperature by adding reactants such as metals, metal oxides and metal halides. However, full rehydrogenation has not been realized because of multi-step decomposition processes and the stable intermediate species produced. It is suggested that adding second cation in LiBH{sub 4} may reduce the binding energy of B-H. The second cation may also provide the pathway for full rehydrogenation. In this work, several bimetallic borohydrides were synthesized using wet chemistry, high pressure reactive ball milling and sintering processes. The investigation found that the thermodynamic stability was reduced, but the full rehydrogenation is still a challenge. Although our experiments show the partial reversibility of the bimetallic borohydrides, it was not sustainable during dehydriding-rehydriding cycles because of the accumulation of hydrogen inert species.

  14. Process for synthesis of ammonia borane for bulk hydrogen storage

    DOEpatents

    Autrey, S Thomas [West Richland, WA; Heldebrant, David J [Richland, WA; Linehan, John C [Richland, WA; Karkamkar, Abhijeet J [Richland, WA; Zheng, Feng [Richland, WA

    2011-03-01

    The present invention discloses new methods for synthesizing ammonia borane (NH.sub.3BH.sub.3, or AB). Ammonium borohydride (NH.sub.4BH.sub.4) is formed from the reaction of borohydride salts and ammonium salts in liquid ammonia. Ammonium borohydride is decomposed in an ether-based solvent that yields AB at a near quantitative yield. The AB product shows promise as a chemical hydrogen storage material for fuel cell powered applications.

  15. Coupling of exothermic and endothermic hydrogen storage materials

    NASA Astrophysics Data System (ADS)

    Brooks, Kriston P.; Bowden, Mark E.; Karkamkar, Abhijeet J.; Houghton, Adrian Y.; Autrey, S. Thomas

    2016-08-01

    Chemical hydrogen storage (CHS) materials are a high-storage-density alternative to the gaseous compressed hydrogen currently used to provide hydrogen for fuel cell vehicles. One of the challenges of CHS materials is addressing the energy barriers required to break the chemical bonds and release the hydrogen. Coupling CHS reactions that are endothermic and exothermic during dehydrogenation can improve onboard energy efficiency and thermal control for the system, making such materials viable. Acceptable coupling between reactions requires both thermodynamic and kinetic considerations. In this work, models were developed to predict the reaction enthalpy and rate required to achieve high conversions for both reactions based on experimental measurements. Modeling results show that the coupling efficiency of exothermic and endothermic reactions is more sensitive to the ratio of the exothermic and endothermic enthalpies than to the ratio of the rates of the two steps. Modeling results also show that a slower endothermic step rate is desirable to permit sufficient heating of the reactor by the exothermic step. We look at two examples of a sequential and parallel reaction scheme and provide some of the first published insight into the required temperature range to maximize the hydrogen release from 1,2-BN cyclohexane and indoline.

  16. Low Cost, High Efficiency, High Pressure Hydrogen Storage

    SciTech Connect

    Mark Leavitt

    2010-03-31

    A technical and design evaluation was carried out to meet DOE hydrogen fuel targets for 2010. These targets consisted of a system gravimetric capacity of 2.0 kWh/kg, a system volumetric capacity of 1.5 kWh/L and a system cost of $4/kWh. In compressed hydrogen storage systems, the vast majority of the weight and volume is associated with the hydrogen storage tank. In order to meet gravimetric targets for compressed hydrogen tanks, 10,000 psi carbon resin composites were used to provide the high strength required as well as low weight. For the 10,000 psi tanks, carbon fiber is the largest portion of their cost. Quantum Technologies is a tier one hydrogen system supplier for automotive companies around the world. Over the course of the program Quantum focused on development of technology to allow the compressed hydrogen storage tank to meet DOE goals. At the start of the program in 2004 Quantum was supplying systems with a specific energy of 1.1-1.6 kWh/kg, a volumetric capacity of 1.3 kWh/L and a cost of $73/kWh. Based on the inequities between DOE targets and Quantum’s then current capabilities, focus was placed first on cost reduction and second on weight reduction. Both of these were to be accomplished without reduction of the fuel system’s performance or reliability. Three distinct areas were investigated; optimization of composite structures, development of “smart tanks” that could monitor health of tank thus allowing for lower design safety factor, and the development of “Cool Fuel” technology to allow higher density gas to be stored, thus allowing smaller/lower pressure tanks that would hold the required fuel supply. The second phase of the project deals with three additional distinct tasks focusing on composite structure optimization, liner optimization, and metal.

  17. Hydrogen storage in Chabazite zeolite frameworks.

    PubMed

    Regli, Laura; Zecchina, Adriano; Vitillo, Jenny G; Cocina, Donato; Spoto, Giuseppe; Lamberti, Carlo; Lillerud, Karl P; Olsbye, Unni; Bordiga, Silvia

    2005-09-07

    We have recently highlighted that H-SSZ-13, a highly siliceous zeolite (Si/Al = 11.6) with a chabazitic framework, is the most efficient zeolitic material for hydrogen storage [A. Zecchina, S. Bordiga, J. G. Vitillo, G. Ricchiardi, C. Lamberti, G. Spoto, M. Bjørgen and K. P. Lillerud, J. Am. Chem. Soc., 2005, 127, 6361]. The aim of this new study is thus to clarify both the role played by the acidic strength and by the density of the polarizing centers hosted in the same framework topology in the increase of the adsorptive capabilities of the chabazitic materials towards H2. To achieve this goal, the volumetric experiments of H2 uptake (performed at 77 K) and the transmission IR experiment of H2 adsorption at 15 K have been performed on H-SSZ-13, H-SAPO-34 (the isostructural silico-aluminophosphate material with the same Brønsted site density) and H-CHA (the standard chabazite zeolite: Si/Al = 2.1) materials. We have found that a H2 uptake improvement has been obtained by increasing the acidic strength of the Brønsted sites (moving from H-SAPO-34 to H-SSZ-13). Conversely, the important increase of the Brønsted sites density (moving from H-SSZ-13 to H-CHA) has played a negative role. This unexpected behavior has been explained as follows. The additional Brønsted sites are in mutual interaction via H-bonds inside the small cages of the chabazitic framework and for most of them the energetic cost needed to displace the adjacent OH ligand is higher than the adsorption enthalpy of the OH...H2 adduct. From our work it can be concluded that proton exchanged chabazitic frameworks represent, among zeolites, the most efficient materials for hydrogen storage. We have shown that a proper balance between available space (volume accessible to hydrogen), high contact surface, and specific interaction with strong and isolated polarizing centers are the necessary characteristics requested to design better materials for molecular H2 storage.

  18. Hydrogen Storage Engineering Center of Excellence Metal Hydride Final Report

    SciTech Connect

    Motyka, T.

    2014-05-31

    The Hydrogen Storage Engineering Center of Excellence (HSECoE) was established in 2009 by the U.S. Department of Energy (DOE) to advance the development of materials-based hydrogen storage systems for hydrogen-fueled light-duty vehicles. The overall objective of the HSECoE is to develop complete, integrated system concepts that utilize reversible metal hydrides, adsorbents, and chemical hydrogen storage materials through the use of advanced engineering concepts and designs that can simultaneously meet or exceed all the DOE targets. This report describes the activities and accomplishments during Phase 1 of the reversible metal hydride portion of the HSECoE, which lasted 30 months from February 2009 to August 2011. A complete list of all the HSECoE partners can be found later in this report but for the reversible metal hydride portion of the HSECoE work the major contributing organizations to this effort were the United Technology Research Center (UTRC), General Motors (GM), Pacific Northwest National Laboratory (PNNL), the National Renewable Energy Laboratory (NREL) and the Savannah River National Laboratory (SRNL). Specific individuals from these and other institutions that supported this effort and the writing of this report are included in the list of contributors and in the acknowledgement sections of this report. The efforts of the HSECoE are organized into three phases each approximately 2 years in duration. In Phase I, comprehensive system engineering analyses and assessments were made of the three classes of storage media that included development of system level transport and thermal models of alternative conceptual storage configurations to permit detailed comparisons against the DOE performance targets for light-duty vehicles. Phase 1 tasks also included identification and technical justifications for candidate storage media and configurations that should be capable of reaching or exceeding the DOE targets. Phase 2 involved bench-level testing and

  19. Hydrogen Peroxide Storage in Small Sealed Tanks

    SciTech Connect

    Whitehead, J.

    1999-10-20

    Unstabilized hydrogen peroxide of 85% concentration has been prepared in laboratory quantities for testing material compatibility and long term storage on a small scale. Vessels made of candidate tank and liner materials ranged in volume from 1 cc to 2540 cc. Numerous metals and plastics were tried at the smallest scales, while promising ones were used to fabricate larger vessels and liners. An aluminum alloy (6061-T6) performed poorly, including increasing homogeneous decay due to alloying elements entering solution. The decay rate in this high strength aluminum was greatly reduced by anodizing. Better results were obtained with polymers, particularly polyvinylidene fluoride. Data reported herein include ullage pressures as a function of time with changing decay rates, and contamination analysis results.

  20. Light metal hydrides and complex hydrides for hydrogen storage.

    PubMed

    Schüth, F; Bogdanović, B; Felderhoff, M

    2004-10-21

    The availability of feasible methods for hydrogen storage is one of the key-maybe the key-requirements for the large scale application of PEM fuel cells in cars. There are in principle four different approaches, i.e. cryostorage in liquid form, high pressure storage, storage in the form of a chemical compound which is converted to hydrogen by on-board reforming, or reversible chemical storage in different kinds of storage materials. New developments in the field of chemical storage make such systems attractive compared to the other options. This review will discuss the different possibilities for chemical storage of hydrogen and the focus on the presently most advanced system with respect to storage capacity and kinetics, i.e. catalyzed alanates, especially NaAlH(4).

  1. New perspectives on potential hydrogen storage materials using high pressure.

    PubMed

    Song, Yang

    2013-09-21

    In addressing the global demand for clean and renewable energy, hydrogen stands out as the most suitable candidate for many fuel applications that require practical and efficient storage of hydrogen. Supplementary to the traditional hydrogen storage methods and materials, the high-pressure technique has emerged as a novel and unique approach to developing new potential hydrogen storage materials. Static compression of materials may result in significant changes in the structures, properties and performance that are important for hydrogen storage applications, and often lead to the formation of unprecedented phases or complexes that have profound implications for hydrogen storage. In this perspective article, 22 types of representative potential hydrogen storage materials that belong to four major classes--simple hydride, complex hydride, chemical hydride and hydrogen containing materials--were reviewed. In particular, their structures, stabilities, and pressure-induced transformations, which were reported in recent experimental works together with supporting theoretical studies, were provided. The important contextual aspects pertinent to hydrogen storage associated with novel structures and transitions were discussed. Finally, the summary of the recent advances reviewed and the insight into the future research in this direction were given.

  2. Efficient hydrogen storage with the combination of lightweight Mg/MgH2 and nanostructures.

    PubMed

    Cheng, Fangyi; Tao, Zhanliang; Liang, Jing; Chen, Jun

    2012-07-28

    Efficient hydrogen storage plays a key role in realizing the incoming hydrogen economy. However, it still remains a great challenge to develop hydrogen storage media with high capacity, favourable thermodynamics, fast kinetics, controllable reversibility, long cycle life, low cost and high safety. To achieve this goal, the combination of lightweight materials and nanostructures should offer great opportunities. In this article, we review recent advances in the field of chemical hydrogen storage that couples lightweight materials and nanostructures, focusing on Mg/MgH(2)-based systems. Selective theoretical and experimental studies on Mg/MgH(2) nanostructures are overviewed, with the emphasis on illustrating the influences of nanostructures on the hydrogenation/dehydrogenation mechanisms and hydrogen storage properties such as capacity, thermodynamics and kinetics. In particular, theoretical studies have shown that the thermodynamics of Mg/MgH(2) clusters below 2 nm change more prominently as particle size decreases.

  3. Storage and transportation of merchant hydrogen

    NASA Astrophysics Data System (ADS)

    Eklund, G.; von Krusenstierna, O.

    Merchant hydrogen, that produced at one site and transported to another for a variety of end uses, will be produced from sources that depend on the demand area. Applications are mainly in the chemical and metallurgical industries, and total consumption is currently 0.5 Mtons/yr. Delivery is normally done with H2 in compressed form in steel cylinders with a 50 l capacity at 200 bar. Tube trailers as the delivery method have the disadvantage of taking the trailer tube from use during discharge, but some costs could be reduced by having aluminum cylinders. A problem would still persist in the necessity for providing insulation against evaporation, which could cause a loss of 30-70 percent of stored H2. The H2 could be stored in glass microspheres at high temperatures, then released for use by heating the spheres to 200 C. Storage is also possible with encapsulation in zeolites, cryoadsorption in carbon, chemical binding, and in hydrides. It is concluded that although transport in lightweight cylinders is feasible, no preferred storage method has yet been identified.

  4. Chemical Hydrides for Hydrogen Storage in Fuel Cell Applications

    SciTech Connect

    Devarakonda, Maruthi N.; Brooks, Kriston P.; Ronnebro, Ewa; Rassat, Scot D.; Holladay, Jamelyn D.

    2012-04-16

    Due to its high hydrogen storage capacity (up to 19.6% by weight for the release of 2.5 molar equivalents of hydrogen gas) and its stability under typical ambient conditions, ammonia borane (AB) is a promising material for chemical hydrogen storage for fuel cell applications in transportation sector. Several systems models for chemical hydride materials such as solid AB, liquid AB and alane were developed and evaluated at PNNL to determine an optimal configuration that would meet the 2010 and future DOE targets for hydrogen storage. This paper presents an overview of those systems models and discusses the simulation results for various transient drive cycle scenarios.

  5. Cloning single wall carbon nanotubes for hydrogen storage

    SciTech Connect

    Tour, James M; Kittrell, Carter

    2012-08-30

    The purpose of this research is to development the technology required for producing 3-D nano-engineered frameworks for hydrogen storage based on sp2 carbon media, which will have high gravimetric and especially high volumetric uptake of hydrogen, and in an aligned fibrous array that will take advantage of the exceptionally high thermal conductivity of sp2 carbon materials to speed up the fueling process while minimizing or eliminating the need for internal cooling systems. A limitation for nearly all storage media using physisorption of the hydrogen molecule is the large amount of surface area (SA) occupied by each H2 molecule due to its large zero-point vibrational energy. This creates a conundrum that in order to maximize SA, the physisorption media is made more tenuous and the density is decreased, usually well below 1 kg/L, so that there comes a tradeoff between volumetric and gravimetric uptake. Our major goal was to develop a new type of media with high density H2 uptake, which favors volumetric storage and which, in turn, has the capability to meet the ultimate DoE H2 goals.

  6. Durability study of a vehicle-scale hydrogen storage system.

    SciTech Connect

    Johnson, Terry Alan; Dedrick, Daniel E.; Behrens, Richard, Jr.

    2010-11-01

    Sandia National Laboratories has developed a vehicle-scale demonstration hydrogen storage system as part of a Work for Others project funded by General Motors. This Demonstration System was developed based on the properties and characteristics of sodium alanates which are complex metal hydrides. The technology resulting from this program was developed to enable heat and mass management during refueling and hydrogen delivery to an automotive system. During this program the Demonstration System was subjected to repeated hydriding and dehydriding cycles to enable comparison of the vehicle-scale system performance to small-scale sample data. This paper describes the experimental results of life-cycle studies of the Demonstration System. Two of the four hydrogen storage modules of the Demonstration System were used for this study. A well-controlled and repeatable sorption cycle was defined for the repeated cycling, which began after the system had already been cycled forty-one times. After the first nine repeated cycles, a significant hydrogen storage capacity loss was observed. It was suspected that the sodium alanates had been affected either morphologically or by contamination. The mechanisms leading to this initial degradation were investigated and results indicated that water and/or air contamination of the hydrogen supply may have lead to oxidation of the hydride and possibly kinetic deactivation. Subsequent cycles showed continued capacity loss indicating that the mechanism of degradation was gradual and transport or kinetically limited. A materials analysis was then conducted using established methods including treatment with carbon dioxide to react with sodium oxides that may have formed. The module tubes were sectioned to examine chemical composition and morphology as a function of axial position. The results will be discussed.

  7. Coupling of exothermic and endothermic hydrogen storage materials

    SciTech Connect

    Brooks, Kriston P.; Bowden, Mark E.; Karkamkar, Abhijeet J.; Houghton, Adrian Y.; Autrey, S. Thomas

    2016-08-01

    Chemical hydrogen storage (CHS) materials are a high-storage-density alternative to the gaseous compressed hydrogen currently used to provide hydrogen for fuel cell vehicles. One of the challenges of CHS materials is addressing the thermodynamic and kinetic barriers required to break the chemical bonds and release the hydrogen. Coupling CHS reactions that are endothermic and exothermic during the dehydrogenation can improve the system on-board energy efficiency and thermal control, making such materials viable. Acceptable coupling between reactions requires both thermodynamic and kinetics considerations. Models were developed to predict the reaction enthalpy and rate required to achieve high conversions for both reactions based on experimental measurements. These modeling results show that the efficiency of coupling of an exothermic and endothermic reaction is more sensitive the magnitude of the ratio of the exothermic and endothermic enthalpies than the ratio of the rates of the two steps. The modeling shows further that a slower rate of the endothermic step is desirable to permit sufficient heating of the reactor by the exothermic step. We look at two examples of a sequential and parallel reaction scheme and provide some of the first insight into the required temperature range to maximize the H2 release from 1,2-BN cyclohexane and indoline.

  8. Chemisorption On Nanoparticles: An Alternative Mechanism For Hydrogen Storage

    SciTech Connect

    Williamson, A; Reboredo, F; Galli, G

    2004-04-09

    We present first principles, computational predictions of a porous, nano-structured semiconductor material that will reversibly store hydrogen for fuel cell applications. The material is competitive with current metal hydride storage materials, but contains only carbon and silicon, reducing both its cost and environmental impact. Additionally, unlike metal hydrides, the core skeleton structure of this material is unaltered when cycling from full hydrogen storage to full hydrogen depletion, removing engineering complications associated with expansion/contraction of the material.

  9. Synthesis of Ni/Graphene Nanocomposite for Hydrogen Storage.

    PubMed

    Zhou, Chunyu; Szpunar, Jerzy A; Cui, Xiaoyu

    2016-06-22

    We have designed a Ni-graphene composite for hydrogen storage with Ni nanoparticles of 10 nm in size, uniformly dispersed over a graphene substrate. This system exhibits attractive features like high gravimetric density, ambient conditions, and low activation temperature for hydrogen release. When charged at room temperature and an atmospheric hydrogen pressure of 1 bar, it could yield a hydrogen capacity of 0.14 wt %. When hydrogen pressure increased to 60 bar, the sorbent had a hydrogen gravimetric density of 1.18 wt %. The hydrogen release could occur at an operating temperature below 150 °C and completes at 250 °C.

  10. Hydrogen gas storage in fluorinated ultramicroporous tunnel crystal.

    PubMed

    Kataoka, Keisuke; Katagiri, Toshimasa

    2012-08-21

    We report hydrogen storage at an ordinary pressure due to a bottle-neck effect of an ultramicroporous crystal. Stored hydrogen was kept at an ordinary pressure below -110 °C. The amounts of stored hydrogen gas linearly correlated with the initial pressures. These phenomena suggested the ultramicroporous tunnels worked as a molecular gas cylinder.

  11. Borazine-boron nitride hybrid hydrogen storage system

    DOEpatents

    Narula, Chaitanya K [Knoxville, TN; Simonson, J Michael [Knoxville, TN; Maya, Leon [Knoxville, TN; Paine, Robert T [Albuquerque, NM

    2008-04-22

    A hybrid hydrogen storage composition includes a first phase and a second phase adsorbed on the first phase, the first phase including BN for storing hydrogen by physisorption and the second phase including a borazane-borazine system for storing hydrogen in combined form as a hydride.

  12. Hydrogen storage studies of palladium decorated nitrogen doped graphene nanoplatelets.

    PubMed

    Vinayan, B P; Sethupathi, K; Ramaprabhu, S

    2012-08-01

    Hydrogen storage in materials is of significant importance in the present scenario of depleting conventional energy sources. Porous solids such as activated carbon or nanostructured carbon materials have promising future as hydrogen storage media. The hydrogen storage capacity in nanostructured carbon materials can be further enhanced by atomic hydrogen spillover from a supported catalyst. In the present work, the hydrogen storage properties of nitrogen doped graphene nanoplatelets (N-GNP) and palladium decorated nitrogen doped graphene nanoplatelets (Pd/N-GNP) have been investigated. The results show that hydrogen uptake capacity of nitrogen doped graphene nanoplatelets and palladium decorated nitrogen doped graphene nanoplatelets at pressure 32 bar and temperature 25 degrees C is 0.42 wt% and 1.25 wt% respectively. The dispersion of palladium nanoparticles increases the hydrogen storage capacity of nitrogen doped graphene nanoplatelets by 0.83 wt%. This may be due to high dispersion of palladium nanoparticles and strong adhesion between metal and graphene nanoplatelets over the surface of N-GNP, which enhances the spillover mechanism. Thus, an increase in the hydrogen spillover effect and the binding energy between metal nanoparticles and supporting material achieved by nitrogen doping has been observed to result in a higher hydrogen storage capacity of pristine GNP.

  13. Hydrogen Energy Storage (HES) Activities at NREL; NREL (National Renewable Energy Laboratory)

    SciTech Connect

    Eichman, J.

    2015-04-21

    This presentation provides an overview of hydrogen and energy storage, including hydrogen storage pathways and international power-to-gas activities, and summarizes the National Renewable Energy Laboratory's hydrogen energy storage activities and results.

  14. Down Select Report of Chemical Hydrogen Storage Materials, Catalysts, and Spent Fuel Regeneration Processes - May 2008

    SciTech Connect

    Ott, Kevin C.; Linehan, Sue; Lipiecki, Frank; Christopher, Aardahl L.

    2008-05-12

    Chemical Hydrogen Storage Center of Excellence FY2008 Second Quarter Milestone Report: Technical report describing assessment of hydrogen storage materials and progress towards meeting DOE’s hydrogen storage targets.

  15. Optimizing Hydrogen Storage by Doping the LiBH4 +MgH2 Reaction with Various Niobium Based Oxides

    NASA Astrophysics Data System (ADS)

    Hornung, Paul; Walko, Robert; Wenzel, Andrew; Wright, Richard; Dobbins, Tabbetha

    In this study, the effects of doping the dehydrogenation reaction of MgH2 + 2LiBH4 was combined with 5 mole% of three different Niobium based oxides (Nb2O5, NbO2, and LiNbO3). The compounds were mixed using high energy ball milling, and then heated using an air tight heating stage. We looked for changes in the Raman spectra as temperature increased (up to 350C) as an indication of hydrogen desorption reaction. We found that milled LiBH4 undergoes significant changes in Raman spectra during heating to 130C. MgH2 undergoes significant changes when comparing before and after milling--but in each case, the spectral peaks remain unchanged during heating to 350C. The sample with LiNbO3 exhibited a concrete change in Raman spectrum at 300 C while the sample doped with Nb2O5 underwent a change in spectra at 170C. The sample doped with NbO2 showed little change in spectra when the samples were heated up to 350C. Further studies are underway to examine the nature of the changes in the Raman spectra using X-ray diffraction and residual gas analysis.

  16. Second Generation MOF's for Hydrogen Storage

    SciTech Connect

    Adam Matzger

    2008-05-31

    This final technical report summarizes work exploring strategies to generate second generation metal organic frameworks (MOFs). These strategies were (a) the formation of interpenetrated frameworks and (b) the generation of coordinatively unsaturated metal centers (open metal sites). In the first phase of the project the effectiveness of these strategies was evaluated experimentally by measuring the saturation hydrogen uptake at high pressure and low temperature of 14 MOFs. The results of these studies demonstrated that surface area is the most useful parameter that correlates with ultimate hydrogen capacity. The strategy of interpenetration has so far failed to produce MOFs with high surface areas and therefore high saturation capacities for hydrogen have not been achieved. The incorporation of coordinatively unsaturated metal centers, however, is a promising strategy that allows higher heats of H2 adsorption to be realized without compromising surface area. Based on these initial findings, research efforts in phase two have concentrated on the discovery of new ultrahigh surface area materials with metal centers capable of supporting coordinative unsaturation without structural collapse. One approach has been the synthesis of new organic linkers that have more exposed edges, which is a factor that contributes to increasing surface area, at least when considering subunits of graphene sheets. Another strategy has been to synthesize MOFs with reduced symmetry linkers in order to generate structure types that are less likely to interpenetrate. Successful implementation of these strategies has resulted in the synthesis of 7 new compounds one of which is the highest surface area Cu based MOF reported to date.

  17. Hydrogen storage in sodium aluminum hydride.

    SciTech Connect

    Ozolins, Vidvuds; Herberg, J.L. (Lawrence Livermore National Laboratories, Livermore, CA); McCarty, Kevin F.; Maxwell, Robert S. (Lawrence Livermore National Laboratories, Livermore, CA); Stumpf, Roland Rudolph; Majzoub, Eric H.

    2005-11-01

    Sodium aluminum hydride, NaAlH{sub 4}, has been studied for use as a hydrogen storage material. The effect of Ti, as a few mol. % dopant in the system to increase kinetics of hydrogen sorption, is studied with respect to changes in lattice structure of the crystal. No Ti substitution is found in the crystal lattice. Electronic structure calculations indicate that the NaAlH{sub 4} and Na{sub 3}AlH{sub 6} structures are complex-ionic hydrides with Na{sup +} cations and AlH{sub 4}{sup -} and AlH{sub 6}{sup 3-} anions, respectively. Compound formation studies indicate the primary Ti-compound formed when doping the material at 33 at. % is TiAl{sub 3} , and likely Ti-Al compounds at lower doping rates. A general study of sorption kinetics of NaAlH{sub 4}, when doped with a variety of Ti-halide compounds, indicates a uniform response with the kinetics similar for all dopants. NMR multiple quantum studies of solution-doped samples indicate solvent interaction with the doped alanate. Raman spectroscopy was used to study the lattice dynamics of NaAlH{sub 4}, and illustrated the molecular ionic nature of the lattice as a separation of vibrational modes between the AlH{sub 4}{sup -} anion-modes and lattice-modes. In-situ Raman measurements indicate a stable AlH{sub 4}{sup -} anion that is stable at the melting temperature of NaAlH{sub 4}, indicating that Ti-dopants must affect the Al-H bond strength.

  18. Thermodynamics and Kinetics of Phase Transformations in Hydrogen Storage Materials

    SciTech Connect

    Ceder, Gerbrand; Marzari, Nicola

    2011-08-31

    The aim of this project is to develop and apply computational materials science tools to determine and predict critical properties of hydrogen storage materials. By better understanding the absorption/desorption mechanisms and characterizing their physical properties it is possible to explore and evaluate new directions for hydrogen storage materials. Particular emphasis is on the determination of the structure and thermodynamics of hydrogen storage materials, the investigation of microscopic mechanisms of hydrogen uptake and release in various materials and the role of catalysts in this process. As a team we have decided to focus on a single material, NaAlH{sub 4}, in order to fully be able to study the many aspects of hydrogen storage. We have focused on phase stability, mass transport and size-dependent reaction mechanisms in this material.

  19. Enhancement in hydrogen storage in carbon nanotubes under modified conditions

    NASA Astrophysics Data System (ADS)

    Banerjee, Soumik; Puri, Ishwar K.

    2008-04-01

    We investigate the hydrogen adsorbing characteristics of single-walled carbon nanotubes (CNTs) through fundamental molecular dynamics simulations that characterize the role of ambient pressure and temperature, the presence of surface charges on the CNTs, inclusion of metal ion interconnects, and nanocapillary effects. While the literature suggests that hydrogen spillover due to the presence of metallic contaminants enhances storage on and inside the nanotubes, we find this to be significant for alkali and not transition metals. Charging the CNT surfaces does not significantly enhance hydrogen storage. We find that the bulk of the hydrogen storage occurs inside CNTs due to their nanocapillarity effect. Storage is much more dependent on external thermodynamic conditions such as the temperature and the pressure than on these facets of the CNT structure. The dependence of storage on the external thermodynamic conditions is analyzed and the optimal range of operating conditions is identified.

  20. Graphene nanostructures as tunable storage media for molecular hydrogen

    PubMed Central

    Patchkovskii, Serguei; Tse, John S.; Yurchenko, Sergei N.; Zhechkov, Lyuben; Heine, Thomas; Seifert, Gotthard

    2005-01-01

    Many methods have been proposed for efficient storage of molecular hydrogen for fuel cell applications. However, despite intense research efforts, the twin U.S. Department of Energy goals of 6.5% mass ratio and 62 kg/m3 volume density has not been achieved either experimentally or via theoretical simulations on reversible model systems. Carbon-based materials, such as carbon nanotubes, have always been regarded as the most attractive physisorption substrates for the storage of hydrogen. Theoretical studies on various model graphitic systems, however, failed to reach the elusive goal. Here, we show that insufficiently accurate carbon–H2 interaction potentials, together with the neglect and incomplete treatment of the quantum effects in previous theoretical investigations, led to misleading conclusions for the absorption capacity. A proper account of the contribution of quantum effects to the free energy and the equilibrium constant for hydrogen adsorption suggest that the U.S. Department of Energy specification can be approached in a graphite-based physisorption system. The theoretical prediction can be realized by optimizing the structures of nano-graphite platelets (graphene), which are light-weight, cheap, chemically inert, and environmentally benign. PMID:16020537

  1. Graphene nanostructures as tunable storage media for molecular hydrogen

    NASA Astrophysics Data System (ADS)

    Patchkovskii, Serguei; Tse, John S.; Yurchenko, Sergei N.; Zhechkov, Lyuben; Heine, Thomas; Seifert, Gotthard

    2005-07-01

    Many methods have been proposed for efficient storage of molecular hydrogen for fuel cell applications. However, despite intense research efforts, the twin U.S. Department of Energy goals of 6.5% mass ratio and 62 kg/m3 volume density has not been achieved either experimentally or via theoretical simulations on reversible model systems. Carbon-based materials, such as carbon nanotubes, have always been regarded as the most attractive physisorption substrates for the storage of hydrogen. Theoretical studies on various model graphitic systems, however, failed to reach the elusive goal. Here, we show that insufficiently accurate carbon-H2 interaction potentials, together with the neglect and incomplete treatment of the quantum effects in previous theoretical investigations, led to misleading conclusions for the absorption capacity. A proper account of the contribution of quantum effects to the free energy and the equilibrium constant for hydrogen adsorption suggest that the U.S. Department of Energy specification can be approached in a graphite-based physisorption system. The theoretical prediction can be realized by optimizing the structures of nano-graphite platelets (graphene), which are light-weight, cheap, chemically inert, and environmentally benign. This paper was submitted directly (Track II) to the PNAS office.Abbreviations: DOE, U.S. Department of Energy; DOS, density-of-states; LJ, Lennard-Jones MP2, second-order Møller-Plessett PAH, polycyclic aromatic hydrocarbon; PES, potential energy surface.

  2. HIERARCHICAL METHODOLOGY FOR MODELING HYDROGEN STORAGE SYSTEMS PART II: DETAILED MODELS

    SciTech Connect

    Hardy, B; Donald L. Anton, D

    2008-12-22

    There is significant interest in hydrogen storage systems that employ a media which either adsorbs, absorbs or reacts with hydrogen in a nearly reversible manner. In any media based storage system the rate of hydrogen uptake and the system capacity is governed by a number of complex, coupled physical processes. To design and evaluate such storage systems, a comprehensive methodology was developed, consisting of a hierarchical sequence of models that range from scoping calculations to numerical models that couple reaction kinetics with heat and mass transfer for both the hydrogen charging and discharging phases. The scoping models were presented in Part I [1] of this two part series of papers. This paper describes a detailed numerical model that integrates the phenomena occurring when hydrogen is charged and discharged. A specific application of the methodology is made to a system using NaAlH{sub 4} as the storage media.

  3. Hydrogen Storage Materials for Mobile and Stationary Applications: Current State of the Art.

    PubMed

    Lai, Qiwen; Paskevicius, Mark; Sheppard, Drew A; Buckley, Craig E; Thornton, Aaron W; Hill, Matthew R; Gu, Qinfen; Mao, Jianfeng; Huang, Zhenguo; Liu, Hua Kun; Guo, Zaiping; Banerjee, Amitava; Chakraborty, Sudip; Ahuja, Rajeev; Aguey-Zinsou, Kondo-Francois

    2015-09-07

    One of the limitations to the widespread use of hydrogen as an energy carrier is its storage in a safe and compact form. Herein, recent developments in effective high-capacity hydrogen storage materials are reviewed, with a special emphasis on light compounds, including those based on organic porous structures, boron, nitrogen, and aluminum. These elements and their related compounds hold the promise of high, reversible, and practical hydrogen storage capacity for mobile applications, including vehicles and portable power equipment, but also for the large scale and distributed storage of energy for stationary applications. Current understanding of the fundamental principles that govern the interaction of hydrogen with these light compounds is summarized, as well as basic strategies to meet practical targets of hydrogen uptake and release. The limitation of these strategies and current understanding is also discussed and new directions proposed. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Technical and economic aspects of hydrogen storage in metal hydrides

    NASA Technical Reports Server (NTRS)

    Schmitt, R.

    1981-01-01

    The recovery of hydrogen from such metal hydrides as LiH, MgH2, TiH2, CaH2 and FeTiH compounds is studied, with the aim of evaluating the viability of the technique for the storage of hydrogen fuel. The pressure-temperature dependence of the reactions, enthalpies of formation, the kinetics of the hydrogen absorption and desorption, and the mechanical and chemical stability of the metal hydrides are taken into account in the evaluation. Economic aspects are considered. Development of portable metal hydride hydrogen storage reservoirs is also mentioned.

  5. ZnO nanorod electrodes for hydrogen evolution and storage

    NASA Astrophysics Data System (ADS)

    Harinipriya, S.; Usmani, B.; Rogers, D. J.; Sandana, V. E.; Teherani, F. Hosseini; Lusson, A.; Bove, P.; Drouhin, H.-J.; Razeghi, M.

    2012-02-01

    Due to the attractive combination of a relatively high specific heat of combustion with a large specific energy capacity, molecular hydrogen (H2) is being investigated for use as an alternative to fossil fuels. Energy-efficient H2 production and safe storage remain key technical obstacles to implementation of an H2 based economy, however. ZnO has been investigated for use as an alternative photocatalytic electrode to TiO2 for solarpowered photo-electro-chemical (PEC) electrolysis, in which H2 is generated by direct water splitting in a cell with a metal cathode and a semiconducting anode. In this investigation, ZnO NR grown on Si (100) substrates by pulsed laser deposition were investigated for use as electrodes in the Hydrogen Evolution Reaction (HER). The electrochemical potential and Fermi energy of the ZnO NR were estimated from the electrochemical current density in acid and alkaline solutions via phenomenological thermodynamic analysis. As well as acting as an effective electrocalytic cathode, the ZnO NR appear to operate as a hydrogen reservoir. These results indicate that the ZnO NR have excellent potential for the storage of evolved H2.

  6. Hydrogen storage in platinum decorated hydrogen exfoliated graphene sheets by spillover mechanism.

    PubMed

    P, Divya; Ramaprabhu, S

    2014-12-28

    Development of lightweight materials with high hydrogen storage capacities is a great challenge for the hydrogen economy. Here, we report high pressure hydrogen adsorption-desorption studies of platinum-decorated hydrogen-exfoliated graphene sheets (Pt-HEG). Pt-HEG shows a maximum hydrogen uptake capacity of 1.4 wt% at 25 °C and 3 MPa. Analysis of the isosteric heat of adsorption provides evidence of spillover mechanism.

  7. Reversible Interconversion between 2,5-Dimethylpyrazine and 2,5-Dimethylpiperazine by Iridium-Catalyzed Hydrogenation/Dehydrogenation for Efficient Hydrogen Storage.

    PubMed

    Fujita, Ken-Ichi; Wada, Tomokatsu; Shiraishi, Takumi

    2017-08-28

    A new hydrogen storage system based on the hydrogenation and dehydrogenation of nitrogen heterocyclic compounds, employing a single iridium catalyst, has been developed. Efficient hydrogen storage using relatively small amounts of solvent compared with previous systems was achieved by this new system. Reversible transformations between 2,5-dimethylpyrazine and 2,5-dimethylpiperazine, accompanied by the uptake and release of three equivalents of hydrogen, could be repeated almost quantitatively at least four times without any loss of efficiency. Furthermore, hydrogen storage under solvent-free conditions was also accomplished. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. An experiment to evaluate liquid hydrogen storage in space

    NASA Technical Reports Server (NTRS)

    Eberhardt, R. N.; Fester, D. A.; Johns, W. A.; Marino, J. S.

    1981-01-01

    The design and verification of a Cryogenic Fluid Management Experiment for orbital operation on the Shuttle is described. The experiment will furnish engineering data to establish design criteria for storage and supply of cryogenic fluids, mainly hydrogen, for use in low gravity environments. The apparatus comprises an LAD (liquid acquisition device) and a TVS (thermodynamic vent system). The hydrogen will be either vented or forced out by injected helium and the flow rates will be monitored. The data will be compared with ground-based simulations to determine optimal flow rates for the pressurizing gas and the release of the cryogenic fluid. It is noted that tests on a one-g, one-third size LAD system are under way.

  9. An experiment to evaluate liquid hydrogen storage in space

    NASA Technical Reports Server (NTRS)

    Eberhardt, R. N.; Fester, D. A.; Johns, W. A.; Marino, J. S.

    1981-01-01

    The design and verification of a Cryogenic Fluid Management Experiment for orbital operation on the Shuttle is described. The experiment will furnish engineering data to establish design criteria for storage and supply of cryogenic fluids, mainly hydrogen, for use in low gravity environments. The apparatus comprises an LAD (liquid acquisition device) and a TVS (thermodynamic vent system). The hydrogen will be either vented or forced out by injected helium and the flow rates will be monitored. The data will be compared with ground-based simulations to determine optimal flow rates for the pressurizing gas and the release of the cryogenic fluid. It is noted that tests on a one-g, one-third size LAD system are under way.

  10. in-situ chemistry mapping of hydrogen storage materials by neutron diffraction

    SciTech Connect

    Payzant, E Andrew; Bowman Jr, Robert C; Johnson, Terry A; Jorgensen, Scott W

    2013-01-01

    Neutron diffraction was used to nondestructively study the microstructures for two hydrogen storage media systems. In the first case, sodium alanate based hydrogen storage is a vehicle-scale candidate system developed by Sandia/GM. Neutron scattering was used to determine the distribution of phases in the storage media at different hydrogen loading levels, to help understand the absorption/desorption of hydrogen in large-scale systems. This study also included a 3D neutron tomographic study of the microstructure. In the second case, tin-doped lanthanum nickel alloys have been studied at JPL for space-based applications, for which the gradual degradation of the material due to segregation and disproportionation of phases is a known problem. A regenerative process developed to restore the storage properties of these alloys was studied, using in-situ neutron diffraction to relate the microstructure to the thermodynamic simulations.

  11. Storage, generation, and use of hydrogen

    DOEpatents

    McClaine, Andrew W.; Rolfe, Jonathan L.; Larsen, Christopher A.; Konduri, Ravi K.

    2006-05-30

    A composition comprising a carrier liquid; a dispersant; and a chemical hydride. The composition can be used in a hydrogen generator to generate hydrogen for use, e.g., as a fuel. A regenerator recovers elemental metal from byproducts of the hydrogen generation process.

  12. Energy storage possibilities of atomic hydrogen

    NASA Technical Reports Server (NTRS)

    Etters, R. D.; Dugan, J. V., Jr.; Palmer, R.

    1976-01-01

    The possibility of storing large amounts of energy in a free radical system such as atomic hydrogen is analyzed. Attention is focused on theoretical calculations of the ground state properties of spin-aligned atomic triplet hydrogen, deuterium, and tritium. The solid-liquid phase transition in atomic hydrogen is also examined.

  13. Hydrogen transmission/storage with a metal hydride/organic slurry

    SciTech Connect

    Breault, R.W.; Rolfe, J.; McClaine, A.

    1998-08-01

    Thermo Power Corporation has developed a new approach for the production, transmission, and storage of hydrogen. In this approach, a chemical hydride slurry is used as the hydrogen carrier and storage media. The slurry protects the hydride from unanticipated contact with moisture in the air and makes the hydride pumpable. At the point of storage and use, a chemical hydride/water reaction is used to produce high-purity hydrogen. An essential feature of this approach is the recovery and recycle of the spent hydride at centralized processing plants, resulting in an overall low cost for hydrogen. This approach has two clear benefits: it greatly improves energy transmission and storage characteristics of hydrogen as a fuel, and it produces the hydrogen carrier efficiently and economically from a low cost carbon source. The preliminary economic analysis of the process indicates that hydrogen can be produced for $3.85 per million Btu based on a carbon cost of $1.42 per million Btu and a plant sized to serve a million cars per day. This compares to current costs of approximately $9.00 per million Btu to produce hydrogen from $3.00 per million Btu natural gas, and $25 per million Btu to produce hydrogen by electrolysis from $0.05 per Kwh electricity. The present standard for production of hydrogen from renewable energy is photovoltaic-electrolysis at $100 to $150 per million Btu.

  14. Hydrogen storage: the remaining scientific and technological challenges.

    PubMed

    Felderhoff, Michael; Weidenthaler, Claudia; von Helmolt, Rittmar; Eberle, Ulrich

    2007-06-07

    To ensure future worldwide mobility, hydrogen storage in combination with fuel cells for on-board automotive applications is one of the most challenging issues. Potential solid-state solutions have to fulfil operating requirements defined by the fuel cell propulsion system. Important requirements are also defined by customer demands such as cost, overall fuel capacity, refuelling time and efficiency. It seems that currently none of the different storage solid state materials can reach the required storage densities for a hydrogen-powered vehicle. New strategies for storage systems are necessary to fulfil the requirements for a broad introduction of automotive fuel cell powertrains to the market. The combination of different storage systems may provide a possible solution to store sufficiently high amounts of hydrogen.

  15. Material synthesis and hydrogen storage of palladium-rhodium alloy.

    SciTech Connect

    Lavernia, Enrique J.; Yang, Nancy Y. C.; Ong, Markus D.

    2011-08-01

    Pd and Pd alloys are candidate material systems for Tr or H storage. We have actively engaged in material synthesis and studied the material science of hydrogen storage for Pd-Rh alloys. In collaboration with UC Davis, we successfully developed/optimized a supersonic gas atomization system, including its processing parameters, for Pd-Rh-based alloy powders. This optimized system and processing enable us to produce {le} 50-{mu}m powders with suitable metallurgical properties for H-storage R&D. In addition, we studied hydrogen absorption-desorption pressure-composition-temperature (PCT) behavior using these gas-atomized Pd-Rh alloy powders. The study shows that the pressure-composition-temperature (PCT) behavior of Pd-Rh alloys is strongly influenced by its metallurgy. The plateau pressure, slope, and H/metal capacity are highly dependent on alloy composition and its chemical distribution. For the gas-atomized Pd-10 wt% Rh, the absorption plateau pressure is relatively high and consistent. However, the absorption-desorption PCT exhibits a significant hysteresis loop that is not seen from the 30-nm nanopowders produced by chemical precipitation. In addition, we observed that the presence of hydrogen introduces strong lattice strain, plastic deformation, and dislocation networking that lead to material hardening, lattice distortions, and volume expansion. The above observations suggest that the H-induced dislocation networking is responsible for the hysteresis loop seen in the current atomized Pd-10 wt% Rh powders. This conclusion is consistent with the hypothesis suggested by Flanagan and others (Ref 1) that plastic deformation or dislocations control the hysteresis loop.

  16. Chemical storage of hydrogen in few-layer graphene

    PubMed Central

    Subrahmanyam, K. S.; Kumar, Prashant; Maitra, Urmimala; Govindaraj, A.; Hembram, K. P. S. S.; Waghmare, Umesh V.; Rao, C. N. R.

    2011-01-01

    Birch reduction of few-layer graphene samples gives rise to hydrogenated samples containing up to 5 wt % of hydrogen. Spectroscopic studies reveal the presence of sp3 C-H bonds in the hydrogenated graphenes. They, however, decompose readily on heating to 500 °C or on irradiation with UV or laser radiation releasing all the hydrogen, thereby demonstrating the possible use of few-layer graphene for chemical storage of hydrogen. First-principles calculations throw light on the mechanism of dehydrogenation that appears to involve a significant reconstruction and relaxation of the lattice. PMID:21282617

  17. Thermal management technology for hydrogen storage: Fullerene option

    SciTech Connect

    Wang, J.C.; Chen, F.C.; Murphy, R.W.

    1996-10-01

    Fullerenes are selected as the first option for investigating advanced thermal management technologies for hydrogen storage because of their potentially high volumetric and gravimetric densities. Experimental results indicate that about 6 wt% of hydrogen (corresponding to C{sub 60}H{sub 48}) can be added to and taken out of fullerenes. A model assuming thermally activated hydrogenation and dehydrogenation processes was developed to explain the experimental findings. The activation energies were estimated to be 100 and 160 kJ/mole (1.0 and 1.6 eV/H{sub 2}) for the hydrogenation and dehydrogenation processes, respectively. The difference is interpreted as the heat released during hydrogenation. There are indications that the activation energies and the heat of hydrogenation can be modified by the use of catalysts. Preliminary hydrogen storage simulations for a conceptually simple device were performed. A 1-m long hollow metal cylinder with an inner diameter of 0.02 m was assumed to be filled with fullerene powders. The results indicate that the thermal diffusivity of the fullerenes controls the hydrogenation and dehydrogenation rates. The rates can be significantly modified by changing the thermal diffusivity of the material inside the cylinder, e.g., by incorporating a metal mesh. Results from the simulation suggest that thermal management is essential for efficient hydrogen storage devices using fullerenes. While the preliminary models developed in this study explain some of the observation, more controlled experiments, rigorous model development, and physical property determinations are needed for the development of practical hydrogen storage devices. The use of catalysts to optimize the hydrogen storage characteristics of fullerenes also needs to be pursued. Future cooperative work between Oak Ridge National Laboratory (ORNL) and Material & Electrochemical Research Corporation (MER) is planned to address these needs.

  18. Storage of hydrogen at 303 K in graphite slitlike pores from grand canonical Monte Carlo simulation.

    PubMed

    Kowalczyk, Piotr; Tanaka, Hideki; Hołyst, Robert; Kaneko, Katsumi; Ohmori, Takumi; Miyamoto, Junichi

    2005-09-15

    Grand canonical Monte Carlo (GCMC) simulations were used for the modeling of the hydrogen adsorption in idealized graphite slitlike pores. In all simulations, quantum effects were included through the Feynman and Hibbs second-order effective potential. The simulated surface excess isotherms of hydrogen were used for the determination of the total hydrogen storage, density of hydrogen in graphite slitlike pores, distribution of pore sizes and volumes, enthalpy of adsorption per mole, total surface area, total pore volume, and average pore size of pitch-based activated carbon fibers. Combining experimental results with simulations reveals that the density of hydrogen in graphite slitlike pores at 303 K does not exceed 0.014 g/cm(3), that is, 21% of the liquid-hydrogen density at the triple point. The optimal pore size for the storage of hydrogen at 303 K in the considered pore geometry depends on the pressure of storage. For lower storage pressures, p < 30MPa, the optimal pore width is equal to a 2.2 collision diameter of hydrogen (i.e., 0.65 nm), whereas, for p congruent with 50MPa, the pore width is equal to an approximately 7.2 collision diameter of hydrogen (i.e., 2.13 nm). For the wider pores, that is, the pore width exceeds a 7.2 collision diameter of hydrogen, the surface excess of hydrogen adsorption is constant. The importance of quantum effects is recognized in narrow graphite slitlike pores in the whole range of the hydrogen pressure as well as in wider ones at high pressures of bulk hydrogen. The enthalpies of adsorption per mole for the considered carbonaceous materials are practically constant with hydrogen loading and vary within the narrow range q(st) congruent with 7.28-7.85 kJ/mol. Our systematic study of hydrogen adsorption at 303 K in graphite slitlike pores gives deep insight into the timely problem of hydrogen storage as the most promising source of clean energy. The calculated maximum storage of hydrogen is equal to approximately 1.4 wt

  19. Some recent efforts in chemical hydrogen storage at Loa Alamos

    SciTech Connect

    Gordon, John C; Davis, Benjamin L; Burrell, Anthony K; Nakagawa, Tessui; Ott, Kevin C; Smythe, Nathan C; Sutton, Andrew D; Henson, Neil J; Baker, R. Thomas; Hamilton, Charles W; Dixon, David A; Garner Ill, Edward B; Vasiliu, Monica

    2010-12-08

    Within the transportation sector, a necessity towards realizing the use of hydrogen (H{sub 2}) as an alternative fuel, is its storage for controlled delivery. The U.S. DOE's Centers of Excellence (CoE) in H{sub 2} storage have pursued different methodologies (metal hydrides, chemical hydrides, and sorbents), for the express purpose of supplanting gasoline's current > 300 mile driving range. Chemical H{sub 2} storage has been dominated by one material, ammonia borane (H3B-NH3, AB), due to its high gravimetric capacity of H{sub 2} (19.6 wt %) and low molecular weight (30.7 g mol{sup -1} ). As such, a number of publications have described H{sub 2} release from amine boranes, yielding various rates depending on the method applied. The viability of any storage system is also dependent on efficient recyclability. Within our CoE we have thus endeavored to find efficient base-metal catalyzed AB dehydrogenation pathways and regeneration schemes for the spent fuel from H{sub 2} depleted AB. We will present some recent results in these areas in this vein.

  20. Carbon Dioxide-Free Hydrogen Production with Integrated Hydrogen Separation and Storage.

    PubMed

    Dürr, Stefan; Müller, Michael; Jorschick, Holger; Helmin, Marta; Bösmann, Andreas; Palkovits, Regina; Wasserscheid, Peter

    2017-01-10

    An integration of CO2 -free hydrogen generation through methane decomposition coupled with hydrogen/methane separation and chemical hydrogen storage through liquid organic hydrogen carrier (LOHC) systems is demonstrated. A potential, very interesting application is the upgrading of stranded gas, for example, gas from a remote gas field or associated gas from off-shore oil drilling. Stranded gas can be effectively converted in a catalytic process by methane decomposition into solid carbon and a hydrogen/methane mixture that can be directly fed to a hydrogenation unit to load a LOHC with hydrogen. This allows for a straight-forward separation of hydrogen from CH4 and conversion of hydrogen to a hydrogen-rich LOHC material. Both, the hydrogen-rich LOHC material and the generated carbon on metal can easily be transported to destinations of further industrial use by established transport systems, like ships or trucks.

  1. Hydrogen gas storage in fluorinated ultramicroporous tunnel crystal

    NASA Astrophysics Data System (ADS)

    Kataoka, Keisuke; Katagiri, Toshimasa

    2012-07-01

    We report hydrogen storage at an ordinary pressure due to a bottle-neck effect of an ultramicroporous crystal. Stored hydrogen was kept at an ordinary pressure below -110 °C. The amounts of stored hydrogen gas linearly correlated with the initial pressures. These phenomena suggested the ultramicroporous tunnels worked as a molecular gas cylinder.We report hydrogen storage at an ordinary pressure due to a bottle-neck effect of an ultramicroporous crystal. Stored hydrogen was kept at an ordinary pressure below -110 °C. The amounts of stored hydrogen gas linearly correlated with the initial pressures. These phenomena suggested the ultramicroporous tunnels worked as a molecular gas cylinder. Electronic supplementary information (ESI) available. CCDC 246922. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c2nr30940h

  2. Low-Cost Precursors to Novel Hydrogen Storage Materials

    SciTech Connect

    Suzanne W. Linehan; Arthur A. Chin; Nathan T. Allen; Robert Butterick; Nathan T. Kendall; I. Leo Klawiter; Francis J. Lipiecki; Dean M. Millar; David C. Molzahn; Samuel J. November; Puja Jain; Sara Nadeau; Scott Mancroni

    2010-12-31

    From 2005 to 2010, The Dow Chemical Company (formerly Rohm and Haas Company) was a member of the Department of Energy Center of Excellence on Chemical Hydrogen Storage, which conducted research to identify and develop chemical hydrogen storage materials having the potential to achieve DOE performance targets established for on-board vehicular application. In collaboration with Center co-leads Los Alamos National Laboratory (LANL) and Pacific Northwest National Laboratory (PNNL), and other Center partners, Dow's efforts were directed towards defining and evaluating novel chemistries for producing chemical hydrides and processes for spent fuel regeneration. In Phase 1 of this project, emphasis was placed on sodium borohydride (NaBH{sub 4}), long considered a strong candidate for hydrogen storage because of its high hydrogen storage capacity, well characterized hydrogen release chemistry, safety, and functionality. Various chemical pathways for regenerating NaBH{sub 4} from spent sodium borate solution were investigated, with the objective of meeting the 2010/2015 DOE targets of $2-3/gal gasoline equivalent at the pump ($2-3/kg H{sub 2}) for on-board hydrogen storage systems and an overall 60% energy efficiency. With the September 2007 No-Go decision for NaBH{sub 4} as an on-board hydrogen storage medium, focus was shifted to ammonia borane (AB) for on-board hydrogen storage and delivery. However, NaBH{sub 4} is a key building block to most boron-based fuels, and the ability to produce NaBH{sub 4} in an energy-efficient, cost-effective, and environmentally sound manner is critical to the viability of AB, as well as many leading materials under consideration by the Metal Hydride Center of Excellence. Therefore, in Phase 2, research continued towards identifying and developing a single low-cost NaBH4 synthetic route for cost-efficient AB first fill, and conducting baseline cost estimates for first fill and regenerated AB using a variety of synthetic routes. This project

  3. Outlook and Challenges for Hydrogen Storage in Nanoporous Materials

    SciTech Connect

    Broom, D. P.; Webb, C. J.; Hurst, Katherine E.; Parilla, Philip A.; Gennett, Thomas; Brown, C. M.; Zacharia, R.; Tylianakis, E.; Klontzas, E.; Froudakis, G. E.; Steriotis, T. A.; Trikalitis, P. N.; Anton, D. L.; Hardy, B.; Tamburello, D.; Corgnale, C.; van Hassel, B. A.; Cossement, D.; Chahine, R.; Hirscher, M.

    2016-02-16

    Considerable progress has been made recently in the use of nanoporous materials for hydrogen storage. In our article, the current status of the field and future challenges are discussed, ranging from important open fundamental questions, such as the density and volume of the adsorbed phase and its relationship to overall storage capacity, to the development of new functional materials and complete storage system design. With regard to fundamentals, the use of neutron scattering to study adsorbed H2, suitable adsorption isotherm equations, and the accurate computational modelling and simulation of H2 adsorption are discussed. We cover new materials and they include flexible metal–organic frameworks, core–shell materials, and porous organic cage compounds. The article concludes with a discussion of the experimental investigation of real adsorptive hydrogen storage tanks, the improvement in the thermal conductivity of storage beds, and new storage system concepts and designs.

  4. Outlook and Challenges for Hydrogen Storage in Nanoporous Materials

    DOE PAGES

    Broom, D. P.; Webb, C. J.; Hurst, Katherine E.; ...

    2016-02-16

    Considerable progress has been made recently in the use of nanoporous materials for hydrogen storage. In our article, the current status of the field and future challenges are discussed, ranging from important open fundamental questions, such as the density and volume of the adsorbed phase and its relationship to overall storage capacity, to the development of new functional materials and complete storage system design. With regard to fundamentals, the use of neutron scattering to study adsorbed H2, suitable adsorption isotherm equations, and the accurate computational modelling and simulation of H2 adsorption are discussed. We cover new materials and they includemore » flexible metal–organic frameworks, core–shell materials, and porous organic cage compounds. The article concludes with a discussion of the experimental investigation of real adsorptive hydrogen storage tanks, the improvement in the thermal conductivity of storage beds, and new storage system concepts and designs.« less

  5. Charge induced enhancement of adsorption for hydrogen storage materials

    NASA Astrophysics Data System (ADS)

    Sun, Xiang

    2009-12-01

    The rising concerns about environmental pollution and global warming have facilitated research interest in hydrogen energy as an alternative energy source. To apply hydrogen for transportations, several issues have to be solved, within which hydrogen storage is the most critical problem. Lots of materials and devices have been developed; however, none is able to meet the DOE storage target. The primary issue for hydrogen physisorption is a weak interaction between hydrogen and the surface of solid materials, resulting negligible adsorption at room temperature. To solve this issue, there is a need to increase the interaction between the hydrogen molecules and adsorbent surface. In this study, intrinsic electric dipole is investigated to enhance the adsorption energy. The results from the computer simulation of single ionic compounds with hydrogen molecules to form hydrogen clusters showed that electrical charge of substances plays an important role in generation of attractive interaction with hydrogen molecules. In order to further examine the effects of static interaction on hydrogen adsorption, activated carbon with a large surface area was impregnated with various ionic salts including LiCl, NaCl, KCl, KBr, and NiCl2 and their performance for hydrogen storage was evaluated by using a volumetric method. Corresponding computer simulations have been carried out by using DFT (Density Functional Theory) method combined with point charge arrays. Both experimental and computational results prove that the adsorption capacity of hydrogen and its interaction with the solid materials increased with electrical dipole moment. Besides the intrinsic dipole, an externally applied electric field could be another means to enhance hydrogen adsorption. Hydrogen adsorption under an applied electric field was examined by using porous nickel foil as electrodes. Electrical signals showed that adsorption capacity increased with the increasing of gas pressure and external electric voltage

  6. Use of triphenyl phosphate as risk mitigant for metal amide hydrogen storage materials

    DOEpatents

    Cortes-Concepcion, Jose A.; Anton, Donald L.

    2016-04-26

    A process in a resulting product of the process in which a hydrogen storage metal amide is modified by a ball milling process using an additive of TPP. The resulting product provides for a hydrogen storage metal amide having a coating that renders the hydrogen storage metal amide resistant to air, ambient moisture, and liquid water while improving useful hydrogen storage and release kinetics.

  7. Atomic hydrogen storage method and apparatus

    NASA Technical Reports Server (NTRS)

    Woollam, J. A. (Inventor)

    1980-01-01

    Atomic hydrogen, for use as a fuel or as an explosive, is stored in the presence of a strong magnetic field in exfoliated layered compounds such as molybdenum disulfide or an elemental layer material such as graphite. The compounds maintained at liquid helium temperatures and the atomic hydrogen is collected on the surfaces of the layered compound which are exposed during delamination (exfoliation). The strong magnetic field and the low temperature combine to prevent the atoms of hydrogen from recombining to form molecules.

  8. Density functional theory for hydrogen storage materials: successes and opportunities

    NASA Astrophysics Data System (ADS)

    Hector, L. G., Jr.; Herbst, J. F.

    2008-02-01

    Solid state systems for hydrogen storage continue to be the focus of considerable international research, driven to a large extent by technological demands, especially for mobile applications. Density functional theory (DFT) has become a valuable tool in this effort. It has greatly expanded our understanding of the properties of known hydrides, including electronic structure, hydrogen bonding character, enthalpy of formation, elastic behavior, and vibrational energetics. Moreover, DFT holds substantial promise for guiding the discovery of new materials. In this paper we discuss, within the context of results from our own work, some successes and a few shortcomings of state-of-the-art DFT as applied to hydrogen storage materials.

  9. New Ti-decorated B40 fullerene as a promising hydrogen storage material

    PubMed Central

    Dong, Huilong; Hou, Tingjun; Lee, Shuit-Tong; Li, Youyong

    2015-01-01

    The newly found B40 is the first experimentally observed all-boron fullerene and has potential applications in hydrogen storage. Here we investigate the binding ability and hydrogen storage capacity of Ti-decorated B40 fullerene based on DFT calculations. Our results indicate that Ti shows excellent binding capability to B40 compared with other transition metals. The B40 fullerene coated by 6 Ti atoms (Ti6B40) can store up to 34 H2 molecules, corresponding to a maximum gravimetric density of 8.7 wt%. It takes 0.2-0.4 eV/H2 to add one H2 molecule, which assures reversible storage of H2 molecules under ambient conditions. The evaluated reversible storage capacity is 6.1 wt%. Our results demonstrate that the new Ti-decorated B40 fullerene is a promising hydrogen storage material with high capacity. PMID:25943256

  10. New Ti-decorated B40 fullerene as a promising hydrogen storage material.

    PubMed

    Dong, Huilong; Hou, Tingjun; Lee, Shuit-Tong; Li, Youyong

    2015-05-06

    The newly found B40 is the first experimentally observed all-boron fullerene and has potential applications in hydrogen storage. Here we investigate the binding ability and hydrogen storage capacity of Ti-decorated B40 fullerene based on DFT calculations. Our results indicate that Ti shows excellent binding capability to B40 compared with other transition metals. The B40 fullerene coated by 6 Ti atoms (Ti6B40) can store up to 34 H2 molecules, corresponding to a maximum gravimetric density of 8.7 wt%. It takes 0.2-0.4 eV/H2 to add one H2 molecule, which assures reversible storage of H2 molecules under ambient conditions. The evaluated reversible storage capacity is 6.1 wt%. Our results demonstrate that the new Ti-decorated B40 fullerene is a promising hydrogen storage material with high capacity.

  11. Lightweight Intermetallics with Laves Structures as Potential Hydrogen Storage Materials

    NASA Astrophysics Data System (ADS)

    Billet, Beau Austin

    Hydrogen storage was identified by the US Department of Energy as a "grand challenge" for the implementation of hydrogen-powered fuel cell vehicles for reduced CO2 emissions from transportation vehicles. None of the hydrogen storage options currently developed can satisfy the high gravimetric, volumetric and system design requirements. Intermetallic compounds with Laves structures in the formula of AB2 have long been known to store hydrogen in their interstitial sites to serve as reversible hydrogen storage materials (A and B are metallic elements). They have the potential to be hydrided to a maximum of ~ AB2H6 due to the impeding H-H interactions at neighboring interstitial sites. To achieve the highest weight percent of hydrogen storage in AB2H6, the lowest combined atomic weight of AB2 is required. The CaLi2 compound is the lightest known Laves phase, but it could not maintain its Laves structure when it was hydrided. Existing work of Akiba's group showed that a ternary Laves phase CaLi1.8Mg0.2 could be hydrided to form a hydrogenated Laves phase, but the absorbed hydrogen could not be released for reversible storage. Substitutions (Ca,X)Li1.8Mg0.2 are explored in the present study to see whether heavier elements [X = Sr, Ba and Ce] in small quantities can make the lightweight Laves compounds reversibly store hydrogen. Induction melting was successful in obtaining the desired Laves phases. The base system, CaLi1.8Mg0.2, formed a single phase, consistent with the literature result. Both Ca0.9Ba0.1Li 1.8Mg0.2 and Ca0.9Ce0.1Li1.8Mg 0.2 also formed a single-phase C14 Laves, whereas both Ca0.9Sr 0.1Li1.8Mg0.2 and Ca0.8Sr0.2Li 1.8Mg0.2 formed two seperature Laves phases with the same crystal structure, indicating a phase separation. The Ca0.8Ba 0.2Li1.8Mg0.2 composition completely lost the Laves-phase structure, forming CaLi2, CaMg2, BaLi 4 and Ca. All compounds tested at temperatures from 25 °C to 150 °C show the characteristic "plateau" behavior in the pressure

  12. MXene: a new family of promising hydrogen storage medium.

    PubMed

    Hu, Qianku; Sun, Dandan; Wu, Qinghua; Wang, Haiyan; Wang, Libo; Liu, Baozhong; Zhou, Aiguo; He, Julong

    2013-12-27

    Searching for reversible hydrogen storage materials operated under ambient conditions is a big challenge for material scientists and chemists. In this work, using density functional calculations, we systematically investigated the hydrogen storage properties of the two-dimensional (2D) Ti2C phase, which is a representative of the recently synthesized MXene materials ( ACS Nano 2012 , 6 , 1322 ). As a constituent element of 2D Ti2C phase, the Ti atoms are fastened tightly by the strong Ti-C covalent bonds, and thus the long-standing clustering problem of transition metal does not exist. Combining with the calculated binding energy of 0.272 eV, ab initio molecular dynamic simulations confirmed the hydrogen molecules (3.4 wt % hydrogen storage capacity) bound by Kubas-type interaction can be adsorbed and released reversibly under ambient conditions. Meanwhile, the hydrogen storage properties of the other two MXene phases (Sc2C and V2C) were also evaluated, and the results were similar to those of Ti2C. Therefore, the MXene family including more than 20 members was expected to be a good candidate for reversible hydrogen storage materials under ambient conditions.

  13. Effect of stoichiometry and Cu-substitution on the phase structure and hydrogen storage properties of Ml-Mg-Ni-based alloys

    NASA Astrophysics Data System (ADS)

    Li, Yuan; Tao, Yang; Huo, Quan

    2015-01-01

    To improve the electrochemical properties of rare-earth-Mg-Ni-based hydrogen storage alloys, the effects of stoichiometry and Cu-substitution on the phase structure and thermodynamic properties of the alloys were studied. Nonsubstituted Ml0.80Mg0.20(Ni2.90Co0.50-Mn0.30Al0.30) x ( x = 0.68, 0.70, 0.72, 0.74, 0.76) alloys and Cu-substituted Ml0.80Mg0.20(Ni2.90Co0.50- y Cu y Mn0.30Al0.30)0.70 ( y = 0, 0.10, 0.30, 0.50) alloys were prepared by induction melting. Phase structure analysis shows that the nonsubstituted alloys consist of a LaNi5 phase, a LaNi3 phase, and a minor La2Ni7 phase; in addition, in the case of Cu-substitution, the Nd2Ni7 phase appears and the LaNi3 phase vanishes. Thermodynamic tests show that the enthalpy change in the dehydriding process decreases, indicating that hydride stability decreases with increasing stoichiometry and increasing Cu content. The maximum discharge capacity, kinetic properties, and cycling stability of the alloy electrodes all increase and then decrease with increasing stoichiometry or increasing Cu content. Furthermore, Cu substitution for Co ameliorates the discharge capacity, kinetics, and cycling stability of the alloy electrodes.

  14. Long-term storage of nickel-hydrogen cells

    NASA Technical Reports Server (NTRS)

    Vaidyanathan, Hari

    1987-01-01

    Representative samples of nickel hydrogen cells for the INTELSAT program were used to evaluate the effects of prolonged storage under passive conditions such as open circuit discharged at 0 C, room temperature, and -20 C, and under quasidynamic conditions such as top-off charge and trickle charge. Cell capacity declines when cells are stored open-circuit discharged at room temperature, and a second plateau occurs in the discharge curve. Capacity loss was 47 percent for a cell with hydrogen precharge and 24.5 percent for one with no hydrogen precharge. Capacity recovery was observed following top-off charge storage of cells which had exhibited faded capacity as a result of passive storage at room temperature. Cells stored either at -20 C or on trickle charge maintained their capacity. At 0 C storage, the capacity of all three cells under tests was greater than 55 Ah (which exceeds the required minimum of 44 Ah) after 7 months.

  15. Iron titanium manganase alloy hydrogen storage

    DOEpatents

    Reilly, James J.; Wiswall, Jr., Richard H.

    1979-01-01

    A three component alloy capable of reversible sorption of hydrogen having the chemical formula TiFe.sub.1-x Mn.sub.x where x is in the range of about 0.02 to 0.5 and the method of storing hydrogen using said alloy.

  16. Reversible Hydrogen Storage Materials – Structure, Chemistry, and Electronic Structure

    SciTech Connect

    Robertson, Ian M.; Johnson, Duane D.

    2014-06-21

    To understand the processes involved in the uptake and release of hydrogen from candidate light-weight metal hydride storage systems, a combination of materials characterization techniques and first principle calculation methods have been employed. In addition to conventional microstructural characterization in the transmission electron microscope, which provides projected information about the through thickness microstructure, electron tomography methods were employed to determine the three-dimensional spatial distribution of catalyst species for select systems both before and after dehydrogenation. Catalyst species identification as well as compositional analysis of the storage material before and after hydrogen charging and discharging was performed using a combination of energy dispersive spectroscopy, EDS, and electron energy loss spectroscopy, EELS. The characterization effort was coupled with first-principles, electronic-structure and thermodynamic techniques to predict and assess meta-stable and stable phases, reaction pathways, and thermodynamic and kinetic barriers. Systems studied included:NaAlH4, CaH2/CaB6 and Ca(BH4)2, MgH2/MgB2, Ni-Catalyzed Magnesium Hydride, TiH2-Catalyzed Magnesium Hydride, LiBH4, Aluminum-based systems and Aluminum

  17. Hydrogen storage performance of functionalized hexagonal boron nitride for fuel cell applications

    NASA Astrophysics Data System (ADS)

    Muthu, R. Naresh; Rajashabala, S.; Kannan, R.

    2017-05-01

    Developing light weight, safe, efficient and compact hydrogen storage medium are still the major concerns for the blooming of hydrogen based energy economy. In the present article, activated hexagonal boron nitride (ABN) and ABN functionalized with lithium borohydride (ABN-LiBH4) nanocomposite based hydrogen storage medium are synthesized. where a facile solvent-assistant technique was adopted for the preparation of ABN-LiBH4 nanocomposite. The prepared hydrogen storage medium was subjected to various characterization techniques such as XRD, FTIR, SEM, EDX, CHNS - elemental analysis and TGA. Sievert's-like hydrogenation setup has been utilized for hydrogenation studies. It is noticed that the ABN-LiBH4 nanocomposite exhibits an attractive high gravimetric density of 1.67 wt% at 100 °C than pristine ABN. Moreover the stored hydrogen is released in the temperature range of 115 - 150 °C and possesses an average binding energy of 0.31 eV. These results indicate that the prepared ABN-LiBH4 nanocomposite paves a way to potential solid state hydrogen storage medium towards fuel cell technology as per the targets set by US Department of Energy (DOE).

  18. Metallacarboranes: Towards promising hydrogen storage metal organic framework

    NASA Astrophysics Data System (ADS)

    Singh, Abhishek; Sadrzadeh, Arta; Yakobson, Boris

    2011-03-01

    Using first principles calculations we show the high hydrogen storage capacity of metallacarboranes, where the transition metal (TM) atoms bind hydrogen via Kubas interaction. The average binding energy of ~ 0.3 eV/H favorably lies within the reversible adsorption range The Sc and Ti are found to be the optimum metal atoms maximizing the number of stored H2 molecules. Depending upon the structure, metallacarboranes can adsorb up to 8 wt% of hydrogen, which exceeds DOE goal for 2015. Being integral part of the cage, TMs do not suffer from the aggregation problem. Furthermore, the presence of carbon atom in the cages permits linking the metallacarboranes to form metal organic frameworks (MOF), thus able to adsorb hydrogen via Kubas interaction, in addition to van der Waals physisorption. A. K. Singh, A. Sadrzadeh, and B. I. Yakobson, Metallacarboranes: Toward Promising Hydrogen Storage Metal Organic Frameworks, JACS 132,14126 (2010).

  19. Nanopores of carbon nanotubes as practical hydrogen storage media

    SciTech Connect

    Han, Sang Soo; Kim, Hyun Seok; Han, Kyu Sung; Lee, Jai Young; Lee, Hyuck Mo; Kang, Jeung Ku; Woo, Seong Ihl; Duin, Adri C.T. van; Goddard, William A. III

    2005-11-21

    We report on hydrogen desorption mechanisms in the nanopores of multiwalled carbon nanotubes (MWCNTs). The as-grown MWCNTs show continuous walls that do not provide sites for hydrogen storage under ambient conditions. However, after treating the nanotubes with oxygen plasma to create nanopores in the MWCNTs, we observed the appearance of a new hydrogen desorption peak in the 300-350 K range. Furthermore, the calculations of density functional theory and molecular dynamics simulations confirmed that this peak could be attributed to the hydrogen that is physically adsorbed inside nanopores whose diameter is approximately 1 nm. Thus, we demonstrated that 1 nm nanopores in MWCNTs offer a promising route to hydrogen storage media for onboard practical applications.

  20. Hydrogen storage and delivery: the carbon dioxide - formic acid couple.

    PubMed

    Laurenczy, Gábor

    2011-01-01

    Carbon dioxide and the carbonates, the available natural C1 sources, can be easily hydrogenated into formic acid and formates in water; the rate of this reduction strongly depends on the pH of the solution. This reaction is catalysed by ruthenium(II) pre-catalyst complexes with a large variety of water-soluble phosphine ligands; high conversions and turnover numbers have been realised. Although ruthenium(II) is predominant in these reactions, the iron(II) - tris[(2-diphenylphosphino)-ethyl]phosphine (PP3) complex is also active, showing a new perspective to use abundant and inexpensive iron-based compounds in the CO2 reduction. In the catalytic hydrogenation cycles the in situ formed metal hydride complexes play a key role, their structures with several other intermediates have been proven by multinuclear NMR spectroscopy. In the other hand safe and convenient hydrogen storage and supply is the fundamental question for the further development of the hydrogen economy; and carbon dioxide has been recognised to be a viable H2 vector. Formic acid--containing 4.4 weight % of H2, that is 53 g hydrogen per litre--is suitable for H2 storage; we have shown that in aqueous solutions it can be selectively decomposed into CO-free (CO < 10 ppm) CO2 and H2. The reaction takes place under mild experimental conditions and it is able to generate high pressure H2 (up to 600 bar). The cleavage of HCOOH is catalysed by several hydrophilic Ru(II) phosphine complexes (meta-trisulfonated triphenylphosphine, mTPPTS, being the most efficient one), either in homogeneous systems or as immobilised catalysts. We have also shown that the iron(II)--hydrido tris[(2-diphenylphosphino)ethyl]phosphine complex catalyses with an exceptionally high rate and efficiency (turnover frequency, TOF = 9425 h(-1)mol(-1); turnover number, TON = 92400) the formic acid cleavage, in environmentally friendly propylene carbonate solution, opening the way to use cheap, non-noble metal based catalysts for this

  1. Atomic hydrogen storage method and apparatus

    NASA Technical Reports Server (NTRS)

    Woollam, J. A. (Inventor)

    1978-01-01

    Atomic hydrogen, for use as a fuel or as an explosive, is stored in the presence of a strong magnetic field in exfoliated layered compounds such as molybdenum disulfide or an elemental layer material such as graphite. The compound is maintained at liquid helium temperatures and the atomic hydrogen is collected on the surfaces of the layered compound which are exposed during delamination (exfoliation). The strong magnetic field and the low temperature combine to prevent the atoms of hydrogen from recombining to form molecules.

  2. Recommended Best Practices for the Characterization of Storage Properties of Hydrogen Storage Materials

    SciTech Connect

    2010-03-01

    This is a reference guide to common methodologies and protocols for measuring critical performance properties of advanced hydrogen storage materials. It helps users to communicate clearly the relevant performance properties of new materials as they are discovered and tested.

  3. Hydrogen storage in insulated pressure vessels

    SciTech Connect

    Aceves, S.M.; Garcia-Villazana, O.

    1998-08-01

    Insulated pressure vessels are cryogenic-capable pressure vessels that can be fueled with liquid hydrogen (LH{sub 2}) or ambient-temperature compressed hydrogen (CH{sub 2}). Insulated pressure vessels offer the advantages of liquid hydrogen tanks (low weight and volume), with reduced disadvantages (lower energy requirement for hydrogen liquefaction and reduced evaporative losses). This paper shows an evaluation of the applicability of the insulated pressure vessels for light-duty vehicles. The paper shows an evaluation of evaporative losses and insulation requirements and a description of the current analysis and experimental plans for testing insulated pressure vessels. The results show significant advantages to the use of insulated pressure vessels for light-duty vehicles.

  4. First-principles study of hydrogen storage on Li12F12 nano-cage

    NASA Astrophysics Data System (ADS)

    Zhang, Yafei; Cheng, Xinlu

    2017-03-01

    We use the first-principles calculation based on density functional theory (DFT) to investigate the hydrogen storage on Li12F12 nano-cage. Our result indicates the largest hydrogen gravimetric density is 7.14 wt% and this is higher than the 2017 target from the US department of energy (DOE). Meanwhile, the average adsorption energy is -0.161 eV/H2, which is desirable for absorbing and desorbing H2 molecules at near ambient conditions. These findings will have important implications on designing hydrogen storage materials in the future.

  5. Use of reversible hydrides for hydrogen storage

    NASA Technical Reports Server (NTRS)

    Darriet, B.; Pezat, M.; Hagenmuller, P.

    1980-01-01

    The addition of metals or alloys whose hydrides have a high dissociation pressure allows a considerable increase in the hydrogenation rate of magnesium. The influence of temperature and hydrogen pressure on the reaction rate were studied. Results concerning the hydriding of magnesium rich alloys such as Mg2Ca, La2Mg17 and CeMg12 are presented. The hydriding mechanism of La2Mg17 and CeMg12 alloys is given.

  6. Activatino of Erbium Films for Hydrogen Storage

    SciTech Connect

    M Brumbach; j Ohlhausen; K Zavadil; C Snow; J Woicik

    2011-12-31

    Hydriding of metals can be routinely performed at high temperature in a rich hydrogen atmosphere. Prior to the hydrogen loading process, a thermal activation procedure is required to promote facile hydrogen sorption into the metal. Despite the wide spread utilization of this activation procedure, little is known about the chemical and electronic changes that occur during activation and how this thermal pretreatment leads to increased rates of hydrogen uptake. This study utilized variable kinetic energy X-ray photoelectron spectroscopy to interrogate the changes during in situ thermal annealing of erbium films, with results confirmed by time-of-flight secondary ion mass spectrometry and low energy ion scattering. Activation can be identified by a large increase in photoemission between the valence band edge and the Fermi level and appears to occur over a two stage process. The first stage involves desorption of contaminants and recrystallization of the oxide, initially impeding hydrogen loading. Further heating overcomes the first stage and leads to degradation of the passive surface oxide leading to a bulk film more accessible for hydrogen loading.

  7. LANL Virtual Center for Chemical Hydrogen Storage: Chemical Hydrogen Storage Using Ultra-high Surface Area Main Group Materials

    SciTech Connect

    Susan M. Kauzlarich; Phillip P. Power; Doinita Neiner; Alex Pickering; Eric Rivard; Bobby Ellis, T. M.; Atkins, A. Merrill; R. Wolf; Julia Wang

    2010-09-05

    The focus of the project was to design and synthesize light element compounds and nanomaterials that will reversibly store molecular hydrogen for hydrogen storage materials. The primary targets investigated during the last year were amine and hydrogen terminated silicon (Si) nanoparticles, Si alloyed with lighter elements (carbon (C) and boron (B)) and boron nanoparticles. The large surface area of nanoparticles should facilitate a favorable weight to volume ratio, while the low molecular weight elements such as B, nitrogen (N), and Si exist in a variety of inexpensive and readily available precursors. Furthermore, small NPs of Si are nontoxic and non-corrosive. Insights gained from these studies will be applied toward the design and synthesis of hydrogen storage materials that meet the DOE 2010 hydrogen storage targets: cost, hydrogen capacity and reversibility. Two primary routes were explored for the production of nanoparticles smaller than 10 nm in diameter. The first was the reduction of the elemental halides to achieve nanomaterials with chloride surface termination that could subsequently be replaced with amine or hydrogen. The second was the reaction of alkali metal Si or Si alloys with ammonium halides to produce hydrogen capped nanomaterials. These materials were characterized via X-ray powder diffraction, TEM, FTIR, TG/DSC, and NMR spectroscopy.

  8. Davisson-Germer Prize Talk: Hydrogen storage in nanoporous materials

    NASA Astrophysics Data System (ADS)

    Chabal, Yves

    2009-03-01

    To develop a hydrogen-based energy technology, several classes of materials are being considered to achieve the DOE targets for gravimetric and volumetric hydrogen densities for hydrogen storage, including liquids (e.g. ammonium borohydrides), clathrate structures, complex metal hydrides, nanostructured (e.g. carbon) an nanoporous materials. Fundamental studies are necessary to determine the ultimate hydrogen capacity of each system. Nanoporous Metal-organic Framework (MOF) materials are promising candidates for hydrogen storage because the chemical nature and size of their unit cell can be tailored to weakly attract and incorporate H2 molecules, with good volumetric and mass density. In this talk, we consider the structure M2(BDC)2(TED), where M is a metal atom (Zn, Ni, Cu), BDC is benzenedicarboxylate and TED triethylenediamine, to determine the location and interaction of H2 molecules within the MOF. These compounds are isostructural and crystallize in the tetragonal phase (space group P4/ncc), they construct 3D porous structures with relatively large pore size (˜7-8 A ), pore volume (˜0.63-0.84 cc/g) and BET surface area (˜1500-1900 m^2/g). At high pressures (300-800 psi), the perturbation of the H-H stretching mode can be measured with IR absorption spectroscopy, showing a 35 cm-1 redshift from the unperturbed ortho (4155 cm-1 ) and para (4161 cm-1 ) frequencies. Using a newly developed non empirical van der Waals DFT method vdW-DFT),ootnotetextJ.Y. Lee, D.H. Olson, L. Pan, T.J. Emge, J. Li, Adv. Func. Mater. 17, 1255 (2007) it can be shown that the locus of the deepest H2 binding positions lies within to types of narrow channels. The energies of the most stable binding sites, as well as the number of such binding sites, are consistent with the values obtained from experimental adsorption isotherms, and heat of adsorption) data.ootnotetextM. Dion, H. Ryberg, E. Schroder, D. C. Langreth, B.I. Lundqvist, Phys. Rev. Lett. 92, 246401 (2004). Importantly, the

  9. Hydrogen storage and phase transformations in Mg-Pd nanoparticles

    NASA Astrophysics Data System (ADS)

    Callini, E.; Pasquini, L.; Rude, L. H.; Nielsen, T. K.; Jensen, T. R.; Bonetti, E.

    2010-10-01

    Microstructure refinement and synergic coupling among different phases are currently explored strategies to improve the hydrogen storage properties of traditional materials. In this work, we apply a combination of these methods and synthesize Mg-Pd composite nanoparticles by inert gas condensation of Mg vapors followed by vacuum evaporation of Pd clusters. Irreversible formation of the Mg6Pd intermetallic phase takes place upon vacuum annealing, resulting in Mg/Mg6Pd composite nanoparticles. Their hydrogen storage properties are investigated and connected to the undergoing phase transformations by gas-volumetric techniques and in situ synchrotron radiation powder x-ray diffraction. Mg6Pd transforms reversibly into different Mg-Pd intermetallic compounds upon hydrogen absorption, depending on temperature and pressure. In particular, at 573 K and 1 MPa hydrogen pressure, the metal-hydride transition leads to the formation of Mg3Pd and Mg5Pd2 phases. By increasing the pressure to 5 MPa, the Pd-richer MgPd intermetallic is obtained. Upon hydrogen desorption, the Mg6Pd phase is reversibly recovered. These phase transformations result in a specific hydrogen storage capacity associated with Mg-Pd intermetallics, which attain the maximum value of 3.96 wt % for MgPd and influence both the thermodynamics and kinetics of hydrogen sorption in the composite nanoparticles.

  10. Chemical grafting of Co9S8 onto C60 for hydrogen spillover and storage.

    PubMed

    Han, Lu; Qin, Wei; Zhou, Jia; Jian, Jiahuang; Lu, Songtao; Wu, Xiaohong; Fan, Guohua; Gao, Peng; Liu, Boyu

    2017-04-20

    Metal modified C60 is considered to be a potential hydrogen storage medium due to its high theoretical capacity. Research interest is growing in various hybrid inorganic compounds-C60. While the design and synthesis of a novel hybrid inorganic compound-C60 is difficult to attain, it has been theorized that the atomic hydrogen could transfer from the inorganic compound to the adjacent C60 surfaces via spillover and surface diffusion. Here, as a proof of concept experiment, we graft Co9S8 onto C60via a facile high energy ball milling process. The Raman, XPS, XRD, TEM, HTEM and EELS measurements have been conducted to evaluate the composition and structure of the pizza-like hybrid material. In addition, the electrochemical measurements and calculated results demonstrate that the chemical "bridges" (C-S bonds) between these two materials enhance the binding strength and, hence, facilitate the hydriding reaction of C60 during the hydrogen storage process. As a result, an increased hydrogen storage capacity of 4.03 wt% is achieved, along with a favorable cycling stability of ∼80% after 50 cycles. Excluding the direct hydrogen storage contribution from Co9S8 in the hybrid paper, the hydrogen storage ability of C60 was enhanced by 5.9× through the hydriding reaction caused by the Co9S8 modifier. Based on these experimental measurements and theoretical calculations, the unique chemical structure reported here could potentially inspire other C60-based advanced hybrids.

  11. Storage and production of hydrogen for fuel cell applications

    NASA Astrophysics Data System (ADS)

    Aiello, Rita

    The increased utilization of proton-exchange membrane (PEM) fuel cells as an alternative to internal combustion engines is expected to increase the demand for hydrogen, which is used as the energy source in these systems. The objective of this work is to develop and test new methods for the storage and production of hydrogen for fuel cells. Six ligand-stabilized hydrides were synthesized and tested as hydrogen storage media for use in portable fuel cells. These novel compounds are more stable than classical hydrides (e.g., NaBH4, LiAlH4) and react to release hydrogen less exothermically upon hydrolysis with water. Three of the compounds produced hydrogen in high yield (88 to 100 percent of the theoretical) and at significantly lower temperatures than those required for the hydrolysis of NaBH4 and LiAlH4. However, a large excess of water and acid were required to completely wet the hydride and keep the pH of the reaction medium neutral. The hydrolysis of the classical hydrides with steam can overcome these limitations. This reaction was studied in a flow reactor and the results indicate that classical hydrides can be hydrolyzed with steam in high yields at low temperatures (110 to 123°C) and in the absence of acid. Although excess steam was required, the pH of the condensed steam was neutral. Consequently, steam could be recycled back to the reactor. Production of hydrogen for large-scale transportation fuel cells is primarily achieved via the steam reforming, partial oxidation or autothermal reforming of natural gas or the steam reforming of methanol. However, in all of these processes CO is a by-product that must be subsequently removed because the Pt-based electrocatalyst used in the fuel cells is poisoned by its presence. The direct cracking of methane over a Ni/SiO2 catalyst can produce CO-free hydrogen. In addition to hydrogen, filamentous carbon is also produced. This material accumulates on the catalyst and eventually deactivates it. The Ni/SiO2 catalyst

  12. Evaluation of insulated pressure vessels for cryogenic hydrogen storage

    SciTech Connect

    Aceves, S M; Garcia-Villazana, O; Martinez-Frias, J

    1999-03-01

    This paper presents an analytical and experimental evaluation of the applicability of insulated pressure vessels for hydrogen-fueled light-duty vehicles. Insulated pressure vessels are cryogenic-capable pressure vessels that can be fueled with liquid hydrogen (LH?) or ambient-temperature compressed hydrogen (CH2). Insulated pressure vessels offer the advantages of liquid hydrogen tanks (low weight and volume), with reduced disadvantages (lower energy requirement for hydrogen liquefaction and reduced evaporative losses). The purpose of this work is to verify that commercially available aluminum-lined, fiber- wrapped vessels can be used for cryogenic hydrogen storage. The paper reports on previous and ongoing tests and analyses that have the purpose of improving the system design and assure its safety.

  13. High-performances carbonaceous adsorbents for hydrogen storage

    NASA Astrophysics Data System (ADS)

    Zhao, Weigang; Fierro, Vanessa; Aylon, E.; Izquierdo, M. T.; Celzard, Alain

    2013-03-01

    Activated carbons (ACs) with controlled microporosity have been prepared and their H2 storage performances have been tested in a gravimetric device. Such adsorbents are natural Chinese anthracites chemically activated with alkaline hydroxides, NaOH or KOH. Outstanding total storage capacities of hydrogen, as high as 6.6wt.% equivalent to excess capacity of 6.2 wt.%, have been obtained at 4MPa for some of these adsorbents. These values of hydrogen adsorption are among the best, if not the highest, ever published so far in the open literature. They are well above those of some commercial materials, e.g. Maxsorb-3, considered as a reference of high-performance adsorbent for hydrogen adsorption. Such exceptional storage capacities may be ascribed to a higher volume of micropores (< 2nm).

  14. Lunar-derived titanium alloys for hydrogen storage

    NASA Technical Reports Server (NTRS)

    Love, S.; Hertzberg, A.; Woodcock, G.

    1992-01-01

    Hydrogen gas, which plays an important role in many projected lunar power systems and industrial processes, can be stored in metallic titanium and in certain titanium alloys as an interstitial hydride compound. Storing and retrieving hydrogen with titanium-iron alloy requires substantially less energy investment than storage by liquefaction. Metal hydride storage systems can be designed to operate at a wide range of temperatures and pressures. A few such systems have been developed for terrestrial applications. A drawback of metal hydride storage for lunar applications is the system's large mass per mole of hydrogen stored, which rules out transporting it from earth. The transportation problem can be solved by using native lunar materials, which are rich in titanium and iron.

  15. Lunar-derived titanium alloys for hydrogen storage

    NASA Technical Reports Server (NTRS)

    Love, S.; Hertzberg, A.; Woodcock, G.

    1992-01-01

    Hydrogen gas, which plays an important role in many projected lunar power systems and industrial processes, can be stored in metallic titanium and in certain titanium alloys as an interstitial hydride compound. Storing and retrieving hydrogen with titanium-iron alloy requires substantially less energy investment than storage by liquefaction. Metal hydride storage systems can be designed to operate at a wide range of temperatures and pressures. A few such systems have been developed for terrestrial applications. A drawback of metal hydride storage for lunar applications is the system's large mass per mole of hydrogen stored, which rules out transporting it from earth. The transportation problem can be solved by using native lunar materials, which are rich in titanium and iron.

  16. Carbon nanoscrolls: a promising material for hydrogen storage.

    PubMed

    Mpourmpakis, Giannis; Tylianakis, Emmanuel; Froudakis, George E

    2007-07-01

    A multiscale theoretical approach was used for the investigation of hydrogen storage in the recently synthesized carbon nanoscrolls. First, ab initio calculations at the density functional level of theory (DFT) were performed in order to (a) calculate the binding energy of H2 molecules at the walls of nanoscrolls and (b) fit the parameters of the interatomic potential used in Monte Carlo simulations. Second, classical Monte Carlo simulations were performed for estimating the H2 storage capacity of "experimental size" nanoscrolls containing thousands of atoms. Our results show that pure carbon nanoscrolls cannot accumulate hydrogen because the interlayer distance is too small. However, an opening of the spiral structure to approximately 7 A followed by alkali doping can make them very promising materials for hydrogen storage application, reaching 3 wt % at ambient temperature and pressure.

  17. 14 CFR 420.66 - Separation distance requirements for storage of hydrogen peroxide, hydrazine, and liquid hydrogen...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... storage of hydrogen peroxide, hydrazine, and liquid hydrogen and any incompatible energetic liquids stored... Responsibilities of a Licensee § 420.66 Separation distance requirements for storage of hydrogen peroxide... section for each explosive hazard facility storing: (1) Hydrogen peroxide in concentrations of greater...

  18. 14 CFR 420.66 - Separation distance requirements for storage of hydrogen peroxide, hydrazine, and liquid hydrogen...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... storage of hydrogen peroxide, hydrazine, and liquid hydrogen and any incompatible energetic liquids stored... Responsibilities of a Licensee § 420.66 Separation distance requirements for storage of hydrogen peroxide... section for each explosive hazard facility storing: (1) Hydrogen peroxide in concentrations of greater...

  19. Effects of Ti-Based Additives on the Hydrogen Storage Properties of a L i B H 4 / C a H 2 Destabilized System

    DOE PAGES

    Yang, Hongwei; Ibikunle, Adeola; Goudy, Andrew J.

    2010-01-01

    Tmore » he hydrogen storage properties of a destabilized LiBH 4 / CaH 2 system ball-milled with TiCl 3 , TiF 3 , and TiO 2 additives have been investigated. It is found that the system with TiCl 3 additive has a lower dehydrogenation temperature than the ones with other additives. Further study shows that a higher amount of TiCl 3 is more effective in reducing the desorption temperature of the LiBH 4 / CaH 2 system, since it leads to a lower activation energy of dehydrogenation.he activations energies for mixtures containing 4, 10, and 25 mol% of TiCl 3 are 141, 126, and 110 kJ/mol, respectively. However, the benefits of higher amounts of TiCl 3 are offset by a larger reduction in hydrogen capacity of the mixtures.« less

  20. Thermodynamically Tuned Nanophase Materials for reversible Hydrogen storage

    SciTech Connect

    Ping Liu; John J. Vajo

    2010-02-28

    This program was devoted to significantly extending the limits of hydrogen storage technology for practical transportation applications. To meet the hydrogen capacity goals set forth by the DOE, solid-state materials consisting of light elements were developed. Many light element compounds are known that have high capacities. However, most of these materials are thermodynamically too stable, and they release and store hydrogen much too slowly for practical use. In this project we developed new light element chemical systems that have high hydrogen capacities while also having suitable thermodynamic properties. In addition, we developed methods for increasing the rates of hydrogen exchange in these new materials. The program has significantly advanced (1) the application of combined hydride systems for tuning thermodynamic properties and (2) the use of nanoengineering for improving hydrogen exchange. For example, we found that our strategy for thermodynamic tuning allows both entropy and enthalpy to be favorably adjusted. In addition, we demonstrated that using porous supports as scaffolds to confine hydride materials to nanoscale dimensions could improve rates of hydrogen exchange by > 50x. Although a hydrogen storage material meeting the requirements for commercial development was not achieved, this program has provided foundation and direction for future efforts. More broadly, nanoconfinment using scaffolds has application in other energy storage technologies including batteries and supercapacitors. The overall goal of this program was to develop a safe and cost-effective nanostructured light-element hydride material that overcomes the thermodynamic and kinetic barriers to hydrogen reaction and diffusion in current materials and thereby achieve > 6 weight percent hydrogen capacity at temperatures and equilibrium pressures consistent with DOE target values.

  1. Energy storage possibilities of atomic hydrogen

    NASA Technical Reports Server (NTRS)

    Etters, R. D.; Dugan, J. V., Jr.; Palmer, R.

    1976-01-01

    Several recent experiments designed to produce and store macroscopic quantities of atomic hydrogen are discussed. The bulk, ground state properties of atomic hydrogen, deuterium, and tritium systems are calculated assuming that all pair interactions occur via the atomic triplet potential. The conditions required to obtain this system, including inhibition of recombination through the energetically favorable singlet interaction, are discussed. The internal energy, pressure, and compressibility are calculated applying the Monte Carlo technique with a quantum mechanical variational wavefunction. The system studied consisted of 32 atoms in a box with periodic boundary conditions. Results show that atomic triplet hydrogen and deuterium remain gaseous at 0 K; i.e., the internal energy is positive at all molar volumes considered.

  2. Energy storage possibilities of atomic hydrogen

    NASA Technical Reports Server (NTRS)

    Etters, R. D.; Dugan, J. V., Jr.; Palmer, R.

    1976-01-01

    Several recent experiments designed to produce and store macroscopic quantities of atomic hydrogen are discussed. The bulk, ground state properties of atomic hydrogen, deuterium, and tritium systems are calculated assuming that all pair interactions occur via the atomic triplet potential. The conditions required to obtain this system, including inhibition of recombination through the energetically favorable singlet interaction, are discussed. The internal energy, pressure, and compressibility are calculated applying the Monte Carlo technique with a quantum mechanical variational wavefunction. The system studied consisted of 32 atoms in a box with periodic boundary conditions. Results show that atomic triplet hydrogen and deuterium remain gaseous at 0 K; i.e., the internal energy is positive at all molar volumes considered.

  3. Improving the hydrogen storage properties of metal-organic framework by functionalization.

    PubMed

    Xia, Liangzhi; Liu, Qing; Wang, Fengling; Lu, Jinming

    2016-10-01

    Based on the structure of MOF-808, different substituents were introduced to replace hydrogen atom on the phenyl ring of MOF-808. The GCMC method was used to study the effect of functional groups on the hydrogen storage properties of MOF-808-X (X = -OH, -NO2, -CH3, -CN, -I). The H2 uptakes and isosteric heat of adsorption were simulated at 77 K. The results indicate that all these substituents have favorable impact on the hydrogen storage capacity, and -CN is found to be the most promising substituent to improve H2 uptake. These results may be helpful for the design of MOFs with higher hydrogen storage capacity. Graphical abstract Atomistic structures of MOFs. (a) The structures of MOF-808-X. (b) Model of organic linker. Atom color scheme: C, gray; H, white; O, red; X, palegreen (X = -OH, -NO2, -CH3, -CN, -I).

  4. FINAL REPORT: Room Temperature Hydrogen Storage in Nano-Confined Liquids

    SciTech Connect

    VAJO, JOHN

    2014-06-12

    DOE continues to seek solid-state hydrogen storage materials with hydrogen densities of ≥6 wt% and ≥50 g/L that can deliver hydrogen and be recharged at room temperature and moderate pressures enabling widespread use in transportation applications. Meanwhile, development including vehicle engineering and delivery infrastructure continues for compressed-gas hydrogen storage systems. Although compressed gas storage avoids the materials-based issues associated with solid-state storage, achieving acceptable volumetric densities has been a persistent challenge. This project examined the possibility of developing storage materials that would be compatible with compressed gas storage technology based on enhanced hydrogen solubility in nano-confined liquid solvents. These materials would store hydrogen in molecular form eliminating many limitations of current solid-state materials while increasing the volumetric capacity of compressed hydrogen storage vessels. Experimental methods were developed to study hydrogen solubility in nano-confined liquids. These methods included 1) fabrication of composites comprised of volatile liquid solvents for hydrogen confined within the nano-sized pore volume of nanoporous scaffolds and 2) measuring the hydrogen uptake capacity of these composites without altering the composite composition. The hydrogen storage capacities of these nano-confined solvent/scaffold composites were compared with bulk solvents and with empty scaffolds. The solvents and scaffolds were varied to optimize the enhancement in hydrogen solubility that accompanies confinement of the solvent. In addition, computational simulations were performed to study the molecular-scale structure of liquid solvent when confined within an atomically realistic nano-sized pore of a model scaffold. Confined solvent was compared with similar simulations of bulk solvent. The results from the simulations were used to formulate a mechanism for the enhanced solubility and to guide the

  5. Dehydrogenation kinetics, reversibility, and reaction mechanisms of reversible hydrogen storage material based on nanoconfined MgH2-NaAlH4

    NASA Astrophysics Data System (ADS)

    Plerdsranoy, Praphatsorn; Meethom, Sukanya; Utke, Rapee

    2015-12-01

    Studies of dehydrogenation kinetics, reversibility, and reaction mechanisms during de/rehydrogenation of nanoconfined MgH2-NaAlH4 into carbon aerogel scaffold (CAS) for reversible hydrogen storage material are for the first time proposed. Two different MgH2:NaAlH4 molar ratios (1:1 and 2:1) of hydride composite are melt infiltrated into CAS under 1:1 (CAS:hydride composite) weight ratio. Successful nanoconfinement is confirmed by N2 adsorption-desorption. Multiple-step dehydrogenation of milled samples is reduced to two-step reaction due to nanoconfinement. Peak temperatures corresponding to main dehydrogenation of nanoconfined samples significantly reduce as compared with those of milled samples, i.e., ∆T=up to 50 and 34 °C for nanoconfined sample with 1:1 and 2:1 (MgH2:NaAlH4) molar ratios, respectively. Hydrogen content released (the 1st cycle) and reproduced (the 2nd, 3rd, and 4th cycles) of nanoconfined samples enhance up to 80% and 68% with respect to theoretical hydrogen storage capacity, respectively, while those of milled samples are 71% and 38%, respectively. Remarkable hydrogen content reproduced after nanoconfinement is due to the fact that metallic Al obtained after dehydrogenation (T=300 °C under vacuum) of nanoconfined samples prefer to react with MgH2 and produces Al12Mg17, favorable for reversibility of MgH2-NaAlH4 system, whereas that of milled samples stays in the form of unreacted Al under the same temperature and pressure condition.

  6. Numerical simulation of hydrogen desorption from high-density metal hydride hydrogen storage vessels

    NASA Astrophysics Data System (ADS)

    Sang-Kun, O.; Yi, Kyung-Woo; Cho, Sung-Wook

    2017-07-01

    Metal hydride (MH) alloys are a promising type of material in hydrogen storage applications, allowing for low-pressure, high-density storage. However, while many studies are being performed on enhancing the hydrogen storage properties of such alloys, there has been little research on large-scale storage vessels which make use of the alloys. In particular, large-scale, high-density storage devices must make allowances for the temperature variations caused by the heat of reaction between hydrogen and MH alloys, which may impact the storage characteristics. In this study, we propose a numerical model for the design and evaluation of hydrogen storage devices using MH alloys. Hydrogen desorption reaction behavior for an alloy is observed in terms of temperature and reaction rate. This behavioral correlation is used as the basis for a comprehensive simulation model of the alloy system. Calculated results are found to be in good agreement with experimentally measured data, indicating that the model may be applied to multiple system geometries, scales, and alloy compositions.

  7. Volumetric hydrogen storage in single-walled carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Liu, C.; Yang, Q. H.; Tong, Y.; Cong, H. T.; Cheng, H. M.

    2002-04-01

    Macroscopically long ropes of aligned single-walled carbon nanotubes (SWNTs), synthesized by a hydrogen and argon arc discharge method, were cold pressed into tablets without any binder for measurements of their volumetric hydrogen storage capacity. The typical apparent density of the tablets was measured to be around 1.7 g/cm3 with respect to a molding pressure of 0.75 Gpa. A volumetric and mass hydrogen storage capacity of 68 kg H2/m3 and 4.0 wt %, respectively, was achieved at room temperature under a pressure of 11 MPa for suitably pretreated SWNT tablets, and more than 70% of the hydrogen adsorbed can be released under ambient pressure at room temperature. Pore structure analysis indicated that the molding process diminished the mesopore volume of the SWNT ropes, but exerts little influence on their intrinsic pore textures.

  8. HYDROGEN CONCENTRATIONS DURING STORAGE OF 3013 OXIDE SAMPLES

    SciTech Connect

    Hensel, S.; Askew, N.; Laurinat, J.

    2011-03-14

    As part of a surveillance program intended to ensure the safe storage of plutonium bearing nuclear materials in the Savannah River Site (SRS) K-Area Materials Storage (KAMS), samples of these materials are shipped to Savannah River National Laboratory (SRNL) for analysis. These samples are in the form of solids or powders which will have absorbed moisture. Potentially flammable hydrogen gas is generated due to radiolysis of the moisture. The samples are shipped for processing after chemical analysis. To preclude the possibility of a hydrogen deflagration or detonation inside the shipping containers, the shipping times are limited to ensure that hydrogen concentration in the vapor space of every layer of confinement is below the lower flammability limit of 4 volume percent (vol%). This study presents an analysis of the rate of hydrogen accumulation due to radiolysis and calculation of allowable shipping times for typical KAMS materials.

  9. Hydrogen Storage in Titanium-decorated Boron Buckyball

    NASA Astrophysics Data System (ADS)

    Li, Jia; Zhou, Gang; Duan, Wenhui; Lee, Hoonkyung; Ihm, Jisoon

    2008-03-01

    Using first-principles electronic structure calculations, we investigate the potential of Ti-decorated B80 for hydrogen storage medium. The Ti-decorated B80 has the merit of an unexpected large binding energy of a Ti atom to B80 which can overcome the problem of metal clustering. Up to four hydrogen molecules are found to be adsorbed on a single Ti atom coated on B80. At high Ti coverage, we show that the Ti-decorated B80 can adsorb up to 5 wt% hydrogen and the calculated binding energy falls in the desirable range of 0.2-0.6eV/H2 which is suitable for reversible hydrogen storage at room-temperature, near-ambient-pressure conditions.

  10. Calcium-decorated carbyne networks as hydrogen storage media.

    PubMed

    Sorokin, Pavel B; Lee, Hoonkyung; Antipina, Lyubov Yu; Singh, Abhishek K; Yakobson, Boris I

    2011-07-13

    Among the carbon allotropes, carbyne chains appear outstandingly accessible for sorption and very light. Hydrogen adsorption on calcium-decorated carbyne chain was studied using ab initio density functional calculations. The estimation of surface area of carbyne gives the value four times larger than that of graphene, which makes carbyne attractive as a storage scaffold medium. Furthermore, calculations show that a Ca-decorated carbyne can adsorb up to 6 H(2) molecules per Ca atom with a binding energy of ∼0.2 eV, desirable for reversible storage, and the hydrogen storage capacity can exceed ∼8 wt %. Unlike recently reported transition metal-decorated carbon nanostructures, which suffer from the metal clustering diminishing the storage capacity, the clustering of Ca atoms on carbyne is energetically unfavorable. Thermodynamics of adsorption of H(2) molecules on the Ca atom was also investigated using equilibrium grand partition function.

  11. Nanosizing and nanoconfinement: new strategies towards meeting hydrogen storage goals.

    PubMed

    de Jongh, Petra E; Adelhelm, Philipp

    2010-12-17

    Hydrogen is expected to play an important role as an energy carrier in a future, more sustainable society. However, its compact, efficient, and safe storage is an unresolved issue. One of the main options is solid-state storage in hydrides. Unfortunately, no binary metal hydride satisfies all requirements regarding storage density and hydrogen release and uptake. Increasingly complex hydride systems are investigated, but high thermodynamic stabilities as well as slow kinetics and poor reversibility are important barriers for practical application. Nanostructuring by ball-milling is an established method to reduce crystallite sizes and increase reaction rates. Since five years attention has also turned to alternative preparation techniques that enable particle sizes below 10 nanometers and are often used in conjunction with porous supports or scaffolds. In this Review we discuss the large impact of nanosizing and -confinement on the hydrogen sorption properties of metal hydrides. We illustrate possible preparation strategies, provide insight into the reasons for changes in kinetics, reversibility and thermodynamics, and highlight important progress in this field. All in all we provide the reader with a clear view of how nanosizing and -confinement can beneficially affect the hydrogen sorption properties of the most prominent materials that are currently considered for solid-state hydrogen storage.

  12. Modular Energy Storage System for Hydrogen Fuel Cell Vehicles

    SciTech Connect

    Thomas, Janice

    2010-08-27

    The objective of the project is to develop technologies, specifically power electronics, energy storage electronics and controls that provide efficient and effective energy management between electrically powered devices in alternative energy vehicles plug-in electric vehicles, hybrid vehicles, range extended vehicles, and hydrogen-based fuel cell vehicles. The in-depth research into the complex interactions between the lower and higher voltage systems from data obtained via modeling, bench testing and instrumented vehicle data will allow an optimum system to be developed from a performance, cost, weight and size perspective. The subsystems are designed for modularity so that they may be used with different propulsion and energy delivery systems. This approach will allow expansion into new alternative energy vehicle markets.

  13. Iron-titanium-mischmetal alloys for hydrogen storage

    DOEpatents

    Sandrock, Gary Dale

    1978-01-01

    A method for the preparation of an iron-titanium-mischmetal alloy which is used for the storage of hydrogen. The alloy is prepared by air-melting an iron charge in a clay-graphite crucible, adding titanium and deoxidizing with mischmetal. The resultant alloy contains less than about 0.1% oxygen and exhibits a capability for hydrogen sorption in less than half the time required by vacuum-melted, iron-titanium alloys.

  14. Hydrogen storage in Earth's mantle and core

    NASA Technical Reports Server (NTRS)

    Prewitt, Charles T.

    1994-01-01

    Two different approaches to explaining how hydrogen might be stored in the mantle are illustrated by a number of papers published over the past 25-30 years, but there has been little attempt to provide objective comparisons of the two. One approach invokes the presence in the mantle of dense hydrous magnesium silicates (DHMS) stable at elevated pressures and temperatures. The other involves nominally anhydrous minerals (NAM) that contain hydrogen as a minor constituent on the ppm level. Experimental studies on DHMS indicate these phases may be stable to pressures and temperatures as high at 16 GPa and 1200 C. This temperature is lower than that indicated by a mantle geotherm at 16 GPa, but may be reasonable for a subducting slab. It is possible that other DHMS could be stable to even higher pressures, but little is known about maximum temperature limits. For NAM, small amounts of hydrogen (up to several hundred ppm) have been detected in olivine, orthopyroxene, clinopyroxene, and garnet recovered from xenoliths in kimberlites, eclogites, and alkali basalts; it has been demonstrated that synthetic wadsleyite and perovskite can accommodate significant amounts of hydrogen. A number of problems are associated with each possibility. For NAM originating in the mantle, one would like to assume that the hydrogen measured in samples recovered on Earth's surface was incorporated when the phase-crystallized at high temperatures and pressures, but it could have been introduced during transport to the surface. Major problems for the DHMS proponents are that none of these phases have been found as minerals and little is yet known about their stabilities in systems containing other cations such as Fe, Al, and Ca.

  15. Development of Improved Composite Pressure Vessels for Hydrogen Storage

    SciTech Connect

    Newhouse, Norman L.

    2016-04-29

    Hexagon Lincoln started this DOE project as part of the Hydrogen Storage Engineering Center of Excellence (HSECoE) contract on 1 February 2009. The purpose of the HSECoE was the research and development of viable material based hydrogen storage systems for on-board vehicular applications to meet DOE performance and cost targets. A baseline design was established in Phase 1. Studies were then conducted to evaluate potential improvements, such as alternate fiber, resin, and boss materials. The most promising concepts were selected such that potential improvements, compared with the baseline Hexagon Lincoln tank, resulted in a projected weight reduction of 11 percent, volume increase of 4 percent, and cost reduction of 10 percent. The baseline design was updated in Phase 2 to reflect design improvements and changes in operating conditions specified by HSECoE Partners. Evaluation of potential improvements continued during Phase 2. Subscale prototype cylinders were designed and fabricated for HSECoE Partners’ use in demonstrating their components and systems. Risk mitigation studies were conducted in Phase 3 that focused on damage tolerance of the composite reinforcement. Updated subscale prototype cylinders were designed and manufactured to better address the HSECoE Partners’ requirements for system demonstration. Subscale Type 1, Type 3, and Type 4 tanks were designed, fabricated and tested. Laboratory tests were conducted to evaluate vacuum insulated systems for cooling the tanks during fill, and maintaining low temperatures during service. Full scale designs were prepared based on results from the studies of this program. The operating conditions that developed during the program addressed adsorbent systems operating at cold temperatures. A Type 4 tank would provide the lowest cost and lightest weight, particularly at higher pressures, as long as issues with liner compatibility and damage tolerance could be resolved. A Type 1 tank might be the choice if the

  16. Oxygen- and Lithium-Doped Hybrid Boron-Nitride/Carbon Networks for Hydrogen Storage.

    PubMed

    Shayeganfar, Farzaneh; Shahsavari, Rouzbeh

    2016-12-20

    Hydrogen storage capacities have been studied on newly designed three-dimensional pillared boron nitride (PBN) and pillared graphene boron nitride (PGBN). We propose these novel materials based on the covalent connection of BNNTs and graphene sheets, which enhance the surface and free volume for storage within the nanomaterial and increase the gravimetric and volumetric hydrogen uptake capacities. Density functional theory and molecular dynamics simulations show that these lithium- and oxygen-doped pillared structures have improved gravimetric and volumetric hydrogen capacities at room temperature, with values on the order of 9.1-11.6 wt % and 40-60 g/L. Our findings demonstrate that the gravimetric uptake of oxygen- and lithium-doped PBN and PGBN has significantly enhanced the hydrogen sorption and desorption. Calculations for O-doped PGBN yield gravimetric hydrogen uptake capacities greater than 11.6 wt % at room temperature. This increased value is attributed to the pillared morphology, which improves the mechanical properties and increases porosity, as well as the high binding energy between oxygen and GBN. Our results suggest that hybrid carbon/BNNT nanostructures are an excellent candidate for hydrogen storage, owing to the combination of the electron mobility of graphene and the polarized nature of BN at heterojunctions, which enhances the uptake capacity, providing ample opportunities to further tune this hybrid material for efficient hydrogen storage.

  17. Implementation for Model of Adsoptive Hydrogen Storage Using UDF in Fluent

    NASA Astrophysics Data System (ADS)

    Ye, Feng; Xiao, Jinsheng; Hu, Binxiang; Benard, Pierre; Chahine, Richard

    This paper builds an axisymmetrical geometry model and simulates the charging, domancy, discharging and domancy processes of hydrogen storage tank based on activated carbon bed in a steel container at room temperature (302K) and medium storage pressure (10 MPa). The CFD model is based on the mass, momentum and energy conservation equations of the hydrogen storage system formed of gaseous and adsorbed hydrogen, activated carbon bed and steel tank wall. The adsorption model is based on Dubinin-Astakov adsorption isotherms. The simulation is implemented using a finite volume method through the computational fluid dynamics commercial software Fluent. User defined functions (UDFs) hooked in Fluent software are given to set the boundary conditions or modify the mass and energy conservation equations.The simulating results have good agreement with experimental results. Results show that the temperature of central region is higher than that near the wall during the charging process,while the temperature of central region is lower than that near the wall during the discharging process.The amount of adsorbed hydrogen is greater than that of the compressed gaseous hydrogen. Hydrogen storage by adsorption on high surface area activated carbon has obvious advantages.

  18. Computational Discovery of Novel Hydrogen Storage Materials and Reactions

    NASA Astrophysics Data System (ADS)

    Wolverton, Christopher

    2009-03-01

    Practical hydrogen storage for mobile applications requires materials that exhibit high hydrogen densities, low decomposition temperatures, and fast kinetics for absorption and desorption. Unfortunately, no reversible materials are currently known that possess all of these attributes. Here we present an overview of our recent efforts aimed at developing a first-principles computational approach to the discovery of novel hydrogen storage materials. We have developed computational tools which enable accurate prediction of decomposition thermodynamics, crystal structures for unknown hydrides, and thermodynamically preferred decomposition pathways. We present examples that illustrate each of these three capabilities. Specifically, we focus on recent work on crystal structure and dehydriding reactions of borohydride materials, such as Mg(BH4)2, MgB12H12, and mixtures of complex hydrides such as the ternary LiBH4/LiNH2/MgH2 system.References:[0pt] (1) V. Ozolins, E. H. Majzoub, and C. Wolverton, ``First-Principles Prediction of a Ground State Crystal Structure of Magnesium Borohydride'', Phys. Rev. Lett. 100, 135501 (2008).(2) C. Wolverton, D. J. Siegel, A. R. Akbarzadeh, and V. Ozolins, ``Discovery of Novel Hydrogen Storage Materials: An Atomic Scale Computational Approach'', J. Phys. Condens. Matt. 20, 064228 (2008).(3) J. Yang, et al., ``A Self-Catalyzing Hydrogen Storage Material'' Angew. Chem. Int. Ed., 47, 882 (2008).(4) A. R. Akbarzadeh, V. Ozolins, and C. Wolverton, ``First-Principles Determination of Multicomponent Hydride Phase Diagrams: Application to the Li-Mg-N-H System'', Advanced Materials 19, 3233 (2007).(5) D. J. Siegel, C. Wolverton, and V. Ozolins, ``Thermodynamic Guidelines for the Prediction of Hydrogen Storage Reactions and their Application to Destabilized Hydride Mixtures'', Phys. Rev. B 76, 134102 (2007).

  19. Condensation and Storage of Hydrogen Cluster Ions

    DTIC Science & Technology

    1988-11-01

    Application to Hydrogen Mol- ecular Ion (H+) Ground State", J. Chem. Phys. 70(8), 3881-3 (1979). 58. Strand, Michael P .; Reinhardt, William P ...R radius of curvature L length of S.C. magnet (axial) Q cross section, throughput of pumping section r radius of annular plasma p integer A thickness...of plasma (annular) w plasma frequency p vo azimuthal velocity E° 0radial electric fieldr u mass to change ratio viii INTRODUCTION The future

  20. High capacity hydrogen storage materials: attributes for automotive applications and techniques for materials discovery.

    PubMed

    Yang, Jun; Sudik, Andrea; Wolverton, Christopher; Siegel, Donald J

    2010-02-01

    Widespread adoption of hydrogen as a vehicular fuel depends critically upon the ability to store hydrogen on-board at high volumetric and gravimetric densities, as well as on the ability to extract/insert it at sufficiently rapid rates. As current storage methods based on physical means--high-pressure gas or (cryogenic) liquefaction--are unlikely to satisfy targets for performance and cost, a global research effort focusing on the development of chemical means for storing hydrogen in condensed phases has recently emerged. At present, no known material exhibits a combination of properties that would enable high-volume automotive applications. Thus new materials with improved performance, or new approaches to the synthesis and/or processing of existing materials, are highly desirable. In this critical review we provide a practical introduction to the field of hydrogen storage materials research, with an emphasis on (i) the properties necessary for a viable storage material, (ii) the computational and experimental techniques commonly employed in determining these attributes, and (iii) the classes of materials being pursued as candidate storage compounds. Starting from the general requirements of a fuel cell vehicle, we summarize how these requirements translate into desired characteristics for the hydrogen storage material. Key amongst these are: (a) high gravimetric and volumetric hydrogen density, (b) thermodynamics that allow for reversible hydrogen uptake/release under near-ambient conditions, and (c) fast reaction kinetics. To further illustrate these attributes, the four major classes of candidate storage materials--conventional metal hydrides, chemical hydrides, complex hydrides, and sorbent systems--are introduced and their respective performance and prospects for improvement in each of these areas is discussed. Finally, we review the most valuable experimental and computational techniques for determining these attributes, highlighting how an approach that

  1. FUNDAMENTAL SAFETY TESTING AND ANALYSIS OF HYDROGEN STORAGE MATERIALS AND SYSTEMS

    SciTech Connect

    Anton, D

    2007-05-01

    Hydrogen is seen as the future automobile energy storage media due to its inherent cleanliness upon oxidation and its ready utilization in fuel cell applications. Its physical storage in light weight, low volume systems is a key technical requirement. In searching for ever higher gravimetric and volumetric density hydrogen storage materials and systems, it is inevitable that higher energy density materials will be studied and used. To make safe and commercially acceptable systems, it is important to understand quantitatively, the risks involved in using and handling these materials and to develop appropriate risk mitigation strategies to handle unforeseen accidental events. To evaluate these materials and systems, an IPHE sanctioned program was initiated in 2006 partnering laboratories from Europe, North America and Japan. The objective of this international program is to understanding the physical risks involved in synthesis, handling and utilization of solid state hydrogen storage materials and to develop methods to mitigate these risks. This understanding will support ultimate acceptance of commercially high density hydrogen storage system designs. An overview of the approaches to be taken to achieve this objective will be given. Initial experimental results will be presented on environmental exposure of NaAlH{sub 4}, a candidate high density hydrogen storage compound. The tests to be shown are based on United Nations recommendations for the transport of hazardous materials and include air and water exposure of the hydride at three hydrogen charge levels in various physical configurations. Additional tests developed by the American Society for Testing and Materials were used to quantify the dust cloud ignition characteristics of this material which may result from accidental high energy impacts and system breach. Results of these tests are shown along with necessary risk mitigation techniques used in the synthesis and fabrication of a prototype hydrogen storage

  2. Predicting New Materials for Hydrogen Storage Application

    PubMed Central

    Vajeeston, Ponniah; Ravindran, Ponniah; Fjellvåg, Helmer

    2009-01-01

    Knowledge about the ground-state crystal structure is a prerequisite for the rational understanding of solid-state properties of new materials. To act as an efficient energy carrier, hydrogen should be absorbed and desorbed in materials easily and in high quantities. Owing to the complexity in structural arrangements and difficulties involved in establishing hydrogen positions by x-ray diffraction methods, the structural information of hydrides are very limited compared to other classes of materials (like oxides, intermetallics, etc.). This can be overcome by conducting computational simulations combined with selected experimental study which can save environment, money, and man power. The predicting capability of first-principles density functional theory (DFT) is already well recognized and in many cases structural and thermodynamic properties of single/multi component system are predicted. This review will focus on possible new classes of materials those have high hydrogen content, demonstrate the ability of DFT to predict crystal structure, and search for potential meta-stable phases. Stabilization of such meta-stable phases is also discussed.

  3. Magnesium nanoparticles with transition metal decoration for hydrogen storage

    NASA Astrophysics Data System (ADS)

    Pasquini, Luca; Callini, Elsa; Brighi, Matteo; Boscherini, Federico; Montone, Amelia; Jensen, Torben R.; Maurizio, Chiara; Vittori Antisari, Marco; Bonetti, Ennio

    2011-11-01

    We report on the hydrogen storage behaviour of Mg nanoparticles (NPs) (size range 100 nm-1 μm) with metal-oxide core-shell morphology synthesized by inert gas condensation and decorated by transition metal (TM) (Pd or Ti) clusters via in situ vacuum deposition. The structure and morphology of the as-prepared and hydrogenated NPs is studied by electron microscopy, X-ray diffraction including in situ experiments and X-ray absorption spectroscopy, in order to investigate the relationships with the hydrogen storage kinetics measured by the volumetric Sieverts method. With both Pd and Ti, the decoration deeply improves the hydrogen sorption properties: previously inert NPs exhibit complete hydrogenation with fast transformation kinetics, good stability and reversible gravimetric capacity that can attain 6 wt%. In the case of Pd-decoration, the occurrence of Mg-Pd alloying is observed at high temperatures and in dependence of the hydrogen pressure conditions. These structural transformations modify both the kinetics and thermodynamics of hydride formation, while Ti-decoration has an effect only on the kinetics. The experimental results are discussed in relation with key issues such as the amount of decoration, the heat of mixing between TM and Mg and the binding energy between TM and hydrogen.

  4. Hydrogen Storage in Mesoporous Materials under High Pressure

    NASA Astrophysics Data System (ADS)

    Weinberger, Michelle; Somayazulu, Maddury; Hemley, Russell

    2008-03-01

    To date, the materials considered best candidates for hydrogen storage fuel cells include activated carbon and metal organic frameworks. Both very high surface area activated carbon and MOF-5 have been shown to adsorb around 4.5 wt % of hydrogen gas at 78 K. We have investigated the fundamental structural response of these materials to high pressure, as well as their behavior at high pressure when packed with dense hydrogen. Further investigation of these materials at low temperatures while still at elevated pressures may in fact provide a route for recovery of these hydrogen-packed materials to near ambient conditions. Covalent organic frameworks offer the potential for even better hydrogen storage capacity. These materials have significantly lower densities than the MOF materials and offer a significantly larger number of adsorption sites. Diamond anvil cells are uniquely suited for the study of these materials, allowing in situ measurements at high pressure as well as at low temperatures. Using X-ray diffraction and Raman spectroscopy and Infrared Spectroscopy we probe the behavior of the hydrogen confined in these porous materials at high pressure by tracking changes in the in situ high pressure x-ray diffraction patterns and shifts in the hydrogen vibron peaks.

  5. Hydrogen storage in magnesium clusters: quantum chemical study.

    PubMed

    Wagemans, Rudy W P; van Lenthe, Joop H; de Jongh, Petra E; van Dillen, A Jos; de Jong, Krijn P

    2005-11-30

    Magnesium hydride is cheap and contains 7.7 wt % hydrogen, making it one of the most attractive hydrogen storage materials. However, thermodynamics dictate that hydrogen desorption from bulk magnesium hydride only takes place at or above 300 degrees C, which is a major impediment for practical application. A few results in the literature, related to disordered materials and very thin layers, indicate that lower desorption temperatures are possible. We systematically investigated the effect of crystal grain size on the thermodynamic stability of magnesium and magnesium hydride, using ab initio Hartree-Fock and density functional theory calculations. Also, the stepwise desorption of hydrogen was followed in detail. As expected, both magnesium and magnesium hydride become less stable with decreasing cluster size, notably for clusters smaller than 20 magnesium atoms. However, magnesium hydride destabilizes more strongly than magnesium. As a result, the hydrogen desorption energy decreases significantly when the crystal grain size becomes smaller than approximately 1.3 nm. For instance, an MgH2 crystallite size of 0.9 nm corresponds to a desorption temperature of only 200 degrees C. This predicted decrease of the hydrogen desorption temperature is an important step toward the application of Mg as a hydrogen storage material.

  6. Hydrogen storage and ionic mobility in amide-halide systems.

    PubMed

    Anderson, Paul A; Chater, Philip A; Hewett, David R; Slater, Peter R

    2011-01-01

    We report the results of a systematic study of the effect of halides on hydrogen release and uptake in lithium amide and lithium imide, respectively. The reaction of lithium amide and lithium imide with lithium or magnesium chloride, bromide and iodide resulted in a series of amide-halide and imide-halide phases, only two of which have been reported previously. On heating with LiH or MgH2, the amide-halides synthesised all released hydrogen more rapidly than lithium amide itself, accompanied by much reduced, or in some cases undetectable, release of ammonia by-product. The imide-halides produced were found to hydrogenate more rapidly than lithium imide, reforming related amide-halide phases. The work was initiated to test the hypothesis that the incorporation of halide anions might improve the lithium ion conductivity of lithium amide and help maintain high lithium ion mobility at all stages of the de/rehydrogenation process, enhancing the bulk hydrogen storage properties of the system. Preliminary ionic conductivity measurements indicated that the most conducting amide- and imide-halide phases were also the quickest to release hydrogen on heating and to hydrogenate. We conclude that ionic conductivity may be an important parameter in optimising the materials properties of this and other hydrogen storage systems.

  7. Gas storage using fullerene based adsorbents

    NASA Technical Reports Server (NTRS)

    Loutfy, Raouf O. (Inventor); Lu, Xiao-Chun (Inventor); Li, Weijiong (Inventor); Mikhael, Michael G. (Inventor)

    2000-01-01

    This invention is directed to the synthesis of high bulk density high gas absorption capacity adsorbents for gas storage applications. Specifically, this invention is concerned with novel gas absorbents with high gravimetric and volumetric gas adsorption capacities which are made from fullerene-based materials. By pressing fullerene powder into pellet form using a conventional press, then polymerizing it by subjecting the fullerene to high temperature and high inert gas pressure, the resulting fullerene-based materials have high bulk densities and high gas adsorption capacities. By pre-chemical modification or post-polymerization activation processes, the gas adsorption capacities of the fullerene-based adsorbents can be further enhanced. These materials are suitable for low pressure gas storage applications, such as oxygen storage for home oxygen therapy uses or on-board vehicle natural gas storage. They are also suitable for storing gases and vapors such as hydrogen, nitrogen, carbon dioxide, and water vapor.

  8. Enhanced hydrogen storage in sandwich-structured rGO/Co1-xS/rGO hybrid papers through hydrogen spillover

    NASA Astrophysics Data System (ADS)

    Han, Lu; Qin, Wei; Jian, Jiahuang; Liu, Jiawei; Wu, Xiaohong; Gao, Peng; Hultman, Benjamin; Wu, Gang

    2017-08-01

    Reduced graphene oxide (rGO) based two-dimensional (2D) structures have been fabricated for electrochemical hydrogen storage. However, the effective transfer of atomic hydrogen to adjacent rGO surfaces is suppressed by binders, which are widely used in conventional electrochemical hydrogen storage electrodes, leading to a confining of the performance of rGO for hydrogen storage. As a proof of concept experiment, a novel strategy is developed to fabricate the binder-free sandwich-structured rGO/Co1-xS/rGO hybrid paper via facile ball milling and filtration process. Based on the structure investigation, Co1-xS is immobilized in the space between the individual rGO sheets by the creation of chemical ;bridges; (Csbnd S bonds). Through the Csbnd S bonds, the atomic hydrogen is transferred from Co1-xS to rGO accompanying a Csbnd H chemical bond formation. When used as an electrode, the hybrid paper exhibits an improved hydrogen storage capacity of 3.82 wt% and, most importantly, significant cycling stability for up to 50 cycles. Excluding the direct hydrogen storage contribution from the Co1-xS in the hybrid paper, the hydrogen storage ability of rGO is enhanced by 10× through the spillover effects caused by the Co1-xS modifier.

  9. Capacity recovery after storage negatively precharged nickel hydrogen cells

    NASA Technical Reports Server (NTRS)

    Lowery, John E.

    1993-01-01

    Tests were conducted to investigate the recovery of capacity lost during open circuit storage of negatively precharged nickel hydrogen batteries. Four Eagle Picher RNH-90-3 cells were used in the tests. Recovery procedures and test results are presented in outline and graphic form.

  10. High Surface Area Conducting Polymer Composites for Hydrogen Storage

    NASA Astrophysics Data System (ADS)

    Gutowska, Anna; Tarasevich, Barbara; Shin, Yongsoon; Ferris, Kim; Linehan, John; White, James

    2004-03-01

    We are investigating high surface area mesoporous conducting polymer composites as new materials for on-board hydrogen storage. A recent study reported significant levels of hydrogen storage in two conducting polymers, polyaniline (PANI) and polypyrrole (PPy) (8 wtPANI).1 We have used templated synthesis methods to obtain PPy and PANI composites with mesoporous structure. We have designed composites that offer a combination of several desirable properties: - favorable wt. - multiple mechanisms of hydrogen storage (physi-, chemi-sorption, and voids available for gas compression), and high surface area meoporous morphology for enhanced gas-material interactions and greater control of gas transport. Our experimental approaches to materials design were supported by computational methods aimed at developing predictive capabilities for the structure-property relationship (SPR) of electronic structure effects on hydrogen storage capacity in conducting polymers. Computational methods were also used to support design of mesoporous structures for optimized gas-material interactions and effective diffusion control of gas transport. 1. Cho, J. J.; Song, K. S.; Kim, J. W.; Kim, T. H.; Choo, K. Fuel Chemistry Div. Reprints 2002, 47, 790.

  11. Underwater Explosion Analysis of Hexogen-Enriched Novel Hydrogen Storage Alloy

    NASA Astrophysics Data System (ADS)

    Chen, Yuan; Chen, Xiang; Wu, Dejun; Xu, Sen; Liu, Dabin; Xu, Minxiao

    2016-01-01

    A novel hydrogen storage alloy was used in hexogen-based thermobaric explosive (RDX-based TBE). Two types of fashioned explosive charges with mass of 160 g and 500 g were used in this work. The energy of TBE was tested by underwater explosion. The results indicate hexogen-enriched novel hydrogen storage alloy can produce higher bubble energy than that enriched aluminum. The total useful energy was 4.7 % (160 g) and 6.4 % (500 g) higher than an explosive with the same aluminum content, and Trotyl (TNT) equivalent of 2.1 times. The heat of explosion test shows the similar result that the novel hydrogen storage alloy can improve the total energy, about 7.9 % higher than the aluminized.

  12. Simulation of Porous Medium Hydrogen Storage - Estimation of Storage Capacity and Deliverability for a North German anticlinal Structure

    NASA Astrophysics Data System (ADS)

    Wang, B.; Bauer, S.; Pfeiffer, W. T.

    2015-12-01

    Large scale energy storage will be required to mitigate offsets between electric energy demand and the fluctuating electric energy production from renewable sources like wind farms, if renewables dominate energy supply. Porous formations in the subsurface could provide the large storage capacities required if chemical energy carriers such as hydrogen gas produced during phases of energy surplus are stored. This work assesses the behavior of a porous media hydrogen storage operation through numerical scenario simulation of a synthetic, heterogeneous sandstone formation formed by an anticlinal structure. The structural model is parameterized using data available for the North German Basin as well as data given for formations with similar characteristics. Based on the geological setting at the storage site a total of 15 facies distributions is generated and the hydrological parameters are assigned accordingly. Hydraulic parameters are spatially distributed according to the facies present and include permeability, porosity relative permeability and capillary pressure. The storage is designed to supply energy in times of deficiency on the order of seven days, which represents the typical time span of weather conditions with no wind. It is found that using five injection/extraction wells 21.3 mio sm³ of hydrogen gas can be stored and retrieved to supply 62,688 MWh of energy within 7 days. This requires a ratio of working to cushion gas of 0.59. The retrievable energy within this time represents the demand of about 450000 people. Furthermore it is found that for longer storage times, larger gas volumes have to be used, for higher delivery rates additionally the number of wells has to be increased. The formation investigated here thus seems to offer sufficient capacity and deliverability to be used for a large scale hydrogen gas storage operation.

  13. Integrated Refrigeration and Storage for Advanced Liquid Hydrogen Operations

    NASA Technical Reports Server (NTRS)

    Swanger, A. M.; Notardonato, W. U.; Johnson, W. L.; Tomsik, T. M.

    2016-01-01

    NASA has used liquefied hydrogen (LH2) on a large scale since the beginning of the space program as fuel for the Centaur and Apollo upper stages, and more recently to feed the three space shuttle main engines. The LH2 systems currently in place at the Kennedy Space Center (KSC) launch pads are aging and inefficient compared to the state-of-the-art. Therefore, the need exists to explore advanced technologies and operations that can drive commodity costs down, and provide increased capabilities. The Ground Operations Demonstration Unit for Liquid Hydrogen (GODU-LH2) was developed at KSC to pursue these goals by demonstrating active thermal control of the propellant state by direct removal of heat using a cryocooler. The project has multiple objectives including zero loss storage and transfer, liquefaction of gaseous hydrogen, and densification of liquid hydrogen. The key technology challenge was efficiently integrating the cryogenic refrigerator into the LH2 storage tank. A Linde LR1620 Brayton cycle refrigerator is used to produce up to 900W cooling at 20K, circulating approximately 22 g/s gaseous helium through the hydrogen via approximately 300 m of heat exchanger tubing. The GODU-LH2 system is fully operational, and is currently under test. This paper will discuss the design features of the refrigerator and storage system, as well as the current test results.

  14. Thermal management technology for hydrogen storage: Fullerene option

    SciTech Connect

    Wang, J.C.; Chen, F.C.; Murphy, R.W.

    1996-05-28

    Fullerenes were picked as first option for H storage because of potentially high volumetric and gravimetric densities. Results indicate that about 6 wt% H (corresponding to C{sub 60}H{sub 48}) can be added to and taken out of fullerenes. A model with thermally activated hydrogenation/dehydrogenation was developed. Activation energies were estimated to be 100 and 160 kJ/mole (1.0 and 1.6 eV/H{sub 2}) for hydrogenation and dehydrogenation, respectively; difference is interpreted as heat release during hydrogenation. The activation energies and hydrogenation heat may be modifiable by catalysts. Preliminary H storage simulations for a conceptually simple device were performed (a 1-m long hollow metal cylinder with inner dia 0.02 m filled with fullerene powders). Results indicate that the thermal diffusivity of the fullerenes controls the hydrogenation and dehydrogenation rates. Rates can be significantly modified by changing the thermal diffusivity, eg, by incorporating a metal mesh. The simulation suggest that thermal management is essential for efficient H storage devices using fullerenes. More controlled experiments, model development, and physical property determinations are needed; catalyst use also needs to be pursued. Future ORNL/MER cooperative work is planned.

  15. Parameter study of a vehicle-scale hydrogen storage system.

    SciTech Connect

    Johnson, Terry Alan; Kanouff, Michael P.

    2010-04-01

    Sandia National Laboratories has developed a vehicle-scale prototype hydrogen storage system as part of a Work For Others project funded by General Motors. This Demonstration System was developed using the complex metal hydride sodium alanate. For the current work, we have continued our evaluation of the GM Demonstration System to provide learning to DOE's hydrogen storage programs, specifically the new Hydrogen Storage Engineering Center of Excellence. Baseline refueling data during testing for GM was taken over a narrow range of optimized parameter values. Further testing was conducted over a broader range. Parameters considered included hydrogen pressure and coolant flow rate. This data confirmed the choice of design pressure of the Demonstration System, but indicated that the system was over-designed for cooling. Baseline hydrogen delivery data was insufficient to map out delivery rate as a function of temperature and capacity for the full-scale system. A more rigorous matrix of tests was performed to better define delivery capabilities. These studies were compared with 1-D and 2-D coupled multi-physics modeling results. The relative merits of these models are discussed along with opportunities for improved efficiency or reduced mass and volume.

  16. Nanostructured Magnesium Hydride for Reversible Hydrogen Storage

    NASA Astrophysics Data System (ADS)

    de Rango, P.; Chaise, A.; Fruchart, D.; Miraglia, S.; Marty, Ph.

    2013-05-01

    The aim of this work was to develop suitable materials to store hydrogen in a solid state. A systematic investigation of the co-milling process of magnesium hydride with a transition metal was undertaken in order to produce nanostructured and highly reactive powders. The initiating role of the transition metal was evidenced by in situ neutron diffraction experiments. High performances in terms of thermal and mechanical behavior were achieved introducing expanded graphite and compacting the mixture to form composite materials. Absorption and desorption kinetics have been measured versus temperature and H2 pressure.

  17. Hollow porous-wall glass microspheres for hydrogen storage

    DOEpatents

    Heung, Leung K.; Schumacher, Ray F.; Wicks, George G.

    2010-02-23

    A porous wall hollow glass microsphere is provided having a diameter range of between 1 to 200 microns, a density of between 1.0 to 2.0 gm/cc, a porous-wall structure having wall openings defining an average pore size of between 10 to 1000 angstroms, and which contains therein a hydrogen storage material. The porous-wall structure facilitates the introduction of a hydrogen storage material into the interior of the porous wall hollow glass microsphere. In this manner, the resulting hollow glass microsphere can provide a membrane for the selective transport of hydrogen through the porous walls of the microsphere, the small pore size preventing gaseous or liquid contaminants from entering the interior of the hollow glass microsphere.

  18. Sodium alanate nanoparticles--linking size to hydrogen storage properties.

    PubMed

    Baldé, Cornelis P; Hereijgers, Bart P C; Bitter, Johannes H; de Jong, Krijn P

    2008-05-28

    Important limitations in the application of light metal hydrides for hydrogen storage are slow kinetics and poor reversibility. To alleviate these problems doping and ball-milling are commonly applied, for NaAlH 4 leading to particle sizes down to 150 nm. By wet-chemical synthesis we have prepared carbon nanofiber-supported NaAlH 4 with discrete particle size ranges of 1-10 microm, 19-30 nm, and 2-10 nm. The hydrogen desorption temperatures and activation energies decreased from 186 degrees C and 116 kJ.mol (-1) for the largest particles to 70 degrees C and 58 kJ.mol (-1) for the smallest particles. In addition, decreasing particle sizes lowered the pressures needed for reloading. This reported size-performance correlation for NaAlH 4 may guide hydrogen storage research for a wide range of nanostructured light (metal) hydrides.

  19. Evaluating topologically diverse metal–organic frameworks for cryo-adsorbed hydrogen storage

    SciTech Connect

    Gómez-Gualdrón, Diego A.; Colón, Yamil J.; Zhang, Xu; Wang, Timothy C.; Chen, Yu-Sheng; Hupp, Joseph T.; Yildirim, Taner; Farha, Omar K.; Zhang, Jian; Snurr, Randall Q.

    2016-01-01

    Metal–organic frameworks (MOFs) are porous materials synthesized by combining inorganic and organic molecular building blocks into crystalline networks of distinct topologies. Due to the combinatorial possibilities, there are millions of possible MOF structures. Aiming to exploit their exceptional tunability, surface areas and pore volumes, researchers have investigated MOFs for storage of gaseous fuels such as hydrogen for over a decade, but a suitable MOF to store hydrogen at ambient conditions has not yet been found. Here, we sought to rapidly determine the viability of using MOFs for hydrogen storage at recently proposed, cryogenic operating conditions. We constructed a large and structurally diverse set of 13 512 potential MOF structures based on 41 different topologies and used molecular simulation to determine MOF hydrogen deliverable capacities between 100 bar/77 K and 5 bar/160 K. The highest volumetric deliverable capacity was 57 g L-1 of MOF, which surpasses the 37 g L-1 of tank of the incumbent technology (compressing hydrogen to 700 bar at ambient temperature). To validate our in silico MOF construction method, we synthesized a new isoreticular family of MOFs (she-MOF-x series) based on the she topology, which is extremely rare among MOFs. To validate our hydrogen storage predictions, we activated and measured hydrogen adsorption on she-MOF-1 and NU-1103. The latter MOF showed outstanding stability and a good combination of volumetric and gravimetric performance, presenting 43.2 g L-1 of MOF and 12.6 wt% volumetric and gravimetric deliverable capacities, respectively.

  20. SiC nanotubes: A novel material for hydrogen storage.

    PubMed

    Mpourmpakis, Giannis; Froudakis, George E; Lithoxoos, George P; Samios, Jannis

    2006-08-01

    A multiscale theoretical approach is used for the investigation of hydrogen storage in silicon-carbon nanotubes (SiCNTs). First, ab initio calculations at the density functional level of theory (DFT) showed an increase of 20% in the binding energy of H2 in SiCNTs compared with pure carbon nanotubes (CNTs). This is explained by the alternative charges that exist in the SiCNT walls. Second, classical Monte Carlo simulation of nanotube bundles showed an even larger increase of the storage capacity in SiCNTs, especially in low temperature and high-pressure conditions. Our results verify in both theoretical levels that SiCNTs seem to be more suitable materials for hydrogen storage than pure CNTs.

  1. Development and validation of a slurry model for chemical hydrogen storage in fuel cell vehicle applications

    NASA Astrophysics Data System (ADS)

    Brooks, Kriston P.; Pires, Richard P.; Simmons, Kevin L.

    2014-12-01

    The U.S. Department of Energy's (DOE) Hydrogen Storage Engineering Center of Excellence (HSECoE) is developing models for hydrogen storage systems for fuel cell-based light duty vehicle applications for a variety of promising materials. These transient models simulate the performance of the storage system for comparison to the DOE's Technical Targets and a set of four drive cycles. PNNL developed models to simulate the performance and suitability of slurry-based chemical hydrogen storage materials. The storage systems of both a representative exothermic system based on ammonia borane and an endothermic system based on alane were developed and modeled in Simulink®. Once complete, the reactor and radiator components of the model were validated with experimental data. The system design parameters were adjusted to allow the model to successfully meet a highway cycle, an aggressive cycle, a cold-start cycle, and a hot drive cycle. Finally, a sensitivity analysis was performed to identify the range of material properties where these DOE targets and drive cycles could be met. Materials with a heat of reaction >11 kJ mol-1 H2 generated and a slurry hydrogen capacity of >11.4% will meet the on-board efficiency and gravimetric capacity targets, respectively.

  2. Development and Validation of a Slurry Model for Chemical Hydrogen Storage in Fuel Cell Applications

    SciTech Connect

    Brooks, Kriston P.; Pires, Richard P.; Simmons, Kevin L.

    2014-07-25

    The US Department of Energy's (DOE) Hydrogen Storage Engineering Center of Excellence (HSECoE) is developing models for hydrogen storage systems for fuel cell-based light duty vehicle applications for a variety of promising materials. These transient models simulate the performance of the storage system for comparison to the DOE’s Technical Targets and a set of four drive cycles. The purpose of this research is to describe the models developed for slurry-based chemical hydrogen storage materials. The storage systems of both a representative exothermic system based on ammonia borane and endothermic system based on alane were developed and modeled in Simulink®. Once complete the reactor and radiator components of the model were validated with experimental data. The model was then run using a highway cycle, an aggressive cycle, cold-start cycle and hot drive cycle. The system design was adjusted to meet these drive cycles. A sensitivity analysis was then performed to identify the range of material properties where these DOE targets and drive cycles could be met. Materials with a heat of reaction greater than 11 kJ/mol H2 generated and a slurry hydrogen capacity of greater than 11.4% will meet the on-board efficiency and gravimetric capacity targets, respectively.

  3. Hydrogen Storage Studies of Palladium-Cobalt alloy nanoparticles dispersed Nitrogen Doped Graphene

    NASA Astrophysics Data System (ADS)

    Pullamsetty, Ashok; Sundara, Ramaprabhu

    Solid state hydrogen storage has significant importance in the present scenario of depleting conventional energy sources. Recent studies reveal that nanomaterials can play a significant role in the performance enhancement of energy conversion and storage device. Carbon based nanomaterials are considered as suitable candidates for hydrogen storage due to their high porosity, large surface area and high chemical stability. The two dimensional graphene, which has been discovered recently, consists of a single layer of atoms arranged in a honeycomb lattice, exhibits surface area. In the present work, we have been studied the hydrogen storage properties of Palladium-Cobalt alloy nanoparticles dispersed nitrogen doped graphene (Pd3Co/NG). Graphitic oxide was prepared by Hummers method and mixed with Palladium Cobalt and melamine precursors. The compound was reduced in hydrogen atmosphere at 500 °C for 5 h. Structural and micro-structural characterization of these samples has been carried out by X-ray diffraction pattern (XRD), Raman spectroscopy, scanning electron microscope (SEM), transmission electron microscopy (TEM) and X-ray photo electro spectroscopy (XPS). The hydrogen adsorption measurements were carried out for NG as well as Pd3Co/NG at different temperatures (25-100 °C) and pressures (5-40 bar) using a high pressure Sieverts apparatus. The material Pd3Co/NG exhibits high storage capacity compared to NG due to spillover mechanism and the results have been discussed.

  4. Study on the dynamic behavior of Zn-based hydrogen generating cells as fuel storage for a PEM micro fuel cell system

    NASA Astrophysics Data System (ADS)

    Weiland, M.; Krumbholz, S.; Wagner, S.; Reichl, H.

    Portable fuel cell systems consist of three essential parts: the fuel cell stack, the fuel storage and the balance of plant (BOP) which contains all required peripheral components. Scaling down fuel cell systems to smaller dimensions in the power range of 1 mW to 1 W currently leads to an increased volume fraction of the peripheral components. Consequently it is necessary to forego peripheral components in small systems and develop passive systems. Furthermore fuel storage is a challenging issue for portable micro fuel cell systems. Common approaches for hydrogen storage, e.g. pressure cartridges or reversible metal hydrides yield a low energy density for the entire system. In our approach a gas evolving cell (GEC) is used to generate hydrogen "on demand". This allows to develop small micro fuel cell systems with a high energy density. The GEC is electrically connected in series to the fuel cell. Hydrogen is generated through the electro catalytic Zn-H 2O reaction and proportional to the cell current according to Faraday's law, which leads to a simple and passive system. The dynamic and long-term behavior of the GEC is studied experimentally in this work. The electrical and chemical behavior of the GEC plays an important role in the design and operation of the micro fuel cell system. Portable applications generally imply dynamic load profiles. Therefore the study focuses on the dynamic response of the GEC. The electric response of the GEC is examined for load pulses in the range of milliseconds with an amplitude of up to 150 mA for the lifecycle of a cell. The results are compared to the behavior of the GECs under an equivalent static load in order to draw conclusions on the effect of the dynamic load. Furthermore the electrical and chemical capacity of the GECs is examined for different loads. The obtained results provide an insight into the dynamic behavior of the GEC and provide the basis for the design and operation of the micro fuel cell system.

  5. Predicting hydrogen and methane adsorption in carbon nanopores for energy storage

    NASA Astrophysics Data System (ADS)

    Ihm, Yungok; Morris, James; Cooper, Valentino; Morris Lab, U. tennessee Collaboration; Advanced material Group, ORNL Collaboration

    2013-03-01

    There are increasing demands for alternate fuels for transportation, which requires safe, high energy density, lightweight storage materials. Experimental measurements and theoretical predictions show relatively low hydrogen storage capacities in various porous materials, limiting hydrogen as a viable alternative for automobiles. In this work, we use a continuum model based on van der Waals density functional (vdW-DF) calculations to elucidate the role that long-range interactions play in the hydrogen adsorption properties of model slit nanopores in carbon. The proper treatment of long-range interactions gives an optimal pore size for hydrogen storage of 8-9 Å (larger than previously predicted). Remarkably, we find a peak hydrogen density close to that of liquid H2 at ambient temperatures, in agreement with recent experimental results on pore-size dependent adsorption in nanoporous carbon. We then show that such nanopores would be better suited to storing methane, possibly providing an alternative to fill the gap between the capacity required by DOE goals and that attainable with current hydrogen storage technology. Research supported by the U.S. Department of Energy, Basic Energy Sciences, Materials Sciences and Engineering Division.

  6. Evaluation of Hydrogen Storage System Characteristics for Light-Duty Vehicle Applications (Poster)

    SciTech Connect

    Thornton, M.; Day, K.; Brooker, A.

    2010-05-01

    This poster presentation demonstrates an approach to evaluate trade-offs among hydrogen storage system characteristic across several vehicle configurations and estimates the sensitivity of hydrogen storage system improvements on vehicle viability.

  7. Life-Cycle Cost Analysis Highlights Hydrogen's Potential for Electrical Energy Storage (Fact Sheet)

    SciTech Connect

    Not Available

    2010-11-01

    This fact sheet describes NREL's accomplishments in analyzing life-cycle costs for hydrogen storage in comparison with other energy storage technologies. Work was performed by the Hydrogen Technologies and Systems Center.

  8. First-principles study of Ti-catalyzed hydrogen chemisorption on an Al surface: a critical first step for reversible hydrogen storage in NaAlH4.

    PubMed

    Chaudhuri, Santanu; Muckerman, James T

    2005-04-21

    Complex metal hydrides are perhaps the most promising hydrogen storage materials for a gradual transformation to a hydrogen-based economy. We have used a computational approach to aid the ongoing experimental effort to understand the reversible hydrogen storage in Ti-doped NaAlH(4) and propose a plausible first step in the rehydrogenation mechanism. The study provides insight into the catalytic role played by the Ti atoms on an Al surface in the chemisorption of molecular hydrogen and identifies the local arrangement of the Ti atoms responsible for the process. Our results can potentially lead to ways of making other similar metal hydrides reversible.

  9. Technical Assessment of Organic Liquid Carrier Hydrogen Storage Systems for Automotive Applications

    SciTech Connect

    Ahluwalia, R. K.; Hua, T. Q.; Peng, J. -K; Kromer, M.; Lasher, S.; McKenney, K.; Law, K.; Sinha, J.

    2011-06-21

    In 2007-2009, the DOE Hydrogen Program conducted a technical assessment of organic liquid carrier based hydrogen storage systems for automotive applications, consistent with the Program’s Multiyear Research, Development, and Demonstration Plan. This joint performance (ANL) and cost analysis (TIAX) report summarizes the results of this assessment. These results should be considered only in conjunction with the assumptions used in selecting, evaluating, and costing the systems discussed here and in the Appendices.

  10. Destabilisation of magnesium hydride by germanium as a new potential multicomponent hydrogen storage system.

    PubMed

    Walker, Gavin S; Abbas, Marwa; Grant, David M; Udeh, Chima

    2011-07-28

    MgH(2) has too high an operating temperature for many hydrogen storage applications. However, MgH(2) ball-milled with Ge leads to a thermodynamic destabilisation of >50 kJ mol(-1)(H(2)). This has dramatically reduced the temperature of dehydrogenation to 130 °C, opening up the potential for Mg-based multicomponent systems as hydrogen stores for a range of applications.

  11. Destabilized and catalyzed borohydride for reversible hydrogen storage

    DOEpatents

    Mohtadi, Rana F [Northville, MI; Nakamura, Kenji [Toyota, JP; Au, Ming [Martinez, GA; Zidan, Ragaiy [Alken, SC

    2012-01-31

    A process of forming a hydrogen storage material, including the steps of: providing a first material of the formula M(BH.sub.4).sub.X, where M is an alkali metal or an alkali earth metal, providing a second material selected from M(AlH.sub.4).sub.x, a mixture of M(AlH.sub.4).sub.x and MCl.sub.x, a mixture of MCl.sub.x and Al, a mixture of MCl.sub.x and AlH.sub.3, a mixture of MH.sub.x and Al, Al, and AlH.sub.3. The first and second materials are combined at an elevated temperature and at an elevated hydrogen pressure for a time period forming a third material having a lower hydrogen release temperature than the first material and a higher hydrogen gravimetric density than the second material.

  12. System level permeability modeling of porous hydrogen storage materials.

    SciTech Connect

    Kanouff, Michael P.; Dedrick, Daniel E.; Voskuilen, Tyler

    2010-01-01

    A permeability model for hydrogen transport in a porous material is successfully applied to both laboratory-scale and vehicle-scale sodium alanate hydrogen storage systems. The use of a Knudsen number dependent relationship for permeability of the material in conjunction with a constant area fraction channeling model is shown to accurately predict hydrogen flow through the reactors. Generally applicable model parameters were obtained by numerically fitting experimental measurements from reactors of different sizes and aspect ratios. The degree of channeling was experimentally determined from the measurements and found to be 2.08% of total cross-sectional area. Use of this constant area channeling model and the Knudsen dependent Young & Todd permeability model allows for accurate prediction of the hydrogen uptake performance of full-scale sodium alanate and similar metal hydride systems.

  13. Hydrogen storage in carbon nanotubes produced by CVD

    NASA Astrophysics Data System (ADS)

    Fonseca, A.; Pierard, N.; Tollis, S.; Bister, G.; Konya, Z.; Nagaraju, N.; Nagy, J. B.

    2002-06-01

    Single- and multi-wall carbon nanotubes synthesized by catalytic decomposition of methane and acetylene, respectively were studied for their hydrogen adsorption capacity in their hollow and on their outer surface. The hydrogen storage capacity of the samples was measured for pressures 0-9 bar at 295 K and at 77 K. The results at different temperatures on the crude sample (closed tubes 10-50 um long), on the purified sample (open tubes 10-50 μm long) and on the purified and broken sample (open tubes 0.1-0.7 pm long) show that breaking the nanotubes allows one to adsorb hydrogen in their hollow. In addition, the relative amounts of hydrogen adsorbed in the hollow and outer parts of the nanotubes can be distinguished.

  14. Natural diatomite modified as novel hydrogen storage material

    NASA Astrophysics Data System (ADS)

    Jin, Jiao; Zheng, Chenghui; Yang, Huaming

    2014-03-01

    Natural diatomite, subjected to different modifications, is investigated for hydrogen adsorption capacities at room temperature. An effective metal-modified strategy is developed to disperse platinum (Pt) and palladium (Pd) nanoparticles on the surface of diatomite. Hydrogen adsorption capacity of pristine diatomite (diatomite) is 0.463 wt.% at 2.63 MPa and 298 K, among the highest of the known sorbents, while that of acid-thermally activated diatomite (A-diatomite) could reach up to 0.833 wt.% due to the appropriate pore properties by activation. By incorporation with a small amount of Pt and Pd ( 0.5 wt.%), hydrogen adsorption capacities are enhanced to 0.696 wt.% and 0.980 wt.%, respectively, indicating that activated diatomite shows interesting application in the field of hydrogen storage at room temperature.

  15. Glass Bubbles Insulation for Liquid Hydrogen Storage Tanks

    NASA Technical Reports Server (NTRS)

    Sass, J. P.; SaintCyr, W. W.; Barrett, T. M.; Baumgartner, R. G.; Lott, J. W.; Fesmire, J. E.

    2009-01-01

    A full-scale field application of glass bubbles insulation has been demonstrated in a 218,000 L liquid hydrogen storage tank. This work is the evolution of extensive materials testing, laboratory scale testing, and system studies leading to the use of glass bubbles insulation as a cost efficient and high performance alternative in cryogenic storage tanks of any size. The tank utilized is part of a rocket propulsion test complex at the NASA Stennis Space Center and is a 1960's vintage spherical double wall tank with an evacuated annulus. The original perlite that was removed from the annulus was in pristine condition and showed no signs of deterioration or compaction. Test results show a significant reduction in liquid hydrogen boiloff when compared to recent baseline data prior to removal of the perlite insulation. The data also validates the previous laboratory scale testing (1000 L) and full-scale numerical modeling (3,200,000 L) of boiloff in spherical cryogenic storage tanks. The performance of the tank will continue to be monitored during operation of the tank over the coming years. KEYWORDS: Glass bubble, perlite, insulation, liquid hydrogen, storage tank.

  16. Structures and Electrochemical Hydrogen Storage Properties of the As-Spun RE-Mg-Ni-Co-Al-Based AB2-Type Alloys Applied to Ni-MH Battery

    NASA Astrophysics Data System (ADS)

    Zhang, Yanghuan; Yuan, Zeming; Shang, Hongwei; Li, Yaqin; Qi, Yan; Zhao, Dongliang

    2017-03-01

    In this paper, the La0.8-x Ce0.2Y x MgNi3.5Co0.4Al0.1 (x = 0, 0.05, 0.1, 0.15, 0.2) alloys were synthesized via smelting and melt spinning. The effect of Y content on the structure and electrochemical hydrogen storage characteristics of the as-cast and spun alloys was investigated. The identifications of XRD and SEM demonstrate that the experimental alloys possess a major phase LaMgNi4 and a minor phase LaNi5. The variation of Y content results in an obvious transformation of the phase abundance rather than phase composition in the alloys, namely LaMgNi4 phase increases while LaNi5 phase decreases with Y content growing. Furthermore, the replacement of Y for La causes the lattice constants and cell volume to clearly decrease and markedly refines the alloy grains. The electrochemical tests reveal that these alloys can obtain the maximum values of discharge capacity at the first cycling without any activation needed. With Y content growing, the discharge capacity of the alloys obviously declines, but its cycle stability remarkably improves. Moreover, the electrochemical dynamics of the alloys, involving the high-rate discharge ability, hydrogen diffusion coefficient (D), limiting current density (I L), and charge transfer rate, initially augment and then decrease with rising Y content.

  17. Structures and Electrochemical Hydrogen Storage Properties of the As-Spun RE-Mg-Ni-Co-Al-Based AB2-Type Alloys Applied to Ni-MH Battery

    NASA Astrophysics Data System (ADS)

    Zhang, Yanghuan; Yuan, Zeming; Shang, Hongwei; Li, Yaqin; Qi, Yan; Zhao, Dongliang

    2017-05-01

    In this paper, the La0.8- x Ce0.2Y x MgNi3.5Co0.4Al0.1 ( x = 0, 0.05, 0.1, 0.15, 0.2) alloys were synthesized via smelting and melt spinning. The effect of Y content on the structure and electrochemical hydrogen storage characteristics of the as-cast and spun alloys was investigated. The identifications of XRD and SEM demonstrate that the experimental alloys possess a major phase LaMgNi4 and a minor phase LaNi5. The variation of Y content results in an obvious transformation of the phase abundance rather than phase composition in the alloys, namely LaMgNi4 phase increases while LaNi5 phase decreases with Y content growing. Furthermore, the replacement of Y for La causes the lattice constants and cell volume to clearly decrease and markedly refines the alloy grains. The electrochemical tests reveal that these alloys can obtain the maximum values of discharge capacity at the first cycling without any activation needed. With Y content growing, the discharge capacity of the alloys obviously declines, but its cycle stability remarkably improves. Moreover, the electrochemical dynamics of the alloys, involving the high-rate discharge ability, hydrogen diffusion coefficient ( D), limiting current density ( I L), and charge transfer rate, initially augment and then decrease with rising Y content.

  18. High performance hydrogen storage from Be-BTB metal-organic framework at room temperature.

    PubMed

    Lim, Wei-Xian; Thornton, Aaron W; Hill, Anita J; Cox, Barry J; Hill, James M; Hill, Matthew R

    2013-07-09

    The metal-organic framework beryllium benzene tribenzoate (Be-BTB) has recently been reported to have one of the highest gravimetric hydrogen uptakes at room temperature. Storage at room temperature is one of the key requirements for the practical viability of hydrogen-powered vehicles. Be-BTB has an exceptional 298 K storage capacity of 2.3 wt % hydrogen. This result is surprising given that the low adsorption enthalpy of 5.5 kJ mol(-1). In this work, a combination of atomistic simulation and continuum modeling reveals that the beryllium rings contribute strongly to the hydrogen interaction with the framework. These simulations are extended with a thermodynamic energy optimization (TEO) model to compare the performance of Be-BTB to a compressed H2 tank and benchmark materials MOF-5 and MOF-177 in a MOF-based fuel cell. Our investigation shows that none of the MOF-filled tanks satisfy the United States Department of Energy (DOE) storage targets within the required operating temperatures and pressures. However, the Be-BTB tank delivers the most energy per volume and mass compared to the other material-based storage tanks. The pore size and the framework mass are shown to be contributing factors responsible for the superior room temperature hydrogen adsorption of Be-BTB.

  19. Hydrogen storage capacity characterization of carbon nanotubes by a microgravimetrical approach.

    PubMed

    Lan, Aidong; Mukasyan, Alexander

    2005-08-25

    An accurate gravimetric apparatus based on a contactless magnetic suspension microbalance was developed. This unit was used to measure the hydrogen storage capacity for a variety of carbon nanotubes (CNTs) at room temperature and hydrogen pressures up to 11.5 MPa. The results show that regardless of their synthesis methods, purities, and nanostructures all investigated CNT products possess relatively low hydrogen storage capacities (<0.2 wt %). For comparison, the adsorption characteristics of theses samples were also measured at a pressure of 0.1 MPa and liquid nitrogen temperature (approximately 77 K) by a conventional volumetric approach. The methodological aspects related to the accuracy of the hydrogen uptake measurements are also discussed.

  20. Thermodynamic Properties of Organometallic Dihydrogen Complexes for Hydrogen Storage Applications

    NASA Astrophysics Data System (ADS)

    Abrecht, David Gregory

    The mechanism and thermodynamic properties of hydrogen binding to the solid-state complexes [M(CO)dppe2][BArF24] (M = Mn, Re, Tc) and [M'Hdppe2][NTf2] (M' = Fe, Ru, Os) were investigated experimentally and computationally over the temperature range 298K-373K and pressure range 0-2800 torr, based on the Sieverts method. The bulk absorption behavior was found to be accurately described by Langmuir isotherms. Enthalpy and entropy values of ΔH° = -52.2 kJ/mol and ΔS° = -99.6 J/mol-K were obtained experimentally for hydrogen absorption onto [Mn(CO)dppe2][BArF24] from the Langmuir equilibrium constant, and values obtained from electronic structure calculations using the LANL2DZ-ECP basis set were found to successfully reproduce both the pressure-temperature-composition behavior and the thermodynamic values to within 5% of those obtained through experiment. Results from simulations for all complexes yielded large enthalpy values similar to metal hydride formation enthalpies for all complexes studied, and the substitution of the metal center reproduced qualitative binding strength trends of 5d>3d>4d consistent with those previously reported for the group 6 metals. X-ray diffraction patterns and Mössbauer spectra were taken to determine the thermal decomposition pathway for [FeH(η2-H 2)dppe2][NTf2]. Simulations at the B3LYP/TZVP level of theory and experimental Mössbauer spectra confirmed the direct thermal decomposition from singlet-state [FeH(η2-H 2)dppe2][NTf2] to triplet-state [FeHdppe 2][NTf2] under vacuum conditions at 398K. Evaluation of the partial quadrupole splitting values of Q(H2) = -0.245 mm/s from Mössbauer spectroscopy significantly differ from typical values obtained for hydrides, indicating an underutilized mechanism for identification of dihydrogen ligands. Singlet-state thermodynamic values from simulation were consistent with experimental observations for Ru and Os, and ruthenium complexes were found to have thermodynamic properties within

  1. Metal-organic frameworks: A new hydrogen storage system

    NASA Astrophysics Data System (ADS)

    Yaghi, Omar

    2004-03-01

    Metal-organic framework-5 (MOF-5) of composition Zn4O(BDC)3 (BDC = 1,4-benzenedi-carboxylate) with a cubic 3-D extended porous structure was found to be capable of adsorbing hydrogen up to 4.5 weight percent (17.2 hydrogen molecules per formula unit) at 78 K. At room temperature and pressures up to 20 bar this material has a hydrogen storage capacity which increases linearly as a function of the applied pressure up to 1.0 percent by weight at 20 bar. Inelastic Neutron Scattering spectroscopy of the rotational transitions of the adsorbed hydrogen molecules was performed on hydrogen loaded MOF-5 using doses equivalent to four, eight and twenty-four hydrogen molecules per formula unit at 10 K. The spectra show peaks at 10.3 and 12.3 meV that are sharper than those observed for hydrogen in other porous materials, indicating the presence of two well-defined binding sites (termed I and II), which we associate with hydrogen binding to zinc and the BDC linker, respectively. At the highest dose (twenty-four hydrogen molecules), the peak corresponding to site II splits into four peaks, suggesting that higher capacity for hydrogen may be achieved by the use of larger linkers. Indeed, preliminary studies on isoreticular (of the same topology) metal-organic framework-6 and 8 having cyclobutyl and benzene moieties respectively fused to the benzene of MOF-5 gave approximately double and quadruple (2.0 weight percent) the uptake found for MOF-5 at room temperature and 10 bar.

  2. Energy storage mechanism in aqueous fiber-shaped Li-ion capacitors based on aligned hydrogenated-Li4Ti5O12 nanowires.

    PubMed

    Zhao, Hao; Ma, Xiangwen; Bai, Jinglong; Yang, Zhenyu; Sun, Gengzhi; Zhang, Zhenxing; Pan, Xiaojun; Lan, Wei; Zhou, Jin Yuan; Xie, Erqing

    2017-06-22

    It is reported that Li ions can contribute a lot to the capacitance of aqueous Li-ion capacitors (LICs), which might be due to the intercalation/de-intercalation processes of Li(+) ions that also occur at the anodes. However the energy storage mechanism in the aqueous LIC system still requires further proof. In this work, a type of aqueous fiber-shaped LIC has been designed and developed using hydrogenated Li4Ti5O12 (H-LTO) anodes, active carbon (AC) cathodes, and LiCl/PVA gel electrolytes with a double-helical structure. The obtained single LTO wire electrode exhibits a high specific capacitance in volume (34.1 F cm(-3)) and superior cycling stabilities (∼100% over 100 000 cycles), both of which are due to the formed amorphous layers at the surface of the electrodes. Moreover, it is found via sweep voltammetry analysis that most of the energy stored in an aqueous fiber-shaped capacitor electrode is attributed to the Li ions' intercalation, whose content exceeds 85% at a low scan rate and gradually decreases with increasing scan rate; while the energy stored by the double electric layers remains almost unchanged with different scan rates. Furthermore, the well-matched wearable fiber-shaped LICs show high capacitive behaviors (18.44 μW h cm(-2)) and superior static/dynamic cycling stabilities. This research would provide some insight into the charge storage mechanism in electrodes in the aqueous system, and give more suggestions to develop high-energy-density fiber-shaped energy storage devices.

  3. Energetics of Hydrogen Storage Reactions: The Power of DFT

    NASA Astrophysics Data System (ADS)

    Herbst, Jan

    2005-03-01

    Calculations of hydrogen site energetics in LaNi5Hn (hexagonal P63mc crystal structure) and LaCo5Hn (orthorhombic Cmmm structure) have been performed within density functional theory (DFT). In each case DFT correctly identifies the most stable hydrogen site configuration, yields an accurate value for the enthalpy of hydride formation, and predicts hydrogen-richer hydrides. The novel hydrogen storage reaction LiNH2 + LiH <-> Li2NH + H2 has also been investigated, with the inclusion of zero point energies and finite temperature corrections. The generalized gradient approximation for the exchange-correlation energy functional μxc provides much better agreement with experiment than the local density approximation for the structural parameters as well as for the enthalpy of formation of LiNH2, LiH, and the reaction enthalpy. While the choice of μxc may have substantial impact on results, it is indisputably clear that DFT is a powerful tool for understanding hydrogen storage energetics.

  4. Theoretical study of hydrogen storage in a truncated tetrahedron hydrocarbon

    NASA Astrophysics Data System (ADS)

    Ishikawa, Shigeru; Yamabe, Tokio

    2017-02-01

    A hydrocarbon molecule, having a truncated tetrahedron shape with a suitable size for the storage of a hydrogen molecule, is designed using quantum chemical methods. The molecule consists of four benzene rings bridged by six vinylene groups at the 1, 3, and 5 carbon positions of each ring, and has a stoichiometry of C36H24. The molecular geometry optimized under T d symmetry by the B3LYP/cc-pVTZ method shows no imaginary frequencies. The size of the molecular cavity, measured by the distance between opposite vinylene groups, is 8.0 Å. The cavity has four openings along each tetrahedron face. The radius of the opening is approximately 2 Å. The system interacting with a hydrogen molecule is optimized by the MP2/cc-pVTZ method. The interaction energy is evaluated by an extrapolation method through increasing the basis set size of the hydrogen molecule from the cc-pVTZ to the cc-pV6Z with counterpoise corrections. The hydrogen molecule enters the opening by overcoming an energy barrier of +730 meV and locates at the center of the cavity with a binding energy of -140 meV. The high barrier arises from the small size of the opening. The binding energy is three times larger than that of a graphite surface and may allow hydrogen storage at milder temperatures and pressures than those required with graphite.

  5. Hydrogen storage in nanoporous carbon materials: myth and facts.

    PubMed

    Kowalczyk, Piotr; Hołyst, Robert; Terrones, Mauricio; Terrones, Humberto

    2007-04-21

    We used Grand canonical Monte Carlo simulation to model the hydrogen storage in the primitive, gyroid, diamond, and quasi-periodic icosahedral nanoporous carbon materials and in carbon nanotubes. We found that none of the investigated nanoporous carbon materials satisfy the US Department of Energy goal of volumetric density and mass storage for automotive application (6 wt% and 45 kg H(2) m(-3)) at considered storage condition. Our calculations indicate that quasi-periodic icosahedral nanoporous carbon material can reach the 6 wt% at 3.8 MPa and 77 K, but the volumetric density does not exceed 24 kg H(2) m(-3). The bundle of single-walled carbon nanotubes can store only up to 4.5 wt%, but with high volumetric density of 42 kg H(2) m(-3). All investigated nanoporous carbon materials are not effective against compression above 20 MPa at 77 K because the adsorbed density approaches the density of the bulk fluid. It follows from this work that geometry of carbon surfaces can enhance the storage capacity only to a limited extent. Only a combination of the most effective structure with appropriate additives (metals) can provide an efficient storage medium for hydrogen in the quest for a source of "clean" energy.

  6. Sc-phthalocyanine sheet: Promising material for hydrogen storage

    NASA Astrophysics Data System (ADS)

    Lü, Kun; Zhou, Jian; Zhou, Le; Wang, Qian; Sun, Qiang; Jena, Puru

    2011-10-01

    It has been a long-standing dream to have high surface area materials with isolated and exposed transition-metal ions for hydrogen storage. The flexible synthesis procedure proposed recently by M. Abel, et al. [J. Am. Chem. Soc. 133, 1203 (2011)] and A. Sperl et al. [J. Am. Chem. Soc. 133, 11007 (2011)] provides a different pathway to achieve this goal. Using first-principles theory and grand canonical Monte Carlo simulation, we carry out a systematic study of 3d transition metals (Sc to Zn)-phthalocyanine porous sheets and find that Sc-phthalocyanine can store 4.6 wt. % hydrogen at 298 K and 100 bar.

  7. Polymeric hydrogen diffusion barrier, high-pressure storage tank so equipped, method of fabricating a storage tank and method of preventing hydrogen diffusion

    DOEpatents

    Lessing, Paul A.

    2004-09-07

    An electrochemically active hydrogen diffusion barrier which comprises an anode layer, a cathode layer, and an intermediate electrolyte layer, which is conductive to protons and substantially impermeable to hydrogen. A catalytic metal present in or adjacent to the anode layer catalyzes an electrochemical reaction that converts any hydrogen that diffuses through the electrolyte layer to protons and electrons. The protons and electrons are transported to the cathode layer and reacted to form hydrogen. The hydrogen diffusion barrier is applied to a polymeric substrate used in a storage tank to store hydrogen under high pressure. A storage tank equipped with the electrochemically active hydrogen diffusion barrier, a method of fabricating the storage tank, and a method of preventing hydrogen from diffusing out of a storage tank are also disclosed.

  8. Polymeric hydrogen diffusion barrier, high-pressure storage tank so equipped, method of fabricating a storage tank and method of preventing hydrogen diffusion

    DOEpatents

    Lessing, Paul A [Idaho Falls, ID

    2008-07-22

    An electrochemically active hydrogen diffusion barrier which comprises an anode layer, a cathode layer, and an intermediate electrolyte layer, which is conductive to protons and substantially impermeable to hydrogen. A catalytic metal present in or adjacent to the anode layer catalyzes an electrochemical reaction that converts any hydrogen that diffuses through the electrolyte layer to protons and electrons. The protons and electrons are transported to the cathode layer and reacted to form hydrogen. The hydrogen diffusion barrier is applied to a polymeric substrate used in a storage tank to store hydrogen under high pressure. A storage tank equipped with the electrochemically active hydrogen diffusion barrier, a method of fabricating the storage tank, and a method of preventing hydrogen from diffusing out of a storage tank are also disclosed.

  9. Hydrogen Storage Needs for Early Motive Fuel Cell Markets

    SciTech Connect

    Kurtz, J.; Ainscough, C.; Simpson, L.; Caton, M.

    2012-11-01

    The National Renewable Energy Laboratory's (NREL) objective for this project is to identify performance needs for onboard energy storage of early motive fuel cell markets by working with end users, manufacturers, and experts. The performance needs analysis is combined with a hydrogen storage technology gap analysis to provide the U.S. Department of Energy (DOE) Fuel Cell Technologies Program with information about the needs and gaps that can be used to focus research and development activities that are capable of supporting market growth.

  10. Lifecycle Cost Analysis of Hydrogen Versus Other Technologies for Electrical Energy Storage

    SciTech Connect

    Steward, D.; Saur, G.; Penev, M.; Ramsden, T.

    2009-11-01

    This report presents the results of an analysis evaluating the economic viability of hydrogen for medium- to large-scale electrical energy storage applications compared with three other storage technologies: batteries, pumped hydro, and compressed air energy storage (CAES).

  11. A combined pressure-temperature synthesis approach towards novel hydrogen storage materials

    NASA Astrophysics Data System (ADS)

    Chellappa, Raja; Somayazulu, Maddury; Struzhkin, Viktor; Hemley, Russell

    2008-03-01

    There is a growing need to explore synthesis of novel hydrogen storage materials with very high hydrogen content (> 30 wt.%) as well as tuning materials in order to facilitate reversible hydrogen desorption and absorption. A combined pressure-temperature (P-T) approach holds considerable promise towards achieving these objectives. In this talk, we will present results from our on-going efforts to synthesize hydrogen clathrates with very high hydrogen content that can be recovered at moderate P-T conditions based on simple molecular systems including clathrates and van der Waals compounds, specifically H2O, CH4, NH3, and boron containing systems. The use of suitable additives to enhance stability will also be explored. Results will also be presented from the direct P-T synthesis of metastable light metal (Li, Mg, B- based) complex hydrides.

  12. A general model of electrochemical impedance spectroscopy and its application to hydrogen storage materials

    NASA Astrophysics Data System (ADS)

    Tokash, Justin Charles

    As the global need for energy increases, scientists and engineers have found a possible solution by using hydrogen to power our world. Although hydrogen can be combusted as a fuel, it is considered an energy carrier for use in fuel cells wherein it is consumed (oxidized) without the production of greenhouse gases. The U.S. Department of Energy (DOE) formed a Center of Excellence for Chemical Hydrogen Storage, and this work stems from that project. The DOE has identified boron hydrides as being the main compounds of interest as hydrogen storage materials. The various boron hydrides are then oxidized to release their hydrogen, thereby forming a "spent fuel" in the form of a lower boron hydride or even a boron oxide. The ultimate goal of this project is to take the oxidized boron hydrides as the spent fuel and hydrogenate them back to their original form so they can be used again as a fuel. Thus this research is essentially a boron hydride recycling project. One class of boron hydrides, called polyhedral boranes, became of interest to the DOE due to their ability to contain a sufficient amount of hydrogen and their physical and chemical safety attributes. Unfortunately, the research performed here has shown that polyhedral boranes do not react in such a way as to allow enough hydrogen to be released, nor do they appear to undergo hydrogenation from the spent fuel form back to the original hydride. After the polyhedral boranes were investigated, the project goals remained the same but the hydrogen storage material was switched by the DOE to ammonia borane. Ammonia borane was found to undergo an irreversible hydrogen release process, so a direct hydrogenation was not able to occur. To achieve the hydrogenation of the spent ammonia borane fuel, an indirect hydrogenation reaction is possible by using compounds called organotin hydrides. In this process, the organotin hydrides will hydrogenate the spent ammonia borane fuel at the cost of their own oxidation, which forms

  13. Quantifying and Addressing the DOE Material Reactivity Requirements with Analysis and Testing of Hydrogen Storage Materials & Systems

    SciTech Connect

    Khalil, Y. F.

    2012-04-30

    The objective of this project is to examine safety aspects of candidate hydrogen storage materials and systems being developed in the DOE Hydrogen Program. As a result of this effort, the general DOE safety target will be given useful meaning by establishing a link between the characteristics of new storage materials and the satisfaction of safety criteria. This will be accomplished through the development and application of formal risk analysis methods, standardized materials testing, chemical reactivity characterization, novel risk mitigation approaches and subscale system demonstration. The project also will collaborate with other DOE and international activities in materials based hydrogen storage safety to provide a larger, highly coordinated effort.

  14. Storage of hydrogen in powders with nanosized crystalline domains

    SciTech Connect

    Schwarz, R.B.

    1997-09-01

    The term nanostructured materials is being used in the literature to denote different materials prepared by different techniques: (a) by the gas condensation of vapors in a partial vacuum and (b) by mechanical alloying, a high energy ball milling technique. The authors discuss the origin of this confusion and propose a differentiating nomenclature. They then discuss the use of particles with nanosized structures for the storage of hydrogen.

  15. Cryogenic Propellant Storage and Transfer Engineering Development Unit Hydrogen Tank

    NASA Technical Reports Server (NTRS)

    Werkheiser, Arthur

    2015-01-01

    The Cryogenic Propellant Storage and Transfer (CPST) project has been a long-running program in the Space Technology Mission Directorate to enhance the knowledge and technology related to handling cryogenic propellants, specifically liquid hydrogen. This particular effort, the CPST engineering development unit (EDU), was a proof of manufacturability effort in support of a flight article. The EDU was built to find and overcome issues related to manufacturability and collect data to anchor the thermal models for use on the flight design.

  16. An improved storage bulb mount for DSN hydrogen masers

    NASA Technical Reports Server (NTRS)

    Dachel, P. R.; Russell, D. P.; Tucker, T. K.; Stratman, L. B.

    1979-01-01

    The presently used JPL hydrogen maser suspended atomic storage bulb and a rigid, single-plane mounted bulb are compared. The new bulb incorporates three major design changes: (1) mounting design; (2) alterations to the collimator; and (3) decrease in mass. These design changes are expected to increase the long-term stability of the frequency standard by reducing its sensitivity to vibration and thermal effects.

  17. Magnesium borohydride: from hydrogen storage to magnesium battery.

    PubMed

    Mohtadi, Rana; Matsui, Masaki; Arthur, Timothy S; Hwang, Son-Jong

    2012-09-24

    Beyond hydrogen storage: The first example of reversible magnesium deposition/stripping onto/from an inorganic salt was seen for a magnesium borohydride electrolyte. High coulombic efficiency of up to 94 % was achieved in dimethoxyethane solvent. This Mg(BH(4))(2) electrolyte was utilized in a rechargeable magnesium battery. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Hydrogen-Oxygen PEM Regenerative Fuel Cell Energy Storage System

    NASA Technical Reports Server (NTRS)

    Bents, David J.; Scullin, Vincent J.; Chang, Bei-Jiann; Johnson, Donald W.; Garcia, Christopher P.

    2005-01-01

    An introduction to the closed cycle hydrogen-oxygen polymer electrolyte membrane (PEM) regenerative fuel cell (RFC), recently constructed at NASA Glenn Research Center, is presented. Illustrated with explanatory graphics and figures, this report outlines the engineering motivations for the RFC as a solar energy storage device, the system requirements, layout and hardware detail of the RFC unit at NASA Glenn, the construction history, and test experience accumulated to date with this unit.

  19. Electric field enhanced hydrogen storage on polarizable materials substrates.

    PubMed

    Zhou, J; Wang, Q; Sun, Q; Jena, P; Chen, X S

    2010-02-16

    Using density functional theory, we show that an applied electric field can substantially improve the hydrogen storage properties of polarizable substrates. This new concept is demonstrated by adsorbing a layer of hydrogen molecules on a number of nanomaterials. When one layer of H(2) molecules is adsorbed on a BN sheet, the binding energy per H(2) molecule increases from 0.03 eV/H(2) in the field-free case to 0.14 eV/H(2) in the presence of an electric field of 0.045 a.u. The corresponding gravimetric density of 7.5 wt% is consistent with the 6 wt% system target set by Department of Energy for 2010. The strength of the electric field can be reduced if the substrate is more polarizable. For example, a hydrogen adsorption energy of 0.14 eV/H(2) can be achieved by applying an electric field of 0.03 a.u. on an AlN substrate, 0.006 a.u. on a silsesquioxane molecule, and 0.007 a.u. on a silsesquioxane sheet. Thus, application of an electric field to a polarizable substrate provides a novel way to store hydrogen; once the applied electric field is removed, the stored H(2) molecules can be easily released, thus making storage reversible with fast kinetics. In addition, we show that materials with rich low-coordinated nonmetal anions are highly polarizable and can serve as a guide in the design of new hydrogen storage materials.

  20. Electric field enhanced hydrogen storage on polarizable materials substrates

    PubMed Central

    Zhou, J.; Wang, Q.; Sun, Q.; Jena, P.; Chen, X. S.

    2010-01-01

    Using density functional theory, we show that an applied electric field can substantially improve the hydrogen storage properties of polarizable substrates. This new concept is demonstrated by adsorbing a layer of hydrogen molecules on a number of nanomaterials. When one layer of H2 molecules is adsorbed on a BN sheet, the binding energy per H2 molecule increases from 0.03 eV/H2 in the field-free case to 0.14 eV/H2 in the presence of an electric field of 0.045 a.u. The corresponding gravimetric density of 7.5 wt% is consistent with the 6 wt% system target set by Department of Energy for 2010. The strength of the electric field can be reduced if the substrate is more polarizable. For example, a hydrogen adsorption energy of 0.14 eV/H2 can be achieved by applying an electric field of 0.03 a.u. on an AlN substrate, 0.006 a.u. on a silsesquioxane molecule, and 0.007 a.u. on a silsesquioxane sheet. Thus, application of an electric field to a polarizable substrate provides a novel way to store hydrogen; once the applied electric field is removed, the stored H2 molecules can be easily released, thus making storage reversible with fast kinetics. In addition, we show that materials with rich low-coordinated nonmetal anions are highly polarizable and can serve as a guide in the design of new hydrogen storage materials. PMID:20133647

  1. Hydrogen Storage Properties of Rigid Three-Dimensional Hofmann Clathrate Derivatives: The Effects of Pore Size

    SciTech Connect

    Culp, J.T.; Natesakhawat, Sittichai; Smith, M.R.; Bittner, E.; Matranga, C.S.; Bockrath, B.

    2008-05-01

    The effects of pore size on the hydrogen storage properties of a series of pillared layered solids based on the M(L)[M'(CN)4] structural motif, where M ) Co or Ni, L ) pyrazine (pyz), 4,4'-bipyridine (bpy), or 4,4'-dipyridylacetylene (dpac), and M' ) Ni, Pd, or Pt, has been investigated. The compounds all possess slitlike pores with constant in-plane dimensions and similar organic functionality. The pore heights vary as a function of L and provide a means for a systematic investigation of the effects of pore dimension on hydrogen storage properties in porous materials. Hydrogen isotherms were measured at 77 and 87 K up to a pressure of 1 atm. The pyz pillared materials with the smallest pore dimensions store hydrogen at a pore density similar to that of liquid hydrogen. The adsorbed hydrogen density drops by a factor of 2 as the relative pore size is tripled in the dpac material. The decreased storage efficiency diminishes the expected gravimetric gain in capacity for the larger pore materials. The heats of adsorption were found to range from 6 to 8 kJ/mol in the series and weakly correlate with pore size.

  2. Hydrogen Storage Properties of Rigid Three-Dimensional Hofmann Clathrate Derivatives: The Effects of Pore Size

    SciTech Connect

    Culp, Jeffery T.; Natesakhawat, Sittichai; Smith, Milton R.; Bittner, Edward; Matranga, Christopher; Bockrath, Bradley

    2008-05-01

    The effects of pore size on the hydrogen storage properties of a series of pillared layered solids based on the M(L)[M'(CN)(4)] structural motif, where M = Co or Ni, L = pyrazine (pyz), 4,4'-bipyridine (bpy), or 4,4'-dipyridylacetylene (dpac), and M' = Ni, Pd, or Pt, has been investigated. The compounds all possess slitlike pores with constant in-plane dimensions and similar organic functionality. The pore heights vary as a function of L and provide a means for a systematic investigation of the effects of pore dimension on hydrogen storage properties in porous materials. Hydrogen isotherms were measured at 77 and 87 K up to a pressure of 1 atm. The pyz pillared materials with the smallest pore dimensions store hydrogen at a pore density similar to that of liquid hydrogen. The adsorbed hydrogen density drops by a factor of 2 as the relative pore size is tripled in the dpac material. The decreased storage efficiency diminishes the expected gravimetric gain in capacity for the larger pore materials. The heats of adsorption were found to range from 6 to 8 kJ/mol in the series and weakly correlate with pore size.

  3. Vehicular hydrogen storage using lightweight tanks (regenerative fuel cell systems)

    SciTech Connect

    Mitlitsky, F; Myers, B; Weisberg, A H

    1999-06-01

    Energy storage systems with extremely high specific energy (>400 Wh/kg) have been designed that use lightweight tankage to contain the gases generated by reversible (unitized) regenerative fuel cells (URFCs). Lawrence Livermore National Laboratory (LLNL) will leverage work for aerospace applications supported by other sponsors (including BMDO, NASA, and USAF) to develop URFC systems for transportation and utility applications. Lightweight tankage is important for primary fuel cell powered vehicles that use on-board storage of hydrogen. Lightweight pressure vessels with state-of-the-art performance factors were designed, and prototypes are being fabricated to meet the DOE 2000 goals (4000 Wh/kg, 12% hydrogen by weight, 700 Wh/liter, and $20/kWh in high volume production). These pressure vessels use technologies that are easily adopted by industrial partners. Advanced liners provide permeation barriers for gas storage and are mandrels for composite overwrap. URFCs are important to the efficient use of hydrogen as a transportation fuel and enabler of renewable energy. H{sub 2}/halogen URFCs may be advantageous for stationary applications whereas H{sub 2}/O{sub 2} or H{sub 2}/air URFCs are advantageous for vehicular applications. URFC research and development is required to improve performance (efficiency), reduce catalyst loading, understand engineering operation, and integrate systems. LLNL has the experimental equipment and advanced URFC membrane electrode assemblies (some with reduced catalyst loading) for evaluating commercial hardware (not funded by DOE in FY1999).

  4. Hydrogen storage and evolution catalysed by metal hydride complexes.

    PubMed

    Fukuzumi, Shunichi; Suenobu, Tomoyoshi

    2013-01-07

    The storage and evolution of hydrogen are catalysed by appropriate metal hydride complexes. Hydrogenation of carbon dioxide by hydrogen is catalysed by a [C,N] cyclometalated organoiridium complex, [Ir(III)(Cp*)(4-(1H-pyrazol-1-yl-κN(2))benzoic acid-κC(3))(OH(2))](2)SO(4) [Ir-OH(2)](2)SO(4), under atmospheric pressure of H(2) and CO(2) in weakly basic water (pH 7.5) at room temperature. The reverse reaction, i.e., hydrogen evolution from formate, is also catalysed by [Ir-OH(2)](+) in acidic water (pH 2.8) at room temperature. Thus, interconversion between hydrogen and formic acid in water at ambient temperature and pressure has been achieved by using [Ir-OH(2)](+) as an efficient catalyst in both directions depending on pH. The Ir complex [Ir-OH(2)](+) also catalyses regioselective hydrogenation of the oxidised form of β-nicotinamide adenine dinucleotide (NAD(+)) to produce the 1,4-reduced form (NADH) under atmospheric pressure of H(2) at room temperature in weakly basic water. In weakly acidic water, the complex [Ir-OH(2)](+) also catalyses the reverse reaction, i.e., hydrogen evolution from NADH to produce NAD(+) at room temperature. Thus, interconversion between NADH (and H(+)) and NAD(+) (and H(2)) has also been achieved by using [Ir-OH(2)](+) as an efficient catalyst and by changing pH. The iridium hydride complex formed by the reduction of [Ir-OH(2)](+) by H(2) and NADH is responsible for the hydrogen evolution. Photoirradiation (λ > 330 nm) of an aqueous solution of the Ir-hydride complex produced by the reduction of [Ir-OH(2)](+) with alcohols resulted in the quantitative conversion to a unique [C,C] cyclometalated Ir-hydride complex, which can catalyse hydrogen evolution from alcohols in a basic aqueous solution (pH 11.9). The catalytic mechanisms of the hydrogen storage and evolution are discussed by focusing on the reactivity of Ir-hydride complexes.

  5. Storage of Hydrogen in Single-Walled Carbon Nanotubes

    SciTech Connect

    Dillon, A. C.; Jones, K. M.; Bekkedahl, T. A.; Kiang, C. H.; Bethune, D. S.; Heben, M. J.

    1997-03-27

    Pores of molecular dimensions can adsorb large quantities of gases owing to the enhanced density of the adsorbed material inside the pores, a consequence of the attractive potential of the pore walls. Pederson and Broughton have suggested that carbon nanotubes, which have diameters of typically a few nanometres, should be able to draw up liquids by capillarity, and this effect has been seen for low-surface-tension liquids in large-diameter, multi-walled nanotubes. Here we show that a gas can condense to high density inside narrow, single-walled nanotubes (SWNTs). Temperature-programmed desorption spectroscopy shows that hydrogen will condense inside SWNTs under conditions that do not induce adsorption within a standard mesoporous activated carbon. The very high hydrogen uptake in these materials suggests that they might be effective as a hydrogen-storage material for fuel-cell electric vehicles.

  6. Enhancement of hydrogen storage capacity in hydrate lattices

    NASA Astrophysics Data System (ADS)

    Willow, Soohaeng Yoo; Xantheas, Sotiris S.

    2012-02-01

    First principles electronic structure calculations of the pentagonal dodecahedron (H2O)20 (D-cage) and tetrakaidecahedron (H2O)24 (T-cage), building blocks of structure I (sI) hydrate lattice, suggest that these can accommodate up to a maximum of 5 and 7 guest hydrogen molecules, respectively. For the pure hydrogen hydrate, Born-Oppenheimer molecular dynamics (BOMD) simulations of periodic (sI) hydrate lattices indicate that the guest molecules are released into the vapor phase via the hexagonal faces of the larger T-cages. The presence of methane in the larger T-cages was found to block this release, therefore suggesting possible scenarios for the stabilization of these coated clathrate hydrates and the potential enhancement of their hydrogen storage capacity.

  7. Reversible storage of hydrogen in destabilized LiBH4.

    PubMed

    Vajo, John J; Skeith, Sky L; Mertens, Florian

    2005-03-10

    Destabilization of LiBH4 for reversible hydrogen storage has been studied using MgH2 as a destabilizing additive. Mechanically milled mixtures of LiBH4 + (1/2)MgH2 or LiH + (1/2)MgB2 including 2-3 mol % TiCl3 are shown to reversibly store 8-10 wt % hydrogen. Variation of the equilibrium pressure obtained from isotherms measured at 315-400 degrees C indicate that addition of MgH2 lowers the hydrogenation/dehydrogenation enthalpy by 25 kJ/(mol of H2) compared with pure LiBH4. Formation of MgB2 upon dehydrogenation stabilizes the dehydrogenated state and, thereby, destabilizes the LiBH4. Extrapolation of the isotherm data yields a predicted equilibrium pressure of 1 bar at approximately 225 degrees C. However, the kinetics were too slow for direct measurements at these temperatures.

  8. Sodium hydrazinidoborane: a chemical hydrogen-storage material.

    PubMed

    Moury, Romain; Demirci, Umit B; Ichikawa, Takayuki; Filinchuk, Yaroslav; Chiriac, Rodica; van der Lee, Arie; Miele, Philippe

    2013-04-01

    Herein, we present the successful synthesis and full characterization (by (11) B magic-angle-spinning nuclear magnetic resonance spectroscopy, infrared spectroscopy, powder X-ray diffraction) of sodium hydrazinidoborane (NaN2 H3 BH3 , with a hydrogen content of 8.85 wt %), a new material for chemical hydrogen storage. Using lab-prepared pure hydrazine borane (N2 H4 BH3 ) and commercial sodium hydride as precursors, sodium hydrazinidoborane was synthesized by ball-milling at low temperature (-30 °C) under an argon atmosphere. Its thermal stability was assessed by thermogravimetric analysis and differential scanning calorimetry. It was found that under heating sodium hydrazinidoborane starts to liberate hydrogen below 60 °C. Within the range of 60-150 °C, the overall mass loss is as high as 7.6 wt %. Relative to the parent N2 H4 BH3 , sodium hydrazinidoborane shows improved dehydrogenation properties, further confirmed by dehydrogenation experiments under prolonged heating at constant temperatures of 80, 90, 95, 100, and 110 °C. Hence, sodium hydrazinidoborane appears to be more suitable for chemical hydrogen storage than N2 H4 BH3 . Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Electrochemical hydrogen storage of Ti-V-based body-centered-cubic phase alloy surface-modified with AB{sub 5} nanoparticles

    SciTech Connect

    Yu, X.B.; Walker, G.S.; Grant, D.M.; Wu, Z.; Xia, B.J.; Shen, J.

    2005-09-26

    A composite of Ti-V-based bcc phase alloy surface-modified with AB{sub 5} nanoparticles was prepared by ball milling. The composite showed significantly improved electrochemical hydrogen release capacities. For example, the 30 min ball milled Ti-30V-15Mn-15Cr+10 wt %AB{sub 5} showed a discharge capacity in the first cycle, at 353 K, of 886 mA h g{sup -1}, corresponding to 3.38 wt % of hydrogen, with a 45 mA g{sup -1} discharge current. It is thought that this high capacity is due to the enhanced electrochemical-catalytic activity from the alloy surface covered with AB{sub 5} nanoparticles, which not only have better charge-discharge capacity themselves, acting as both an electrocatalyst and a microcurrent collector, but also result in the greatly enhanced hydrogen atomic diffusivities in the nanocrystalline relative to their conventional coarse-grained counterparts. These results provide new insight for use of Ti-V-based bcc phase alloy for high-energy batteries.

  10. Electrochemical hydrogen storage of Ti-V-based body-centered-cubic phase alloy surface-modified with AB5 nanoparticles

    NASA Astrophysics Data System (ADS)

    Yu, X. B.; Walker, G. S.; Grant, D. M.; Wu, Z.; Xia, B. J.; Shen, J.

    2005-09-01

    A composite of Ti-V-based bcc phase alloy surface-modified with AB5 nanoparticles was prepared by ball milling. The composite showed significantly improved electrochemical hydrogen release capacities. For example, the 30 min ball milled Ti-30V-15Mn-15Cr +10wt%AB5 showed a discharge capacity in the first cycle, at 353 K, of 886mAhg-1, corresponding to 3.38 wt % of hydrogen, with a 45mAg-1 discharge current. It is thought that this high capacity is due to the enhanced electrochemical-catalytic activity from the alloy surface covered with AB5 nanoparticles, which not only have better charge-discharge capacity themselves, acting as both an electrocatalyst and a microcurrent collector, but also result in the greatly enhanced hydrogen atomic diffusivities in the nanocrystalline relative to their conventional coarse-grained counterparts. These results provide new insight for use of Ti-V-based bcc phase alloy for high-energy batteries.

  11. High-temperature electrochemical performance of low-cost La–Ni–Fe based hydrogen storage alloys with different preparation methods

    SciTech Connect

    Wang, Qiannan; Zhu, Ding; Zhou, Wanhai; Zhong, Chenglin; Wu, Chaoling; Chen, Yungui

    2016-04-15

    Highlights: • Effects of four different preparation processes were studied at 20/60 °C. • All NS + HT, RS and RS + HT processes can optimize the thermodynamic performance. • The HT process can provoke the precipitation of A{sub 2}B{sub 7} and leads to a poor cycling life. • Al exhibits the most remarkable dissolution for all the alloys, especially at 60 °C. - Abstract: In order to optimize the microstructure and high temperature electrochemical performances of low-cost AB{sub 5}-type Ml(NiMnAl){sub 4.2}Co{sub 0.3}Fe{sub 0.5} hydrogen storage electrode alloys, four different preparation methods including normal solidification (NS), normal solidification and 900 °C heat treatment (NS + HT), rapid solidification (RS), rapid solidification and 900 °C heat treatment (RS + HT) were adopted in this work. All alloys exhibit CaCu{sub 5} type hexagonal structure and there is a small amount of A{sub 2}B{sub 7} phase in NS + HT and RS + HT alloys. It is found the using of HT process can decrease the hydrogen equilibrium plateau pressure, the plateau slope and hysteresis at 40, 60 and 80 °C. The NS + HT and RS + HT alloys also possess better activation, high rate discharge performance, larger discharge capacity, but poor cycling performance due to the existence of A{sub 2}B{sub 7} phase which can accelerate dissolution of Ni, Mn and Fe elements in KOH alkaline electrolyte. The RS process can make alloy exhibit the best cycling performance especially at 60 °C.

  12. Synthesis, X-ray crystal structures, and gas sorption properties of pillared square grid nets based on paddle-wheel motifs: implications for hydrogen storage in porous materials.

    PubMed

    Chun, Hyungphil; Dybtsev, Danil N; Kim, Hyunuk; Kim, Kimoon

    2005-06-06

    A systematic modulation of organic ligands connecting dinuclear paddle-wheel motifs leads to a series of isomorphous metal-organic porous materials that have a three-dimensional connectivity and interconnected pores. Aromatic dicarboxylates such as 1,4-benzenedicarboxylate (1,4-bdc), tetramethylterephthalate (tmbdc), 1,4-naphthalenedicarboxylate (1,4-ndc), tetrafluoroterephthalate (tfbdc), or 2,6-naphthalenedicarboxylate (2,6-ndc) are linear linkers that form two-dimensional layers, and diamine ligands, 4-diazabicyclo[2.2.2]octane (dabco) or 4,4'-dipyridyl (bpy), coordinate at both sides of Zn(2) paddle-wheel units to bridge the layers vertically. The resulting open frameworks [Zn(2)(1,4-bdc)(2)(dabco)] (1), [Zn(2)(1,4-bdc)(tmbdc)(dabco)] (2), [Zn(2)(tmbdc)(2)(dabco)] (3), [Zn(2)(1,4-ndc)(2)(dabco)] (4), [Zn(2)(tfbdc)(2)(dabco)] (5), and [Zn(2)(tmbdc)(2)(bpy)] (8) possess varying size of pores and free apertures originating from the side groups of the 1,4-bdc derivatives. [Zn(2)(1,4-bdc)(2)(bpy)] (6) and [Zn(2)(2,6-ndc)(2)(bpy)] (7) have two- and threefold interpenetrating structures, respectively. The non-interpenetrating frameworks (1-5 and 8) possess surface areas in the range of 1450-2090 m(2)g(-1) and hydrogen sorption capacities of 1.7-2.1 wt % at 78 K and 1 atm. A detailed analysis of the sorption data in conjunction with structural similarities and differences concludes that porous materials with straight channels and large openings do not perform better than those with wavy channels and small openings in terms of hydrogen storage through physisorption.

  13. Method for the continuous fabrication of hydrogen storage alloy negative electrodes

    SciTech Connect

    Wolff, M.; Nuss, M.A.; Fetcenko, M.A.; Lijoi, A.L.

    1989-04-11

    A method is described for substantially continuously fabricating a large area, metal hydride electrochemical hydrogen storage alloy negative electrode for use in a rechargeable nickel-metal hydride battery, the method comprising the steps of: providing a continuous, wire mesh screen substrate; providing a measured amount of powdered metal hydride electrochemical hydrogen storage alloy material; continuously disposing a layer of the hydrogen storage alloy material into contact with the wire mesh screen substrate, in a substantially inert atmosphere; compacting the hydrogen storage alloy material into the wire mesh screen so as to form a green deposit thereof; pre-heating the green deposit of hydrogen storage alloy wire mesh screen; sintering the green deposit of hydrogen storage alloy wire mesh screen in an anhydrous, substantially oxygen free inert atmosphere so as to liberate moisture therefrom; and cooling the sintered hydrogen stage alloy wire mesh screen in a controlled hydrogen atmosphere so as to impart a partial charge thereto.

  14. Homogeneous Catalysis for Sustainable Hydrogen Storage in Formic Acid and Alcohols.

    PubMed

    Sordakis, Katerina; Tang, Conghui; Vogt, Lydia K; Junge, Henrik; Dyson, Paul J; Beller, Matthias; Laurenczy, Gábor

    2017-10-06

    Hydrogen gas is a storable form of chemical energy that could complement intermittent renewable energy conversion. One of the main disadvantages of hydrogen gas arises from its low density, and therefore, efficient handling and storage methods are key factors that need to be addressed to realize a hydrogen-based economy. Storage systems based on liquids, in particular, formic acid and alcohols, are highly attractive hydrogen carriers as they can be made from CO2 or other renewable materials, they can be used in stationary power storage units such as hydrogen filling stations, and they can be used directly as transportation fuels. However, to bring about a paradigm change in our energy infrastructure, efficient catalytic processes that release the hydrogen from these molecules, as well as catalysts that regenerate these molecules from CO2 and hydrogen, are required. In this review, we describe the considerable progress that has been made in homogeneous catalysis for these critical reactions, namely, the hydrogenation of CO2 to formic acid and methanol and the reverse dehydrogenation reactions. The dehydrogenation of higher alcohols available from renewable feedstocks is also described. Key structural features of the catalysts are analyzed, as is the role of additives, which are required in many systems. Particular attention is paid to advances in sustainable catalytic processes, especially to additive-free processes and catalysts based on Earth-abundant metal ions. Mechanistic information is also presented, and it is hoped that this review not only provides an account of the state of the art in the field but also offers insights into how superior catalytic systems can be obtained in the future.

  15. Integrated photoelectrochemical energy storage: solar hydrogen generation and supercapacitor.

    PubMed

    Xia, Xinhui; Luo, Jingshan; Zeng, Zhiyuan; Guan, Cao; Zhang, Yongqi; Tu, Jiangping; Zhang, Hua; Fan, Hong Jin

    2012-01-01

    Current solar energy harvest and storage are so far realized by independent technologies (such as solar cell and batteries), by which only a fraction of solar energy is utilized. It is highly desirable to improve the utilization efficiency of solar energy. Here, we construct an integrated photoelectrochemical device with simultaneous supercapacitor and hydrogen evolution functions based on TiO(2)/transition metal hydroxides/oxides core/shell nanorod arrays. The feasibility of solar-driven pseudocapacitance is clearly demonstrated, and the charge/discharge is indicated by reversible color changes (photochromism). In such an integrated device, the photogenerated electrons are utilized for H(2) generation and holes for pseudocapacitive charging, so that both the reductive and oxidative energies are captured and converted. Specific capacitances of 482 F g(-1) at 0.5 A g(-1) and 287 F g(-1) at 1 A g(-1) are obtained with TiO(2)/Ni(OH)(2) nanorod arrays. This study provides a new research strategy for integrated pseudocapacitor and solar energy application.

  16. Integrated photoelectrochemical energy storage: solar hydrogen generation and supercapacitor

    PubMed Central

    Xia, Xinhui; Luo, Jingshan; Zeng, Zhiyuan; Guan, Cao; Zhang, Yongqi; Tu, Jiangping; Zhang, Hua; Fan, Hong Jin

    2012-01-01

    Current solar energy harvest and storage are so far realized by independent technologies (such as solar cell and batteries), by which only a fraction of solar energy is utilized. It is highly desirable to improve the utilization efficiency of solar energy. Here, we construct an integrated photoelectrochemical device with simultaneous supercapacitor and hydrogen evolution functions based on TiO2/transition metal hydroxides/oxides core/shell nanorod arrays. The feasibility of solar-driven pseudocapacitance is clearly demonstrated, and the charge/discharge is indicated by reversible color changes (photochromism). In such an integrated device, the photogenerated electrons are utilized for H2 generation and holes for pseudocapacitive charging, so that both the reductive and oxidative energies are captured and converted. Specific capacitances of 482 F g−1 at 0.5 A g−1 and 287 F g−1 at 1 A g−1 are obtained with TiO2/Ni(OH)2 nanorod arrays. This study provides a new research strategy for integrated pseudocapacitor and solar energy application. PMID:23248745

  17. Kinetics Study of Solid Ammonia Borane Hydrogen Release – Modeling and Experimental Validation for Chemical Hydrogen Storage

    SciTech Connect

    Choi, Yong-Joon; Ronnebro, Ewa; Rassat, Scot D.; Karkamkar, Abhijeet J.; Maupin, Gary D.; Holladay, Jamelyn D.; Simmons, Kevin L.; Brooks, Kriston P.

    2014-02-24

    Ammonia borane (AB), NH3BH3, is a promising material for chemical hydrogen storage with 19.6 wt% gravimetric hydrogen capacity of which 16.2 wt% hydrogen can be utilized below 200°C. We have investigated the kinetics of hydrogen release from AB and from an AB-methyl cellulose (AB/MC) composite at temperatures of 160-300°C using both experiments and modeling. The purpose of our study was to show safe hydrogen release without thermal runaway effects and to validate system model kinetics. AB/MC released hydrogen at ~20°C lower than neat AB and at a rate that is two times faster. Based on the experimental results, the kinetics equations were revised to better represent the growth and nucleation process during decomposition of AB. We explored two different reactor concepts; Auger and fixed bed. The current Auger reactor concept turned out to not be appropriate, however, we demonstrated safe self-propagation of the hydrogen release reaction of solid AB/MC in a fixed bed reactor.

  18. The Current Status of Hydrogen Storage Alloy Development for Electrochemical Applications

    PubMed Central

    Young, Kwo-hsiung; Nei, Jean

    2013-01-01

    In this review article, the fundamentals of electrochemical reactions involving metal hydrides are explained, followed by a report of recent progress in hydrogen storage alloys for electrochemical applications. The status of various alloy systems, including AB5, AB2, A2B7-type, Ti-Ni-based, Mg-Ni-based, BCC, and Zr-Ni-based metal hydride alloys, for their most important electrochemical application, the nickel metal hydride battery, is summarized. Other electrochemical applications, such as Ni-hydrogen, fuel cell, Li-ion battery, air-metal hydride, and hybrid battery systems, also have been mentioned. PMID:28788349

  19. The Current Status of Hydrogen Storage Alloy Development for Electrochemical Applications.

    PubMed

    Young, Kwo-Hsiung; Nei, Jean

    2013-10-17

    In this review article, the fundamentals of electrochemical reactions involving metal hydrides are explained, followed by a report of recent progress in hydrogen storage alloys for electrochemical applications. The status of various alloy systems, including AB₅, AB₂, A₂B₇-type, Ti-Ni-based, Mg-Ni-based, BCC, and Zr-Ni-based metal hydride alloys, for their most important electrochemical application, the nickel metal hydride battery, is summarized. Other electrochemical applications, such as Ni-hydrogen, fuel cell, Li-ion battery, air-metal hydride, and hybrid battery systems, also have been mentioned.

  20. Theory, synthesis and characterization of nano-scale architectures for solid-state hydrogen storage

    NASA Astrophysics Data System (ADS)

    Miller, Michael A.

    Traditional materials discovery and development techniques have not yet yielded the necessary breakthroughs needed for practical utilization of hydrogen storage. An integrated theoretical-experimental approach to the development of novel materials capable of hydrogen storage under the narrow thermodynamic regime suitable for automotive applications is undertaken. The viability of engineering two-part nano-architectures (heterostructures) to enhance the binding energy between molecular hydrogen and solid-state nanostructures, or to evince dissociation and uptake of hydrogen into the architecture, was explored. First, exceptional hydrogen uptake (7.5 wt.%) was validated in a metal organic framework compound, MOF-177, at low temperature (77 K), and a thermodynamic model for physisorption was established as a benchmark for all such structures. A chemisorptive pathway for enhanced hydrogen uptake (2.2 wt.%) at room temperature in heterostructures of metal-organic-frameworks (MOFs), via a mechanism now referred to as hydrogen spillover, was experimentally validated and further studied through computations. Ab initio computations at the level of Hartree-Fock (HF) and density functional theories (DFT) made it possible to calculate the thermochemical properties of hydrogen uptake in Pt-doped MOF heterostructures, which verified the thermodynamic plausibility of hydrogen spillover. Furthermore, the hydrogen spillover mechanism was successfully elicited from heterostructures consisting of metal-doped carbon materials, which yielded the highest uptake of hydrogen ever measured at room temperature (8.0 wt.%) for carbon-based material. The theoretical foundation was formed for a new way of considering how binding interactions between small molecules, such as dihydrogen, and an engineered surface may be influenced by coupling molecular vibrations with low-frequency surface plasmons in clusters of a metal compound. Finally, new MOF-based heterostructures in which a metal dopant is

  1. Carbide-Derived Carbons with Tunable Porosity Optimized for Hydrogen Storage

    SciTech Connect

    Fisher, John E.; Gogotsi, Yury; Yildirim, Taner

    2010-01-07

    On-board hydrogen storage is a key requirement for fuel cell-powered cars and trucks. Porous carbon-based materials can in principle adsorb more hydrogen per unit weight at room temperature than liquid hydrogen at -176 oC. Achieving this goal requires interconnected pores with very high internal surface area, and binding energies between hydrogen and carbon significantly enhanced relative to H2 on graphite. In this project a systematic study of carbide-derived carbons, a novel form of porous carbon, was carried out to discover a high-performance hydrogen sorption material to meet the goal. In the event we were unable to improve on the state of the art in terms of stored hydrogen per unit weight, having encountered the same fundamental limit of all porous carbons: the very weak interaction between H2 and the carbon surface. On the other hand we did discover several strategies to improve storage capacity on a volume basis, which should be applicable to other forms of porous carbon. Further discoveries with potentially broader impacts include • Proof that storage performance is not directly related to pore surface area, as had been previously claimed. Small pores (< 1.5 nm) are much more effective in storing hydrogen than larger ones, such that many materials with large total surface areas are sub-par performers. • Established that the distribution of pore sizes can be controlled during CDC synthesis, which opens the possibility of developing high performance materials within a common family while targeting widely disparate applications. Examples being actively pursued with other funding sources include methane storage, electrode materials for batteries and supercapacitors with record high specific capacitance, and perm-selective membranes which bind cytokines for control of infections and possibly hemodialysis filters.

  2. Development of the ReaxFFCBN reactive force field for the improved design of liquid CBN hydrogen storage materials.

    PubMed

    Pai, Sung Jin; Yeo, Byung Chul; Han, Sang Soo

    2016-01-21

    Liquid CBN (carbon-boron-nitrogen) hydrogen-storage materials such as 3-methyl-1,2-BN-cyclopentane have the advantage of being easily accessible for use in current liquid-fuel infrastructure. To develop practical liquid CBN hydrogen-storage materials, it is of great importance to understand the reaction pathways of hydrogenation/dehydrogenation in the liquid phase, which are difficult to discover by experimental methods. Herein, we developed a reactive force field (ReaxFFCBN) from quantum mechanical (QM) calculations based on density functional theory for the storage of hydrogen in BN-substituted cyclic hydrocarbon materials. The developed ReaxFFCBN provides similar dehydrogenation pathways and energetics to those predicted by QM calculations. Moreover, molecular dynamics (MD) simulations with the developed ReaxFFCBN can predict the stability and dehydrogenation behavior of various liquid CBN hydrogen-storage materials. Our simulations reveal that a unimolecular dehydrogenation mechanism is preferred in liquid CBN hydrogen-storage materials. However, as the temperature in the simulation increases, the contribution of a bimolecular dehydrogenation mechanism also increases. Moreover, our ReaxFF MD simulations show that in terms of thermal stability and dehydrogenation kinetics, liquid CBN materials with a hexagonal structure are more suitable materials than those with a pentagonal structure. We expect that the developed ReaxFFCBN could be a useful protocol in developing novel liquid CBN hydrogen-storage materials.

  3. Accelerating the Understanding and Development of Hydrogen Storage Materials: A Review of the Five-Year Efforts of the Three DOE Hydrogen Storage Materials Centers of Excellence

    NASA Astrophysics Data System (ADS)

    Klebanoff, Leonard E.; Ott, Kevin C.; Simpson, Lin J.; O'Malley, Kathleen; Stetson, Ned T.

    2014-06-01

    A technical review of the progress achieved in hydrogen storage materials development through the U.S. Department of Energy's (DOE) Fuel Cell Technologies Office and the three Hydrogen Storage Materials Centers of Excellence (CoEs), which ran from 2005 to 2010 is presented. The three CoEs were created to develop reversible metal hydrides, chemical hydrogen storage materials, and high-specific-surface-area (SSA) hydrogen sorbents. For each CoE, the approach taken is specified, key outcomes and accomplishments identified, and recommendations for future work are suggested. The Metal Hydride Center of Excellence addresses work on destabilized hydrides, including the LiBH/Mg2NiH4 system, borohydrides, amides, and alanes; and compares the best materials to DOE targets. The Chemical Hydrogen Storage Center of Excellence discusses the classes of materials studied for chemical hydrogen storage, focusing on ammonia borane and examines the progress in developing efficient regeneration schemes. The Hydrogen Sorption Center of Excellence describes the progress in developing high-SSA sorbents and pathways for developing improved materials capable of achieving DOE targets. The phenomenon of spillover is also observed and its importance to ensuring improved measurements is discussed. Through the five-year effort of the Hydrogen Storage Materials Centers of Excellence, significant progress was achieved in developing and understanding hydrogen storage materials.

  4. First-Principles Study of Carbon Nanoframeworks Tailored for Hydrogen Storage

    NASA Astrophysics Data System (ADS)

    Kim, Eunja; Weck, Philippe; Naduvalath, Balakrishnan; Cheng, Hansong; Yakobson, Boris

    2008-03-01

    Based on first-principles calculations, we propose a novel class of 3-D materials consisting of small diameter single-walled carbon nanotubes (SWCNTs) functionalized by organic ligands as potential hydrogen storage media. Specifically, we have carried out density functional theory calculations to determine the stable structures and properties of nanoframeworks consisting of (5,0) and (3,3) SWCNTs constrained by phenyl spacers. Valence and conduction properties, as well as normal modes, of pristine nanotubes are found to change significantly upon functionalization, in a way that can serve as experimental diagnostics of the successful synthesis of the proposed framework structures. Ab initio molecular dynamics simulations indicate that such systems are thermodynamically stable for on-board hydrogen storage. In order to increase the hydrogen uptake in the interstitial cavity of such nanoframeworks, we are currently investigating the possibility of Li deposition on these nanostructures.

  5. Lithium-decorated oxidized graphyne for hydrogen storage by first principles study

    SciTech Connect

    Yan, Zeyu; Wang, Lang; Cheng, Julong; Huang, Libei; Zhu, Chao; Chen, Chi; Miao, Ling Jiang, Jianjun

    2014-11-07

    The geometric stability and hydrogen storage capacity of Li decorated oxidized γ-graphyne are studied based on the first-principles calculations. It is found that oxygen atoms trend to bond with acetylenic carbons and form C=O double bonds on both sides of graphyne. The binding energy of single Li atom on oxidized graphyne is 3.29 eV, owning to the strong interaction between Li atom and O atom. Meanwhile, the dispersion of Li is stable even under a relatively high density. One attached Li atom can at least adsorb six hydrogen molecules around. Benefitting from the porous structure of graphyne and the high attached Li density, a maximum hydrogen storage density 12.03 wt. % is achieved with four Li atoms in graphyne cell. The corresponding average binding energy is 0.24 eV/H{sub 2}, which is suitable for reversible storage. These results indicate that Li decorated graphyne can serve as a promising hydrogen storage material.

  6. Combining computation and experiment to accelerate the discovery of new hydrogen storage materials

    NASA Astrophysics Data System (ADS)

    Siegel, Donald

    2009-03-01

    The potential of emerging technologies such as fuel cells (FCs) and photovoltaics for environmentally-benign power generation has sparked renewed interest in the development of novel materials for high density energy storage. For applications in the transportation sector, the demands placed upon energy storage media are especially stringent, as a potential replacement for fossil-fuel-powered internal combustion engines -- namely, the proton exchange membrane FC -- utilizes hydrogen as a fuel. Although hydrogen has about three times the energy density of gasoline by weight, its volumetric energy density (even at 700 bar) is roughly a factor of six smaller. Consequently, the safe and efficient storage of hydrogen has been identified as one of the key materials-based challenges to realizing a transition to FC vehicles. This talk will present an overview of recent efforts at Ford aimed at developing new materials for reversible, solid state hydrogen storage. A tight coupling between first-principles modeling and experiments has greatly accelerated our efforts, and several examples illustrating the benefits of this approach will be presented.

  7. Sc-Decorated Porous Graphene for High-Capacity Hydrogen Storage: First-Principles Calculations

    PubMed Central

    Chen, Yuhong; Wang, Jing; Yuan, Lihua; Zhang, Meiling

    2017-01-01

    The generalized gradient approximation (GGA) function based on density functional theory is adopted to investigate the optimized geometrical structure, electron structure and hydrogen storage performance of Sc modified porous graphene (PG). It is found that the carbon ring center is the most stable adsorbed position for a single Sc atom on PG, and the maximum number of adsorbed H2 molecules is four with the average adsorption energy of −0.429 eV/H2. By adding a second Sc atom on the other side of the system, the hydrogen storage capacity of the system can be improved effectively. Two Sc atoms located on opposite sides of the PG carbon ring center hole is the most suitable hydrogen storage structure, and the hydrogen storage capacity reach a maximum 9.09 wt % at the average adsorption energy of −0.296 eV/H2. The adsorption of H2 molecules in the PG system is mainly attributed to orbital hybridization among H, Sc, and C atoms, and Coulomb attraction between negatively charged H2 molecules and positively charged Sc atoms. PMID:28767084

  8. Sc-Decorated Porous Graphene for High-Capacity Hydrogen Storage: First-Principles Calculations.

    PubMed

    Chen, Yuhong; Wang, Jing; Yuan, Lihua; Zhang, Meiling; Zhang, Cairong

    2017-08-02

    The generalized gradient approximation (GGA) function based on density functional theory is adopted to investigate the optimized geometrical structure, electron structure and hydrogen storage performance of Sc modified porous graphene (PG). It is found that the carbon ring center is the most stable adsorbed position for a single Sc atom on PG, and the maximum number of adsorbed H₂ molecules is four with the average adsorption energy of -0.429 eV/H₂. By adding a second Sc atom on the other side of the system, the hydrogen storage capacity of the system can be improved effectively. Two Sc atoms located on opposite sides of the PG carbon ring center hole is the most suitable hydrogen storage structure, and the hydrogen storage capacity reach a maximum 9.09 wt % at the average adsorption energy of -0.296 eV/H₂. The adsorption of H₂ molecules in the PG system is mainly attributed to orbital hybridization among H, Sc, and C atoms, and Coulomb attraction between negatively charged H₂ molecules and positively charged Sc atoms.

  9. 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.

  10. Technical assessment of compressed hydrogen storage tank systems for automotive applications.

    SciTech Connect

    Hua, T. Q.; Ahluwalia, R. K.; Peng, J. K.; Kromer, M.; Lasher, S.; McKenney, K.; Law, K.; Sinha, J.

    2011-02-09

    The performance and cost of compressed hydrogen storage tank systems has been assessed and compared to the U.S. Department of Energy (DOE) 2010, 2015, and ultimate targets for automotive applications. The on-board performance and high-volume manufacturing cost were determined for compressed hydrogen tanks with design pressures of 350 bar ({approx}5000 psi) and 700 bar ({approx}10,000 psi) capable of storing 5.6 kg of usable hydrogen. The off-board performance and cost of delivering compressed hydrogen was determined for hydrogen produced by central steam methane reforming (SMR). The main conclusions of the assessment are that the 350-bar compressed storage system has the potential to meet the 2010 and 2015 targets for system gravimetric capacity but will not likely meet any of the system targets for volumetric capacity or cost, given our base case assumptions. The 700-bar compressed storage system has the potential to meet only the 2010 target for system gravimetric capacity and is not likely to meet any of the system targets for volumetric capacity or cost, despite the fact that its volumetric capacity is much higher than that of the 350-bar system. Both the 350-bar and 700-bar systems come close to meeting the Well-to-Tank (WTT) efficiency target, but fall short by about 5%. These results are summarized.

  11. Catalyzed light hydride nanomaterials embedded in a micro-channels hydrogen storage container.

    PubMed

    Dehouche, Zahir; Peretti, Hernán A; Yoo, Yeong; Belkacemi, Khaled; Goyette, Jacques

    2009-01-01

    Activated alloys synthesized by arc-melting were examined as catalysts for improving the hydrogen sorption characteristics of nanostructured magnesium hydride, proposed as a reversible hydrogen storage material. The MgH(2)-catalyst absorbing materials were prepared by ball milling of pure MgH(2) with hydrided Zr(47)Ni(53), Zr(9)Ni(11), and other alloys investigated. The nanostructured MgH(2)-intermetallic systems were tested at 250 degrees C and catalyst addition of eutectoid Zr(47)Ni(53) resulted in the fastest desorption time and highest initial desorption rate. The catalyzed Mg-hydride with activated Zr(9)Ni(11) and Zr(7)Ni(10) phases showed fast desorption kinetics. Moreover, the results demonstrated that the composition of dispersed Zr(x)Ni(y)catalysts has a strong influence on the amount of accumulated hydrogen and desorption rate of Mg-nanocomposite. Part two covers advanced micro-channels hydrogen storage module design based on the results of semi-empirical computer simulations of heat and mass transfers in the container. The micro-channels reservoir concept offers many advantages over the conventional metal hydride hydrogen storage system. It is a micro-structured system that can pack a lot of power into a small space and dissipate effectively the heat of the sorption reactions. This review summarizes recent patents related to CNTS.

  12. Recommended volumetric capacity definitions and protocols for accurate, standardized and unambiguous metrics for hydrogen storage materials

    NASA Astrophysics Data System (ADS)

    Parilla, Philip A.; Gross, Karl; Hurst, Katherine; Gennett, Thomas

    2016-03-01

    The ultimate goal of the hydrogen economy is the development of hydrogen storage systems that meet or exceed the US DOE's goals for onboard storage in hydrogen-powered vehicles. In order to develop new materials to meet these goals, it is extremely critical to accurately, uniformly and precisely measure materials' properties relevant to the specific goals. Without this assurance, such measurements are not reliable and, therefore, do not provide a benefit toward the work at hand. In particular, capacity measurements for hydrogen storage materials must be based on valid and accurate results to ensure proper identification of promising materials for further development. Volumetric capacity determinations are becoming increasingly important for identifying promising materials, yet there exists controversy on how such determinations are made and whether such determinations are valid due to differing methodologies to count the hydrogen content. These issues are discussed herein, and we show mathematically that capacity determinations can be made rigorously and unambiguously if the constituent volumes are well defined and measurable in practice. It is widely accepted that this occurs for excess capacity determinations and we show here that this can happen for the total capacity determination. Because the adsorption volume is undefined, the absolute capacity determination remains imprecise. Furthermore, we show that there is a direct relationship between determining the respective capacities and the calibration constants used for the manometric and gravimetric techniques. Several suggested volumetric capacity figure-of-merits are defined, discussed and reporting requirements recommended. Finally, an example is provided to illustrate these protocols and concepts.

  13. Vehicular Storage of Hydrogen in Insulated Pressure Vessels

    SciTech Connect

    Aceves, S M; Berry, G D; Martinez-Frias, J; Espinosa-Loza, F

    2005-01-03

    This paper describes the development of an alternative technology for storing hydrogen fuel onboard automobiles. Insulated pressure vessels are cryogenic-capable pressure vessels that can accept cryogenic liquid fuel, cryogenic compressed gas or compressed gas at ambient temperature. Insulated pressure vessels offer advantages over conventional H{sub 2} storage approaches. Insulated pressure vessels are more compact and require less carbon fiber than GH{sub 2} vessels. They have lower evaporative losses than LH{sub 2} tanks, and are much lighter than metal hydrides. After outlining the advantages of hydrogen fuel and insulated pressure vessels, the paper describes the experimental and analytical work conducted to verify that insulated pressure vessels can be used safely for vehicular H{sub 2} storage. The paper describes tests that have been conducted to evaluate the safety of insulated pressure vessels. Insulated pressure vessels have successfully completed a series of DOT, ISO and SAE certification tests. A draft procedure for insulated pressure vessel certification has been generated to assist in a future commercialization of this technology. An insulated pressure vessel has been installed in a hydrogen fueled truck and it is currently being subjected to extensive testing.

  14. Role of exposed metal sites in hydrogen storage in MOFs.

    PubMed

    Vitillo, Jenny G; Regli, Laura; Chavan, Sachin; Ricchiardi, Gabriele; Spoto, Giuseppe; Dietzel, Pascal D C; Bordiga, Silvia; Zecchina, Adriano

    2008-07-02

    The role of exposed metal sites in increasing the H2 storage performances in metal-organic frameworks (MOFs) has been investigated by means of IR spectrometry. Three MOFs have been considered: MOF-5, with unexposed metal sites, and HKUST-1 and CPO-27-Ni, with exposed Cu(2+) and Ni(2+), respectively. The onset temperature of spectroscopic features associated with adsorbed H2 correlates with the adsorption enthalpy obtained by the VTIR method and with the shift experienced by the H-H stretching frequency. This relationship can be ascribed to the different nature and accessibility of the metal sites. On the basis of a pure energetic evaluation, it was observed that the best performance was shown by CPO-27-Ni that exhibits also an initial adsorption enthalpy of -13.5 kJ mol(-1), the highest yet observed for a MOF. Unfortunately, upon comparison of the hydrogen amounts stored at high pressure, the hydrogen capacities in these conditions are mostly dependent on the surface area and total pore volume of the material. This means that if control of MOF surface area can benefit the total stored amounts, only the presence of a great number of strong adsorption sites can make the (P, T) storage conditions more economically favorable. These observations lead to the prediction that efficient H2 storage by physisorption can be obtained by increasing the surface density of strong adsorption sites.

  15. Methyllithium-Doped Naphthyl-Containing Conjugated Microporous Polymer with Enhanced Hydrogen Storage Performance.

    PubMed

    Xu, Dan; Sun, Lei; Li, Gang; Shang, Jin; Yang, Rui-Xia; Deng, Wei-Qiao

    2016-06-01

    Hydrogen storage is a primary challenge for using hydrogen as a fuel. With ideal hydrogen storage kinetics, the weak binding strength of hydrogen to sorbents is the key barrier to obtain decent hydrogen storage performance. Here, we reported the rational synthesis of a methyllithium-doped naphthyl-containing conjugated microporous polymer with exceptional binding strength of hydrogen to the polymer guided by theoretical simulations. Meanwhile, the experimental results showed that isosteric heat can reach up to 8.4 kJ mol(-1) and the methyllithium-doped naphthyl-containing conjugated microporous polymer exhibited an enhanced hydrogen storage performance with 150 % enhancement compared with its counterpart naphthyl-containing conjugated microporous polymer. These results indicate that this strategy provides a direction for design and synthesis of new materials that meet the US Department of Energy (DOE) hydrogen storage target. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Hydrogen Storage in the Carbon Dioxide - Formic Acid Cycle.

    PubMed

    Fink, Cornel; Montandon-Clerc, Mickael; Laurenczy, Gabor

    2015-01-01

    This year Mankind will release about 39 Gt carbon dioxide into the earth's atmosphere, where it acts as a greenhouse gas. The chemical transformation of carbon dioxide into useful products becomes increasingly important, as the CO(2) concentration in the atmosphere has reached 400 ppm. One approach to contribute to the decrease of this hazardous emission is to recycle CO(2), for example reducing it to formic acid. The hydrogenation of CO(2) can be achieved with a series of catalysts under basic and acidic conditions, in wide variety of solvents. To realize a hydrogen-based charge-discharge device ('hydrogen battery'), one also needs efficient catalysts for the reverse reaction, the dehydrogenation of formic acid. Despite of the fact that the overwhelming majority of these reactions are carried out using precious metals-based catalysts (mainly Ru), we review here developments for catalytic hydrogen evolution from formic acid with iron-based complexes.

  17. Hydrogen Storage at Ambient Temperature by the Spillover Mechanism

    SciTech Connect

    Yang , Ralph T.

    2011-02-04

    The goal of this project was to develop new nanostructured sorbent materials, using the hydrogen spillover mechanism that could meet the DOE 2010 system targets for on-board vehicle hydrogen storage. Hydrogen spillover may be broadly defined as the transport (i.e., via surface diffusion) of dissociated hydrogen adsorbed or formed on a first surface onto another surface. The first surface is typically a metal (that dissociates H2) and the second surface is typically the support on which the metal is doped. Hydrogen spillover is a well documented phenomenon in the catalysis literature, and has been known in the catalysis community for over four decades, although it is still not well understood.1, 2 Much evidence has been shown in the literature on its roles played in catalytic reactions. Very little has been studied on hydrogen storage by spillover at ambient temperature. However, it is also known to occur at such temperature, e.g., direct evidence has been shown for spillover on commercial fuel-cell, highly dispersed Pt/C, Ru/C and PtRu/C catalysts by inelastic neutron scattering.3 To exploit spillover for storage, among the key questions are whether spillover is reversible at ambient temperature and if the adsorption (refill) and desorption rates at ambient temperature are fast enough for automotive applications. In this project, we explored new sorbents by using a transition metal (e.g., Pt, Ru, Pd and Ni) as the H2 dissociation source and sorbents as the hydrogen receptor. The receptors included superactivated carbons (AX-21 and Maxsorb), metal organic frameworks (MOFs) and zeolites. Different metal doping methods have been used successfully to achieve high metal dispersion thereby allowing significant spillover enhancements, as well as a bridging technique used for bridging to MOFs. Among the metals tested, Pt is the hardest to achieve high metal dispersion (and consequently spillover) while Ru is the easiest to disperse. By properly dispersing Pt on

  18. Destabilized and catalyzed borohydride for reversible hydrogen storage

    DOEpatents

    Mohtadi, Rana F [Northville, MI; Zidan, Ragaiy [Aiken, SC; Gray, Joshua [Aiken, SC; Stowe, Ashley C [Knoxville, TN; Sivasubramanian, Premkumar [Aiken, SC

    2012-02-28

    A process of forming a hydrogen storage material, including the steps of: providing a borohydride material of the formula: M(BH.sub.4).sub.x where M is an alkali metal or an alkaline earth metal and 1.ltoreq.x.ltoreq.2; providing an alanate material of the formula: M.sub.1(AlH.sub.4).sub.x where M.sub.1 is an alkali metal or an alkaline earth metal and 1.ltoreq.x.ltoreq.2; providing a halide material of the formula: M.sub.2Hal.sub.x where M.sub.2 is an alkali metal, an alkaline earth metal or transition metal and Hal is a halide and 1.ltoreq.x.ltoreq.4; combining the borohydride, alanate and halide materials such that 5 to 50 molar percent from the borohydride material is present forming a reaction product material having a lower hydrogen release temperature than the alanate material.

  19. Hydrogen Trailer Storage Facility (Building 878). Consequence analysis

    SciTech Connect

    Banda, Z.; Wood, C.L.

    1994-12-01

    The Department of Energy Order 5500.3A requires facility-specific hazards assessments be prepared, maintained, and used for emergency planning purposes. This consequence analysis documents the impact that a hydrogen accident could have to employees, the general public, and nearby facilities. The computer model ARCHIE was utilized to determine discharge rates, toxic vapor dispersion analyses, flammable vapor cloud hazards, explosion hazards, and flame jets for the Hydrogen Trailer Storage Facility located at Building 878. To determine over pressurization effects, hand calculations derived from the Department of the Air Force Manual, ``Structures to Resist the Effects of Accidental Explosions,`` were utilized. The greatest distances at which a postulated facility event will produce the Lower Flammability and the Lower Detonation Levels are 1,721 feet and 882 feet, respectively. The greatest distance at which 10.0 psi overpressure (i.e., total building destruction) is reached is 153 feet.

  20. Modified lithium borohydrides for reversible hydrogen storage (2).

    PubMed

    Au, Ming; Jurgensen, Arthur; Zeigler, Kristine

    2006-12-28

    This paper reports the results of the effort to destabilize lithium borohydride for reversible hydrogen storage. Various metals, metal hydrides, and metal chlorides were selected and evaluated as destabilization agents for reducing dehydriding temperatures and improving dehydriding/rehydriding reversibility. The most effective material was LiBH4 + 0.2MgCl2 + 0.1TiCl3 which starts desorbing 5 wt % of hydrogen at 60 degrees C and can be rehydrogenated to 4.5 wt % at 600 degrees C and 70 bar. X-ray diffraction and Raman spectroscopic analysis show the interaction of LiBH4 with additives and the unusual change of B-H stretching.

  1. Electrochemical hydrogen storage in single-walled carbon nanotube paper.

    PubMed

    Guo, Z P; Ng, S H; Wang, J Z; Huang, Z G; Liu, H K; Too, C O; Wallace, G G

    2006-03-01

    Single-walled carbon nanotube (SWNT) papers were successfully prepared by dispersing SWNTs in Triton X-100 solution, then filtered by PVDF membrane (0.22 microm pore size). The electrochemical behavior and the reversible hydrogen storage capacity of single-walled carbon nanotube (SWNT) papers have been investigated in alkaline electrolytic solutions (6 N KOH) by cyclic voltammetry, linear micropolarization, and constant current charge/discharge measurements. The effect of thickness and the addition of carbon black on hydrogen adsorption/desorption were also investigated. It was found that the electrochemical charge-discharge mechanism occurring in SWNT paper electrodes is somewhere between that of carbon nanotubes (physical process) and that of metal hydride electrodes (chemical process), and consists of a charge-transfer reaction (Reduction/Oxidation) and a diffusion step (Diffusion).

  2. Enhancement of Hydrogen Storage Capacity in Hydrate Lattices

    SciTech Connect

    Yoo, Soohaeng; Xantheas, Sotiris S.

    2012-02-16

    First principles electronic structure calculations of the gas phase pentagonal dodecahedron (H2O)20 (D-cage) and tetrakaidecahedron (H2O)24 (T-cage), which are building blocks of structure I (sI) hydrate lattice, suggest that these can accommodate up to a maximum of 5 and 7 guest hydrogen molecules, respectively. For the pure hydrogen hydrate, Born-Oppenheimer Molecular Dynamics (BOMD) simulations of periodic (sI) hydrate lattices indicate that the guest molecules are released into the vapor phase via the hexagonal phases of the larger T-cages. An additional mechanism for the migration between neighboring D- and T-cages was found to occur through a shared pentagonal face via the breaking and reforming of a hydrogen bond. This molecular mechanism is also found for the expulsion of a CH4 molecule from the D-cage. The presence of methane in the larger T-cages was found to block this release, therefore suggesting possible scenarios for the stabilization of these mixed guest clathrate hydrates and the potential enhancement of their hydrogen storage capacity.

  3. Inorganic Chemistry in Hydrogen Storage and Biomass Catalysis

    SciTech Connect

    Thorn, David

    2012-06-13

    Making or breaking C-H, B-H, C-C bonds has been at the core of catalysis for many years. Making or breaking these bonds to store or recover energy presents us with fresh challenges, including how to catalyze these transformations in molecular systems that are 'tuned' to minimize energy loss and in molecular and material systems present in biomass. This talk will discuss some challenging transformations in chemical hydrogen storage, and some aspects of the inorganic chemistry we are studying in the development of catalysts for biomass utilization.

  4. Reversible transient hydrogen storage in a fuel cell-supercapacitor hybrid device.

    PubMed

    Unda, Jesus E Zerpa; Roduner, Emil

    2012-03-21

    A new concept is investigated for hydrogen storage in a supercapacitor based on large-surface-area carbon material (Black Pearls 2000). Protons and electrons of hydrogen are separated on a fuel cell-type electrode and then stored separately in the electrical double layer, the electrons on the carbon and the protons in the aqueous electrolyte of the supercapacitor electrode. The merit of this concept is that it works spontaneously and reversibly near ambient pressure and temperature. This is in pronounced contrast to what has been known as electrochemical hydrogen storage, which does not involve hydrogen gas and where electrical work has to be spent in the loading process. With the present hybrid device, a H(2) storage capacity of 0.13 wt% was obtained, one order of magnitude more than what can be stored by conventional physisorption on large-surface-area carbons at the same pressure and temperature. Raising the pressure from 1.5 to 3.5 bar increased the capacity by less than 20%, indicating saturation. A capacitance of 11 μF cm(-2), comparable with that of a commercial double layer supercapacitor, was found using H(2)SO(4) as electrolyte. The chemical energy of the stored H(2) is almost a factor of 3 larger than the electrical energy stored in the supercapacitor. Further developments of this concept relate to a hydrogen buffer integrated inside a proton exchange membrane fuel cell to be used in case of peak power demand. This serial setup takes advantage of the suggested novel concept of hydrogen storage. It is fundamentally different from previous ways of operating a conventional supercapacitor hooked up in parallel to a fuel cell.

  5. NASA Hydrogen Research for Spaceport and Space Based Applications

    NASA Technical Reports Server (NTRS)

    Anderson, Tim

    2006-01-01

    The activities presented are a broad based approach to advancing key hydrogen related technologies in areas such as hydrogen production, distributed sensors for hydrogen-leak detection, laser instrumentation for hydrogen-leak detection, and cryogenic transport and storage. Presented are the results form 15 research projects, education, and outreach activities, system and trade studies, and project management. The work will aid in advancing the state-of-the-art for several critical technologies related to the implementation of a hydrogen infrastructure. Activities conducted are relevant to a number of propulsion and power systems for terrestrial, aeronautics, and aerospace applications.

  6. Hydrogen-Resistant Fe/Ni/Cr-Base Superalloy

    NASA Technical Reports Server (NTRS)

    Bhat, Biliyar N.; Chen, Po-Shou; Panda, Binayak

    1994-01-01

    Strong Fe/Ni/Cr-base hydrogen- and corrosion-resistant alloy developed. Superalloy exhibits high strength and exceptional resistance to embrittlement by hydrogen. Contains two-phase microstructure consisting of conductivity precipitated phase in conductivity matrix phase. Produced in wrought, weldable form and as castings, alloy maintains high ductility and strength in air and hydrogen. Strength exceeds previously known Fe/Cr/Ni hydrogen-, oxidation-, and corrosion-resistant alloys. Provides higher strength-to-weight ratios for lower weight in applications as storage vessels and pipes that must contain hydrogen.

  7. Can Silicon Carbide Nanotubes Be Effective Storage Medium for Hydrogen Storage

    NASA Astrophysics Data System (ADS)

    Mukherjee, Souptik; Ray, Asok

    2009-03-01

    A systematic study of molecular hydrogen adsorption on three different atomic configurations of armchair SICNTs has been performed. In the first stage of our study, first principles calculations using both density functional theory (DFT) and hybrid density functional theory (HDFT) as well as the finite cluster approximation have been performed to study the adsorption of molecular hydrogen on three types of armchair (9, 9) silicon carbide nanotubes. The distances of molecular hydrogen from the outer wall of the nanotubes have been optimized manually using the B3LYP and PW91 functionals and results have been compared in detail with published literature results. In the second part of our study, hydrogen molecule has been adsorbed from both inside as well as from the outer wall of nanotubes ranging from (3, 3) to (6, 6) for all three types. A detailed comparison of the binding energies, equilibrium positions and Mulliken charges has been performed for all three types of nanotubes and for all possible sites in those nanotubes. In the third phase, co-adsorption of two hydrogen molecules has been carried out. Possibilities of hydrogen storage have been explored in detail.

  8. First Principles Simulations of Hydrogen Storage via Spillover in MOF-5

    NASA Astrophysics Data System (ADS)

    Siegel, Donald

    2010-03-01

    Metal organic frameworks (MOF) have attracted considerable attention as hydrogen storage materials due to their high surface areas and ability to adsorb large quantities of hydrogen by weight (˜12 wt. % at 100bar). However, as a consequence of the weak H2-MOF bonding interaction (˜5 kJ/mol H2), this uptake occurs only at cryogenic temperatures; at room temperature, gravimetric capacities do not exceed ˜0.5 wt. %. As an ideal storage system would operate under ambient conditions, renewed interest in these materials has been sparked by recent experiments demonstrating RT uptake of ˜4 wt. % via the so-called ``spillover'' mechanism [JACS 128, 8136 (2006)]. In contrast to the conventional mechanism of MOF-based storage, where molecular H2 bonds directly to the MOF, spillover employs a hydrogen dissociation catalyst to generate atomic hydrogen (H), presumably resulting in stronger H-MOF bonding. Recent computational studies of spillover have reported conflicting results regarding the nature of this interaction. In an effort to resolve these ambiguities and clarify the thermodynamics of MOF-based spillover, DFT calculations are used to evaluate binding energies for several H adsorption configurations on MOF-5. Importantly, our calculations avoid the cluster approximation to the MOF geometry--a source of significant uncertainty in previous studies--and account for finite-temperature contributions to the free energy of adsorption.

  9. Hydrogen-Bromine Flow Battery: Hydrogen Bromine Flow Batteries for Grid Scale Energy Storage

    SciTech Connect

    2010-10-01

    GRIDS Project: LBNL is designing a flow battery for grid storage that relies on a hydrogen-bromine chemistry which could be more efficient, last longer and cost less than today’s lead-acid batteries. Flow batteries are fundamentally different from traditional lead-acid batteries because the chemical reactants that provide their energy are stored in external tanks instead of inside the battery. A flow battery can provide more energy because all that is required to increase its storage capacity is to increase the size of the external tanks. The hydrogen-bromine reactants used by LBNL in its flow battery are inexpensive, long lasting, and provide power quickly. The cost of the design could be well below $100 per kilowatt hour, which would rival conventional grid-scale battery technologies.

  10. Simple and Efficient System for Combined Solar Energy Harvesting and Reversible Hydrogen Storage.

    PubMed

    Li, Lu; Mu, Xiaoyue; Liu, Wenbo; Mi, Zetian; Li, Chao-Jun

    2015-06-24

    Solar energy harvesting and hydrogen economy are the two most important green energy endeavors for the future. However, a critical hurdle to the latter is how to safely and densely store and transfer hydrogen. Herein, we developed a reversible hydrogen storage system based on low-cost liquid organic cyclic hydrocarbons at room temperature and atmospheric pressure. A facile switch of hydrogen addition (>97% conversion) and release (>99% conversion) with superior capacity of 7.1 H2 wt % can be quickly achieved over a rationally optimized platinum catalyst with high electron density, simply regulated by dark/light conditions. Furthermore, the photodriven dehydrogenation of cyclic alkanes gave an excellent apparent quantum efficiency of 6.0% under visible light illumination (420-600 nm) without any other energy input, which provides an alternative route to artificial photosynthesis for directly harvesting and storing solar energy in the form of chemical fuel.

  11. Key study on the potential of hydrazine bisborane for solid- and liquid-state chemical hydrogen storage.

    PubMed

    Pylypko, Sergii; Petit, Eddy; Yot, Pascal G; Salles, Fabrice; Cretin, Marc; Miele, Philippe; Demirci, Umit B

    2015-05-04

    Hydrazine bisborane N2H4(BH3)2 (HBB; 16.8 wt %) recently re-emerged as a potential hydrogen storage material. However, such potential is controversial: HBB was seen as a hazardous compound up to 2010, but now it would be suitable for hydrogen storage. In this context, we focused on fundamentals of HBB because they are missing in the literature and should help to shed light on its effective potential while taking into consideration any risk. Experimental/computational methods were used to get a complete characterization data sheet, including, e.g., XRD, NMR, FTIR, Raman, TGA, and DSC. From the reported results and discussion, it is concluded that HBB has potential in the field of chemical hydrogen storage given that both thermolytic and hydrolytic dehydrogenations were analyzed. In solid-state chemical hydrogen storage, it cannot be used in the pristine state (risk of explosion during dehydrogenation) but can be used for the synthesis of derivatives with improved dehydrogenation properties. In liquid-state chemical hydrogen storage, it can be studied for room-temperature dehydrogenation, but this requires the development of an active and selective metal-based catalyst. HBB is a thus a candidate for chemical hydrogen storage.

  12. Development of Regenerable High Capacity Boron Nitrogen Hydrides as Hydrogen Storage Materials

    SciTech Connect

    Damle, A.

    2010-02-03

    The objective of this three-phase project is to develop synthesis and hydrogen extraction processes for nitrogen/boron hydride compounds that will permit exploitation of the high hydrogen content of these materials. The primary compound of interest in this project is ammonia-borane (NH{sub 3}BH{sub 3}), a white solid, stable at ambient conditions, containing 19.6% of its weight as hydrogen. With a low-pressure on-board storage and an efficient heating system to release hydrogen, ammonia-borane has a potential to meet DOE's year 2015 specific energy and energy density targets. If the ammonia-borane synthesis process could use the ammonia-borane decomposition products as the starting raw material, an efficient recycle loop could be set up for converting the decomposition products back into the starting boron-nitrogen hydride. This project is addressing two key challenges facing the exploitation of the boron/nitrogen hydrides (ammonia-borane), as hydrogen storage material: (1) Development of a simple, efficient, and controllable system for extracting most of the available hydrogen, realizing the high hydrogen density on a system weight/volume basis, and (2) Development of a large-capacity, inexpensive, ammonia-borane regeneration process starting from its decomposition products (BNHx) for recycle. During Phase I of the program both catalytic and non-catalytic decomposition of ammonia borane are being investigated to determine optimum decomposition conditions in terms of temperature for decomposition, rate of hydrogen release, purity of hydrogen produced, thermal efficiency of decomposition, and regenerability of the decomposition products. The non-catalytic studies provide a base-line performance to evaluate catalytic decomposition. Utilization of solid phase catalysts mixed with ammonia-borane was explored for its potential to lower the decomposition temperature, to increase the rate of hydrogen release at a given temperature, to lead to decomposition products

  13. Self-assembled air-stable magnesium hydride embedded in 3-D activated carbon for reversible hydrogen storage.

    PubMed

    Shinde, S S; Kim, Dong-Hyung; Yu, Jin-Young; Lee, Jung-Ho

    2017-06-01

    The rational design of stable, inexpensive catalysts with excellent hydrogen dynamics and sorption characteristics under realistic environments for reversible hydrogen storage remains a great challenge. Here, we present a simple and scalable strategy to fabricate a monodispersed, air-stable, magnesium hydride embedded in three-dimensional activated carbon with periodic synchronization of transition metals (MHCH). The high surface area, homogeneous distribution of MgH2 nanoparticles, excellent thermal stability, high energy density, steric confinement by carbon, and robust architecture of the catalyst resulted in a noticeable enhancement of the hydrogen storage performance. The resulting MHCH-5 exhibited outstanding hydrogen storage performance, better than that of most reported Mg-based hydrides, with a high storage density of 6.63 wt% H2, a rapid kinetics loading in <5 min at 180 °C, superior reversibility, and excellent long-term cycling stability over ∼435 h. The significant reduction of the enthalpy and activation energy observed in the MHCH-5 demonstrated enhancement of the kinetics of de-/hydrogenation compared to that of commercial MgH2. The origin of the intrinsic hydrogen thermodynamics was elucidated via solid state (1)H NMR. This work presents a readily scaled-up strategy towards the design of realistic catalysts with superior functionality and stability for applications in reversible hydrogen storage, lithium ion batteries, and fuel cells.

  14. New Pathways and Metrics for Enhanced, Reversible Hydrogen Storage in Boron-Doped Carbon Nanospaces

    SciTech Connect

    Pfeifer, Peter; Wexler, Carlos; Hawthorne, M. Frederick; Lee, Mark W.; Jalistegi, Satish S.

    2014-08-14

    This project, since its start in 2007—entitled “Networks of boron-doped carbon nanopores for low-pressure reversible hydrogen storage” (2007-10) and “New pathways and metrics for enhanced, reversible hydrogen storage in boron-doped carbon nanospaces” (2010-13)—is in support of the DOE's National Hydrogen Storage Project, as part of the DOE Hydrogen and Fuel Cells Program’s comprehensive efforts to enable the widespread commercialization of hydrogen and fuel cell technologies in diverse sectors of the economy. Hydrogen storage is widely recognized as a critical enabling technology for the successful commercialization and market acceptance of hydrogen powered vehicles. Storing sufficient hydrogen on board a wide range of vehicle platforms, at energy densities comparable to gasoline, without compromising passenger or cargo space, remains an outstanding technical challenge. Of the main three thrust areas in 2007—metal hydrides, chemical hydrogen storage, and sorption-based hydrogen storage—sorption-based storage, i.e., storage of molecular hydrogen by adsorption on high-surface-area materials (carbons, metal-organic frameworks, and other porous organic networks), has emerged as the most promising path toward achieving the 2017 DOE storage targets of 0.055 kg H2/kg system (“5.5 wt%”) and 0.040 kg H2/liter system. The objective of the project is to develop high-surface-area carbon materials that are boron-doped by incorporation of boron into the carbon lattice at the outset, i.e., during the synthesis of the material. The rationale for boron-doping is the prediction that boron atoms in carbon will raise the binding energy of hydro- gen from 4-5 kJ/mol on the undoped surface to 10-14 kJ/mol on a doped surface, and accordingly the hydro- gen storage capacity of the material. The mechanism for the increase in binding energy is electron donation from H2 to electron-deficient B atoms, in the form of sp2 boron-carbon bonds. Our team is proud to have

  15. Chemical Hydride Slurry for Hydrogen Production and Storage

    SciTech Connect

    McClaine, Andrew W

    2008-09-30

    The purpose of this project was to investigate and evaluate the attractiveness of using a magnesium chemical hydride slurry as a hydrogen storage, delivery, and production medium for automobiles. To fully evaluate the potential for magnesium hydride slurry to act as a carrier of hydrogen, potential slurry compositions, potential hydrogen release techniques, and the processes (and their costs) that will be used to recycle the byproducts back to a high hydrogen content slurry were evaluated. A 75% MgH2 slurry was demonstrated, which was just short of the 76% goal. This slurry is pumpable and storable for months at a time at room temperature and pressure conditions and it has the consistency of paint. Two techniques were demonstrated for reacting the slurry with water to release hydrogen. The first technique was a continuous mixing process that was tested for several hours at a time and demonstrated operation without external heat addition. Further work will be required to reduce this design to a reliable, robust system. The second technique was a semi-continuous process. It was demonstrated on a 2 kWh scale. This system operated continuously and reliably for hours at a time, including starts and stops. This process could be readily reduced to practice for commercial applications. The processes and costs associated with recycling the byproducts of the water/slurry reaction were also evaluated. This included recovering and recycling the oils of the slurry, reforming the magnesium hydroxide and magnesium oxide byproduct to magnesium metal, hydriding the magnesium metal with hydrogen to form magnesium hydride, and preparing the slurry. We found that the SOM process, under development by Boston University, offers the lowest cost alternative for producing and recycling the slurry. Using the H2A framework, a total cost of production, delivery, and distribution of $4.50/kg of hydrogen delivered or $4.50/gge was determined. Experiments performed at Boston

  16. Improved estimates of separation distances to prevent unacceptable damage to nuclear power plant structures from hydrogen detonation for gaseous hydrogen storage. Technical report

    SciTech Connect

    Not Available

    1994-05-01

    This report provides new estimates of separation distances for nuclear power plant gaseous hydrogen storage facilities. Unacceptable damage to plant structures from hydrogen detonations will be prevented by having hydrogen storage facilities meet separation distance criteria recommended in this report. The revised standoff distances are based on improved calculations on hydrogen gas cloud detonations and structural analysis of reinforced concrete structures. Also, the results presented in this study do not depend upon equivalencing a hydrogen detonation to an equivalent TNT detonation. The static and stagnation pressures, wave velocity, and the shock wave impulse delivered to wall surfaces were computed for several different size hydrogen explosions. Separation distance equations were developed and were used to compute the minimum separation distance for six different wall cases and for seven detonating volumes (from 1.59 to 79.67 lbm of hydrogen). These improved calculation results were compared to previous calculations. The ratio between the separation distance predicted in this report versus that predicted for hydrogen detonation in previous calculations varies from 0 to approximately 4. Thus, the separation distances results from the previous calculations can be either overconservative or unconservative depending upon the set of hydrogen detonation parameters that are used. Consequently, it is concluded that the hydrogen-to-TNT detonation equivalency utilized in previous calculations should no longer be used.

  17. Hydrogen storage in Pd nanocrystals covered with a metal-organic framework

    NASA Astrophysics Data System (ADS)

    Li, Guangqin; Kobayashi, Hirokazu; Taylor, Jared M.; Ikeda, Ryuichi; Kubota, Yoshiki; Kato, Kenichi; Takata, Masaki; Yamamoto, Tomokazu; Toh, Shoichi; Matsumura, Syo; Kitagawa, Hiroshi

    2014-08-01

    Hydrogen is an essential component in many industrial processes. As a result of the recent increase in the development of shale gas, steam reforming of shale gas has received considerable attention as a major source of H2, and the more efficient use of hydrogen is strongly demanded. Palladium is well known as a hydrogen-storage metal and an effective catalyst for reactions related to hydrogen in a variety of industrial processes. Here, we present remarkably enhanced capacity and speed of hydrogen storage in Pd nanocrystals covered with the metal-organic framework (MOF) HKUST-1 (copper(II) 1,3,5-benzenetricarboxylate). The Pd nanocrystals covered with the MOF have twice the storage capacity of the bare Pd nanocrystals. The significantly enhanced hydrogen storage capacity was confirmed by hydrogen pressure-composition isotherms and solid-state deuterium nuclear magnetic resonance measurements. The speed of hydrogen absorption in the Pd nanocrystals is also enhanced by the MOF coating.

  18. Hydrogen storage in Pd nanocrystals covered with a metal-organic framework.

    PubMed

    Li, Guangqin; Kobayashi, Hirokazu; Taylor, Jared M; Ikeda, Ryuichi; Kubota, Yoshiki; Kato, Kenichi; Takata, Masaki; Yamamoto, Tomokazu; Toh, Shoichi; Matsumura, Syo; Kitagawa, Hiroshi

    2014-08-01

    Hydrogen is an essential component in many industrial processes. As a result of the recent increase in the development of shale gas, steam reforming of shale gas has received considerable attention as a major source of H2, and the more efficient use of hydrogen is strongly demanded. Palladium is well known as a hydrogen-storage metal and an effective catalyst for reactions related to hydrogen in a variety of industrial processes. Here, we present remarkably enhanced capacity and speed of hydrogen storage in Pd nanocrystals covered with the metal-organic framework (MOF) HKUST-1 (copper(II) 1,3,5-benzenetricarboxylate). The Pd nanocrystals covered with the MOF have twice the storage capacity of the bare Pd nanocrystals. The significantly enhanced hydrogen storage capacity was confirmed by hydrogen pressure-composition isotherms and solid-state deuterium nuclear magnetic resonance measurements. The speed of hydrogen absorption in the Pd nanocrystals is also enhanced by the MOF coating.

  19. Analysis of Hydrogen and Competing Technologies for Utility-Scale Energy Storage (Presentation)

    SciTech Connect

    Steward, D.

    2010-02-11

    Presentation about the National Renewable Energy Laboratory's analysis of hydrogen energy storage scenarios, including analysis framework, levelized cost comparison of hydrogen and competing technologies, analysis results, and conclusions drawn from the analysis.

  20. Hydrogen storage of Mg1-xMxH2 (M = Ti, V, Fe) studied using first-principles calculations

    NASA Astrophysics Data System (ADS)

    Bhihi, M.; Lakhal, M.; Labrim, H.; Benyoussef, A.; A. El, Kenz; Mounkachi, O.; K. Hlil, E.

    2012-09-01

    In this work, the hydrogen storage properties of the Mg-based hydrides, i.e., Mg1-x Mx H2 (M = Ti, V, Fe, 0 <= x <= 0.1), are studied using the Korringa—Kohn—Rostoker (KKR) calculation with the coherent potential approximation (CPA). In particular, the nature and concentrations of the alloying elements and their effects are studied. Moreover, the material's stability and hydrogen storage thermodynamic properties are discussed. In particular, we find that the stability and the temperature of desorption decrease without significantly affecting the storage capacities.

  1. Predicted energy densitites for nickel-hydrogen and silver-hydrogen cells embodying metallic hydrides for hydrogen storage

    NASA Technical Reports Server (NTRS)

    Easter, R. W.

    1974-01-01

    Simplified design concepts were used to estimate gravimetric and volumetric energy densities for metal hydrogen battery cells for assessing the characteristics of cells containing metal hydrides as compared to gaseous storage cells, and for comparing nickel cathode and silver cathode systems. The silver cathode was found to yield superior energy densities in all cases considered. The inclusion of hydride forming materials yields cells with very high volumetric energy densities that also retain gravimetric energy densities nearly as high as those of gaseous storage cells.

  2. Complex Hydride Compounds with Enhanced Hydrogen Storage Capacity

    SciTech Connect

    Mosher, Daniel A.; Opalka, Susanne M.; Tang, Xia; Laube, Bruce L.; Brown, Ronald J.; Vanderspurt, Thomas H.; Arsenault, Sarah; Wu, Robert; Strickler, Jamie; Anton, Donald L.; Zidan, Ragaiy; Berseth, Polly

    2008-02-18

    The United Technologies Research Center (UTRC), in collaboration with major partners Albemarle Corporation (Albemarle) and the Savannah River National Laboratory (SRNL), conducted research to discover new hydride materials for the storage of hydrogen having on-board reversibility and a target gravimetric capacity of ≥ 7.5 weight percent (wt %). When integrated into a system with a reasonable efficiency of 60% (mass of hydride / total mass), this target material would produce a system gravimetric capacity of ≥ 4.5 wt %, consistent with the DOE 2007 target. The approach established for the project combined first principles modeling (FPM - UTRC) with multiple synthesis methods: Solid State Processing (SSP - UTRC), Solution Based Processing (SBP - Albemarle) and Molten State Processing (MSP - SRNL). In the search for novel compounds, each of these methods has advantages and disadvantages; by combining them, the potential for success was increased. During the project, UTRC refined its FPM framework which includes ground state (0 Kelvin) structural determinations, elevated temperature thermodynamic predictions and thermodynamic / phase diagram calculations. This modeling was used both to precede synthesis in a virtual search for new compounds and after initial synthesis to examine reaction details and options for modifications including co-reactant additions. The SSP synthesis method involved high energy ball milling which was simple, efficient for small batches and has proven effective for other storage material compositions. The SBP method produced very homogeneous chemical reactions, some of which cannot be performed via solid state routes, and would be the preferred approach for large scale production. The MSP technique is similar to the SSP method, but involves higher temperature and hydrogen pressure conditions to achieve greater species mobility. During the initial phases of the project, the focus was on higher order alanate complexes in the phase space

  3. Hydrogen storage material and process using graphite additive with metal-doped complex hydrides

    DOEpatents

    Zidan, Ragaiy; Ritter, James A.; Ebner, Armin D.; Wang, Jun; Holland, Charles E.

    2008-06-10

    A hydrogen storage material having improved hydrogen absorbtion and desorption kinetics is provided by adding graphite to a complex hydride such as a metal-doped alanate, i.e., NaAlH.sub.4. The incorporation of graphite into the complex hydride significantly enhances the rate of hydrogen absorbtion and desorption and lowers the desorption temperature needed to release stored hydrogen.

  4. Hydrogen Storage: Where We Are Now and Where We Need to Go

    NASA Astrophysics Data System (ADS)

    Thomas, George

    2004-03-01

    Efficient hydrogen storage is a key enabling technology for the utilization of hydrogen as a fuel in light duty vehicles. The physical and chemical nature of hydrogen allows a number of alternative approaches to be used for storing hydrogen - as a gas at high pressures and ambient or lower temperatures, as a cryogenic liquid, chemically bound in a solid or liquid material, or adsorbed on the surface of a porous material structure. In the latter two cases, hydrogen-related properties of the host material, such as hydrogen capacity, reversibility, weight and density, thermodynamic and kinetic properties, play a major role in determining the suitability of the materials' use as a storage medium. Recent advances in materials development, as well as in storage technologies, have provided new materials and new storage methods with significantly improved hydrogen capacities over earlier work and have opened up promising new areas of exploration. An overview of hydrogen storage science and technology will be presented which will, first of all, describe the performance requirements imposed by the marketplace on hydrogen storage systems. The current status of performance that has been achieved for the various storage options mentioned above will then be discussed and, finally, some future directions for hydrogen storage research and development will be identified.

  5. Discovery of novel hydrogen storage materials: an atomic scale computational approach.

    PubMed

    Wolverton, C; Siegel, Donald J; Akbarzadeh, A R; Ozoliņš, V

    2008-02-13

    Practical hydrogen storage for mobile applications requires materials that exhibit high hydrogen densities, low decomposition temperatures, and fast kinetics for absorption and desorption. Unfortunately, no reversible materials are currently known that possess all of these attributes. Here we present an overview of our recent efforts aimed at developing a first-principles computational approach to the discovery of novel hydrogen storage materials. Such an approach requires several key capabilities to be effective: (i) accurate prediction of decomposition thermodynamics, (ii) prediction of crystal structures for unknown hydrides, and (iii) prediction of preferred decomposition pathways. We present examples that illustrate each of these three capabilities: (i) prediction of hydriding enthalpies and free energies across a wide range of hydride materials, (ii) prediction of low energy crystal structures for complex hydrides (such as Ca(AlH(4))(2) CaAlH(5), and Li(2)NH), and (iii) predicted decomposition pathways for Li(4)BN(3)H(10) and destabilized systems based on combinations of LiBH(4), Ca(BH(4))(2) and metal hydrides. For the destabilized systems, we propose a set of thermodynamic guidelines to help identify thermodynamically viable reactions. These capabilities have led to the prediction of several novel high density hydrogen storage materials and reactions.

  6. Hydrogen underground storage in siliciclastic reservoirs - intention and topics of the H2STORE project

    NASA Astrophysics Data System (ADS)

    Pudlo, Dieter; Ganzer, Leonhard; Henkel, Steven; Liebscher, Axel; Kühn, Michael; De Lucia, Marco; Panfilov, Michel; Pilz, Peter; Reitenbach, Viktor; Albrecht, Daniel; Würdemann, Hilke; Gaupp, Reinhard

    2013-04-01

    ) migration. To reveal the relevance of these interactions and their impact on petrophysics and fluid mechanics in H2STORE six subprojects are included, which are devoted to various aspects of hydrogen storage in pore space reservoirs. The analytical and (laboratory) experimental studies will be based on rock and fluid samples issued from different reservoir sandstone and cap rock mudstone types originated from different depths all over Germany. Thereby data on sedimentological, geochemical, mineralogical, hydrochemical, petrophysical and microbiological rock composition will be gained. These studies will be completed with conceptual mathematical and numerical modelling of dynamic reservoir processes, including basin/facies burial evolution, mineralogical alteration, hydro-/geochemical reactions and gas mixing processes coupled with population dynamics of methanogenic microorganisms and dynamic displacement instability effects. The estimation of the hydrogen impact on reservoir behaviour of different rock types at depths will enable an evaluation of the feasibility of "Eco-/Green" methane and synthetic natural gas (SNG) generation by hydrogen reaction with CO2. The verification/falsification of specific processes will also enhance predictions on the operational reliability, the ecological tolerance, and the economic efficiency of future energy storing plants. These aspects are main motivations for any industrial investors and the public acceptance of such new technologies within the framework of an overall power supply by renewable energy production.

  7. Hydrogen storage of intrinsic and vanadium-decorated Mg nanostructures

    NASA Astrophysics Data System (ADS)

    He, Yuping; Zhao, Yiping

    2009-11-01

    MgH2 is very attractive for future solid state H-storage applications, due to its lightweight, low cost, and high H-storage capacity of 7.6 wt%. However, its practical application is limited by its high thermodynamic stability and sluggish reaction kinetics, which could be improved by making nanostructures with large surface-to-volume ratios to enhance surface reaction activity and by adding an appropriate catalyst to accelerate H-sorption kinetics. In this work, an oblique angle deposition (OAD) or oblique angle co-deposition (OACD) technique has been used to sculpture Mg nanostructures and incorporate a nanocatalyst. For an intrinsic Mg film and Mg nanoblade array by OAD on Ti coated Si, the hydrogenation results show that the nanoblades start to absorb H2 at 523 Khydrogenation behavior. In addition, by OACD, a 2.25 at% V decorated Mg nanoblade array has been fabricated. It can absorb and desorb H2 rapidly at T > 500 K after activation by one hydrogenation cycling, with low H-absorption activation energy of 35.0 ± 1.2 kJ/mol H2 and desorption activation energy of 65.0 ± 0.3 kJ/mol H2. The improved H-sorption kinetics is attributed to both the catalytic effect of the V coating and the unique nanoblade morphology.

  8. NMR characterization of the hydrogen storage properties of microporous materials

    NASA Astrophysics Data System (ADS)

    Anderson, Robert James

    Nuclear magnetic resonance techniques were employed to study properties and characteristics related to hydrogen storage within a variety of carbon nanomaterials. NMR methods were established for studying adsorption at temperatures of 100 and 290 K, and hydrogen pressures up to 10 MPa. A standard interpretation of the NMR spectra of molecular hydrogen in microporous materials was developed. The characterization of three samples are included here: boron-doped graphite, activated PEEK (a polymer), and zeolite-templated carbon. In all of the studies discussed here, each sample necessitated a custom approach to interpreting the data. The chemical shift, a relaxation filter, and low temperature dynamics were needed to uncover a significantly enhanced binding energy in the boron-doped graphite. The key result of the activated PEEK work was that at 100 K, the pressure-dependent behavior of the chemical shift of the micropore spectral component could be directly linked to the dimensions of the pore. The zeolite-templated carbon displayed local paramagnetic behavior within its pores but was diamagnetic in the bulk form. Pressure-dependent chemical shift analysis revealed that the paramagnetic behavior could be related to the numerous edge sites present.

  9. Progress in improving thermodynamics and kinetics of new hydrogen storage materials

    NASA Astrophysics Data System (ADS)

    Song, Li-fang; Jiang, Chun-hong; Liu, Shu-sheng; Jiao, Cheng-li; Si, Xiao-liang; Wang, Shuang; Li, Fen; Zhang, Jian; Sun, Li-xian; Xu, Fen; Huang, Feng-lei

    2011-06-01

    Hydrogen storage material has been much developed recently because of its potential for proton exchange membrane (PEM) fuel cell applications. A successful solid-state reversible storage material should meet the requirements of high storage capacity, suitable thermodynamic properties, and fast adsorption and desorption kinetics. Complex hydrides, including boron hydride and alanate, ammonia borane, metal organic frameworks (MOFs), covalent organic frameworks (COFs) and zeolitic imidazolate frameworks (ZIFs), are remarkable hydrogen storage materials because of their advantages of high energy density and safety. This feature article focuses mainly on the thermodynamics and kinetics of these hydrogen storage materials in the past few years.

  10. Nickel-hydrogen battery design for the Transporter Energy Storage Subsystem (TESS)

    NASA Technical Reports Server (NTRS)

    Lapinski, John R.; Bourland, Deborah S.

    1992-01-01

    Information is given in viewgraph form on nickel hydrogen battery design for the transporter energy storage subsystem (TESS). Information is given on use in the Space Station Freedom, the launch configuration, use in the Mobile Servicing Center, battery design requirements, TESS subassembley design, proof of principle testing of a 6-cell battery, possible downsizing of TESS to support the Mobile Rocket Servicer Base System (MBS) redesign, TESS output capacity, and cell testing.

  11. Polymers of intrinsic microporosity (PIMs): organic materials for membrane separations, heterogeneous catalysis and hydrogen storage.

    PubMed

    McKeown, Neil B; Budd, Peter M

    2006-08-01

    This tutorial review describes recent research directed towards the synthesis of polymer-based organic microporous materials termed Polymers of Intrinsic Microporosity (PIMs). PIMs can be prepared either as insoluble networks or soluble polymers with both types giving solids that exhibit analogous behaviour to that of conventional microporous materials such as activated carbons. Soluble PIMs may be processed into thin films for use as highly selective gas separation membranes. Preliminary results also demonstrate the potential of PIMs for heterogeneous catalysis and hydrogen storage.

  12. Theoretical study of molecular hydrogen and spiltover hydrogen storage on two-dimensional covalent-organic frameworks

    NASA Astrophysics Data System (ADS)

    Liu, Xiu-Ying; He, Jie; Yu, Jing-Xin; Li, Zheng-Xin; Fan, Zhi-Qin

    2014-06-01

    Molecular hydrogen and spiltover hydrogen storages on five two-dimensional (2D) covalent-organic frameworks (COFs) (PPy-COF, TP-COF, BTP-COF, COF-18 Å, and HHTP-DPB COF) are investigated using the grand canonical Monte Carlo (GCMC) simulations and the density functional theory (DFT), respectively. The GCMC simulated results show that HHTP-DPB COF has the best performance for hydrogen storage, followed by BTP-COF, TP-COF, COF-18 Å, and PPy-COF. However, their adsorption amounts at room temperature are all too low to meet the uptake target set by US Department of Energy (US-DOE) and enable practical applications. The effects of pore size, surface area, and isosteric heat of hydrogen on adsorption amount are considered, which indicate that these three factors are all the important factors for determining the H2 adsorption amount. The chemisorptions of spiltover hydrogen atoms on these five COFs represented by the cluster models are investigated using the DFT method. The saturation cluster models are constructed by considering all possible adsorption sites for these cluster models. The average binding energy of a hydrogen atom and the saturation hydrogen storage density are calculated. The large average binding energy indicates that the spillover process may proceed smoothly and reversibly. The saturation hydrogen storage density is much larger than the physisorption uptake of H2 molecules at 298 K and 100 bar (1 bar = 105 Pa), and is close to or exceeds the 2010 US-DOE target of 6 wt% for hydrogen storage. This suggests that the hydrogen storage capacities of these COFs by spillover may be significantly enhanced. Thus 2D COFs studied in this paper are suitable hydrogen storage media by spillover.

  13. Reversible phase modulation and hydrogen storage in multivalent VO2 epitaxial thin films

    NASA Astrophysics Data System (ADS)

    Yoon, Hyojin; Choi, Minseok; Lim, Tae-Won; Kwon, Hyunah; Ihm, Kyuwook; Kim, Jong Kyu; Choi, Si-Young; Son, Junwoo

    2016-10-01

    Hydrogen, the smallest and the lightest atomic element, is reversibly incorporated into interstitial sites in vanadium dioxide (VO2), a correlated oxide with a 3d1 electronic configuration, and induces electronic phase modulation. It is widely reported that low hydrogen concentrations stabilize the metallic phase, but the understanding of hydrogen in the high doping regime is limited. Here, we demonstrate that as many as two hydrogen atoms can be incorporated into each VO2 unit cell, and that hydrogen is reversibly absorbed into, and released from, VO2 without destroying its lattice framework. This hydrogenation process allows us to elucidate electronic phase modulation of vanadium oxyhydride, demonstrating two-step insulator (VO2)-metal (HxVO2)-insulator (HVO2) phase modulation during inter-integer d-band filling. Our finding suggests the possibility of reversible and dynamic control of topotactic phase modulation in VO2 and opens up the potential application in proton-based Mottronics and novel hydrogen storage.

  14. Method and system for hydrogen evolution and storage

    DOEpatents

    Thorn, David L.; Tumas, William; Hay, P. Jeffrey; Schwarz, Daniel E.; Cameron, Thomas M.

    2012-12-11

    A method and system for storing and evolving hydrogen (H.sub.2) employ chemical compounds that can be hydrogenated to store hydrogen and dehydrogenated to evolve hydrogen. A catalyst lowers the energy required for storing and evolving hydrogen. The method and system can provide hydrogen for devices that consume hydrogen as fuel.

  15. Method and System for Hydrogen Evolution and Storage

    DOEpatents

    Thorn, David L.; Tumas, William; Hay, P. Jeffrey; Schwarz, Daniel E.; Cameron, Thomas M.

    2008-10-21

    A method and system for storing and evolving hydrogen employ chemical compounds that can be hydrogenated to store hydrogen and dehydrogenated to evolve hydrogen. A catalyst lowers the energy required for storing and evolving hydrogen. The method and system can provide hydrogen for devices that consume hydrogen as fuel.

  16. A new Li-Al-N-H system for reversible hydrogen storage.

    PubMed

    Lu, Jun; Fang, Zhigang Zak; Sohn, Hong Yong

    2006-07-27

    Complex metal hydrides are considered as a class of candidate materials for hydrogen storage. Lithium-based complex hydrides including lithium alanates (LiAlH(4) and Li(3)AlH(6)) are among the most promising materials owing to its high hydrogen content. In the present work, we investigated dehydrogenation/rehydrogenation reactions of a combined system of Li(3)AlH(6) and LiNH(2). Thermogravimetric analysis (TGA) of Li(3)AlH(6)/3LiNH(2)/4 wt % TiCl(3)-(1)/(3)AlCl(3) mixtures indicated that a large amount of hydrogen (approximately 7.1 wt %) can be released between 150 degrees C and 300 degrees C under a heating rate of 5 degrees C/min in two dehydrogenation reaction steps. The results also show that the dehydrogenation reaction of the new material system is nearly 100% reversible under 2000 psi pressure hydrogen at 300 degrees C. Further, a short-cycle experiment has demonstrated that the new combined material system of alanates and amides can maintain its hydrogen storage capacity upon cycling of the dehydrogenation/rehydrogenation reactions.

  17. Incorporating magnesium and calcium cations in porous organic frameworks for high-capacity hydrogen storage.

    PubMed

    Wang, Lin; Sun, Yingxin; Sun, Huai

    2011-01-01

    We propose incorporating a bi-functional group consisting of magnesium or calcium cations and a 1,2,4,5-benzenetetroxide anion (C6H2O4(4-)) in porous materials to enhance the hydrogen storage capacity. The C6H2O4M2 bifunctional group is highly stable and polarized, and each group provides 18 (M = Mg) or 22 (M = Ca) binding sites for hydrogen molecules with an average binding energy of ca. 10 kJ mol(-1) per hydrogen molecule based on RIMP2/ TZVPP calculations. Two porous materials (PAF-Mg or PAF-Ca) constructed with the bi-functional groups show remarkable improvement in hydrogen uptakes at normal ambient conditions. At 233 K and 10 MPa, the predicted gravimetric uptakes are 6.8 and 6.4 wt% for PAF-Mg and PAF-Ca respectively. This work reveals that fabricating materials with large numbers of binding sites and relatively low binding energies is a promising approach to achieve high capacity for on-board storage of hydrogen.

  18. Energy Dense, Lighweight, Durable, Systems for Storage and Delivery of Hydrogen

    SciTech Connect

    Jacky Pruez; Samir Shoukry; Gergis William; Thomas Evans; Hermann Alcazar

    2008-12-31

    The work presented in this report summarizes the current state-of-the-art in on-board storage on compressed gaseous hydrogen as well as the development of analysis tools, methods, and theoretical data for devising high performance design configurations for hydrogen storage. The state-of-the-art in the area of compressed hydrogen storage reveals that the current configuration of the hydrogen storage tank is a seamless cylindrical part with two end domes. The tank is composed of an aluminum liner overwrapped with carbon fibers. Such a configuration was proved to sustain internal pressures up to 350 bars (5,000 psi). Finite-element stress analyses were performed on filament-wound hydrogen storage cylindrical tanks under the effect of internal pressure of 700 bars (10,000 psi). Tank deformations, stress fields, and intensities induced at the tank wall were examined. The results indicated that the aluminum liner can not sustain such a high pressure and initiate the tank failure. Thus, hydrogen tanks ought to be built entirely out of composite materials based on carbon fibers or other innovative composite materials. A spherical hydrogen storage tank was suggested within the scope of this project. A stress reduction was achieved by this change of the tank geometry, which allows for increasing the amount of the stored hydrogen and storage energy density. The finite element modeling of both cylindrical and spherical tank design configurations indicate that the formation of stress concentration zones in the vicinity of the valve inlet as well as the presence of high shear stresses in this area. Therefore, it is highly recommended to tailor the tank wall design to be thicker in this region and tapered to the required thickness in the rest of the tank shell. Innovative layout configurations of multiple tanks for enhanced conformability in limited space have been proposed and theoretically modeled using 3D finite element analysis. Optimum tailoring of fiber orientations and lay

  19. Assessment of feasible strategies for seasonal underground hydrogen storage in a saline aquifer

    NASA Astrophysics Data System (ADS)

    Sáinz-García, Alvaro; Abarca, Elena; Rubí, Violeta; Grandia, Fidel

    2017-04-01

    Renewable energies are unsteady, which results in temporary mismatches between demand and supply. The conversion of surplus energy to hydrogen and its storage in geological formations is one option to balance this energy gap. This study evaluates the feasibility of seasonal storage of hydrogen produced from wind power in Castilla-León region (northern Spain). A 3D multiphase numerical model is used to test different extraction well configurations during three annual injection-production cycles in a saline aquifer. Results demonstrate that underground hydrogen storage in saline aquifers can be operated with reasonable recovery ratios. A maximum hydrogen recovery ratio of 78%, which represents a global energy efficiency of 30%, has been estimated. Hydrogen upconing emerges as the major risk on saline aquifer storage. However, shallow extraction wells can minimize its effects. Steeply dipping geological structures are key for an efficient hydrogen storage.

  20. Calculation of hydrogen storage capacity of metal-organic and covalent-organic frameworks by spillover.

    PubMed

    Suri, Mayur; Dornfeld, Matthew; Ganz, Eric

    2009-11-07

    We have used accurate ab initio quantum chemistry calculations together with a simple model to study the hydrogen storage capacity of metal-organic and covalent-organic frameworks by spillover. Recent experiments by Tsao et al. [J. Am. Chem. Soc. 131, 1404 (2009)] {based on an earlier work by Li and Yang [J. Am. Chem. Soc. 128, 8136 (2006)]} have found that IRMOF-8 with bridged Pt catalysts can reversibly store up to 4.7 wt % of hydrogen at room temperature and 100 bar. We have calculated the binding energy for multiple H atoms on model molecules. By counting active storage sites, we predict a saturation excess storage density at room temperature of 5.0 wt % for IRMOF-8. We also predict storage densities of 4.5 wt % for IRMOF-1, 5.4 wt % for MOF-177, 4.5 wt % for COF-1, and 5.7 wt % for IRMOF-15 and IRMOF-16. This suggests that the current experimental H storage results for IRMOF-8 are well optimized. However, for other materials such as MOF-177 and COF-1, the experimental results are not yet optimized, and significantly more H can be stored on these materials. We also find that significant strain will result from shrinkage of the linker molecules as H atoms are loaded onto the crystals.