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Sample records for nanocrystalline dye-sensitized solar

  1. Dye-sensitized solar cells based on nanocrystalline titania electrodes made at various sintering temperatures.

    PubMed

    Stathatos, Elias; Lianos, Panagiotis

    2007-02-01

    Dye-sensitized solar cells were made by using nanocrystalline titania deposited on Fluorine-doped SnO2 (FTO) electrodes. Nanocrystalline titania deposition was made by the sol-gel method using reverse micelles of bis(2-ethylhexyl) sulfosuccinate sodium salt (AOT) in cyclohexane as reaction medium. This surfactant could be easily removed from the deposited nanocomposite organic-inorganic film by simple rinsing with distilled water, without affecting titania adherence on FTO electrode. These nanocrystalline titania electrodes were used to make solar cells either without sintering or after sintering at various temperatures. Sintering extensively affected short circuit current but had small effect on device open-circuit voltage. Thus satisfactory photovoltaic response could be obtained even with devices made of non-sintered (room-temperature) titania. PMID:17450794

  2. Preparation of mesoporous nanocrystalline anatase TiO2 for dye sensitized solar cell application

    NASA Astrophysics Data System (ADS)

    Jacob, K. Stanly; Abraham, P. A.; Panicker, N. Rani; Pramanik, N. C.

    2014-01-01

    Dye sensitized solar cell (DSSC) introduced by Prof.M.Gratzel is a low cost alternative to the existing silicon based solar cells. Solar light conversion efficiency of the current DSSC can be further improved by replacing the conventional anatase TiO2 having lesser surface area with mesoporous high surface area anatase TiO2. This paper describes the sol-gel synthesis of mesoporous high surface area nanocrystalline anatase TiO2 by the controlled hydrolysis and condensation of titanium isopropoxide followed by heat treatment. XRD reveals that xerogel heat treated at 500°C is phase pure anatase. Crystallite size of prepared anatase TiO2 calculated using Scherrer equation was found to be 15 nm. BET analysis of prepared anatase TiO2 exhibited relatively high specific surface area of 97 m2/g, which is found to be almost double to that of the anatase TiO2 generally used for DSSC photo anode fabrication. The pore size distribution (BJH plot) also revealed the mesoporous nature of prepared anatase TiO2 having an average pore size of 7.4 nm.

  3. Photochemical solar cells based on dye-sensitization of nanocrystalline TiO{sub 2}

    SciTech Connect

    Deb, S.K.; Ellingson, R.; Ferrere, S.; Frank, A.J.; Gregg, B.A.; Nozik, A.J.; Park, N.; Schlichthoerl, G.

    1998-09-01

    A photoelectrochemical solar cell that is based on the dye-sensitization of thin nanocrystalline films of TiO{sub 2} (anatase) nanoparticles in contact with a non-aqueous liquid electrolyte is described. The cell, fabricated at NREL, shows a conversion efficiency of {approximately} 9.2% at AM1.5, which approaches the best reported value of 10--11% by Graetzel at EPFL in Lausanne, Switzerland. The femtosecond (fs) pump-probe spectroscopy has been used to time resolve the injection of electrons into the conduction band of nanocrystalline TiO{sub 2} films under ambient conditions following photoexcitation of the adsorbed Ru(II)-complex dye. The measurement indicates an instrument-limited {minus}50 fs upper limit on the electron injection time. The authors also report the sensitization of nanocrystalline TiO{sub 2} by a novel iron-based dye, CIS-[Fe{sup II}(2,2{prime}-bipyridine-4,4,{prime}-dicarboxylic acid){sub 2}(CN){sub 2}], a chromophore with an extremely short-lived, nonemissive excited state. The dye also exhibits a unique band selective sensitization through one of its two absorption bands. The operational principle of the device has been studied through the measurement of electric field distribution within the device structure and studies on the pH dependence of dye-redox potential. The incorporation of WO{sub 3}-based electrochromic layer into this device has led to a novel photoelectrochromic device structure for smart window application.

  4. Dye Sensitized Solar Cells

    PubMed Central

    Wei, Di

    2010-01-01

    Dye sensitized solar cell (DSSC) is the only solar cell that can offer both the flexibility and transparency. Its efficiency is comparable to amorphous silicon solar cells but with a much lower cost. This review not only covers the fundamentals of DSSC but also the related cutting-edge research and its development for industrial applications. Most recent research topics on DSSC, for example, applications of nanostructured TiO2, ZnO electrodes, ionic liquid electrolytes, carbon nanotubes, graphene and solid state DSSC have all been included and discussed. PMID:20480003

  5. Dye sensitized solar cells.

    PubMed

    Wei, Di

    2010-01-01

    Dye sensitized solar cell (DSSC) is the only solar cell that can offer both the flexibility and transparency. Its efficiency is comparable to amorphous silicon solar cells but with a much lower cost. This review not only covers the fundamentals of DSSC but also the related cutting-edge research and its development for industrial applications. Most recent research topics on DSSC, for example, applications of nanostructured TiO(2), ZnO electrodes, ionic liquid electrolytes, carbon nanotubes, graphene and solid state DSSC have all been included and discussed. PMID:20480003

  6. Exciton annihilation in dye-sensitized nanocrystalline semiconductor films

    NASA Astrophysics Data System (ADS)

    Namekawa, Akihiro; Katoh, Ryuzi

    2016-08-01

    Exciton annihilation in dye-sensitized nanocrystalline semiconductor (Al2O3) films has been studied through laser-induced fluorescence spectroscopy. The relative quantum yield of the fluorescence decreases with increasing excitation light intensity, the indication being that exciton annihilation occurred. The rate constants of the annihilation were estimated for three dyes, N719, D149, and MK2, that are known to be sensitizing dyes for efficient dye-sensitized solar cells. The hopping time between dye molecules and the diffusion length of excitons within their lifetime were also estimated to facilitate discussion of the relevance of exciton annihilation to primary processes in dye-sensitized solar cells.

  7. Microwave-assisted synthesis of nanocrystalline TiO2 for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Kuo, Ta-Chuan; Guo, Tzung-Fang; Chen, Peter

    2012-09-01

    The main purposes of this study are replacing conventional hydro-thermal method by microwave heating using water as reaction medium to rapidly synthesize TiO2.Titanium tetraisopropoxide (TTIP) was hydrolyzed in water. The solution is subsequently processed with microwave heating for crystal growth. The reaction time could be shortened into few minutes. Then we chose different acids as dispersion agents to prepare TiO2 paste for investigating the effects of dispersion on the power conversion efficiency of dye-sensitized solar cells (DSCs). The photovoltaic performance of the microwave-assisted synthesized TiO2 achieved power conversion efficiency of 6.31% under AM 1.5 G condition (100 mW/cm2). This PCE value is compatible with that of the devices made from commercial TiO2.

  8. Artificial photosynthesis based on ruthenium(II) tetrazole-dye-sensitized nanocrystalline TiO2 solar cells.

    PubMed

    Shahroosvand, Hashem; Najafi, Leyla; Khanmirzaei, Leyla; Tarighi, Sara

    2015-11-01

    We have demonstrated the optical and morphological properties of a novel TiO2 nanoparticle as photoanode in order to apply in dye sensitized solar cells. The nanoparticles were synthesized through hydrothermal method in Tri-n-octyl amine (TOA) as capping agent. From the results it is concluded that the molar ratio of TiCl4 and TOA has remarkable influence on the size and homogeneity of the nanoparticles. The optimized nanoparticles structure for photoanode incorporated into dye-sensitized solar cell was obtained via the molar ratio of 1:10 for TiCl4:TOA. It has also studied the photovoltaic properties of different synthesized TiO2 nanocrystalline (1-4) anchored to ruthenium(II) complexes. 4-(1H-tetrazole-5-yl) benzoic acid (TzBA) applied as an anchoring ligand and 2,2-bipyridine (bpy), 1,10-phenanthroline (phen) and pyridine tetrazole (pyTz) used as ancillary ligands. A solar energy to electricity conversion efficiency (η) of 1.06% was obtained for [Ru(TzBA)(bpy)(pyTz)(NCS)] (5) under the standard AM 1.5 irradiation with a Jsc of 2.29 mA cm(-2), a Voc of 0.51 V, and FF of 55% which are the highest values among Ru(TzBA) complexes. DSSC study reveals that pyTz as an auxiliary ligand exhibits improved current generating capacity than the bpy and phen, which are introduced by dye (5). PMID:26028126

  9. Characterization of screen-printed dye-sensitized nanocrystalline TiO2 solar cells

    NASA Astrophysics Data System (ADS)

    Gupta, Tapan K.; Cirignano, Leonard J.; Shah, Kanai S.; Moy, Larry P.; Kelly, David J.; Squillante, Michael R.; Entine, Gerald; Smestad, Greg P.

    1999-10-01

    Titanium dioxide (TiO2) films have been deposited on SnO2 coated glass substrates by screen-printing. Film morphology and structure have been characterized by scanning electron microscopy, x-ray diffraction and BET analysis. Dye-sensitized TiO2 photoelectrochemical cells have been assembled and characterized. Cells sensitized with anthocyanin and a ruthenium complex have been investigated. A 0.77 cm2 ruthenium dye sensitized cell with 6.1% power conversion efficiency under Air Mass (AM1.5) conditions was obtained. Results obtained with a pure anthocyanin dye and dye extracted from blackberries were compared. Finally, a natural gel was found to improve the stability of anthocyanin sensitized cells.

  10. Multifunctional alumina/titania hybrid blocking layer modified nanocrystalline titania films as efficient photoanodes in dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Wang, Changlei; Yu, Zhenhua; Bu, Chenghao; Liu, Pei; Bai, Sihang; Liu, Chang; Kondamareddy, Kiran Kumar; Sun, Weiwei; Zhan, Kan; Zhang, Kun; Guo, Shishang; Zhao, Xingzhong

    2015-05-01

    A facile way of fabricating efficient blocking layer on mesoporous TiO2 film of dye-sensitized solar cells (DSSCs) is demonstrated here for the first time. Al2O3 and TiO2 are combined together to form a blocking layer. A simple spin coating technique is employed which is a versatile and low-cost method over the atomic layer deposition (ALD) technique. Multifunctional alumina/titania (Al2O3/TiO2) hybrid overlayer is prepared on traditional TiO2 nanocrystalline thin film surface, through sequential deposition of AlCl3·6H2O and TiCl4 precursor solutions followed by sintering at 500 °C for 30 min. Al2O3 effectively plays its role in retarding interfacial recombination of electrons and improving open circuit potential (Voc), while the tiny TiO2 clusters synthesized from TiCl4 treatment act as electron transporting channels to facilitate electron diffusion which leads to enhanced photocurrent (Jsc). Compared to the device without blocking layer, the DSSCs assembled with Al2O3/TiO2 hybrid blocking layer showed improvement in Jsc (from 13.09 mA/cm2 to 16.90 mA/cm2) as well as in Voc (from 0.72 V to 0.73 V) resulting a much better conversion efficiency of 8.60%.

  11. Home-made experiment of Dye-sensitized TiO2 Nanocrystalline Solar Cells and its education evaluation

    NASA Astrophysics Data System (ADS)

    Tai, M. F.; Shieh, M. C.; Chen, T. W.

    2010-03-01

    Dyes extracted from some natural fruits including anthocyanins absorb sunlight and effectively activate electrons of anthocyanins. Thus these activated electrons are conducted between TiO2 nanocrystals and form electric potential and current between two electrodes. The dyes can be gotten from the natural fruits, such as blackberries, raspberry, pomegranate seeds and bing cherries. This principle permits making a dye sensitized TiO2 nanocrystallines solar cell (DSSC). All required materials and tools for fabricating a home- made DSSC are easy to obtain around home. The procedures are perfect hands-on experiment as well as demonstration in K-12 schools or home settings. We have designed several protocols for fabricating DSSC and have successfully demonstrated in more than 100 activities with different level students. K-12 Students were able to build their own working DSSC's within 2-3 hours sessions and learned about alternative energy sources. These experiments can inspire students and general public about the modern technology in daily life. Low cost (low than US 3 in Taiwan)and safety are also ensured in our DSSC experiments.

  12. Cation control of energetics on dye-sensitized nanocrystalline TiO2 for solar cells

    NASA Astrophysics Data System (ADS)

    Stux, Arnold M.

    Regenerative solar cells based on nanocrystalline TiO2 (anatase) and the dye Ru(deeb)(bpy)2(PF6)2, where deeb is 4,4'-(CO2CH2CH3)2-2,2 '-bipyridine and bpy is 2,2'-bipyridine, have increased efficiency when in the presence of a high concentration of cations with a large charge-to-radius ratio. Concentration-dependent photoluminescence (PL) quenching and increased quantum yield for interfacial charge separation have been explored for mono- and divalent cations by absorbance, time-resolved and steady-state PL. Cation adsorption stabilizes TiO2 acceptor states resulting in energetically favorable electron transfer from the dye into the semiconductor conduction band. Quenching of the PL of excited states is reversible. A new luminescence approach for sensing alkali and alkaline earth metal cations utilizes the surface-adsorption/desorption induced energetic shifts of a semiconductor conduction band to alter the electron transfer quenching efficiency of a photoluminescent dye such as Ru(deeb)(bpy)2(PF 6)2 anchored to TiO2 nanoparticles. This approach yields intensity, lifetime, and wavelength-ratiometric calcium ion sensors that are sensitive to 5 x 10-4 M concentrations. In situ photoluminescence of a regenerative solar cell has been demonstrated as a probe of injection and efficiencies. The smaller the alkali cation, the higher the photocurrent and the more quenched the photoluminescence. The extent of quenching in 0.1 M iodide/0.01 M iodine electrolytes was 10-fold with LiI and 3-fold with NaI. A millimolar threshold concentration is observed for Li+ at which point a red shift in absorbance and photoluminescence spectra concomitant with significant static and dynamic quenching occurs. For Na+, the threshold concentration for observable red shift is more than an order of magnitude higher than for Li+. Cation adsorption was also observed on planar TiO2 surfaces in the absence of dye. The flat band potentials of single crystal TiO 2 (rutile) with cations in propylene

  13. Clean and time-effective synthesis of anatase TiO2 nanocrystalline by microwave-assisted solvothermal method for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Shen, Po-Shen; Tai, Yu-Chuen; Chen, Peter; Wu, Yu-Chun

    2014-02-01

    In this article, we report a clean and time-effective solvothermal synthesis route using microwave-assisted heating method to prepare nanocrystalline anatase TiO2 with its application for dye-sensitized solar cells. With this proposed method, pure anatase TiO2 nanoparticles with size about 20 nm are successfully obtained at 220 °C for 30 min. Our method of microwave-assisted organic solvothermal route significantly reduces the elaborating process of washing and solvent exchange for the subsequent paste formation. The as-synthesized TiO2 colloidal solution is ready for particle dispersion that markedly simplified the preparation procedures. Material characterizations of the anatase TiO2 nanoparticles are performed by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS), respectively. The photovoltaic performances of the dye-sensitized solar cells assembled with the as-synthesized TiO2 nanocrystallines as photoanodes in various film thicknesses are examined. An excellent energy conversion efficiency of 7.8% is achieved which is comparable to the previously reported dye-sensitized solar cells made of hydrothermal microwave-synthesized TiO2.

  14. Dye-sensitized solar cells

    DOEpatents

    Skotheim, T.A.

    1980-03-04

    A low-cost dye-sensitized Schottky barrier solar cell is comprised of a substrate of semiconductor with an ohmic contact on one face, a sensitizing dye adsorbed onto the opposite face of the semiconductor, a transparent thin-film layer of a reducing agent over the dye, and a thin-film layer of metal over the reducing agent. The ohmic contact and metal layer constitute electrodes for connection to an external circuit and one or the other or both are made transparent to permit light to penetrate to the dye and be absorbed therein for generating electric current. The semiconductor material chosen to be the substrate is one having a wide bandgap and which therefore is transparent; the dye selected is one having a ground state within the bandgap of the semiconductor to generate carriers in the semiconductor, and a first excited state above the conduction band edge of the semiconductor to readily conduct electrons from the dye to the semiconductor; the reducing agent selected is one having a ground state above the ground state of the sensitizer to provide a plentiful source of electrons to the dye during current generation and thereby enhance the generation; and the metal for the thin-film layer of metal is selected to have a Fermi level in the vicinity of or above the ground state of the reducing agent to thereby amply supply electrons to the reducing agent. 3 figs.

  15. Dye-sensitized solar cells

    DOEpatents

    Skotheim, Terje A. [Berkeley, CA

    1980-03-04

    A low-cost dye-sensitized Schottky barrier solar cell comprised of a substrate of semiconductor with an ohmic contact on one face, a sensitizing dye adsorbed onto the opposite face of the semiconductor, a transparent thin-film layer of a reducing agent over the dye, and a thin-film layer of metal over the reducing agent. The ohmic contact and metal layer constitute electrodes for connection to an external circuit and one or the other or both are made transparent to permit light to penetrate to the dye and be absorbed therein for generating electric current. The semiconductor material chosen to be the substrate is one having a wide bandgap and which therefore is transparent; the dye selected is one having a ground state within the bandgap of the semiconductor to generate carriers in the semiconductor, and a first excited state above the conduction band edge of the semiconductor to readily conduct electrons from the dye to the semiconductor; the reducing agent selected is one having a ground state above the ground state of the sensitizer to provide a plentiful source of electrons to the dye during current generation and thereby enhance the generation; and the metal for the thin-film layer of metal is selected to have a Fermi level in the vicinity of or above the ground state of the reducing agent to thereby amply supply electrons to the reducing agent.

  16. Enhanced photovoltaic performance of dye-sensitized solar cells based on NaYF4:Yb(3+), Er(3+)-incorporated nanocrystalline TiO2 electrodes.

    PubMed

    Zhu, Guang; Wang, Hongyan; Zhang, Quanxin; Zhang, Li

    2015-08-01

    Near infrared to visible up-conversion of light by rare earth ion-doped phosphors (NaYF4:Yb(3+), Er(3+)) that convert multiple photons of lower energy to higher energy photons offer new possibilities for improved performance of photovoltaic devices. Here, up-conversion phosphor NaYF4:Yb(3+), Er(3+) doped nanocrystalline TiO2 films are designed and used as a electrode for dye-sensitized solar cells, and the photovoltaic performance of DSSCs based on composite electrodes are investigated. The results show the cell with NaYF4:Yb(3+), Er(3+) achieves a power conversion efficiency of 7.65% under one sun illumination (AM 1.5G, 100mWcm(-2)), which is an increase of 14% compared to the cell without NaYF4:Yb(3+), Er(3+) (6.71%). The performance improvement is attributed to the dual effects of enhanced light harvesting from extended light absorption range and increased light scattering, and lower electron transfer resistance. PMID:25875488

  17. Stretchable, wearable dye-sensitized solar cells.

    PubMed

    Yang, Zhibin; Deng, Jue; Sun, Xuemei; Li, Houpu; Peng, Huisheng

    2014-05-01

    A stretchable, wearable dye-sensitized solar-cell textile is developed from elastic, electrically conducting fiber as a counter electrode and spring-like titanium wire as the working electrode. Dyesensitized solar cells are demonstrated with energy-conversion efficiencies up to 7.13%. The high energy-conversion efficiencies can be well maintained under stretch by 30% and after stretch for 20 cycles. PMID:24648169

  18. Dye-sensitization of nanocrystalline semiconductor electrodes

    NASA Astrophysics Data System (ADS)

    Stipkala, Jeremy M.

    Electron transfer from excited sensitizer molecules into colloidal titanium dioxide thin film electrodes in the absence of an intimate covalent bond has been exploited to convert light into electricity. A brief review of research reported in the literature is given, which focuses on the kinetics of interfacial charge transfer events at sensitized sol-gel processed semiconductor particles. It was found that forward electron transfer from the sensitizer to the semiconductor is several orders of magnitude faster than the energy wasting recombination in the most successful systems. The novel results included here detail two new approaches to the problem of immobilizing sensitizers on the surface of the semiconductor. First, linkage ligands 4-methyl-4sp'-R-2,2sp'-bipyridine, where R = -COOH, -(CHsb2)sb3COOH, and -(CHsb2)sb3COCHsb2COOCsb2Hsb5 were synthesized. These ligands were incorporated into the sensitizer RuspII(dmb)sb2LL(PFsb6)sb2, where dmb = 4,4sp'-dimethyl-2,2sp'-bipyridine, and LL is the linkage ligand. The performance of these ruthenium sensitizers in regenerative solar cells was measured. It was found that the presence of the propylene spacer slows the recombination of the injected electron in the semiconductor with the oxidized sensitizer by a factor of 3-4. Second, electropolymerization of RuspII(vbpy) compounds, where vbpy is 4-methyl-4sp'-vinyl-2,2sp'-bipyridine, is explained. If the polymerization conditions are kept within narrow parameters, it is possible to add polymeric sensitizer to the semiconductor electrode and improve the cell performance. It was often observed, however, that the addition of polymer increased the dye surface coverage but lowered light-to-electricity conversion efficiencies. Evidence for self-quenching and iodide diffusion inhibition as mechanistic explanations for the reduced efficiencies from polymeric samples is given.

  19. Scanning photo-electrochemical microscopy as a versatile tool to investigate dye-sensitized nano-crystalline surfaces for solar cells

    NASA Astrophysics Data System (ADS)

    Figgemeier, Egbert; Kylberg, William H.; Bozic, Biljana

    2006-04-01

    Self-assembled monolayers (SAMs) of metal complexes are a central component of functional chemical systems for energy conversion like in e.g. the dye-sensitized photoelectrochemical solar cells or photocatalytic processes at semiconductor surfaces. In this context, scanning electrochemical microscopy (SECM) under illumination is a most valuable tool for the understanding of elementary processes of such systems. SECM comprises an ultra-microelectrode (UME), which is incorporated into a 3- or 4-electrode, respectively, electrochemical setup and which can be positioned with sub-micrometer resolution in 3 dimensions relative to a substrate. In our system, we used Pt-UMEs and dye-sensitized nano-structured electrodes as substrates. The substrate can be illuminated from the backside, which resembles working conditions of solar cell arrangements. The electrolyte consists of 2-methoxypropionitrile in conjunction with redox couples as they are used in dye-sensitized nano-structured solar cell. With this setup the photoelectrochemistry in close contact to the substrate surface initiated by the injection of electrons from the dye into the conduction band of the TiO II due to illumination at working conditions has been investigated. In this contribution we present the general principle of the method as well as an initial validation by relating photocurrents measured with the SECM and solar cell performances.

  20. Dye-sensitized solar cells using laser processing techniques

    NASA Astrophysics Data System (ADS)

    Kim, Heungsoo; Pique, Alberto; Kushto, Gary P.; Auyeung, Raymond C. Y.; Lee, S. H.; Arnold, Craig B.; Kafafi, Zakia H.

    2004-07-01

    Laser processing techniques, such as laser direct-write (LDW) and laser sintering, have been used to deposit mesoporous nanocrystalline TiO2 (nc-TiO2) films for use in dye-sensitized solar cells. LDW enables the fabrication of conformal structures containing metals, ceramics, polymers and composites on rigid and flexible substrates without the use of masks or additional patterning techniques. The transferred material maintains a porous, high surface area structure that is ideally suited for dye-sensitized solar cells. In this experiment, a pulsed UV laser (355nm) is used to forward transfer a paste of commercial TiO2 nanopowder (P25) onto transparent conducting electrodes on flexible polyethyleneterephthalate (PET) and rigid glass substrates. For the cells based on flexible PET substrates, the transferred TiO2 layers were sintered using an in-situ laser to improve electron paths without damaging PET substrates. In this paper, we demonstrate the use of laser processing techniques to produce nc-TiO2 films (~10 μm thickness) on glass for use in dye-sensitized solar cells (Voc = 690 mV, Jsc = 8.7 mA/cm2, ff = 0.67, η = 4.0 % at 100 mW/cm2). This work was supported by the Office of Naval Research.

  1. EH AND S ANALYSIS OF DYE-SENSITIZED PHOTOVOLTAIC SOLAR CELL PRODUCTION.

    SciTech Connect

    BOWERMAN,B.; FTHENAKIS,V.

    2001-10-01

    Photovoltaic solar cells based on a dye-sensitized nanocrystalline titanium dioxide photoelectrode have been researched and reported since the early 1990's. Commercial production of dye-sensitized photovoltaic solar cells has recently been reported in Australia. In this report, current manufacturing methods are described, and estimates are made of annual chemical use and emissions during production. Environmental, health and safety considerations for handling these materials are discussed. This preliminary EH and S evaluation of dye-sensitized titanium dioxide solar cells indicates that some precautions will be necessary to mitigate hazards that could result in worker exposure. Additional information required for a more complete assessment is identified.

  2. Nanowire dye-sensitized solar cells.

    PubMed

    Law, Matt; Greene, Lori E; Johnson, Justin C; Saykally, Richard; Yang, Peidong

    2005-06-01

    Excitonic solar cells-including organic, hybrid organic-inorganic and dye-sensitized cells (DSCs)-are promising devices for inexpensive, large-scale solar energy conversion. The DSC is currently the most efficient and stable excitonic photocell. Central to this device is a thick nanoparticle film that provides a large surface area for the adsorption of light-harvesting molecules. However, nanoparticle DSCs rely on trap-limited diffusion for electron transport, a slow mechanism that can limit device efficiency, especially at longer wavelengths. Here we introduce a version of the dye-sensitized cell in which the traditional nanoparticle film is replaced by a dense array of oriented, crystalline ZnO nanowires. The nanowire anode is synthesized by mild aqueous chemistry and features a surface area up to one-fifth as large as a nanoparticle cell. The direct electrical pathways provided by the nanowires ensure the rapid collection of carriers generated throughout the device, and a full Sun efficiency of 1.5% is demonstrated, limited primarily by the surface area of the nanowire array. PMID:15895100

  3. nanostructures for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Rashad, M. M.; Shalan, A. E.

    2014-08-01

    Hierarchical architectures consisting of one-dimensional (1D) nanostructures are of great interest for potential use in energy and environmental applications in recent years. In this work, hierarchical tungsten oxide (WO3) has been synthesized via a facile hydrothermal route from ammonium metatungstate hydrate and implemented as photoelectrode for dye-sensitized solar cells. The urchin-like WO3 micro-patterns are constructed by self-organized nanoscale length 1D building blocks, which are single crystalline in nature, grown along (001) direction and confirm an orthorhombic crystal phase. The obtained powders were investigated by XRD, SEM, TEM and UV-Vis Spectroscopy. The photovoltaic performance of dye-sensitized solar cells based on WO3 photoanodes was investigated. With increasing the calcination temperature of the prepared nanopowders, the light-electricity conversion efficiency ( η) was increased. The results were attributed to increase the crystallinity of the particles and ease of electron movement. The DSSC based on hierarchical WO3 showed a short-circuit current, an open-circuit voltage, a fill factor, and a conversion efficiency of 4.241 mA/cm2, 0.656 V, 66.74, and 1.85 %, respectively.

  4. Improving the dye-sensitized solar cell

    NASA Astrophysics Data System (ADS)

    Willig, Frank

    2007-09-01

    Two dye sensitized solar cells (DSC) can be joined to form a tandem cell with two separate absorption ranges for the two different absorber materials. This can enhance the solar conversion efficiency and in particular the photovoltage of the DSC. Water splitting appears as a realistic long term target. The DSC tandem can be realized as n-n junction employing known dye molecules with optimal absorption spectra. Dye molecules with elongated shapes can be realized by covalently attaching a conducting bridge group terminated by an anchor group to a desired chromophore. Due to the long conducting bridge group separating the hole state of the dye from the surface of the semiconductor recombination is slowed down. The ordered molecular structure can be self-assembled on the recently introduced rod or cylinder shaped oxide electrodes but will not slow down recombination in the nm-cavities of the conventional TiO II Graetzel electrode.

  5. Nano-crystalline thin and nano-particulate thick TiO{sub 2} layer: Cost effective sequential deposition and study on dye sensitized solar cell characteristics

    SciTech Connect

    Das, P.; Sengupta, D.; Kasinadhuni, U.; Mondal, B.; Mukherjee, K.

    2015-06-15

    Highlights: • Thin TiO{sub 2} layer is deposited on conducting substrate using sol–gel based dip coating. • TiO{sub 2} nano-particles are synthesized using hydrothermal route. • Thick TiO{sub 2} particulate layer is deposited on prepared thin layer. • Dye sensitized solar cells are made using thin and thick layer based photo-anode. • Introduction of thin layer in particulate photo-anode improves the cell efficiency. - Abstract: A compact thin TiO{sub 2} passivation layer is introduced between the mesoporous TiO{sub 2} nano-particulate layer and the conducting glass substrate to prepare photo-anode for dye-sensitized solar cell (DSSC). In order to understand the effect of passivation layer, other two DSSCs are also developed separately using TiO{sub 2} nano-particulate and compact thin film based photo-anodes. Nano-particles are prepared using hydrothermal synthesis route and the compact passivation layer is prepared by simply dip coating the precursor sol prepared through wet chemical route. The TiO{sub 2} compact layer and the nano-particles are characterised in terms of their micro-structural features and phase formation behavior. It is found that introduction of a compact TiO{sub 2} layer in between the mesoporous TiO{sub 2} nano-particulate layer and the conducting substrate improves the solar to electric conversion efficiency of the fabricated cell. The dense thin passivation layer is supposed to enhance the photo-excited electron transfer and prevent the recombination of photo-excited electrons.

  6. Dye-Sensitized Solar Cells for Space Power

    NASA Technical Reports Server (NTRS)

    Harris, Jerry D.; Hehemann, David G.; Duraj, Stan A.

    2003-01-01

    During the course of this grant, dye-sensitized solar cells were prepared and characterized. The solar cells were prepared using materials (dyes, electrolytes, transparent conductive oxide coated glass, nanocrystalline TiO2) entirely prepared in-house, as well as prepared using materials available commercially. Complete cells were characterized under simulated AM0 illumination. The best cell prepared at NASA had an AM0 efficiency of 1.22% for a 1.1 sq cm cell. Short circuit current (Isc), open circuit voltage (Voc) and fill factor (FF) for the cell were 6.95 mA, 618 mV and 42.8%, respectively. For comparison purposes, two commercially prepared dye-sensitized solar cells were obtained from Solaronix SA, Aubonne, Switzerland. The Solaronix cells were also characterized under simulated AM0 illumination. The best cell from Solaronix had an active area of 3.71 sq cm and measured an AM0 efficiency of 3.16%. with Isc, Voc and FF of 45.80 mA, 669.6 mV and 52.3%, respectively. Both cells from Solaronix were rapid thermal cycled between -80 C and 80 C. Thermal cycling led to a 4.6% loss of efficiency in one of the cells and led to nearly a complete failure in the second cell.

  7. One-Pot Low Temperature Synthesis and Characterization Studies of Nanocrystalline α-Fe2O3 Based Dye Sensitized Solar Cells.

    PubMed

    Manikandan, A; Saravanan, A; Antony, S Arul; Bououdina, M

    2015-06-01

    Dye-sensitized solar cell (DSSC) based α-Fe2O3 nanostructures with two different morphologies, such as nanorods (FeONRs) and nanoparticles (FeONPs), were synthesized by one-pot low temperature method. The crystal structure and phase purity of the as-prepared samples were characterized by X-ray powder diffraction (XRD) and further determined by Rietveld refinements XRD analysis. The average crystallite size was calculated using Debye Sherrer formula, and it shows the range of 9.43-26.56 nm. The morphologies of the products were studied by high resolution scanning electron microscopy (HR-SEM) and it was confirmed by high resolution transmission electron microscopy (HR-TEM). The formation of pure α-Fe2O3 samples was further confirmed by energy dispersive X-ray (EDX) analysis. The optical properties and the band gap energy (E(g)) were measured by UV-Visible diffuse reflectance spectra (DRS) and photoluminescence (PL) spectra. The band gap energy was measured using Kubelka-Munk method, and the values are decreased from 2.36 eV to 2.21 eV as the temperature increased from 300 to 400 degrees C with increasing the crystallite size. Magnetic hysteresis (M-H) loop revealed that the as-prepared α-Fe2O3 samples displayed ferromagnetic behavior. FeONRs sample shows higher saturation magnetization (M(s)) value (40.21 emu/g) than FeONPs sample (23.06 emu/g). The dye-sensitized solar cell based on the optimized FeONRs array reaches a conversion efficiency of 0.43%, which is higher than that obtained from FeONPs (0.29%) under the light radiation of 1000 W/m2. PMID:26369049

  8. Surface modification of porous nanocrystalline TiO{sub 2} films for dye-sensitized solar cell application by various gas plasmas

    SciTech Connect

    Kim, Youngsoo; Yoon, Chang-Ho; Kim, Kang-Jin; Lee, Yeonhee

    2007-07-15

    Titanium dioxide (TiO{sub 2}) film for dye-sensitized solar cells (DSSCs) has surface defects such as oxygen vacancies created during the annealing process. The authors used a plasma treatment technique to reduce defects on TiO{sub 2} surfaces. They investigated the influence of different gas plasma treatments of TiO{sub 2} film on the photoelectric performance of DSSC. Short-circuit photocurrent density (J{sub sc}), open-circuit photovoltage (V{sub oc}), and the amount of adsorbed dye for DSSCs were measured. As a result, the solar-to-electricity conversion efficiencies of the O{sub 2}- and N{sub 2}-treated cells increased by 15%-20% compared to untreated cells. On the other hand, solar energy conversion efficiency of CF{sub 4}-plasma treated cells decreased drastically. The increased amount of adsorbed dye on the TiO{sub 2} film was measured by time-of-flight secondary ion mass spectrometry. TiO{sub 2} surfaces modified by plasma treatment were characterized using analytical instruments such as x-ray photoelectron spectroscopy and near-edge x-ray absorption fine structure.

  9. Space Environmental Testing of Dye-Sensitized Solar Cells

    NASA Technical Reports Server (NTRS)

    Harris, Jerry D.; Anglin, Emily J.; Hepp, Aloysius F.; Bailey, Sheila G.; Scheiman, David A.; Castro, Stephenie L.; Lyons, Valerie (Technical Monitor)

    2002-01-01

    Recent advances in nanocrystalline dye-sensitized solar cells has lead NASA to investigate the potential of these devices for space power generation, Reported here is the first space environment characterization of these type of photovoltaic devices. Cells containing liquid electrolytes were exposed to simulated low-earth orbit conditions and their performance evaluated. All cells were characterized under simulated air mass zero (AMO) illumination. Complete cells were exposed to pressures less than 1 x 10(exp -7) torr for over a month, with no sign of sealant failure or electrolyte leakage. Cells from Solaronix SA were rapid thermal cycled under simulated low-earth orbit conditions. The cells were cycled 100 times from -80 C to 80 C, which is equivalent to 6 days in orbit. The best cell had a 4.6% loss in efficiency as a result of the thermal cycling,

  10. Nature of photovoltaic action in dye-sensitized solar cells

    SciTech Connect

    Cahen, D.; Hodes, G.; Graetzel, M.; Guillemoles, J.F.; Riess, I.

    2000-03-09

    The authors explain the cause for the photocurrent and photovoltage in nanocrystalline, mesoporous dye-sensitized solar cells, in terms of the separation, recombination, and transport of electronic charge as well as in terms of electron energetics. On the basis of available experimental data, the basic cause for the photovoltage was confirmed as the change in the electron concentration in the nanocrystalline electron conductor that results from photoinduced charge injection from the dye. The maximum photovoltage is given by the difference in electron energies between the redox level and the bottom of the electron conductor's conduction band, rather than by any difference in electrical potential in the cell, in the dark. Charge separation occurs because of the energetic and entropic driving forces that exist at the dye/electron conductor interface, with charge transport aided by such driving forces at the electron conductor-contact interface. The mesoporosity and nanocrystallinity of the semiconductor are important not only because of the large amount of dye that can be adsorbed on the system's very large surface, but also for two additional reasons: (1) it allows the semiconductor small particles to become almost totally depleted upon immersion in the electrolyte (allowing for large photovoltages), and (2) the proximity of the electrolyte to all particles modes screening of injected electrons, and thus their transport, possible.

  11. Dye-sensitized Schottky barrier solar cells

    DOEpatents

    Skotheim, Terje A.

    1978-01-01

    A low-cost dye-sensitized Schottky barrier solar cell comprised of a substrate of semiconductor with an ohmic contact on one face, a sensitizing dye adsorbed onto the opposite face of the semiconductor, a transparent thin-film layer of a reducing agent over the dye, and a thin-film layer of metal over the reducing agent. The ohmic contact and metal layer constitute electrodes for connection to an external circuit and one or the other or both are made transparent to permit light to penetrate to the dye and be absorbed therein for generating electric current. The semiconductor material chosen to be the substrate is one having a wide bandgap and which therefore is transparent; the dye selected is one having a ground state within the bandgap of the semiconductor to generate carriers in the semiconductor, and a first excited state above the conduction band edge of the semiconductor to readily conduct electrons from the dye to the semiconductor; the reducing agent selected is one having a ground state above the ground state of the sensitizer to provide a plentiful source of electrons to the dye during current generation and thereby enhance the generation; and the metal for the thin-film layer of metal is selected to have a Fermi level in the vicinity of or above the ground state of the reducing agent to thereby amply supply electrons to the reducing agent.

  12. Photocurrent-voltage of a dye-sensitized nanocrystalline TiO2 solar cells influenced by N719 dye adsorption properties.

    PubMed

    Lee, Jae-Wook; Hwang, Kyung-Jun; Park, Dong-Won; Park, Kyung-Hee; Shim, Wang-Geun; Kim, Sang-Chai

    2007-11-01

    Titanium particles of single-phase anatase nanocrystallites were prepared by the hydrolysis of titanium tetraisopropoxide. A dye-sensitized solar cell (DSSC) was fabricated by adsorbing cis-bis(isothiocyanato)bis(2,2'-bipyridyl-4,4'-dicarboxylato)-ruthenium(II)bis-tetrabutylammonium dye (N719) onto TiO2 film. The samples were characterized by XRD, TEM, FE-SEM, AFM, and Brunauer-Emmett-Teller (BET) analysis. The influence of the acetic acid treatment of TiO2 electrode with different concentrations on the photovoltaic performance of DSSC was investigated. It was found that DSSC had better photoelectric performance when the TiO2 electrode was treated by acetic acid of 0.5 M. An equivalent circuit analysis using the one-diode model was used to evaluate the influences of adsorption quantity and acetic acid treatment on the energy conversion efficiency of DSSC. A nonlinear least-square optimization method was used to determine five model parameters. PMID:18047044

  13. Towards low temperature sintering methods for dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Murali, Sukanya

    Access to economically viable renewable energy sources is essential for the development of a globally sustainable society. Solar energy has a large potential to satisfy the future need for renewable energy sources. Dye sensitized solar cells are a third generation of photovoltaic technologies with the potential for low cost environmentally safe energy production. Commercialization of this technology requires that dye sensitized solar cells with higher efficiencies can be fabricated on flexible substrates. The commonly used material for the anode in a Dye Sensitized Solar Cell consists of titanium dioxide nanoparticles covered with a layer of light sensitizing dye. For efficient electron transport throughout the nanoparticle network, good particle interconnections are necessary. For low temperature processing these interconnections can be achieved through a hydrothermal process. The focus of this research is to understand at a fundamental level this reaction-based sintering process. A titanium alkoxide precursor was mixed with commercial titania nanoparticles and coated on a transparent conductive oxide substrate. The product of the hydrolysis and condensation of the alkoxide served to connect the nanoparticles thus improving the electrical conduction of the titania electrode; this was confirmed by solar cell testing and electrochemical impedance spectroscopy. To further understand the formation of interconnections during reactive sintering, a model system based on inert silica particles was investigated. Titanium alkoxide precursor was mixed with commercial silica particles and reacted. Three different types of silica particles were used: each with a different morphology. The silica-titania multilayers/powders were characterized using SEM, XRD and BET. The efficiency of DSSCs is higher when larger non-porous silica particles are used and thin nanocrystalline titania is coated on this superstructure. This gave insight into the locations where the reactive liquid

  14. Rose Bengal sensitized bilayered photoanode of nano-crystalline TiO2-CeO2 for dye-sensitized solar cell application

    NASA Astrophysics Data System (ADS)

    Sayyed, Suhail A. A. R.; Beedri, Niyamat I.; Kadam, Vishal S.; Pathan, Habib M.

    2016-08-01

    The present work deals with the study of TiO2-CeO2 bilayered photoanode with low-cost Rose Bengal (RB) dye as sensitizer for dye-sensitized solar cell application. The recombination reactions are reduced in bilayered TiO2-CeO2 photoanode as compared to the single-layered CeO2 photoanode. Once the electrons get transferred from lowest unoccupied molecular orbital level of RB dye to the conduction band (CB) of TiO2, then the possibilities of recombination of electrons with oxidized dye molecules or oxidized redox couple are reduced. This is because the CB position of CeO2 is higher than that of TiO2, which blocks the path of electrons. The electrochemical impedance spectroscopy (EIS) analysis shows negative shift in frequency for bilayered TiO2-CeO2 photoanode as compared to CeO2 photoanode. Hence, in bilayered photoanode lifetime of electrons is more than in single-layered photoanode, confirming reduction in recombination reactions. The X-ray diffraction patterns confirm both anatase TiO2 and CeO2 with crystalline size using Scherrer formula as 24 and 10 nm, respectively. The scanning electron microscopy images of photoanode show the porous structure useful for dye adsorption. The presence of Ti and Ce is confirmed by electron diffraction studies. The band gap values for TiO2 and CeO2 were calculated as 3.20 and 3.11 eV, respectively, using diffused reflectance spectroscopy. The bilayered TiO2-CeO2 photoanode showed open-circuit voltage ( V OC) ~500 mV and short-circuit photocurrent density ( J SC) ~0.29 mA/cm2 with fill factor (FF) ~62.17 %. There is increase in V OC and J SC values by 66.67 and 38.10 %, respectively, compared to RB-sensitized CeO2 photoanode.

  15. Photoelectrochemical Properties of Nanocrystalline Sb6O13, MgSb2O6, and ZnSb2O6-Based Electrodes for Dye-Sensitized Solar Cells

    NASA Astrophysics Data System (ADS)

    Jang, Jiyeon; Kim, Seung-Joo

    2012-10-01

    Three kinds of antimony compounds - Sb6O13, MgSb2O6 and ZnSb2O6 - were prepared in the form of nanocrystalline film and their photo-electrochemical properties were investigated. The preparation of Sb6O13 was based on thermolysis of a colloidal Sb2O5·4H2O suspension. MgSb2O6 and ZnSb2O6 were prepared via low-temperature hydrothermal methods. All the compounds exhibited semiconducting properties applicable to dye-sensitized solar cell (DSSC). The energy band gaps were estimated to be 3.39 eV for Sb6O13, 3.60 eV for MgSb2O6, and 3.31 eV for ZnSb2O6, respectively. After sensitization with a conventional ruthenium-dye (N719), Sb6O13-based solar cell exhibited the highest open circuit voltage (Voc = 0.76 V) whereas the Voc values (0.44-0.46 V) of MgSb2O6 and ZnSb2O6 are relatively low. The Voc values were proven to be related to the flat band potentials of the antimony compounds. The overall solar-to-electric energy conversion efficiencies were in the range of 0.7-1.0% under AM 1.5, 100 mW/cm2 illumination.

  16. Exploiting nanocarbons in dye-sensitized solar cells.

    PubMed

    Kavan, Ladislav

    2014-01-01

    Fullerenes, carbon nanotubes, nanodiamond, and graphene find various applications in the development of solar cells, including dye sensitized solar cells. Nanocarbons can be used as (1) active light-absorbing component, (2) current collector, (3) photoanode additive, or (4) counter electrode. Graphene-based materials have attracted considerable interest for catalytic counter electrodes, particularly in state-of-the-art dye sensitized solar cells with Co-mediators. The understanding of electrochemical charge-transfer at carbon surfaces is key to optimization of these solar cells, but the electrocatalysis on carbon surfaces is still a subject of conflicting debate. Due to the rich palette of problems at the interface of nanocarbons and photovoltaics, this review is selective rather than comprehensive. Its motivation was to highlight selected prospective inputs from nanocarbon science towards the development of novel dye sensitized solar cells with improved efficiency, durability, and cost. PMID:23729170

  17. Development of Flexible Dye-Sensitized Solar Cells

    NASA Astrophysics Data System (ADS)

    Fan, Xiaojuan

    2010-03-01

    We are developing a low cost and easy process to fabricate porous metal oxide thin films on flexible substrate for high performance dye-sensitized solar cells (DSSCs). The research addresses on the formulation of TiO2 precursor to create smooth and continuous porous thin films on large size plastic or metal foil substrates enabling excellent adhesion, robust mechanics, and chemical stability. The porous nanocrystalline TiO2 thin films are used as anode electrodes for attaching light sensitizers. The first trial is to blend a polymer to Ti alkoxide precursors at various concentrations. After depositing the mixture on the substrates, the substrates are baked, exposed to UV light, taken place wet or dry etch to remove polymers leading to a porous structure. An appropriate annealing process will be applied to TiO2 to turn it into crystalline. Alternative low temperature annealing method including steaming hydrothermal, plasma etches, and UV-ozone treatment will be tested with the annealing process controlled at low temperature.

  18. Dye-sensitized solar cells based on purple corn sensitizers

    NASA Astrophysics Data System (ADS)

    Phinjaturus, Kawin; Maiaugree, Wasan; Suriharn, Bhalang; Pimanpaeng, Samuk; Amornkitbamrung, Vittaya; Swatsitang, Ekaphan

    2016-09-01

    Natural dye extracted from husk, cob and silk of purple corn, were used for the first time as photosensitizers in dye sensitized solar cells (DSSCs). The dye sensitized solar cells fabrication process has been optimized in terms of solvent extraction. The resulting maximal efficiency of 1.06% was obtained from purple corn husk extracted by acetone. The ultraviolet-visible (UV-vis) spectroscopy, Fourier transform infrared spectroscopy (FTIR), electrochemical impedance spectroscopy (EIS) and incident photon-to-current efficiency (IPCE) were employed to characterize the natural dye and the DSSCs.

  19. Dye-Sensitization Of Nanocrystalline ZnO Thin Films

    NASA Astrophysics Data System (ADS)

    Ajimsha, R. S.; Tyagi, M.; Das, A. K.; Misra, P.; Kukreja, L. M.

    2010-12-01

    Nannocrystalline and nanoporus thin films of ZnO were synthesized on glass substrates by using wet chemical drop casting method. X-ray diffraction measurements on these samples confirmed the formation of ZnO nanocrystallites in hexagonal wurtzite phase with mean size of ˜20 nm. Photo sensitization of these nanostructured ZnO thin films was carried out using three types of dyes Rhodamine 6 G, Chlorophyll and cocktail of Rhodamine 6 G and Chlorophyll in 1:1 ratio. Dye sensitized ZnO thin films showed enhanced optical absorption in visible spectral region compared to the pristine ZnO thin films.

  20. Dye-Sensitization Of Nanocrystalline ZnO Thin Films

    SciTech Connect

    Ajimsha, R. S.; Tyagi, M.; Das, A. K.; Misra, P.; Kukreja, L. M.

    2010-12-01

    Nannocrystalline and nanoporus thin films of ZnO were synthesized on glass substrates by using wet chemical drop casting method. X-ray diffraction measurements on these samples confirmed the formation of ZnO nanocrystallites in hexagonal wurtzite phase with mean size of {approx}20 nm. Photo sensitization of these nanostructured ZnO thin films was carried out using three types of dyes Rhodamine 6 G, Chlorophyll and cocktail of Rhodamine 6 G and Chlorophyll in 1:1 ratio. Dye sensitized ZnO thin films showed enhanced optical absorption in visible spectral region compared to the pristine ZnO thin films.

  1. Aerogel tempelated ZnO dye-sensitized solar cells.

    SciTech Connect

    Hamann, T. W.; Martinson , A. B. E.; Elam, J. W.; Pellin, M. J.; Hupp, J. T.; Materials Science Division; Northwestern Univ.

    2008-01-01

    Atomic layer deposition is employed to conformally coat low density, high surface area aerogel films with ZnO. The ZnO/aerogel membranes are incorporated as photoanodes in dye-sensitized solar cells, which exhibit excellent power efficiencies of up to 2.4% under 100 mW cm{sup -2} light intensity.

  2. Highly efficient photocathodes for dye-sensitized tandem solar cells.

    PubMed

    Nattestad, A; Mozer, A J; Fischer, M K R; Cheng, Y-B; Mishra, A; Bäuerle, P; Bach, U

    2010-01-01

    Thin-film dye-sensitized solar cells (DSCs) based on mesoporous semiconductor electrodes are low-cost alternatives to conventional silicon devices. High-efficiency DSCs typically operate as photoanodes (n-DSCs), where photocurrents result from dye-sensitized electron injection into n-type semiconductors. Dye-sensitized photocathodes (p-DSCs) operate in an inverse mode, where dye-excitation is followed by rapid electron transfer from a p-type semiconductor to the dye (dye-sensitized hole injection). Such p-DSCs and n-DSCs can be combined to construct tandem solar cells (pn-DSCs) with a theoretical efficiency limitation well beyond that of single-junction DSCs (ref. 4). Nevertheless, the efficiencies of such tandem pn-DSCs have so far been hampered by the poor performance of the available p-DSCs (refs 3, 5-15). Here we show for the first time that p-DSCs can convert absorbed photons to electrons with yields of up to 96%, resulting in a sevenfold increase in energy conversion efficiency compared with previously reported photocathodes. The donor-acceptor dyes, studied as photocathodic sensitizers, comprise a variable-length oligothiophene bridge, which provides control over the spatial separation of the photogenerated charge carriers. As a result, charge recombination is decelerated by several orders of magnitude and tandem pn-DSCs can be constructed that exceed the efficiency of their individual components. PMID:19946281

  3. Highly efficient photocathodes for dye-sensitized tandem solar cells

    NASA Astrophysics Data System (ADS)

    Nattestad, A.; Mozer, A. J.; Fischer, M. K. R.; Cheng, Y.-B.; Mishra, A.; Bäuerle, P.; Bach, U.

    2010-01-01

    Thin-film dye-sensitized solar cells (DSCs) based on mesoporous semiconductor electrodes are low-cost alternatives to conventional silicon devices. High-efficiency DSCs typically operate as photoanodes (n-DSCs), where photocurrents result from dye-sensitized electron injection into n-type semiconductors. Dye-sensitized photocathodes (p-DSCs) operate in an inverse mode, where dye-excitation is followed by rapid electron transfer from a p-type semiconductor to the dye (dye-sensitized hole injection). Such p-DSCs and n-DSCs can be combined to construct tandem solar cells (pn-DSCs) with a theoretical efficiency limitation well beyond that of single-junction DSCs (ref. 4). Nevertheless, the efficiencies of such tandem pn-DSCs have so far been hampered by the poor performance of the available p-DSCs (refs 3, 5-15). Here we show for the first time that p-DSCs can convert absorbed photons to electrons with yields of up to 96%, resulting in a sevenfold increase in energy conversion efficiency compared with previously reported photocathodes. The donor-acceptor dyes, studied as photocathodic sensitizers, comprise a variable-length oligothiophene bridge, which provides control over the spatial separation of the photogenerated charge carriers. As a result, charge recombination is decelerated by several orders of magnitude and tandem pn-DSCs can be constructed that exceed the efficiency of their individual components.

  4. Nano-TiO2 for dye-sensitized solar cells.

    PubMed

    Baraton, Marie-Isabelle

    2012-01-01

    Photovoltaics are amongst the most popular renewable energy sources and low-cost solar cell technologies are making progress to the market. Research on dye-sensitized solar cells (DSSCs) usually based on nanocrystalline TiO2 has been extensively pursued, and the number of papers and patents published in this area has grown exponentially over the last ten years. Research efforts have largely focused on the optimization of the dye, but recently the TiO2 nanocrystalline electrode itself has attracted more attention. It has been shown that particle size and shape, crystallinity, surface morphology and chemistry of the TiO2 material are key parameters to be controlled for optimized performance of the solar cell. This article will review the most recent research activities on nanostructured TiO2 for improvement of the DSSC performance. PMID:22023080

  5. Metal oxide-encapsulated dye-sensitized photoanodes for dye-sensitized solar cells

    DOEpatents

    Hupp, Joseph T.; Son, Ho-Jin

    2016-01-12

    Dye-sensitized semiconducting metal oxide films for photoanodes, photoanodes incorporating the films and DSCs incorporating the photoanodes are provided. Also provided are methods for making the dye sensitized semiconducting metal oxide films. The methods of making the films are based on the deposition of an encapsulating layer of a semiconducting metal oxide around the molecular anchoring groups of photosensitizing dye molecules adsorbed to a porous film of the semiconducting metal oxide. The encapsulating layer of semiconducting metal oxide is formed in such a way that it is not coated over the chromophores of the adsorbed dye molecules and, therefore, allows the dye molecules to remain electrochemically addressable.

  6. Weavable dye sensitized solar cells exploiting carbon nanotube yarns

    NASA Astrophysics Data System (ADS)

    Velten, Josef; Kuanyshbekova, Zharkynay; Göktepe, Özer; Göktepe, Fatma; Zakhidov, Anvar

    2013-05-01

    Weavable Dye Sensitized Solar Cells (DSSC) made with flexible yarns of conductive multiwalled carbon nanotubes (MWNTs) were produced having a power conversion efficiency above 3%. This was achieved with a specific design and careful consideration of the yarn function in the DSSC. Fermat yarns of MWNTs individually coated with mesoporous TiO2 layer were twisted together and coated with more mesoporous TiO2 to create a 3 dimensional photo electrode to overcome electron diffusion length issues. Archimedian yarns of MWNTs coated with a thin layer of platinum worked as a counter electrode to complete the architecture used in this DSSC.

  7. Digital Printing of Titanium Dioxide for Dye Sensitized Solar Cells

    PubMed Central

    Cherrington, Ruth; Wood, Benjamin Michael; Salaoru, Iulia; Goodship, Vannessa

    2016-01-01

    Silicon solar cell manufacturing is an expensive and high energy consuming process. In contrast, dye sensitized solar cell production is less environmentally damaging with lower processing temperatures presenting a viable and low cost alternative to conventional production. This paper further enhances these environmental credentials by evaluating the digital printing and therefore additive production route for these cells. This is achieved here by investigating the formation and performance of a metal oxide photoelectrode using nanoparticle sized titanium dioxide. An ink-jettable material was formulated, characterized and printed with a piezoelectric inkjet head to produce a 2.6 µm thick layer. The resultant printed layer was fabricated into a functioning cell with an active area of 0.25 cm2 and a power conversion efficiency of 3.5%. The binder-free formulation resulted in a reduced processing temperature of 250 °C, compatible with flexible polyamide substrates which are stable up to temperatures of 350 ˚C. The authors are continuing to develop this process route by investigating inkjet printing of other layers within dye sensitized solar cells. PMID:27166761

  8. Digital Printing of Titanium Dioxide for Dye Sensitized Solar Cells.

    PubMed

    Cherrington, Ruth; Wood, Benjamin Michael; Salaoru, Iulia; Goodship, Vannessa

    2016-01-01

    Silicon solar cell manufacturing is an expensive and high energy consuming process. In contrast, dye sensitized solar cell production is less environmentally damaging with lower processing temperatures presenting a viable and low cost alternative to conventional production. This paper further enhances these environmental credentials by evaluating the digital printing and therefore additive production route for these cells. This is achieved here by investigating the formation and performance of a metal oxide photoelectrode using nanoparticle sized titanium dioxide. An ink-jettable material was formulated, characterized and printed with a piezoelectric inkjet head to produce a 2.6 µm thick layer. The resultant printed layer was fabricated into a functioning cell with an active area of 0.25 cm(2) and a power conversion efficiency of 3.5%. The binder-free formulation resulted in a reduced processing temperature of 250 °C, compatible with flexible polyamide substrates which are stable up to temperatures of 350 ˚C. The authors are continuing to develop this process route by investigating inkjet printing of other layers within dye sensitized solar cells. PMID:27166761

  9. Aggregated TiO2 Based Nanotubes for Dye Sensitized Solar Cells

    SciTech Connect

    Nie, Zimin; Zhou, Xiaoyuan; Zhang, Qifeng; Cao, Guozhong; Liu, Jun

    2013-11-01

    One-dimensional (1D) semiconducting oxides have attracted great attention for dye sensitized solar cells (DSCs), but the overall performance is still quite limited as compared to TiO2 nanocrystalline DSCs. Here, we report the synthesis of aggregated TiO2 based nanotubes with controlled morphologies and crystalline structures to obtain an overall power conversion efficiency of 9.9% using conventional dye without any additional chemical treatment steps. The high efficiency is attributed to the unique aggregate structure for light harvesting, optimized high surface area, and good crystallinity of the nanotube aggregates obtained through proper thermal annealing. This study demonstrates that high efficiency DSCs can be obtained with 1D nanomaterials, and provides lessons on the importance of optimizing both the nanocrystalline structure and the overall microscale morphology.

  10. Photoconductivity of an inorganic/organic composite containing dye-sensitized nanocrystalline titanium dioxide

    NASA Astrophysics Data System (ADS)

    Kocher, M.; Däubler, T. K.; Harth, E.; Scherf, U.; Gügel, A.; Neher, D.

    1998-02-01

    The photophysical properties of solid films of an inorganic/organic composite composed of dye-sensitized nanocrystalline titanium dioxide (TiO2) particles, a conjugated polymer, and a [60] fullerene derivative have been investigated. Large charge collection efficiencies of up to 10% at a field of only 10 V/μm were observed. The photoaction spectrum of the composite is interpreted in terms of three major contributions: a weak photocurrent due to the absorption of photons by the polymer, photogeneration of charges involving the fullerene, and a broad region below the onset of the polymer absorption which involves photophysical processes in the dye-loaded TiO2 nanoparticles.

  11. Green grasses as light harvesters in dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Shanmugam, Vinoth; Manoharan, Subbaiah; Sharafali, A.; Anandan, Sambandam; Murugan, Ramaswamy

    2015-01-01

    Chlorophylls, the major pigments presented in plants are responsible for the process of photosynthesis. The working principle of dye sensitized solar cell (DSSC) is analogous to natural photosynthesis in light-harvesting and charge separation. In a similar way, natural dyes extracted from three types of grasses viz. Hierochloe Odorata (HO), Torulinium Odoratum (TO) and Dactyloctenium Aegyptium (DA) were used as light harvesters in dye sensitized solar cells (DSSCs). The UV-Vis absorption spectroscopy, Fourier transform infrared (FT-IR), and liquid chromatography-mass spectrometry (LC-MS) were used to characterize the dyes. The electron transport mechanism and internal resistance of the DSSCs were investigated by the electrochemical impedance spectroscopy (EIS). The performance of the cells fabricated with the grass extract shows comparable efficiencies with the reported natural dyes. Among the three types of grasses, the DSSC fabricated with the dye extracted from Hierochloe Odorata (HO) exhibited the maximum efficiency. LC-MS investigations indicated that the dominant pigment present in HO dye was pheophytin a (Pheo a).

  12. Artificial evolution of coumarin dyes for dye sensitized solar cells.

    PubMed

    Venkatraman, Vishwesh; Abburu, Sailesh; Alsberg, Bjørn Kåre

    2015-11-01

    The design and discovery of novel molecular structures with optimal properties has been an ongoing effort for materials scientists. This field has in general been dominated by experiment driven trial-and-error approaches that are often expensive and time-consuming. Here, we investigate if a de novo computational design methodology can be applied to the design of coumarin-based dye sensitizers with improved properties for use in Grätzel solar cells. To address the issue of synthetic accessibility of the designed compounds, a fragment-based assembly is employed, wherein the combination of chemical motifs (derived from the existing databases of structures) is carried out with respect to user-adaptable set of rules. Rather than using computationally intensive density functional theory (DFT)/ab initio methods to screen candidate dyes, we employ quantitative structure-property relationship (QSPR) models (calibrated from empirical data) for rapid estimation of the property of interest, which in this case is the product of short circuit current (Jsc) and open circuit voltage (Voc). Since QSPR models have limited validity, pre-determined applicability domain criteria are used to prevent unacceptable extrapolation. DFT analysis of the top-ranked structures provides supporting evidence of their potential for dye sensitized solar cell applications. PMID:26428071

  13. Asymmetric Zinc Phthalocyanines as Dye-Sensitized Solar Cells

    NASA Astrophysics Data System (ADS)

    Tunc, Gulenay; Yavuz, Yunus; Gurek, Aysegul; Canimkurbey, Betul; Kosemen, Arif; San, Sait Eren; Ahsen, Vefa

    Dye-sensitized solar cells (DSSCs) have received increasing attention due to their high incident to photon efficiency, easy fabrication and low production cost . Tremendous research efforts have been devoted to the development of new and efficient sensitizers suitable for practical use. In TiO2-based DSSCs, efficiencies of up to 11.4% under simulated sunlight have been obtained with rutheniumepolypyridyl complexes. However, the main drawback of ruthenium complexes is the lack of absorption in the red region of the visible light and the high cost. For this reason, dyes with large and stable p-conjugated systems such as porphyrins and phthalocyanines are important classes of potential sensitizers for highly efficient DSSCs. Phthalocyanines (Pcs) have been widely used as sensitizers because of their improved light-harvesting properties in the far red- and near-IR spectral regions and their extraordinary robustness [1]. In this work, a series of asymmetric Zn(II) Pcs bearing a carboxylic acid group and six hexylthia groups either at the peripheral or non-peripheral positions have been designed and synthesized to investigate the influence of the COOH group and the positions of hexylthia groups on the dye-sensitized solar cell (DSSC) performance.

  14. Quasi Solid Polymer Electrolytes for Dye Sensitized Solar Cells

    NASA Astrophysics Data System (ADS)

    Dissanayake, M. A. K. Lakshman

    2013-07-01

    Dye-sensitized solar cell (DSSC) has been considered as an alternative to the conventional silicon solar cell because of low cost, easy fabrication and relatively high conversion efficiency. A DSSC consists of a dye-sensitized nanoparticulated TiO2 electrode, an electrolyte containing redox couple and a Pt coated counter electrode. Such solar cells based on an I-/I3- redox couple in an organic solvent usually have conversion efficiencies reaching around 11%. However, a major drawback of these solution based solar cells, originally developed by Gratzel and coworkers is the lack of long-term stability due to liquid leakage, usage of volatile liquids such as acetonitrile, electrode corrosion, and photodecomposition of the dye in the solvent medium. Therefore considerable research efforts have been made in recent years to replace the liquid electrolytes with solid polymer or quasi-solid polymer (gel) electrolytes. Among these approaches, the use of gel polymer electrolytes appears to give rise to successful results in terms of conversion efficiency. Conventional poly (ethylene oxide)(PEO)-based solid polymer electrolytes exhibit poor ionic conductivities at room temperature, which is not sufficient for practical applications. Therefore, most of the recent studies have been directed to the preparation and characterization of gel polymer electrolytes which exhibit higher ionic conductivity at ambient temperature while maintain quai-solid structure. These gel polymer electrolytes prepared by incorporating a liquid electrolyte into a matrix polymer such as polyacrylonitrile(PAN), poly(vinylidene fluoride)(PVdF), poly (methyl methacrylate) (PMMA) and PEO have been employed in quasi-solid-state DSSCs to achieve power conversion efficiencies of more than 5%. Significant improvements have been achieved in recent years by modifications of the electrolytes by optimizing the ionic salt, introducing additives such as inorganic nanofillers, organic molecules and ionic liquids in

  15. Review on Metallic and Plastic Flexible Dye Sensitized Solar Cell

    NASA Astrophysics Data System (ADS)

    Yugis, A. R.; Mansa, R. F.; Sipaut, C. S.

    2015-04-01

    Dye sensitized solar cells (DSSCs) are a promising alternative for the development of a new generation of photovoltaic devices. DSSCs have promoted intense research due to their low cost and eco-friendly advantage over conventional silicon-based crystalline solar cells. In recent years, lightweight flexible types of DSSCs have attracted much intention because of drastic reduction in production cost and more extensive application. The substrate that used as electrode of the DSSCs has a dominant impact on the methods and materials that can be applied to the cell and consequently on the resulting performance of DSSCs. Furthermore, the substrates influence significantly the stability of the device. Although the power conversion efficiency still low compared to traditional glass based DSSCs, flexible DSSCs still have potential to be the most efficient and easily implemented technology.

  16. Device modeling of dye-sensitized solar cells.

    PubMed

    Bisquert, Juan; Marcus, Rudolph A

    2014-01-01

    We review the concepts and methods of modeling of the dye-sensitized solar cell, starting from fundamental electron transfer theory, and using phenomenological transport-conservation equations. The models revised here are aimed at describing the components of the current-voltage curve of the solar cell, based on small perturbation experimental methods, and to such an end, a range of phenomena occurring in the nanoparticulate electron transport materials, and at interfaces, are covered. Disorder plays a major role in the definition of kinetic parameters, and we introduce single particle as well as collective function definitions of diffusion coefficient and electron lifetime. Based on these fundamental considerations, applied tools of analysis of impedance spectroscopy are described, and we outline in detail the theory of recombination via surface states that is successful to describe the measured recombination resistance and lifetime. PMID:24085559

  17. Dye sensitized solar cells with carbon black as counter electrodes

    NASA Astrophysics Data System (ADS)

    Lin, Chi-Feng; Chou, Yu-Chen; Haung, Jhang-Fu; Chen, Pin-Hung; Han, Hsieh-Cheng; Chiu, Kuo-Yuan; Su, Yuhlong Oliver

    2016-03-01

    In this experiment, we use carbon black as counter electrodes to replace the conventional platinum electrodes in dye sensitized solar cell (DSSC). The electrical properties and device efficiency with carbon black counter electrodes with various concentrations, and under the annealing temperature from 100 to 500 °C are discussed. After the proper annealing process, the conductivity and redoxing ability of the carbon black is improved, resulted in the enhancement of the electrical characteristics, especially fill factor, of the device. The highest device efficiency was 7.28% with the JSC of 14.70 mA/cm2, VOC of 0.75 V, and fill factor of 0.67 under 1-sun AM 1.5G solar illumination.

  18. Comparison of Dye-Sensitized Rutile- and Anatase-Based TiO2 Solar Cells

    SciTech Connect

    Park, N. G.; van de Lagemaat, J.; Frank, A. J.

    2000-01-01

    The objective of this work is to develop and optimize the new dye-sensitized solar cell technology. In view of the infancy of rutile material development for solar cells, the PV response of the dye-sensitized rutile-based solar cell is remarkably close to that of the anatase-based cell.

  19. Natural dye -sensitized mesoporous ZnO solar cell

    NASA Astrophysics Data System (ADS)

    Wu, Qishuang; Shen, Yue; Wu, Guizhi; Li, Linyu; Cao, Meng; Gu, Feng

    2010-10-01

    Natural dye-sensitized solar cells (N-DSSCs) were assembled using chlorophyll sensitized mesoporous ZnO (based on FTO) as the photoanode and platinum plate as the cathode. The natural dyes (chlorophyll) were extracted from spinach by simple procedure. The absorption spectrum and fluorescence spectrum of chlorophyll were studied. Mesoporous ZnO (m-ZnO) applied to the N-DSSCs was synthesized through hydrothermal method. The structures and morphologies were characterized by X-ray Diffraction (XRD) and diffuse reflection. The results indicated that the samples had an average pore size of 17 nm and the m-ZnO was hexagonal wurtzite structure. The performances of the N-DSSCs were investigated under AM 1.5G illumination. The Voc of the N-DSSCs was about 480mv, and the Isc was about 470μA. The performance of the N-DSSCs could be further improved by adjusting its structure.

  20. Natural dye -sensitized mesoporous ZnO solar cell

    NASA Astrophysics Data System (ADS)

    Wu, Qishuang; Shen, Yue; Wu, Guizhi; Li, Linyu; Cao, Meng; Gu, Feng

    2011-02-01

    Natural dye-sensitized solar cells (N-DSSCs) were assembled using chlorophyll sensitized mesoporous ZnO (based on FTO) as the photoanode and platinum plate as the cathode. The natural dyes (chlorophyll) were extracted from spinach by simple procedure. The absorption spectrum and fluorescence spectrum of chlorophyll were studied. Mesoporous ZnO (m-ZnO) applied to the N-DSSCs was synthesized through hydrothermal method. The structures and morphologies were characterized by X-ray Diffraction (XRD) and diffuse reflection. The results indicated that the samples had an average pore size of 17 nm and the m-ZnO was hexagonal wurtzite structure. The performances of the N-DSSCs were investigated under AM 1.5G illumination. The Voc of the N-DSSCs was about 480mv, and the Isc was about 470μA. The performance of the N-DSSCs could be further improved by adjusting its structure.

  1. Plasmonic nanoparticles enhanced dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Xu, Qi; Liu, Fang; Meng, Weisi; Huang, Yidong

    2013-12-01

    Here we present investigations on utilizing two kinds of plasmonic nanoparticles (NPs) to enhance the efficiency of dye sensitized solar cells (DSCs). The Au@PVP NPs is proposed and present the specialty of adhesiveness to dye molecules, which could help to localize additional dye molecules near the plasmonic NPs, hence increasing the optical absorption consequently the power conversion efficiency (PCE) of the DSCs by 30% from 3.3% to 4.3%. Meanwhile, an irregular Au-Ag alloy popcorn-shaped NPs (popcorn NPs) with plenty of fine structures is also proposed and realized to enhance the light absorption of DSC. A pronounced absorption enhancement in a broadband wavelength range is observed due to the excitation of localized surface plasmon at different wavelengths. The PCE is enhanced by 32% from 5.94% to 7.85%.

  2. Efficiency Records in Mesoscopic Dye-Sensitized Solar Cells.

    PubMed

    Albero, Josep; Atienzar, Pedro; Corma, Avelino; Garcia, Hermenegildo

    2015-08-01

    The aim of the present review article is to show the progress achieved in the efficiency of dye-sensitized solar cells (DSSCs) by evolution in the structure and composition of the dye. After an initial brief description of DSSCs and the operating mechanism the major part of the present article is organized according to the type of dye, trying to show the logic in the variation of the dye structure in order to achieve strong binding on the surface of the layer of nanoparticulate TiO2 , efficient interfacial electron injection between the excited dye and the semiconductor, and minimization of the unwanted dark current processes. Besides metal complexes, including polypyridyls and nitrogenated macro rings, organic dyes and inorganic light harvesters such as quantum dots and perovskites have also been included in the review. The last section summarizes the current state of the art and provides an overview on future developments in the field. PMID:26183911

  3. Carbon Nanotubes for Dye-Sensitized Solar Cells.

    PubMed

    Batmunkh, Munkhbayar; Biggs, Mark J; Shapter, Joseph G

    2015-07-01

    As one type of emerging photovoltaic cell, dye-sensitized solar cells (DSSCs) are an attractive potential source of renewable energy due to their eco-friendliness, ease of fabrication, and cost effectiveness. However, in DSSCs, the rarity and high cost of some electrode materials (transparent conducting oxide and platinum) and the inefficient performance caused by slow electron transport, poor light-harvesting efficiency, and significant charge recombination are critical issues. Recent research has shown that carbon nanotubes (CNTs) are promising candidates to overcome these issues due to their unique electrical, optical, chemical, physical, as well as catalytic properties. This article provides a comprehensive review of the research that has focused on the application of CNTs and their hybrids in transparent conducting electrodes (TCEs), in semiconducting layers, and in counter electrodes of DSSCs. At the end of this review, some important research directions for the future use of CNTs in DSSCs are also provided. PMID:25864907

  4. Highly efficient monolithic dye-sensitized solar cells.

    PubMed

    Kwon, Jeong; Park, Nam-Gyu; Lee, Jun Young; Ko, Min Jae; Park, Jong Hyeok

    2013-03-01

    Monolithic dye-sensitized solar cells (M-DSSCs) provide an effective way to reduce the fabrication cost of general DSSCs since they do not require transparent conducting oxide substrates for the counter electrode. However, conventional monolithic devices have low efficiency because of the impediments resulting from counter electrode materials and spacer layers. Here, we demonstrate highly efficient M-DSSCs featuring a highly conductive polymer combined with macroporous polymer spacer layers. With M-DSSCs based on a PEDOT/polymer spacer layer, a power conversion efficiency of 7.73% was achieved, which is, to the best of our knowledge, the highest efficiency for M-DSSCs to date. Further, PEDOT/polymer spacer layers were applied to flexible DSSCs and their cell performance was investigated. PMID:23432389

  5. Dye Sensitized Solar Cells for Economically Viable Photovoltaic Systems.

    PubMed

    Jung, Hyun Suk; Lee, Jung-Kun

    2013-05-16

    TiO2 nanoparticle-based dye sensitized solar cells (DSSCs) have attracted a significant level of scientific and technological interest for their potential as economically viable photovoltaic devices. While DSSCs have multiple benefits such as material abundance, a short energy payback period, constant power output, and compatibility with flexible applications, there are still several challenges that hold back large scale commercialization. Critical factors determining the future of DSSCs involve energy conversion efficiency, long-term stability, and production cost. Continuous advancement of their long-term stability suggests that state-of-the-art DSSCs will operate for over 20 years without a significant decrease in performance. Nevertheless, key questions remain in regards to energy conversion efficiency improvements and material cost reduction. In this Perspective, the present state of the field and the ongoing efforts to address the requirements of DSSCs are summarized with views on the future of DSSCs. PMID:26282979

  6. Halogen Bonding Promotes Higher Dye-Sensitized Solar Cell Photovoltages.

    PubMed

    Simon, Sarah J C; Parlane, Fraser G L; Swords, Wesley B; Kellett, Cameron W; Du, Chuan; Lam, Brian; Dean, Rebecca K; Hu, Ke; Meyer, Gerald J; Berlinguette, Curtis P

    2016-08-24

    We report here an enhancement in photovoltage for dye-sensitized solar cells (DSSCs) where halogen-bonding interactions exist between a nucleophilic electrolyte species (I(-)) and a photo-oxidized dye immobilized on a TiO2 surface. The triarylamine-based dyes under investigation showed larger rate constants for dye regeneration (kreg) by the nucleophilic electrolyte species when heavier halogen substituents were positioned on the dye. The open-circuit voltages (VOC) tracked these kreg values. This analysis of a homologous series of dyes that differ only in the identity of two halogen substituents provides compelling evidence that the DSSC photovoltage is sensitive to kreg. This study also provides the first direct evidence that halogen-bonding interactions between the dye and the electrolyte can bolster DSSC performance. PMID:27518595

  7. Optimizing the Performance of a Plastic Dye Sensitized Solar Cell

    SciTech Connect

    Lee, B.; Buchholz, D.; Guo, P.; Hwang, D.; Chang, R.P.H.

    2011-05-19

    This article describes that a fluorine plasma treatment can increase the nanopore filling of a plastic electrolyte in a dye-sensitized solar cell to improve its performance. The one-step fluorine treatment can be used in a controlled way to increase the size of nanopores and nanochannels in the TiO{sub 2} nanoparticle electrode and, at the same time, passivate the TiO{sub 2} nanoparticle surfaces. In combination with the fluorine treatment, a sequential electrolyte filling process has been developed that allows the overall cell conversion efficiency to be increased by as much as 25%. The plastic-based electrolyte cells are found to be much more stable compared with their counterpart, the liquid electrolyte cells. Using this new process, and in combination with a photon confinement scheme, the overall cell efficiency can reach to about 9% using a masked frame measurement technique.

  8. Ruthenium(II) multi carboxylic acid complexes: chemistry and application in dye sensitized solar cells.

    PubMed

    Shahroosvand, Hashem; Nasouti, Fahimeh; Sousaraei, Ahmad

    2014-04-01

    Novel ruthenium multi carboxylic complexes (RMCCs) have been synthesized by using ruthenium nitrosyl nitrate, 1,2,4,5-benzenetetracarboxylic acid (H4btec) and 4,7-diphenyl-1,10-phenanthroline (BPhen) as photosensitizers for titanium dioxide semiconductor solar cells. The complexes were characterized by (1)H-NMR, FT-IR, UV-Vis, ICP and CHN analyses. The reaction details and features were then described. SEM analysis revealed that the penetration of dyes into the pores of the nanocrystalline TiO2 surface was improved by increasing the number of btec units. The solar energy to electricity conversion efficiency of complexes shows that the number of attached carboxylates on a dye has an influence on the photoelectrochemical properties of the dye-sensitized electrode. An incident photon-to-current conversion efficiency (IPCE) of 13% at 510 nm was obtained for ruthenium complexes with three btec units. PMID:24500312

  9. Progress in nanostructured photoanodes for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Liu, Xueyang; Fang, Jian; Liu, Yong; Lin, Tong

    2016-05-01

    Solar cells represent a principal energy technology to convert light into electricity. Commercial solar cells are at present predominately produced by single- or multi-crystalline silicon wafers. The main drawback to silicon-based solar cells, however, is high material and manufacturing costs. Dye-sensitized solar cells (DSSCs) have attracted much attention during recent years because of the low production cost and other advantages. The photoanode (working electrode) plays a key role in determining the performance of DSSCs. In particular, nanostructured photoanodes with a large surface area, high electron transfer efficiency, and low electron recombination facilitate to prepare DSSCs with high energy conversion efficiency. In this review article, we summarize recent progress in the development of novel photoanodes for DSSCs. Effect of semiconductor material (e.g. TiO2, ZnO, SnO2, N2O5, and nano carbon), preparation, morphology and structure (e.g. nanoparticles, nanorods, nanofibers, nanotubes, fiber/particle composites, and hierarchical structure) on photovoltaic performance of DSSCs is described. The possibility of replacing silicon-based solar cells with DSSCs is discussed.

  10. Progress in nanostructured photoanodes for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Liu, Xueyang; Fang, Jian; Liu, Yong; Lin, Tong

    2016-09-01

    Solar cells represent a principal energy technology to convert light into electricity. Commercial solar cells are at present predominately produced by single- or multi-crystalline silicon wafers. The main drawback to silicon-based solar cells, however, is high material and manufacturing costs. Dye-sensitized solar cells (DSSCs) have attracted much attention during recent years because of the low production cost and other advantages. The photoanode (working electrode) plays a key role in determining the performance of DSSCs. In particular, nanostructured photoanodes with a large surface area, high electron transfer efficiency, and low electron recombination facilitate to prepare DSSCs with high energy conversion efficiency. In this review article, we summarize recent progress in the development of novel photoanodes for DSSCs. Effect of semiconductor material (e.g. TiO2, ZnO, SnO2, N2O5, and nano carbon), preparation, morphology and structure (e.g. nanoparticles, nanorods, nanofibers, nanotubes, fiber/particle composites, and hierarchical structure) on photovoltaic performance of DSSCs is described. The possibility of replacing silicon-based solar cells with DSSCs is discussed.

  11. Enhancement of Spectral Response of Dye-Sensitized Solar Cells

    NASA Astrophysics Data System (ADS)

    Chang, Shuai

    Dye-Sensitized solar cell (DSSC) is a class of third-generation solar devices. A notable feature of DSSC is that it can be manufactured by solution-based approach; this non-vacuum processing renders significant reduction in manufacturing costs. Different from conventional solar cells, in a DSSC, mesoporous semiconductor film with large surface areas is utilized for anchoring dye molecules, serving as light absorbing layer. Dye sensitizers play an important role in determining the final performance in DSSCs. Since the first highly-efficient DSSC was reported in 1991 sensitized by a ruthenium-based dye, numerous researchers have been focused on the development and characterization of various kinds of dyes for the applications in DSSCs. These include mainly metal complexes dyes, organic dyes, porphyrins and phthalocyanines dyes. The first part of my thesis work is to develop and test new dyes for DSSCs and a series of phenothiazine-based organic dyes and new porphyrin dyes are reported during the process. It has been realized that extending the response of dye sensitizers to a wider range of the solar spectrum is a key step in further improving the device efficiency. Typically, there are two ways for expanding the strong spectral response of DSSCs from visible to far red/NIR region. One approach is called co-sensitization. Herein, we demonstrate a new co-sensitization concept where small molecules is used to insert the interstitial site of between the pre-adsorbed large molecules. In this case, the co-adsorbed small ones is found to improve the light response and impede the back recombination, finally leading to the power conversion efficiency over 10% in conventional DSSC devices and a record-equaling efficiency of 9.2% in quasi-solid-state devices. I also implemented graphene sheets in the anode films for better charge transfer efficiency and break the energy conversion limit of co-sensitization in DSSCs. The optimal configuration between porphyrin dyes and

  12. Vegetable-based dye-sensitized solar cells.

    PubMed

    Calogero, Giuseppe; Bartolotta, Antonino; Di Marco, Gaetano; Di Carlo, Aldo; Bonaccorso, Francesco

    2015-05-21

    There is currently a large effort to improve the performance of low cost renewable energy devices. Dye-sensitized solar cells (DSSCs) are emerging as one of the most promising low cost photovoltaic technologies, addressing "secure, clean and efficient solar energy conversion". Vegetable dyes, extracted from algae, flowers, fruit and leaves, can be used as sensitizers in DSSCs. Thus far, anthocyanin and betalain extracts together with selected chlorophyll derivatives are the most successful vegetable sensitizers. This review analyses recent progress in the exploitation of vegetable dyes for solar energy conversion and compares them to the properties of synthetic dyes. We provide an in-depth discussion on the main limitation of cell performance e.g. dye degradation, effective electron injection from the dye into the conduction band of semiconducting nanoparticles, such as titanium dioxide and zinc oxide, outlining future developments for the use of vegetable sensitizers in DSSCs. We also discuss the cost of vegetable dyes and how their versatility can boost the advancement of new power management solutions, especially for their integration in living environments, making the practical application of such systems economically viable. Finally, we present our view on future prospects in the development of synthetic analogues of vegetable dyes as sensitizers in DSSCs. PMID:25855097

  13. Parallel Tandems of Dye Sensitized Solar Cells with CNT Collector

    NASA Astrophysics Data System (ADS)

    Velten, Josef; Yuan, Chao-Chen; Zakhidov, Anvar

    2009-03-01

    In this presentation, we demonstrate the fabrication of monolithic parallel tandem dye sensitized solar cells using a semitransparent layer of carbon nanotubes. Each DSC sub-cell has titania photoelectrode with two different dyes: N 719 and N 749, which absorb light in different parts of solar spectrum. This layer of carbon nanotubes laminated on highly porous polymeric Millipore filter acts as both the collector of charge carrier and as the catalyst of the I/I3^- redox reaction that completes the function of the cell, overall allowing easier fabrication for tandem solar cell devices, with a potential for creating flexible devices in the future. The parallel tandem shows the total photocurrent which is nearly the sum of two Isc currents of constituent cells, and total Voc, which is average of two Voc, while conventional in-series DSC tandems show the lowest Voc and slightly increased Isc[1]. Thus the higher efficiency can be achieved in parallel DSC tandems, and we discuss the physical reasons for this effect. [1] Yanagida, et.al. J. of Photochemistry and Photobiology A: Chemistry Volume 164, Issues 1-3, 1 June 2004, Pages 33-39

  14. Performance of Caesalpinia sappan heartwood extract as photo sensitizer for dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Ananth, S.; Vivek, P.; Saravana Kumar, G.; Murugakoothan, P.

    2015-02-01

    A natural dye extracted from Caesalpinia sappan heartwood was used as photo sensitizer for the first time to fabricate titanium dioxide (TiO2) nanoparticles based dye sensitized solar cells. Brazilin and brazilein are the major pigments present in the natural dye and their optimized molecular structure were calculated using Density functional theory (DFT) at 6-31G (d) level. The HOMO-LUMO were performed to reveal the energy gap using optimized structure. Pure TiO2 nanoparticles in anatase phase were synthesized by sol-gel technique. The pure and natural dye sensitized TiO2 nanoparticles were subjected to structural, optical, spectral and morphological studies. Low cost and environment friendly dye sensitized solar cells were fabricated using natural dye sensitized TiO2 based photo anode. The solar light to electron conversion efficiency of Caesalpinia sappan heartwood extract sensitized dye sensitized solar cell is 1.1%.

  15. Transistorlike behavior in photoconductor based on dye-sensitized solar cell

    NASA Astrophysics Data System (ADS)

    Wang, X. Q.; Cai, C. B.; Wang, Y. F.; Zhou, W. Q.; Lu, Y. M.; Liu, Z. Y.; Hu, L. H.; Dai, S. Y.

    2009-07-01

    A photogated transistor is established based on the dye-sensitized solar cell using nanocrystalline TiO2 films. Voltage-current curves are characterized with three types of transport behaviors: linear increase, saturated plateau, and breakdownlike increase, which are actually of the typical performances for a phototransistor. Moreover, an asymmetric behavior is observed in the voltage-current loops, which is believed to be due to the difference in the effective photoconducting areas rather than the cross-section areas. The photovoltaic voltage between the common counter electrode and drain (VCE-D) is examined as well during the loop measurements, clarifying that the predominant dark process in source and the predominant photovoltaic process in drain are series connected, modifying the electric potential levels, and thus resulting in the characteristic phototransistor behaviors.

  16. Influence of Ancillary Ligands in Dye-Sensitized Solar Cells.

    PubMed

    Pashaei, Babak; Shahroosvand, Hashem; Graetzel, Michael; Nazeeruddin, Mohammad Khaja

    2016-08-24

    Dye-sensitized solar cells (DSSCs) have motivated many researchers to develop various sensitizers with tailored properties involving anchoring and ancillary ligands. Ancillary ligands carry favorable light-harvesting abilities and are therefore crucial in determining the overall power conversion efficiencies. The use of ancillary ligands having aliphatic chains and/or π-extended aromatic units decreases charge recombination and permits the collection of a large fraction of sunlight. This review aims to provide insight into the relationship between ancillary ligand structure and DSSC properties, which can further guide the function-oriented design and synthesis of different sensitizers for DSSCs. This review outlines how the new and rapidly expanding class of chelating ancillary ligands bearing 2,2'-bipyridyl, 1,10-phenanthroline, carbene, dipyridylamine, pyridyl-benzimidazole, pyridyl-azolate, and other aromatic ligands provides a conduit for potentially enhancing the performance and stability of DSSCs. Finally, these classes of Ru polypyridyl complexes have gained increasing interest for feasible large-scale commercialization of DSSCs due to their more favorable light-harvesting abilities and long-term thermal and chemical stabilities compared with other conventional sensitizers. Therefore, the main idea is to inspire readers to explore new avenues in the design of new sensitizers for DSSCs based on different ancillary ligands. PMID:27479482

  17. Peptide-templating dye-sensitized solar cells.

    PubMed

    Han, Tae Hee; Moon, Hyoung-Seok; Hwang, Jin Ok; Seok, Sang Il; Im, Sang Hyuk; Kim, Sang Ouk

    2010-05-01

    A hollow TiO(2) nanoribbon network electrode for dye-sensitized solar cells (DSSC) was fabricated by a biotemplating process combining peptide self-assembly and atomic layer deposition (ALD). An aromatic peptide of diphenylalanine was assembled into a three-dimensional network consisting of highly entangled nanoribbons. A thin TiO(2) layer was deposited at the surface of the peptide template via the ALD process. After the pyrolysis of the peptide template, a highly entangled nanotubular TiO(2) framework was successfully prepared. Evolution of the crystal phase and crystallite size of the TiO(2) nanostructure was exploited by controlling the calcination temperature. Finally, the hollow TiO(2) nanoribbon network electrode was integrated into DSSC devices and their photochemical performances were investigated. Hollow TiO(2) nanoribbon-based DSSCs exhibited a power conversion efficiency of 3.8%, which is comparable to the conventional TiO(2) nanoparticle-based DSSCs (3.5%). Our approach offers a novel pathway for DSSCs consisting of TiO(2) electrodes via biotemplating. PMID:20378945

  18. Peptide-templating dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Han, Tae Hee; Moon, Hyoung-Seok; Hwang, Jin Ok; Seok, Sang Il; Im, Sang Hyuk; Ouk Kim, Sang

    2010-05-01

    A hollow TiO2 nanoribbon network electrode for dye-sensitized solar cells (DSSC) was fabricated by a biotemplating process combining peptide self-assembly and atomic layer deposition (ALD). An aromatic peptide of diphenylalanine was assembled into a three-dimensional network consisting of highly entangled nanoribbons. A thin TiO2 layer was deposited at the surface of the peptide template via the ALD process. After the pyrolysis of the peptide template, a highly entangled nanotubular TiO2 framework was successfully prepared. Evolution of the crystal phase and crystallite size of the TiO2 nanostructure was exploited by controlling the calcination temperature. Finally, the hollow TiO2 nanoribbon network electrode was integrated into DSSC devices and their photochemical performances were investigated. Hollow TiO2 nanoribbon-based DSSCs exhibited a power conversion efficiency of 3.8%, which is comparable to the conventional TiO2 nanoparticle-based DSSCs (3.5%). Our approach offers a novel pathway for DSSCs consisting of TiO2 electrodes via biotemplating.

  19. Metal-Free Sensitizers for Dye-Sensitized Solar Cells.

    PubMed

    Chaurasia, Sumit; Lin, Jiann T

    2016-06-01

    This review focuses on our work on metal-free sensitizers for dye-sensitized solar cells (DSSCs). Sensitizers based on D-A'-π-A architecture (D is a donor, A is an acceptor, A' is an electron-deficient entity) exhibit better light harvesting than D-π-A-type sensitizers. However, appropriate molecular design is needed to avoid excessive aggregation of negative charge at the electron-deficient entity upon photoexcitation. Rigidified aromatics, including aromatic segments comprising fused electron-excessive and -deficient units in the spacer, allow effective electronic communication, and good photoinduced charge transfer leads to excellent cell performance. Sensitizers with two anchors/acceptors, D(-π-A)2 , can more efficiently harvest light, inject electrons, and suppress dark current compared with congeners with a single anchor. Appropriate incorporation of heteroaromatic units in the spacer is beneficial to DSSC performance. High-performance, aqueous-based DSSCs can be achieved with a dual redox couple comprising imidazolium iodide and 2,2,6,6-tetramethylpiperidin-N-oxyl, and/or using dyes of improved wettability through the incorporation of a triethylene oxide methyl ether chain. PMID:27114164

  20. The application of electrospun titania nanofibers in dye-sensitized solar cells.

    PubMed

    Krysova, Hana; Zukal, Arnost; Trckova-Barakova, Jana; Chandiran, Aravind Kumar; Nazeeruddin, Mohammad Khaja; Grätzel, Michael; Kavan, Ladislav

    2013-01-01

    Titania nanofibers were fabricated using the industrial Nanospider(TM) technology. The preparative protocol was optimized by screening various precursor materials to get pure anatase nanofibers. Composite films were prepared by mixing a commercial paste of nanocrystalline anatase particles with the electrospun nanofibers, which were shortened by milling. The composite films were sensitized by Ru-bipyridine dye (coded C106) and the solar conversion efficiency was tested in a dye-sensitized solar cell filled with iodide-based electrolyte solution (coded Z960). The solar conversion efficiency of a solar cell with the optimized composite electrode (η = 7.53% at AM 1.5 irradiation) outperforms that of a solar cell with pure nanoparticle film (η = 5.44%). Still larger improvement was found for lower light intensities. At 10% sun illumination, the best composite electrode showed η = 7.04%, referenced to that of pure nanoparticle film (η = 4.69%). There are non-monotonic relations between the film's surface area, dye sorption capacity and solar performance of nanofiber-containing composite films, but the beneficial effect of the nanofiber morphology for enhancement of the solar efficiency has been demonstrated. PMID:23574954

  1. Efficient Cosensitization Strategy for Dye-Sensitized Solar Cells

    NASA Astrophysics Data System (ADS)

    Colonna, Daniele; Capogna, Vincenzo; Lembo, Angelo; Brown, Thomas M.; Reale, Andrea; Di Carlo, Aldo

    2012-02-01

    The challenge of increasing the photocurrent of a dye solar cell device by acting on the spectral response is approached herein. Cosensitization of nanocrystalline titania photoanodes by using two complementary dyes is investigated considering the dyeing time as an additional parameter for the optimization of the cosensitization process. We find that the characteristics of the cosensitized cell can outperform those of the cells made with each single dye. This effect is related to the reduction of the molecular stacking of one of the dyes, which quenches electron transfer to TiO2. Cosensitization results are also related to the cell transparency.

  2. To probe the equivalence and opulence of nanocrystal and nanotube based dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Jyoti, Divya; Mohan, Devendra

    2016-05-01

    Dye-Sensitized solar cells based on TiO2 nanocrystal and TiO2 nanotubes have been fabricated by a simple sol-gel hydrothermal process and their performances have been compared. Current density and voltage (JV) characteristics and incident photon to current conversion efficiency (IPCE) plots have been set as criterion to check which one is better as a photoanode candidate in dye-sensitized solar cell. It has been observed that although open circuit voltage values for both type of cells do not differ much still, nanotube based dye-sensitized solar cells are more successful having an efficiency value of 7.28%.

  3. Carbon coated stainless steel as counter electrode for dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Prakash, Shejale Kiran; Sharma, Rakesh K.; Roy, Mahesh S.; Kumar, Mahesh

    2014-10-01

    A new type of counter electrode for dye sensitized solar cells has been fabricated using a stainless steel sheet as substrate and graphite, graphene and multiwall carbon nanotubes as the catalytic material which applied by screen printing technique. The sheet resistances of the substrates and there influence on the dye sensitized solar cells has been studied. The fabricated counter electrodes i.e. SS-graphite, SS-graphene SS-MWCNT and SS-platinum were tested for their photovoltaic response in the form of dye sensitized solar cells.

  4. Titania nanobundle networks as dye-sensitized solar cell photoanodes

    NASA Astrophysics Data System (ADS)

    Dong, Cunku; Xiang, Wanchun; Huang, Fuzhi; Fu, Dongchuan; Huang, Wenchao; Bach, Udo; Cheng, Yi-Bing; Li, Xin; Spiccia, Leone

    2014-03-01

    Quasi-one-dimensional (1D) titania nanobundles were synthesized via a hydrothermal method and used to print random network nanostructured films. These films are shown to be ideally suited for application as photoanodes in dye-sensitized solar cells (DSCs) as they have a higher porosity compared to the traditional 1D nanostructured TiO2 materials. Devices constructed using the N719 dye and iodide/triiodide as the redox mediator in the electrolyte yielded energy conversion efficiencies (η = 6.1 +/- 0.2%), which were marginally lower than for devices made with the commonly used P25 titania films (η = 6.3 +/- 0.1%) under one sun simulated solar radiation. Application of an electrolyte based on the [Co(bpy)3]2+/3+ redox couple and the MK2 organic sensitizer resulted in higher efficiencies (η = 7.70 +/- 0.1%) than for the P25 devices (η = 6.3 +/- 0.3%). Each performance parameter (short circuit current density, open circuit voltage and fill factor) was higher for the TiO2 nanobundle devices than those for the P25-based devices. The results of electrochemical impedance spectroscopy (EIS), intensity-modulated photovoltage spectroscopy (IMVS), and dye-loading measurements indicated that the better performance of TiO2 nanobundle devices with cobalt electrolytes correlates with higher porosity, relatively fast electron transport and more efficient suppression of electron recombination. A faster rate of diffusion of the cobalt complexes through the highly porous TiO2 nanobundle network is proposed to contribute to the enhanced device efficiency.Quasi-one-dimensional (1D) titania nanobundles were synthesized via a hydrothermal method and used to print random network nanostructured films. These films are shown to be ideally suited for application as photoanodes in dye-sensitized solar cells (DSCs) as they have a higher porosity compared to the traditional 1D nanostructured TiO2 materials. Devices constructed using the N719 dye and iodide/triiodide as the redox mediator in

  5. Fundamental studies of nanoarchitectured dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Yang, Zhenzhen

    2011-12-01

    Dye-sensitized solar cells (DSSCs) are a promising candidate for next-generation photovoltaic panels due to their low cost, easy fabrication processes and relatively high efficiency. Despite the considerable effort on the advancement of DSSCs, the efficiency of DSSCs has been stalled for nearly two decades due to the complex interplay among various DSSC parameters. Particularly, in a conventional DSSC, a thicker semiconductor photovoltaic (PV) layer, i.e., a dye-sensitized TiO2 nanoparticle layer, is required to accommodate more light-induced charge separation centers to enhance light harvesting efficiency. However, a thicker PV layer concurrently increases the charge transport distance in the PV layer; so the system suffers from more charge recombination, leading to significant deterioration in charge collection efficiency. The conflicting demands on the thickness of PV layer by these two critical elementary photoelectrochemical processes becomes a fundamental limitation for further advancement in DSSCs and limits the choice of redox mediators and electrode materials in DSSCs. Hence, the focus of this dissertation research work is to systematically explore a transformative way to fundamentally resolve the conflicting interplay between light harvesting and charge transport. First, our strategy is to allocate part of the roughness factor to the collecting anode instead of imparting all the roughness factors onto the semiconductor PV layer attached to the anode. As a proof of concept, we first synthesized and characterized a microscopically rough Zn collecting anode, on which ZnO nanotips are grown. For the same surface roughness factor, the length of the ZnO nanotips supported on such a rough Zn anode can be much shorter than that of the ZnO nanowires supported on a planar anode. Our Zn-microtip|ZnO-nanotip DSSCs exhibit enhanced fill factor, Voc and Jsc. The investigation of kinetics indicates that the electron collection time is much faster than the electron

  6. Charge separation in solid-state dye-sensitized heterojunction solar cells

    SciTech Connect

    Bach, U.; Tachibana, Yasuhiro; Moser, J.E.; Haque, S.A.; Durrant, J.R.; Graetzel, M.; Klug, D.R.

    1999-08-18

    Dye-sensitized nanocrystalline solar cells are presently under intensive investigation, as they offer an attractive alternative to conventional p--n junction devices. Solid-state versions have been described where the electrolyte present in the pores of the malodorous oxide film is replaced by a large band gap p-type semiconductor. In this way, a solid-state heterojunction of very large contact area is formed. Light is absorbed by the dye that is located at the interface. Upon excitation, the dye injects electrons into the conduction band of the oxide and is regenerated by hole injection into the p-type conductor. High incident photon-to-electric current conversion efficiencies have been achieved recently with a cell consisting of a dye-derivatized mesoporous TiO{sub 2} film contacted by a new organic hole conductor. The great advantage of such systems with regard to conventional p--n junctions is that only majority carriers are involved in the photoelectric conversion process. Moreover, these are generated by the dye precisely at the site of the junction where the electric field is maximal, enhancing charge separation. Photoelectric conversion by conventional solar cells involves minority carriers whose lifetime is restricted due to recombination. As they are generated throughout the semiconductor and away from the junction, expensive high-purity materials are required in order to maintain the minority carrier diffusion length at a level where current losses are avoided. While the dynamics of photoinduced redo processes in photoelectrochemical systems have been studied in great detail, little is known about the electron-transfer dynamics in solid-state sensitized junctions. Here the authors report for the first time on the direct observation of photoinduced, interfacial charge separation across a dye-sensitized solid-state heterojunction by means of picosecond transient absorption laser spectroscopy.

  7. Photo-electrochemical studies of chemically deposited nanocrystalline meso-porous n-type TiO2 thin films for dye-sensitized solar cell (DSSC) using simple synthesized azo dye

    NASA Astrophysics Data System (ADS)

    Ezema, C. G.; Nwanya, A. C.; Ezema, B. E.; Patil, B. H.; Bulakhe, R. N.; Ukoha, P. O.; Lokhande, C. D.; Maaza, Malik; Ezema, Fabian I.

    2016-04-01

    Nanocrystalline titanium dioxide (TiO2) thin films were deposited by successive ionic layer adsorption and reaction method onto fluorine doped tin oxide coated glass substrate at room temperature (300 K). Titanium trichloride and sodium hydroxide were used as cationic and anionic sources, respectively. The as-deposited and annealed films were characterized for structural, morphological, optical, electrical and wettability properties. The photoelectrochemical study of TiO2 sensitized with a laboratory synthesized organic dye (azo) was evaluated in the polyiodide electrolyte at 40 mW cm-2 light illumination intensity. The photovoltaic characteristics show a fill factor of 0.24 and solar conversion efficiency value of 0.032 % for a TiO2 thickness of 0.96 µm as compared to efficiency of 0.014 % for rose Bengal of the same thickness.

  8. Dye Sensitized Tandem Photovoltaic Cells

    SciTech Connect

    Barber, Greg D.

    2009-12-21

    This work provided a new way to look at photoelectrochemical cells and their performance. Although thought of as low efficiency, a the internal efficiency of a 9% global efficiency dye sensitized solar cell is approximately equal to an 18% efficient silicon cell when each is compared to their useful spectral range. Other work undertaken with this contract also reported the first growth oriented titania and perovskite columns on a transparent conducting oxide. Other work has shown than significant performance enhancement in the performance of dye sensitized solar cells can be obtained through the use of coupling inverse opal photonic crystals to the nanocrystalline dye sensitized solar cell. Lastly, a quick efficient method was developed to bond titanium foils to transparent conducting oxide substrates for anodization.

  9. The electronic structure engineering of organic dye sensitizers for solar cells: The case of JK derivatives.

    PubMed

    Zhang, Cai-Rong; Ma, Jin-Gang; Zhe, Jian-Wu; Jin, Neng-Zhi; Shen, Yu-Lin; Wu, You-Zhi; Chen, Yu-Hong; Liu, Zi-Jiang; Chen, Hong-Shan

    2015-11-01

    The design and development of novel dye sensitizers are effective method to improve the performance of dye-sensitized solar cells (DSSCs) because dye sensitizers have significant influence on photo-to-current conversion efficiency. In the procedure of dye sensitizer design, it is very important to understand how to tune their electronic structures and related properties through the substitution of electronic donors, acceptors, and conjugated bridges in dye sensitizers. Here, the electronic structures and excited-state properties of organic JK dye sensitizers are calculated by using density functional theory (DFT) and time dependent DFT methods. Based upon the calculated results, we investigated the role of different electronic donors, acceptors, and π-conjugated bridges in the modification of electronic structures, absorption properties, as well as the free energy variations for electron injection and dye regeneration. In terms of the analysis of transition configurations and molecular orbitals, the effective chromophores which are favorable for electron injection in DSSCs are addressed. Meanwhile, considering the absorption spectra and free energy variation, the promising electronic donors, π-conjugated bridges, and acceptors are presented to design dye sensitizers. PMID:26116996

  10. Molecular design rule of phthalocyanine dyes for highly efficient near-IR performance in dye-sensitized solar cells.

    PubMed

    Kimura, Mutsumi; Nomoto, Hirotaka; Suzuki, Hiroyuki; Ikeuchi, Takuro; Matsuzaki, Hiroyuki; Murakami, Takuro N; Furube, Akihiko; Masaki, Naruhiko; Griffith, Matthew J; Mori, Shogo

    2013-06-01

    A series of zinc-phthalocyanine sensitizers (PcS16-18) with different adsorption sites have been designed and synthesized in order to investigate the dependence of adsorption-site structures on the solar-cell performances in zinc-phthalocyanine based dye-sensitized solar cells. The change of adsorption site affected the electron injection efficiency from the photoexcited dye into the nanocrystalline TiO2 semiconductor, as monitored by picosecond time-resolved fluorescence spectroscopy. The zinc-phthalocyanine sensitizer PcS18, possessing one carboxylic acid directly attached to the ZnPc ring and six 2,6-diisopropylphenoxy units, showed a record power conversion efficiency value of 5.9 % when used as a light-harvesting dye on a TiO2 electrode under one simulated solar condition. PMID:23576330

  11. Synthesis and characterization of Allium cepa L. as photosensitizer of dye-sensitized solar cell

    NASA Astrophysics Data System (ADS)

    Sutikno, Afrian, Noverdi; Supriadi, Putra, Ngurah Made Dharma

    2016-04-01

    The synthesis and characterization of Allium cepa L. used as natural pigment for natural dye sensitizer of solar cell has successfully done and anthocyanin is extracted. Anthocynin is color pigment of plant which has characteristic absorption spectrum of photon and excites electrons up to pigment molecules. As the anthocyanin absorbed light increases the excited electrons increase as well. The generated current also increases and it leads to the efficiency increase. The energy conversion efficiency of the cells sensitized with dye of Allium cepa L. was 3,045 x 10-4%. A simple technique was taken to fabricate dye sensitizer solar cell is spincoating.

  12. All-solid-state dye-sensitized solar cells with high efficiency.

    PubMed

    Chung, In; Lee, Byunghong; He, Jiaqing; Chang, Robert P H; Kanatzidis, Mercouri G

    2012-05-24

    Dye-sensitized solar cells based on titanium dioxide (TiO(2)) are promising low-cost alternatives to conventional solid-state photovoltaic devices based on materials such as Si, CdTe and CuIn(1-x)Ga(x)Se(2) (refs 1, 2). Despite offering relatively high conversion efficiencies for solar energy, typical dye-sensitized solar cells suffer from durability problems that result from their use of organic liquid electrolytes containing the iodide/tri-iodide redox couple, which causes serious problems such as electrode corrosion and electrolyte leakage. Replacements for iodine-based liquid electrolytes have been extensively studied, but the efficiencies of the resulting devices remain low. Here we show that the solution-processable p-type direct bandgap semiconductor CsSnI(3) can be used for hole conduction in lieu of a liquid electrolyte. The resulting solid-state dye-sensitized solar cells consist of CsSnI(2.95)F(0.05) doped with SnF(2), nanoporous TiO(2) and the dye N719, and show conversion efficiencies of up to 10.2 per cent (8.51 per cent with a mask). With a bandgap of 1.3 electronvolts, CsSnI(3) enhances visible light absorption on the red side of the spectrum to outperform the typical dye-sensitized solar cells in this spectral region. PMID:22622574

  13. Solar energy conversion at dye sensitized nanostructured electrodes fabricated by sol-gel processing: Final report

    SciTech Connect

    Searson, P C; Meyer, G J

    1998-07-01

    The significant achievements accomplished in this program include: (1) the first demonstration of osmium polypyridyl compounds as sensitizers; (2) the first demonstration of donor-acceptor compounds as sensitizers; (3) the first utilization of alternative acac based sensitizer-semiconductor linkages; (4) the first demonstration of remote interfacial electron transfer; (5) the first application of bimetallic compounds as sensitizers; (6) the first correlation of the interfacial charge recombination rate constant with the open circuit photovoltage in sensitized materials; (7) the first demonstration of a solid state dye sensitized TiO{sub 2} cell; (8) an alternative band edge unpinning model for the nanocrystalline TiO{sub 2}/electrolyte interface at negative applied potentials; and (9) the first self-consistent model of electron transport in dye sensitized TiO{sub 2} films. In the following sections the authors summarize some of the results from this program and highlight the key findings.

  14. Triphenylamine-based indoline derivatives for dye-sensitized solar cells: a density functional theory investigation.

    PubMed

    Ren, Xue-Feng; Kang, Guo-Jun; He, Qiong-Qiong

    2016-01-01

    A new series of triphenylamine-based indoline dye sensitizers were molecularly designed and investigated for their potential use in dye-sensitized solar cells (DSSCs). Theoretical calculations revealed that modifying donor part of D149 by triphenylamine significantly altered the electronic structures, MO energies, and intramolecular charge transfer (ICT) absorption band. Key parameters associated with the light-harvesting efficiency at a given wavelength LHE(λ), the driving force ΔG inject, and the open-circuit photovoltage V oc were characterized. More importantly, these designed (dimeric) dye sensitizers were found to have similar broad absorption spectra to their corresponding monomers, indicating that modifying the donor part with triphenylamine may stop unfavorable dye aggregation. Further analyses of the dye-(TiO2)9 cluster interaction confirmed that there was strong electronic coupling at the interface. These results are expected to provide useful guidance in the molecular design of new highly efficient metal-free organic dyes. PMID:26659403

  15. On the early development of organic dyes for dye-sensitized solar cells.

    PubMed

    Kloo, Lars

    2013-07-28

    This viewpoint describes the background of the development of organic dyes for dye-sensitized solar cells, the impact of the 2006 ChemComm paper by Sun, Hagfeldt and co-workers regarding the D5 D-π-A-family of dyes, some recent developments and possible future challenges to meet. PMID:23775237

  16. A strategy to design novel structure photochromic sensitizers for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Wu, Wenjun; Wang, Jiaxing; Zheng, Zhiwei; Hu, Yue; Jin, Jiayu; Zhang, Qiong; Hua, Jianli

    2015-02-01

    Two sensitizers with novel structure were designed and synthetized by introducing photochromic bisthienylethene (BTE) group into the conjugated system. Thanks to the photochromic effect the sensitizers have under ultraviolet and visible light, the conjugated bridge can be restructured and the resulting two photoisomers showed different behaviors in photovoltaic devices. This opens up a new research way for the dye-sensitized solar cells (DSSCs).

  17. Cylindrical dye-sensitized solar cells with high efficiency and stability over time and incident angle.

    PubMed

    Tang, Qunwei; Zhang, Lei; He, Benlin; Yu, Liangmin; Yang, Peizhi

    2016-02-28

    We present here the realization of cylindrical dye-sensitized solar cells composed of Ti wire supported TiO2 nanotube anodes and transparent metal selenide counter electrodes. The optimized device yields a high efficiency of 6.63%, good stability over time, and identical efficiency output at arbitrary incident angles. PMID:26839927

  18. Dye-sensitized solar cells based on multichromophoric supramolecular light-harvesting materials.

    PubMed

    Panda, Dillip K; Goodson, Flynt S; Ray, Shuvasree; Saha, Sourav

    2014-05-25

    Multichromophoric dye-sensitized solar cells (DSSCs) comprised of a supramolecular zinc-phthalocyanineperyleneimide (ZnPc···PMI) dyad convert light to electrical energy with much higher power conversion efficiency (PCE = 2.3%) and incident-photon-to-current-efficiency (IPCE = ca. 40%) than the devices made of individual dyes. PMID:24409457

  19. See-through dye-sensitized solar cells: photonic reflectors for tandem and building integrated photovoltaics.

    PubMed

    Heiniger, Leo-Philipp; O'Brien, Paul G; Soheilnia, Navid; Yang, Yang; Kherani, Nazir P; Grätzel, Michael; Ozin, Geoffrey A; Tétreault, Nicolas

    2013-10-25

    See-through dye-sensitized solar cells with 1D photonic crystal Bragg reflector photoanodes show an increase in peak external quantum efficiency of 47% while still maintaining high fill factors, resulting in an almost 40% increase in power conversion efficiency. These photoanodes are ideally suited for tandem and building integrated photovoltaics. PMID:23966106

  20. A low recombination rate indolizine sensitizer for dye-sensitized solar cells.

    PubMed

    Huckaba, Aron J; Yella, Aswani; Brogdon, Phillip; Scott Murphy, J; Nazeeruddin, Mohammad Khaja; Grätzel, Michael; Delcamp, Jared H

    2016-06-28

    A sensitizer incorporating a heavily alkylated surface blocking indolizine donor exhibits excellent light absorption and diminished recombination rates in dye-sensitized solar cells (DSCs). DSC device efficiencies (up to 8%) using either I(-)/I3(-) or Co(bpy)3(2+/3+) redox shuttles were obtained, which compare favourably to the known excellent surface coverage co-sensitization dye, . PMID:27301449

  1. Bi-functional ion exchangers for enhanced performance of dye-sensitized solar cells.

    PubMed

    Kong, Eui-Hyun; Chang, Yong-June; Lim, Jongchul; Kim, Back-Hyun; Lee, Jung-Hoon; Kwon, Do-Kyun; Park, Taiho; Jang, Hyun Myung

    2013-07-28

    Ion exchange using aerosol OT (AOT) offers dye adsorption twice as fast as known methods. Moreover, it suppresses the dye-agglomeration that may cause insufficient dye-coverage on the photoelectrode surface. Consequently, its dual function of fast dye-loading and higher dye-coverage significantly improves the power conversion efficiency of dye-sensitized solar cells. PMID:23775416

  2. Eugenic metal-free sensitizers with double anchors for high performance dye-sensitized solar cells.

    PubMed

    Hung, Wei-I; Liao, You-Ya; Lee, Ting-Hui; Ting, Yu-Chien; Ni, Jen-Shyang; Kao, Wei-Siang; Lin, Jiann T; Wei, Tzu-Chien; Yen, Yung-Sheng

    2015-02-01

    A series of new phenothiazine-based dyes (HL5-HL7) with double acceptors/anchors have been synthesized and used as the sensitizers for highly efficient dye-sensitized solar cells (DSSCs). Among them, the HL7-based cell exhibits the best efficiency of 8.32% exceeding the N719-based cell (7.35%) by ∼13%. PMID:25555237

  3. Natural dye sensitized TiO2 nanorods assembly of broccoli shape based solar cells.

    PubMed

    Yuvapragasam, Akila; Muthukumarasamy, N; Agilan, S; Velauthapillai, Dhayalan; Senthil, T S; Sundaram, Senthilarasu

    2015-07-01

    TiO2 nanorods based thin films with rutile phase have been synthesized using template free low temperature hydrothermal method. The scanning electron microscope images showed that the prepared TiO2 samples were made of TiO2 nanorods and the nanorods had arranged by itself to form a broccoli like shape. The X-ray diffraction studies revealed that the prepared TiO2 samples exhibit rutile phase. The grown TiO2 nanorods had been sensitized using the flowers of Sesbania (S) grandiflora, leaves of Camellia (C) sinensis and roots of Rubia (R) tinctorum. Dye sensitized solar cells had been fabricated using the natural dye sensitized TiO2 nanorods based thin film photoelectrode and the open circuit voltage and short circuit current density were found to lie in the range of 0.45-0.6 V and 5.6-6.4 mA/cm(2) respectively. The photovoltaic performance of all the fabricated natural dye sensitized TiO2 solar cells indicate that natural dyes have the potential to be used as effective sensitizer in dye sensitized solar cells. PMID:25974906

  4. Highly stable tandem solar cell monolithically integrating dye-sensitized and CIGS solar cells

    PubMed Central

    Chae, Sang Youn; Park, Se Jin; Joo, Oh-Shim; Jun, Yongseok; Min, Byoung Koun; Hwang, Yun Jeong

    2016-01-01

    A highly stable monolithic tandem solar cell was developed by combining the heterogeneous photovoltaic technologies of dye-sensitized solar cell (DSSC) and solution-processed CuInxGa1-xSeyS1-y (CIGS) thin film solar cells. The durability of the tandem cell was dramatically enhanced by replacing the redox couple from to [Co(bpy)3]2+ /[Co(bpy)3]3+), accompanied by a well-matched counter electrode (PEDOT:PSS) and sensitizer (Y123). A 1000 h durability test of the DSSC/CIGS tandem solar cell in ambient conditions resulted in only a 5% decrease in solar cell efficiency. Based on electrochemical impedance spectroscopy and photoelectrochemical cell measurement, the enhanced stability of the tandem cell is attributed to minimal corrosion by the cobalt-based polypyridine complex redox couple. PMID:27489138

  5. Highly stable tandem solar cell monolithically integrating dye-sensitized and CIGS solar cells

    NASA Astrophysics Data System (ADS)

    Chae, Sang Youn; Park, Se Jin; Joo, Oh-Shim; Jun, Yongseok; Min, Byoung Koun; Hwang, Yun Jeong

    2016-08-01

    A highly stable monolithic tandem solar cell was developed by combining the heterogeneous photovoltaic technologies of dye-sensitized solar cell (DSSC) and solution-processed CuInxGa1-xSeyS1-y (CIGS) thin film solar cells. The durability of the tandem cell was dramatically enhanced by replacing the redox couple from to [Co(bpy)3]2+ /[Co(bpy)3]3+), accompanied by a well-matched counter electrode (PEDOT:PSS) and sensitizer (Y123). A 1000 h durability test of the DSSC/CIGS tandem solar cell in ambient conditions resulted in only a 5% decrease in solar cell efficiency. Based on electrochemical impedance spectroscopy and photoelectrochemical cell measurement, the enhanced stability of the tandem cell is attributed to minimal corrosion by the cobalt-based polypyridine complex redox couple.

  6. Dye-Sensitized Solar Cells: The Future of Using Earth-Abundant Elements in Counter Electrodes for Dye-Sensitized Solar Cells (Adv. Mater. 20/2016).

    PubMed

    Briscoe, Joe; Dunn, Steve

    2016-05-01

    Sustainability is an important concept generating traction in the research community. To be really sustainable the full life cycle of a product needs to be carefully considered. A key aspect of this is using elements that are either readily recycled or accessible in the Earth's biosphere. Jigsawing these materials together in compounds to address our future energy needs represents a great opportunity for the current generation of researchers. On page 3802, S. Dunn and J. Briscoe summarize the performance of a selection of alternative materials to replace platinum in the counter electrodes of dye-sensitized solar cells. PMID:27197641

  7. Effects of cell area on the performance of dye sensitized solar cell

    SciTech Connect

    Khatani, Mehboob E-mail: noranimuti-mohamed@petronas.com.my E-mail: azclement@yahoo.com Mohamed, Norani Muti E-mail: noranimuti-mohamed@petronas.com.my E-mail: azclement@yahoo.com Hamid, Nor Hisham E-mail: noranimuti-mohamed@petronas.com.my E-mail: azclement@yahoo.com Sahmer, Ahmad Zahrin E-mail: noranimuti-mohamed@petronas.com.my E-mail: azclement@yahoo.com Samsudin, Adel E-mail: noranimuti-mohamed@petronas.com.my E-mail: azclement@yahoo.com

    2014-10-24

    Dye sensitized solar cells (DSCs) have significant advantage over the current silicon cells by having low manufacturing cost and potentially high conversion efficiency. Therefore, DSCs are expected to be used as the next generation solar cell device that covers wide range of new applications. In order to achieve highly efficient DSCs for practical application, study on the effect of increasing the cell’s area on the performance of dye sensitized solar need to be carried out. Three different DSC cell areas namely, 1, 12.96 and 93.5 cm{sup 2} respectively were fabricated and analyzed through solar simulator and electrochemical impedance spectroscopy (EIS). From the analysis of electrochemical impedance spectroscopy (EIS), it was observed that the cell’s electron lifetime was influenced significantly by the cell’s area. Although the collection efficiency of all cells recorded to be approximately 100% but higher recombination rate with increased cell area reduced the performance of the cell.

  8. Light trapping and plasmonic enhancement in silicon, dye-sensitized and titania solar cells

    NASA Astrophysics Data System (ADS)

    Nhung Tran, Hong; Hieu Nguyen, Van; Nguyen, Bich Ha; Vu, Dinh Lam

    2016-03-01

    The efficiency of a solar cell depends on both the quality of its semiconductor active layer, as well as on the presence of other dielectric and metallic structural components which improve light trapping and exploit plasmonic enhancement. The purpose of this work is to review the results of recent research on light trapping and plasmonic enhancement in three types of solar cells: thin-film silicon solar cells, dye-sensitized solar cells and solid-state titania solar cells. The results of a study on modeling and the design of light trapping components in solar cells are also presented.

  9. Flexible Dye-Sensitized Solar Cell based on Vertical ZnO Nanowire Arrays

    SciTech Connect

    Chu, Sheng; Li, Dongdong; Chang, Pai-Chun; Lu, Jia Grace

    2010-09-26

    Flexible dye-sensitized solar cells are fabricated using vertically aligned ZnO nanowire arrays that are transferred onto ITO-coated poly(ethylene terephthalate) substrates using a simple peel-off process. The solar cells demonstrate an energy conversion efficiency of 0.44% with good bending tolerance. This technique paves a new route for building large-scale cost-effective flexible photovoltaic and optoelectronic devices.

  10. Effects of pH of Dyes on Characteristics of Dye-Sensitized Solar Cells

    NASA Astrophysics Data System (ADS)

    Furukawa, Shoji; Iino, Hiroshi; Kukita, Koudai; Kaminosono, Kaoru

    Dye-sensitized solar cells were fabricated using natural dyes and synthesized dyes in which rear metal was not contained. Effects of pH of dyes on the characteristics of the dye-sensitized solar cells were also examined. As a result, it was found that the conversion efficiency of the dye-sensitized solar cell fabricated using red-cabbage dye with a pH of 2.5 was 0.10 point larger than that of the solar cell fabricated using red-cabbage dye with a pH of 4.0. It was also found that the conversion efficiency of the solar cell fabricated using red-perilla dye with a pH of 3.1 was 0.10 point larger than that of the solar cell fabricated using red-perilla dye with a pH of 5.8. The results are discussed on the bases of the molecular structure of mainly contained dye and the optical absorption spectra.

  11. The enhancement of photovoltaic parameters in dye-sensitized solar cells of nano-crystalline SnO2 by incorporating with large SrTiO3 particles.

    PubMed

    Aponsu, G M L P; Wijayarathna, T R C K; Perera, I K; Perera, V P S; Siriwardhana, A C P K

    2013-05-15

    In this paper, the performance of nano-porous electrodes made of a composite material of SrTiO3 and SnO2 are compared with those made of bare SnO2. When these particular devices are analyzed in a comparative mode the results confirmed the enhancement of photovoltaic parameters in the former device. The performance of respective cells were examined by several methods including I-V characteristic measurements, photocurrent action spectra, dark I-V measurements, Mott-Schottky measurements and X-ray diffraction measurements. Even though such improvements in this particular cell could be explicated by the formation of a potential energy barrier of SrTiO3 particles of comparably large width at the SrTiO3/SnO2 interface, the passivation of voids in the SnO2 film by SrTiO3 particles to a certain extent could not be totally ruled out. Besides, high energetic electrons injected by dye molecules move more credibly through mini-bands formed in the chain of nano-crystalline SnO2 particles to the back contact. The blocking of the recombination path and the shifting up of the uppermost electron occupied level of SnO2 accompanying the conduction band edge in the SrTiO3/SnO2 composite film, may have lead to the observed enhancement of the fill factor and photovoltage, respectively. PMID:23501715

  12. Electrical characterization of dye sensitized nano solar cell using natural pomegranate juice as photosensitizer

    NASA Astrophysics Data System (ADS)

    Adithi, U.; Thomas, Sara; Uma, V.; Pradeep, N.

    2013-02-01

    This paper shows Electrical characterization of Dye Sensitized Solar Cell using natural dye, extracted from the pomegranate as a photo sensitizer and ZnO nanoparticles as semiconductor. The constituents of fabricated dye sensitized solar cell were working electrode, dye, electrolyte and counter electrode. ZnO nanoparticles were synthesized and used as semiconductor in working electrode. Carbon soot was used as counter electrode. The resistance of ZnO film on ITO film was found out. There was an increase in the resistance of the film and film changes from conducting to semiconducting. Photovoltaic parameters of the fabricated cell like Short circuit current, open circuit voltage, Fill factor and Efficiency were found out. This paper shows that usage of natural dyes like pomegranate juice as sensitizer enables faster and simpler production of cheaper and environmental friendly solar cell.

  13. Applications of Metal Oxide Materials in Dye Sensitized Photoelectrosynthesis Cells for Making Solar Fuels: Let the Molecules do the Work

    SciTech Connect

    Alibabaei, Leila; Luo, Hanlin; House, Ralph L.; Hoertz, Paul G.; Lopez, Rene; Meyer, Thomas J.

    2013-01-01

    Solar fuels hold great promise as a permanent, environmentally friendly, long-term renewable energy source, that would be readily available across the globe. In this account, an approach to solar fuels is described based on Dye Sensitized Photoelectrosynthesis Cells (DSPEC) that mimic the configuration used in Dye Sensitized Solar Cells (DSSC), but with the goal of producing oxygen and a high energy solar fuel in the separate compartments of a photoelectrochemical cell rather than a photopotential and photocurrent.

  14. Solar energy conversion by dye-sensitized photovoltaic cells.

    PubMed

    Grätzel, Michael

    2005-10-01

    The quality of human life depends to a large degree on the availability of energy. This is threatened unless renewable energy resources can be developed in the near future. Chemistry is expected to make important contributions to identify environmentally friendly solutions of the energy problem. One attractive strategy discussed in this Forum Article is the development of solar cells that are based on the sensitization of mesoscopic oxide films by dyes or quantum dots. These systems have already reached conversion efficiencies exceeding 11%. The underlying fundamental processes of light harvesting by the sensitizer, heterogeneous electron transfer from the electronically excited chromophore into the conduction band of the semiconductor oxide, and percolative migration of the injected electrons through the mesoporous film to the collector electrode will be described below in detail. A number of research topics will also be discussed, and the examples for the first outdoor application of such solar cells will be provided. PMID:16180840

  15. Influence of polar solvents on photovoltaic performance of Monascusred dye-sensitized solar cell

    NASA Astrophysics Data System (ADS)

    Lee, Jae Wook; Kim, Tae Young; Ko, Hyun Seok; Han, Shin; Lee, Suk-Ho; Park, Kyung Hee

    Dye-sensitized solar cells (DSSCs) were assembled using natural dyes extracted from Monascus red pigment as a sensitizer. In this work, we studied the adsorption characteristics for harvesting sunlight and the electrochemical behavior for electron transfer in Monascus red DSSC using different solvents. The effect of polar aprotic and protic solvents including water, ethanol, and dimethylsulfoxide (DMSO) used in the sensitization process was investigated for the improvement in conversion efficiency of a cell. As for the Monascus red dye-sensitized electrode in DMSO solvent, the solar cell yields a short-circuit current density (Jsc) of 1.23 mA/cm2, a photovoltage (Voc) of 0.75 V, and a fill factor of 0.72, corresponding to an energy conversion efficiency (η) of 0.66%.

  16. Characteristics of nanostructure dye-sensitized solar cells using food dyes

    NASA Astrophysics Data System (ADS)

    Hosseinnezhad, M.; Rouhani, S.

    2016-01-01

    Dye-sensitized solar cells (DSSCs) were prepared using various food dyes. Food dyes are economically superior to organometallic dyes since they are nontoxic and inexpensive. The spectrophotometric evaluation of chosen food dyes in solution and on a TO2 substrate show that the dyes form J-aggregation on the photoelectrode substrate. Oxidation of potential measurements for used food dyes ensured an energetically permissible and thermodynamically favorable charge transfer throughout the continuous cycle of a photo-electric conversion. The performance of dye-sensitized solar cells based on food dyes was studied. The results illustrate that the dye containing carboxylic acid and sulfonic acid as the acceptor group gave the maximum conversion efficiency 4.20%.

  17. Characteristics of nanostructure dye-sensitized solar cells using food dyes

    NASA Astrophysics Data System (ADS)

    Hosseinnezhad, M.; Rouhani, S.

    2016-01-01

    Dye-sensitized solar cells (DSSCs) were prepared using various food dyes. Food dyes are economically superior to organometallic dyes since they are nontoxic and inexpensive. The spectrophotometric evaluation of chosen food dyes in solution and on a TiO2 substrate show that the dyes form J-aggregation on the photoelectrode substrate. Oxidation of potential measurements for used food dyes ensured an energetically permissible and thermodynamically favorable charge transfer throughout the continuous cycle of a photo-electric conversion. The performance of dye-sensitized solar cells based on food dyes was studied. The results illustrate that the dye containing carboxylic acid and sulfonic acid as the acceptor group gave the maximum conversion efficiency 4.20%.

  18. The 2010 millennium technology grand prize: dye-sensitized solar cells.

    PubMed

    Meyer, Gerald J

    2010-08-24

    The 2010 Millennium Technology Grand Prize was awarded to Michael Gratzel for his ground-breaking research that has led to the practical application of dye-sensitized solar cells. Although Gratzel began his research well before nanotechnology had the "buzz" that it does today, the mesoscopic thin films he has developed have paved the way for generations of scientists to exploit the nanoscale for energy conversion. In addition to practical application, his research has led to a deeper understanding of photoinitiated charge-transfer processes at semiconductor interfaces. Here, the key scientific developments that guided early progress in dye-sensitized solar cells are summarized, with emphasis on fundamental advances that have enabled practical application. PMID:20731419

  19. A home-made system for IPCE measurement of standard and dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Palma, Giuseppina; Cozzarini, Luca; Capria, Ennio; Fraleoni-Morgera, Alessandro

    2015-01-01

    A home-made system for incident photon-to-electron conversion efficiency (IPCE) characterization, based on a double-beam UV-Vis spectrophotometer, has been set up. In addition to its low cost (compared to the commercially available apparatuses), the double-beam configuration gives the advantage to measure, autonomously and with no need for supplementary equipment, the lamp power in real time, compensating possible variations of the spectral emission intensity and quality, thus reducing measurement times. To manage the optical and electronic components of the system, a custom software has been developed. Validations carried out on a common silicon-based photodiode and on a dye-sensitized solar cell confirm the possibility to adopt this system for determining the IPCE of solar cells, including dye-sensitized ones.

  20. Carbon nanotube counter electrode for high-efficient fibrous dye-sensitized solar cells

    PubMed Central

    2012-01-01

    High-efficient fibrous dye-sensitized solar cell with carbon nanotube (CNT) thin films as counter electrodes has been reported. The CNT films were fabricated by coating CNT paste or spraying CNT suspension solution on Ti wires. A fluorine tin oxide-coated CNT underlayer was used to improve the adherence of the CNT layer on Ti substrate for sprayed samples. The charge transfer catalytic behavior of fibrous CNT/Ti counter electrodes to the iodide/triiodide redox pair was carefully studied by electrochemical impedance and current-voltage measurement. The catalytic activity can be enhanced by increasing the amount of CNT loading on substrate. Both the efficiencies of fibrous dye-sensitized solar cells using paste coated and sprayed CNT films as counter electrodes are comparative to that using Pt wires, indicating the feasibility of CNT/Ti wires as fibrous counter electrode for superseding Pt wires. PMID:22507398

  1. Printable highly catalytic Pt- and TCO-free counter electrode for dye-sensitized solar cells.

    PubMed

    He, Jian; Lee, Lawrence Tien Lin; Yang, Shihang; Li, Quan; Xiao, Xudong; Chen, Tao

    2014-02-26

    Here we show that a counter electrode based on carbon network supported Cu2ZnSnS4 nanodots on Mo-coated soda-lime glass for dye-sensitized solar cells can outperform the conventional best electrode with Pt nanoparticles on the fluorine-doped SnO2 conducting glass. In the as-developed electrode, all of the elements are of high abundance ratios with low materials cost. The fabrication is scalable because it is conducted by a screen-printing based approach. Therefore, this research lays a solid ground for the large area fabrication of high-performance dye-sensitized solar cell at reduced material cost. PMID:24467193

  2. Improving optical absorptivity of natural dyes for fabrication of efficient dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Hemmatzadeh, Reza; Mohammadi, Ahmad

    2013-11-01

    Efficient and cheap dye-sensitized solar cells (DSSCs) were fabricated using natural dyes from Pastinaca sativa and Beta vulgaris. Natural dyes are environmentally and economically superior to ruthenium-based dyes because they are nontoxic and cheap. However, the conversion efficiency of dye-sensitized solar cells based on natural dyes is low. One way to improve the DSSC performance is to enhance the absorptivity of extracted dyes. We investigated the influence of various factors in the extraction process, such as utilization of different extraction approaches, the acidity of extraction solvent, and different compounds of solvents on the optical absorption spectra. It was found that we could considerably enhance the optical absorptivity of dye and consequently the performance of DSSC by choosing a proper mixture of ethanol and water for extracting solvent and also the acidity of dye solution.

  3. A home-made system for IPCE measurement of standard and dye-sensitized solar cells

    SciTech Connect

    Palma, Giuseppina; Cozzarini, Luca; Capria, Ennio; Fraleoni-Morgera, Alessandro E-mail: afraleoni@units.it

    2015-01-15

    A home-made system for incident photon-to-electron conversion efficiency (IPCE) characterization, based on a double-beam UV-Vis spectrophotometer, has been set up. In addition to its low cost (compared to the commercially available apparatuses), the double-beam configuration gives the advantage to measure, autonomously and with no need for supplementary equipment, the lamp power in real time, compensating possible variations of the spectral emission intensity and quality, thus reducing measurement times. To manage the optical and electronic components of the system, a custom software has been developed. Validations carried out on a common silicon-based photodiode and on a dye-sensitized solar cell confirm the possibility to adopt this system for determining the IPCE of solar cells, including dye-sensitized ones.

  4. Patterned 3-dimensional metal grid electrodes as alternative electron collectors in dye-sensitized solar cells.

    PubMed

    Chua, Julianto; Mathews, Nripan; Jennings, James R; Yang, Guangwu; Wang, Qing; Mhaisalkar, Subodh G

    2011-11-21

    We describe the application of 3-dimensional metal grid electrodes (3D-MGEs) as electron collectors in dye-sensitized solar cells (DSCs) as a replacement for fluorinated tin oxide (FTO) electrodes. Requirements, structure, advantages, and limitations of the metal grid electrodes are discussed. Solar conversion efficiencies of 6.2% have been achieved in 3D-MGE based solar cells, comparable to that fabricated on FTO (7.1%). The charge transport properties and collection efficiencies in these novel solar cells have been studied using electrochemical impedance spectroscopy. PMID:21989708

  5. Dye-sensitized solar cell comprising polyethyl methacrylate doped with ammonium iodide solid polymer electrolyte

    NASA Astrophysics Data System (ADS)

    Singh, Vivek Kr.; Bhattacharya, B.; Shukla, S.; Singh, Pramod K.

    2014-09-01

    The aim of the present work was to develop a new solid electrolyte polyethyl methacrylate doped with ammonium iodide polymer electrolyte and its application in dye-sensitized solar cell (DSSC). The electrical, structural and photoelectrochemical properties of polymer electrolytes are presented in detail. DSSCs have been fabricated and characterized. The polymer electrolyte film with maximum ionic conductivity shows maximum efficient DSSC of efficiency 0.43 % at 1 sun condition.

  6. Dye-sensitized solar cell comprising polyethyl methacrylate doped with ammonium iodide solid polymer electrolyte

    NASA Astrophysics Data System (ADS)

    Singh, Vivek Kr.; Bhattacharya, B.; Shukla, S.; Singh, Pramod K.

    2015-03-01

    The aim of the present work was to develop a new solid electrolyte polyethyl methacrylate doped with ammonium iodide polymer electrolyte and its application in dye-sensitized solar cell (DSSC). The electrical, structural and photoelectrochemical properties of polymer electrolytes are presented in detail. DSSCs have been fabricated and characterized. The polymer electrolyte film with maximum ionic conductivity shows maximum efficient DSSC of efficiency 0.43 % at 1 sun condition.

  7. A strategy to design novel structure photochromic sensitizers for dye-sensitized solar cells.

    PubMed

    Wu, Wenjun; Wang, Jiaxing; Zheng, Zhiwei; Hu, Yue; Jin, Jiayu; Zhang, Qiong; Hua, Jianli

    2015-01-01

    Two sensitizers with novel structure were designed and synthetized by introducing photochromic bisthienylethene (BTE) group into the conjugated system. Thanks to the photochromic effect the sensitizers have under ultraviolet and visible light, the conjugated bridge can be restructured and the resulting two photoisomers showed different behaviors in photovoltaic devices. This opens up a new research way for the dye-sensitized solar cells (DSSCs). PMID:25716204

  8. A strategy to design novel structure photochromic sensitizers for dye-sensitized solar cells

    PubMed Central

    Wu, Wenjun; Wang, Jiaxing; Zheng, Zhiwei; Hu, Yue; Jin, Jiayu; Zhang, Qiong; Hua, Jianli

    2015-01-01

    Two sensitizers with novel structure were designed and synthetized by introducing photochromic bisthienylethene (BTE) group into the conjugated system. Thanks to the photochromic effect the sensitizers have under ultraviolet and visible light, the conjugated bridge can be restructured and the resulting two photoisomers showed different behaviors in photovoltaic devices. This opens up a new research way for the dye-sensitized solar cells (DSSCs). PMID:25716204

  9. Metal complex-based electron-transfer mediators in dye-sensitized solar cells

    DOEpatents

    Elliott, C. Michael; Sapp, Shawn A.; Bignozzi, Carlo Alberto; Contado, Cristiano; Caramori, Stefano

    2006-03-28

    This present invention provides a metal-ligand complex and methods for using and preparing the same. In particular, the metal-ligand complex of the present invention is of the formula: L.sub.a-M-X.sub.b where L, M, X, a, and b are those define herein. The metal-ligand complexes of the present invention are useful in a variety of applications including as electron-transfer mediators in dye-sensitized solar cells and related photoelectrochromic devices.

  10. Monobenzoporphyrins as Sensitizers for Dye-Sensitized Solar Cells: Observation of Significant Spacer-Group Effect.

    PubMed

    Jinadasa, R G Waruna; Li, Bihong; Schmitz, Benjamin; Kumar, Siddhartha; Hu, Yi; Kerr, Lei; Wang, Hong

    2016-08-23

    A series of monobenzoporphyrins (WH1-WH4) bearing different conjugated spacer groups were designed and synthesized as sensitizers for dye-sensitized solar cells. Although a phenyl spacer only has a minimal impact on the absorption bands of the monobenzoporphyrin, an ethynylphenyl (WH3) or a vinyl (WH4) spacer redshifts and broadens the absorption bands of the dyes to result in much enhanced light-harvesting ability. Dye-sensitized solar cells based on these monobenzoporphyrin dyes displayed remarkable differences in power conversion efficiencies (PCEs). The monobenzoporphyrin bearing no spacer (WH1) resulted in a PCE of only 0.5 %; in contrast, the monobenzoporphyrin bearing vinyl spacers (WH4) achieved a PCE of 5.2 %. The high efficiency of the WH4 cell is attributed to the higher light-harvesting ability, the lesser extent of aggregation on the TiO2 surface, and the more favorable electron-density distributions of the HOMO and LUMO for electron injection and collection. This work demonstrates the exceptional tunability of benzoporphyrins as sensitizers for dye-sensitized solar cells. PMID:27469616

  11. Surface modifications of photoanodes in dye sensitized solar cells: enhanced light harvesting and reduced recombination

    NASA Astrophysics Data System (ADS)

    Saxena, Vibha; Aswal, D. K.

    2015-06-01

    In a quest to harvest solar power, dye-sensitized solar cells (DSSCs) have potential for low-cost eco-friendly photovoltaic devices. The major processes which govern the efficiency of a DSSC are photoelectron generation, injection of photo-generated electrons to the conduction band (CB) of the mesoporous nanocrystalline semiconductor (nc-SC); transport of CB electrons through nc-SC and subsequent collection of CB electrons at the counter electrode (CE) through the external circuit; and dye regeneration by redox couple or hole transport layer (HTL). Most of these processes occur at various interfaces of the photoanode. In addition, recombination losses of photo-generated electrons with either dye or redox molecules take place at the interfaces. Therefore, one of the key requirements for high efficiency is to improve light harvesting of the photoanode and to reduce the recombination losses at various interfaces. In this direction, surface modification of the photoanode is the simplest method among the various other approaches available in the literature. In this review, we present a comprehensive discussion on surface modification of the photoanode, which has been adopted in the literature for not only enhancing light harvesting but also reducing recombination. Various approaches towards surface modification of the photoanode discussed are (i) fluorine-doped tin oxide (FTO)/nc-SC interface modified via a compact layer of semiconductor material which blocks exposed sites of FTO to electrolyte (or HTL), (ii) nc-SC/dye interface modification either through acid treatment resulting in enhanced dye loading due to a positively charged surface or by depositing insulating/semiconducting blocking layer on the nc-SC surface, which acts as a tunneling barrier for recombination, (iii) nc-SC/dye interface modified by employing co-adsorbents which helps in reducing the dye aggregation and thereby recombination, and (iv) dye/electrolyte (or dye/HTL) interface modification using

  12. Electronic structures and optical properties of organic dye sensitizer NKX derivatives for solar cells: a theoretical approach.

    PubMed

    Zhang, Cai-Rong; Liu, Li; Liu, Zi-Jiang; Shen, Yu-Lin; Sun, Yi-Tong; Wu, You-Zhi; Chen, Yu-Hong; Yuan, Li-Hua; Wang, Wei; Chen, Hong-Shan

    2012-09-01

    The photon to current conversion efficiency of dye-sensitized solar cells (DSCs) can be significantly affected by dye sensitizers. The design of novel dye sensitizers with good performance in DSCs depend on the dye's information about electronic structures and optical properties. Here, the geometries, electronic structures, as well as the dipole moments and polarizabilities of organic dye sensitizers C343 and 20 kinds of NKX derivatives were calculated using density functional theory (DFT), and the computations of the time dependent DFT with different functionals were performed to explore the electronic absorption properties. Based upon the calculated results and the reported experimental work, we analyzed the role of different conjugate bridges, chromophores, and electron acceptor groups in tuning the geometries, electronic structures, optical properties of dye sensitizers, and the effects on the parameters of DSCs were also investigated. PMID:23117291

  13. Correction: Enhanced photoresponse in dye-sensitized solar cells via localized surface plasmon resonance through highly stable nickel nanoparticles

    NASA Astrophysics Data System (ADS)

    Rahman, Md. Mahbubur; Im, Sang Hyuk; Lee, Jae-Joon

    2016-03-01

    Correction for `Enhanced photoresponse in dye-sensitized solar cells via localized surface plasmon resonance through highly stable nickel nanoparticles' by Md. Mahbubur Rahman et al., Nanoscale, 2016, DOI: 10.1039/c5nr08155f.

  14. Correction: Enhanced photoresponse in dye-sensitized solar cells via localized surface plasmon resonance through highly stable nickel nanoparticles.

    PubMed

    Rahman, Md Mahbubur; Im, Sang Hyuk; Lee, Jae-Joon

    2016-04-14

    Correction for 'Enhanced photoresponse in dye-sensitized solar cells via localized surface plasmon resonance through highly stable nickel nanoparticles' by Md. Mahbubur Rahman et al., Nanoscale, 2016, DOI: 10.1039/c5nr08155f. PMID:26991406

  15. Functionalized graphene sheets in dye-sensitized solar cell counter electrodes

    NASA Astrophysics Data System (ADS)

    Roy-Mayhew, Joseph Dominic

    The use of thermally exfoliated graphite oxide, commonly referred to as functionalized graphene sheets (FGSs), was investigated as a catalytic counter electrode material in dye-sensitized solar cells to substitute for platinum nanoparticles traditionally used in devices. A catalyst's activity depends both on the material's intrinsic activity as well as on its surface area accessible for reaction. Thus, this work aimed i) to determine the intrinsic activity of FGSs with various chemical compositions and structures, and ii) to create high surface area networks of FGSs to use as catalytic electrodes in dye-sensitized solar cells. Monolayers of FGSs were fabricated and electrochemically tested to determine the intrinsic catalytic activity for a common dye-sensitized solar cell redox mediator, cobalt bipyridine. It was found that lattice defect rich, oxygen-site poor FGSs catalyze the reduction of the cobalt complex as well as platinum does, exhibiting a rate constant of ~ 6 x 10-3 cm/s. This rate is an order of magnitude faster than exhibited with oxygen-site rich graphene oxide, and over two orders of magnitude faster than found with the basal plane of graphite (as a surrogate for pristine graphene). FGSs are less catalytic towards the iodide/triiodide redox mediator, thus larger surface areas must be used for effective catalysis. In this work, conductive, high surface area networks of FGSs were produced by first tape casting surfactant-stabilized aqueous suspensions of FGSs and then thermolyzing the surfactant materials. Iodide/triiodide mediated dye-sensitized solar cells using these FGS electrodes exhibited power conversion efficiencies within 10% of devices using platinum nanoparticles. Furthermore, to interpret the catalytic activity of FGSs towards the reduction of triiodide, a new electrochemical impedance spectroscopy equivalent circuit was proposed that matches the observed spectra features to the appropriate phenomena. Lastly, improved catalytic performance

  16. Integration of biological photonic crystals in dye-sensitized solar cells for enhanced photocurrent generation

    NASA Astrophysics Data System (ADS)

    Campbell, Jeremy; Rorrer, Greg

    2013-10-01

    Dye-sensitized solar cells (DSSCs) rely on a network of titanium dioxide nanoparticles for electron transport and must balance carrier generation and collection. Adding photonic structures may increase light capture without affecting carrier collection. Diatoms are single-celled algae that biologically fabricate silicon dioxide cell walls which resemble photonic crystal slabs. We present a simple fabrication strategy that allows for uniform and controlled placement of biosilica within DSSCs. Integration of biosilica reduces photoanode transmittance to less than 5% prior to dye sensitization at loading levels as low as 6 wt% biosilica. Increased biosilica loading (17 wt%) provides additional enhancements in photocurrent generation. Reflectance measurements suggest that the enhancement results from the combined effects of photonic resonance and Mie scattering. Overall efficiency of these devices is improved by 8% and 14%, respectively.

  17. Potential complex of rhodamine B and copper (II) for dye sensitizer on solar cell

    NASA Astrophysics Data System (ADS)

    Setyawati, Harsasi; Purwaningsih, Aning; Darmokoesoemo, Handoko; Hamami, Rochman, Faidur; Permana, Ahmadi Jaya

    2016-03-01

    A complex from copper(II) and rhodamine B as ligand was synthesized, characterized and applied as potential dye sensitizer on solar cell. A complex was synthesized from the reaction of copper(II) salts and rhodamine B with mole ratio 1:3. A complex showing Metal Ligand Charge Transfer (MLCT) phenomenon at 260 nm. Metal-ligand bonding through carbonyl (CO) groups at 617.22 cm-1 and methoxy (CH3O) groups at 339.47 cm-1. Electrical conductivity analysis confirms that the complex was ionic compound. The complex was applied as potential dye sensitizer with open circuit voltage 0.48775 V, short circuit current 0.01025 mA/cm2 and efficiency 0.0039 %.

  18. TiO2 films with rich bulk oxygen vacancies prepared by electrospinning for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Li, Xiaodong; Gao, Caitian; Wang, Jiangtao; Lu, Bingan; Chen, Wanjun; Song, Jie; Zhang, Shanshan; Zhang, Zhenxing; Pan, Xiaojun; Xie, Erqing

    2012-09-01

    Highly transparent nanocrystalline TiO2 films have been fabricated by electrospinning (ES) technique based on a transmutation process from as-spun nanofibers with an appropriate amount of tri-ethanolamine (TEOA) added to the precursor. A possible evolution mechanism of the transparent nanocrystalline TiO2 films is proposed. It is found that the films prepared via transmutation from electrospun nanofibers possess rich bulk oxygen vacancies (BOVs, PL band at 621-640 nm) by using photoluminescence (PL) spectroscopy. Contrastively, the dominant peak in PL spectrum of the spin-coated film is the emission from surface oxygen vacancies (SOVs, PL band at 537-555 nm). The electrospun TiO2 films with rich BOVs induce large open-circuit voltage (Voc) and fill factor (FF) improvements in dye-sensitized solar cells (DSCs), and thus a large improvement of energy conversion efficiency (η). In addition, these performance advantages are maintained for a double-layer cell with a doctor-bladed ˜7 μm top layer (P25 nanometer TiO2, Degussa) and an electrospun ˜3 μm bottom layer. The double-layer cell yields a high η of 6.01%, which has increased by 14% as compared with that obtained from a 10 μm thick P25 film.

  19. Detailed investigations of ZnO photoelectrodes preparation for dye sensitized solar cells.

    PubMed

    Marczak, Renata; Werner, Fabian; Ahmad, Rameez; Lobaz, Volodymyr; Guldi, Dirk M; Peukert, Wolfgang

    2011-04-01

    Wurtzite ZnO hexagonal nanopyramids were successfully synthesized in the liquid phase from homogeneous methanolic solutions of zinc acetate and tetramethylammonium hydroxide at an excess of zinc ions. The formation and properties of the nanocrystals were examined as a function of synthesis conditions. No significant influence of the [Zn(2+)]/[OH(-)] ratio was noticed on the final particle size, in spite of increased amounts of OH(-) ions, which tend to accelerate the particle nucleation and growth. Nevertheless, the reactant concentration ratio influences the surface properties of the ZnO nanocrystals. Mesoporous ZnO films were prepared by doctor blading ethanolic pastes containing ZnO nanoparticles and ethyl cellulose onto FTO conductive glass substrate followed by calcination. Additionally, the influence of a plasticizer (triacetin)-used during the paste preparation-on the film quality was investigated. A higher content of ZnO nanoparticles and plasticizer in the pastes improved the film quality. Four different temperatures (i.e., 400, 425, 450, and 475 °C) were used for the film calcination and their influence on the structural properties of the films was characterized. In principle, increasing the calcination temperature goes hand in hand with an increase of particle size, as well as the pore diameter and reduction of the surface area. Suitable mesoporous films were employed as photoanodes in dye sensitized solar cells (DSSCs). In order to assess the effect of the varied parameters on complete DSSC devices-using cis-diisothiocyanato-bis(2,2'-bipyridyl-4,4'-dicarboxylato) ruthenium(II)bis(tetrabutylammonium (N719) as a sensitizer-incident photon to current efficiency (IPCE) and current voltage measurements were carried out. The IPCE measurements confirmed photoinduced electron injection from the dye, reaching IPCE values up to 76%. Furthermore, current-voltage characteristics of complete cells emphasized the importance of the proper preparation methods and

  20. Preparation of flexible TiO2 photoelectrodes for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Li, Wen-Ren; Wang, Hsiu-Hsuan; Lin, Chia-Feng; Su, Chaochin

    2014-09-01

    Dye-sensitized solar cells (DSSCs) based on nanocrystalline TiO2 photoelectrodes on indium tin oxide (ITO) coated polymer substrates have drawn great attention due to its lightweight, flexibility and advantages in commercial applications. However, the thermal instability of polymer substrates limits the process temperature to below 150 °C. In order to assure high and firm interparticle connection between TiO2 nanocrystals (TiO2-NC) and polymer substrates, the post-treatment of flexible TiO2 photoelectrodes (F-TiO2-PE) by mechanical compression was employed. In this work, Degussa P25 TiO2-NC was mixed with tert-butyl alcohol and DI-water to form TiO2 paste. F-TiO2-PE was then prepared by coating the TiO2 paste onto ITO coated polyethylene terephthalate (PET) substrate using doctor blade followed by low temperature sintering at 120 °C for 2 hours. To study the effect of mechanical compression, we applied 50 and 100 kg/cm2 pressure on TiO2/PET to complete the fabrication of F-TiO2-PE. The surface morphology of F-TiO2-PE was characterized using scanning electron microscopy. The resultant F-TiO2-PE sample exhibited a smooth, crack-free structure indicating the great improvement in the interparticle connection of TiO2-NC. Increase of compression pressure could lead to the increase of DSSC photoconversion efficiency. The best photoconversion efficiency of 4.19 % (open circuit voltage (Voc) = 0.79 V, short-circuit photocurrent density (Jsc) = 7.75 mA/cm2, fill factor (FF) = 0.68) was obtained for the F-TiO2-PE device, which showed great enhancement compared with the F-TiO2-PE cell without compression treatment. The effect of compression in DSSC performance was vindicated by the electrochemical impedance spectroscopy measurement.

  1. Dye sensitization of nanocrystalline titanium dioxide with square planar platinum(II) diimine dithiolate complexes.

    PubMed

    Islam, A; Sugihara, H; Hara, K; Singh, L P; Katoh, R; Yanagida, M; Takahashi, Y; Murata, S; Arakawa, H; Fujihashi, G

    2001-10-01

    A series of platinum-based sensitizers of the general type Pt(NN)(SS), where NN is 4,4'-dicarboxy-2,2'-bipyridine (dcbpy) or 4,7-dicarboxy-1,10-phenanthroline (dcphen) and SS is ethyl-2-cyano-3,3-dimercaptoacrylate (ecda), quinoxaline-2,3-dithiolate (qdt), 1,2-benzenedithiolate (bdt), or 3,4-toluenedithiolate (tdt), that have various ground-state oxidation potentials has been synthesized and anchored to nanocrystalline titanium dioxide electrodes for light-to-electricity conversion in regenerative photoelectrochemical cells with an I(-)/I(-)(3) acetonitrile electrolyte. The intense mixed-Pt/dithiolate-to-diimine charge-transfer absorption bands in this series could be tuned from 440 to 580 nm by choosing appropriate dithiolate ligands, and the highest occupied molecular orbitals varied by more than 500 mV. Spectrophotometric titration of the Pt(dcphen)(bdt) complex exhibits a ground-state pK(a) value of 3.2 +/- 0.1, which can be assigned to the protonation of the carboxylate group of the dcphen ligand. Binding of Pt(dcbpy)(qdt) to porous nanostructured TiO(2) films was analyzed using the Langmuir adsorption isotherm model, yielding an adsorption equilibrium constant of 4 x 10(5) M(-1). The amount of dye adsorbed at the surface of TiO(2) films was 9.5 x 10(-8) mol/cm(2), which is ca. 50% lower than the full monolayer coverage. The resulting complexes efficiently sensitized TiO(2) over a notably broad spectral range and showed an open-circuit potential of ca. 600 mV with an impressive fill factor of > 0.70, making them attractive candidates for solar energy conversion applications. The visible spectra of the 3,4-toluenedithiol-based sensitizers showed an enhanced red response, but the lower photocurrent efficiency observed for these sensitizers stems in part from a sluggish halide oxidation rate and a fast recombination of injected electrons with the oxidized dye. PMID:11578182

  2. ZnO disk-like structures and their application in dye sensitized solar cell

    NASA Astrophysics Data System (ADS)

    Wang, J. X.; Yang, Y.; Sun, X. W.

    2016-08-01

    Hexagonal ZnO nanodisks, nanorings and porous nanodisks were synthesized by a simple hydrothermal method. The morphologies, structure and their optical properties of the various ZnO disk-like structures were characterized and their growth mechanism was investigated. The prepared ZnO disk-like nanostructures were used in the fabrication of the dye-sensitized solar cells. Improved photovoltaic properties were achieved for the porous disk solar cells due to their special geometry enabled better light harvesting and reduced recombination.

  3. Enhanced charge carrier generation in dye sensitized solar cells by nanoparticle plasmons

    NASA Astrophysics Data System (ADS)

    Hägglund, Carl; Zäch, Michael; Kasemo, Bengt

    2008-01-01

    An interesting possibility to improve the conversion and cost efficiencies of photovoltaic solar cells is to exploit the large optical cross sections of localized (nanoparticle) surface plasmon resonances (LSPRs). We have investigated this prospect for dye sensitized solar cells. Photoconductivity measurements were performed on flat TiO2 films, sensitized by a combination of dye molecules and arrays of nanofabricated elliptical gold disks. An enhanced dye charge carrier generation rate was found and shown to derive from the LSPR contribution by means of the polarization dependent resonance frequency in the anisotropic, aligned gold disks.

  4. The durability of the dye-sensitized solar cell with silicon resin

    NASA Astrophysics Data System (ADS)

    Ki, Hyun Chul; Kim, Seon Hoon; Kim, Doo-Gun; Kim, Tae-Un; Jung, Haeng-Yun; Yoon, Jae-Man

    2015-03-01

    Dye-Sensitized solar cell (DSSC) is expected to be one of the next-generation photovoltaics because of its environment-friendly and low-cost properties. However, commercialization of DSSC is difficult because of the electrolyte leakage. We propose a new thermal curable base on silicon resin. The resin aimed at sealing of DSSC and gives a promising resolution for sealing of practical DSSC. Furthermore, the optimized resin was fabricated into solar cells, which exhibited best durability by retaining 97% of the initial photoelectric conversion efficiency after 1,000 hours tracking test at 80°C.

  5. High-performance dye-sensitized solar cells based on solvent-free electrolytes produced from eutectic melts.

    PubMed

    Bai, Yu; Cao, Yiming; Zhang, Jing; Wang, Mingkui; Li, Renzhi; Wang, Peng; Zakeeruddin, Shaik M; Grätzel, Michael

    2008-08-01

    Low-cost excitonic solar cells based on organic optoelectronic materials are receiving an ever-increasing amount of attention as potential alternatives to traditional inorganic photovoltaic devices. In this rapidly developing field, the dye-sensitized solar cell (DSC) has achieved so far the highest validated efficiency of 11.1% (ref. 2) and remarkable stability. However, the cells with the best performance use volatile solvents in their electrolytes, which may be prohibitive for outdoor solar panels in view of the need for robust encapsulation. Solvent-free room-temperature ionic liquids have been pursued as an attractive solution to this dilemma, and device efficiencies of over 7% were achieved by using some low-viscosity formulations containing 1-ethyl-3-methylimidazolium thiocyanate, selenocyanate, tricyanomethide or tetracyanoborate. Unfortunately, apart from tetracyanoborate, all of these low-viscosity melts proved to be unstable under prolonged thermal stress and light soaking. Here, we introduce the concept of using eutectic melts to produce solvent-free liquid redox electrolytes. Using a ternary melt in conjunction with a nanocrystalline titania film and the amphiphilic heteroleptic ruthenium complex Z907Na (ref. 10) as a sensitizer, we reach excellent stability and an unprecedented efficiency of 8.2% under air-mass 1.5 global illumination. Our results are of importance to realize large-scale outdoor applications of mesoscopic DSCs. PMID:18587401

  6. High-performance dye-sensitized solar cells based on solvent-free electrolytes produced from eutectic melts

    NASA Astrophysics Data System (ADS)

    Bai, Yu; Cao, Yiming; Zhang, Jing; Wang, Mingkui; Li, Renzhi; Wang, Peng; Zakeeruddin, Shaik M.; Grätzel, Michael

    2008-08-01

    Low-cost excitonic solar cells based on organic optoelectronic materials are receiving an ever-increasing amount of attention as potential alternatives to traditional inorganic photovoltaic devices. In this rapidly developing field, the dye-sensitized solar cell (DSC) has achieved so far the highest validated efficiency of 11.1% (ref. 2) and remarkable stability. However, the cells with the best performance use volatile solvents in their electrolytes, which may be prohibitive for outdoor solar panels in view of the need for robust encapsulation. Solvent-free room-temperature ionic liquids have been pursued as an attractive solution to this dilemma, and device efficiencies of over 7% were achieved by using some low-viscosity formulations containing 1-ethyl-3-methylimidazolium thiocyanate, selenocyanate, tricyanomethide or tetracyanoborate. Unfortunately, apart from tetracyanoborate, all of these low-viscosity melts proved to be unstable under prolonged thermal stress and light soaking. Here, we introduce the concept of using eutectic melts to produce solvent-free liquid redox electrolytes. Using a ternary melt in conjunction with a nanocrystalline titania film and the amphiphilic heteroleptic ruthenium complex Z907Na (ref. 10) as a sensitizer, we reach excellent stability and an unprecedented efficiency of 8.2% under air-mass 1.5 global illumination. Our results are of importance to realize large-scale outdoor applications of mesoscopic DSCs.

  7. Photocurrent enhanced by singlet fission in a dye-sensitized solar cell.

    PubMed

    Schrauben, Joel N; Zhao, Yixin; Mercado, Candy; Dron, Paul I; Ryerson, Joseph L; Michl, Josef; Zhu, Kai; Johnson, Justin C

    2015-02-01

    Investigations of singlet fission have accelerated recently because of its potential utility in solar photoconversion, although only a few reports definitively identify the role of singlet fission in a complete solar cell. Evidence of the influence of singlet fission in a dye-sensitized solar cell using 1,3-diphenylisobenzofuran (DPIBF, 1) as the sensitizer is reported here. Self-assembly of the blue-absorbing 1 with co-adsorbed oxidation products on mesoporous TiO2 yields a cell with a peak internal quantum efficiency of ∼70% and a power conversion efficiency of ∼1.1%. Introducing a ZrO2 spacer layer of thickness varying from 2 to 20 Å modulates the short-circuit photocurrent such that it is initially reduced as thickness increases but 1 with 10-15 Å of added ZrO2. This rise can be explained as being due to a reduced rate of injection of electrons from the S1 state of 1 such that singlet fission, known to occur with a 30 ps time constant in polycrystalline films, has the opportunity to proceed efficiently and produce two T1 states per absorbed photon that can subsequently inject electrons into TiO2. Transient spectroscopy and kinetic simulations confirm this novel mode of dye-sensitized solar cell operation and its potential utility for enhanced solar photoconversion. PMID:25607825

  8. Electron Injection at Dye-Sensitized Semiconductor Electrodes

    NASA Astrophysics Data System (ADS)

    Watson, David F.; Meyer, Gerald J.

    2005-05-01

    Electron injection at dye-sensitized semiconductors is reviewed. Particular emphasis is placed on theoretical and photoelectrochemical studies of dye-sensitized planar and single-crystal electrodes. The accepted mechanism of electron injection, which was derived from these classical studies, is introduced. Selected photoelectrochemical studies of dye-sensitized nanocrystalline semiconductors are reviewed; emphasis is given to factors that influence the efficiencies of electron injection and charge recombination. The development of quasi-solid-state nanocrystalline dye-sensitized solar cells is also discussed. Recent time-resolved spectroscopic studies of electron injection and charge recombination are reviewed. These studies have led to a better understanding of electron injection mechanisms, and have revealed the limitations of the classical models.

  9. Design and characterisation of bodipy sensitizers for dye-sensitized NiO solar cells.

    PubMed

    Summers, Gareth H; Lefebvre, Jean-François; Black, Fiona A; Davies, E Stephen; Gibson, Elizabeth A; Pullerits, Tönu; Wood, Christopher J; Zidek, Karel

    2016-01-14

    A series of photosensitizers for NiO-based dye-sensitized solar cells is presented. Three model compounds containing a triphenylamine donor appended to a boron dipyrromethene (bodipy) chromophore have been successfully prepared and characterised using emission spectroscopy, electrochemistry and spectroelectrochemistry, to ultimately direct the design of dyes with more complex structures. Carboxylic acid anchoring groups and thiophene spacers were appended to the model compounds to provide five dyes which were adsorbed onto NiO and integrated into dye-sensitized solar cells. Solar cells incorporating the simple Bodipy-CO₂H dye were surprisingly promising relative to the more complex dye 4. Cell performances were improved with dyes which had increased electronic communication between the donor and acceptor, achieved by incorporating a less hindered bodipy moiety. Further increases in performances were obtained from dyes which contained a thiophene spacer. Thus, the best performance was obtained for 7 which generated a very promising photocurrent density of 5.87 mA cm(-2) and an IPCE of 53%. Spectroelectrochemistry combined with time-resolved transient absorption spectroscopy were used to determine the identity and lifetime of excited state species. Short-lived (ps) transients were recorded for 4, 5 and 7 which are consistent with previous studies. Despite a longer lived (25 ns) charge-separated state for 6/NiO, there was no increase in the photocurrent generated by the corresponding solar cell. PMID:26660278

  10. Surface plasma resonant effect of gold nanoparticles on the photoelectrodes of dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Meen, Teen-Hang; Tsai, Jenn-Kai; Chao, Shi-Mian; Lin, Yu-Chien; Wu, Tien-Chuan; Chang, Tang-Yun; Ji, Liang-Wen; Water, Walter; Chen, Wen-Ray; Tang, I.-Tseng; Huang, Chien-Jung

    2013-10-01

    In this study, we prepared different shapes of gold nanoparticles by seed-mediated growth method and applied them on the photoelectrodes of dye-sensitized solar cells (DSSCs) to study the surface plasma resonant (SPR) effect of gold nanoparticles on the photoelectrodes of dye-sensitized solar cells. The analyses of field emission scanning electron microscopy show that the average diameter of the spherical gold nanoparticles is 45 nm, the average length and width of the short gold nanorods were 55 and 22 nm, respectively, and the average length and width of the long gold nanorods were 55 and 14 nm, respectively. The aspect ratio of the short and long gold nanorods was about 2.5 and 4, respectively. The results of ultraviolet-visible absorption spectra show that the absorption wavelength is about 540 nm for spherical gold nanoparticles, and the absorption of the gold nanorods reveals two peaks. One is about 510 to 520 nm, and the other is about 670 and 710 nm for the short and long gold nanorods, respectively. The best conversion efficiency of the dye-sensitized solar cells with spherical gold nanoparticles and short and long gold nanorods added in is 6.77%, 7.08%, and 7.29%, respectively, and is higher than that of the cells without gold nanoparticles, which is 6.21%. This result indicates that the effect of gold nanoparticles on the photoelectrodes can increase the conductivity and reduce the recombination of charges in the photoelectrodes, resulting in the increase of conversion efficiency for DSSCs. In addition, the long gold nanorods have stronger SPR effect than the spherical gold nanoparticles and short gold nanorods at long wavelength. This may be the reason for the higher conversion efficiency of DSSCs with long gold nanorods than those of the cells with spherical gold nanoparticles and short gold nanorods.

  11. Self-assembled ultra small ZnO nanocrystals for dye-sensitized solar cell application

    SciTech Connect

    Patra, Astam K.; Dutta, Arghya; Bhaumik, Asim

    2014-07-01

    We demonstrate a facile chemical approach to produce self-assembled ultra-small mesoporous zinc oxide nanocrystals using sodium salicylate (SS) as a template under hydrothermal conditions. These ZnO nanomaterials have been successfully fabricated as a photoanode for the dye-sensitized solar cell (DSSC) in the presence of N719 dye and iodine–triiodide electrolyte. The structural features, crystallinity, purity, mesophase and morphology of the nanostructure ZnO are investigated by several characterization tools. N{sub 2} sorption analysis revealed high surface areas (203 m{sup 2} g{sup −1}) and narrow pore size distributions (5.1–5.4 nm) for different samples. The mesoporous structure and strong photoluminescence facilitates the high dye loading at the mesoscopic void spaces and light harvesting in DSSC. By utilizing this ultra-small ZnO photoelectrode with film thickness of about 7 μm in the DSSC with an open-circuit voltage (V{sub OC}) of 0.74 V, short-circuit current density (J{sub SC}) of 3.83 mA cm{sup −2} and an overall power conversion efficiency of 1.12% has been achieved. - Graphical abstract: Ultra-small ZnO nanocrystals have been synthesized with sodium salicylate as a template and using it as a photoanode in a dye-sensitized solar cell 1.12% power conversion efficiency has been observed. - Highlights: • Synthesis of self-assembled ultra-small mesoporous ZnO nanocrystals by using sodium salicylate as a template. • Mesoporous ZnO materials have high BET surface areas and void space. • ZnO nanoparticles serve as a photoanode for the dye-sensitized solar cell (DSSC). • Using ZnO nanocrystals as photoelectrode power conversion efficiency of 1.12% has been achieved.

  12. Nitrogen-doped graphene as transparent counter electrode for efficient dye-sensitized solar cells

    SciTech Connect

    Wang, Guiqiang; Fang, Yanyan; Lin, Yuan; Xing, Wei; Zhuo, Shuping

    2012-12-15

    Graphical abstract: Display Omitted Highlights: ► NG sheets are prepared through a hydrothermal reduction of graphite oxide. ► The transparent NG counter electrodes of DSCs are fabricated at room temperature. ► Transparent NG electrode exhibits excellent catalytic activity for the reduction of I{sub 3}{sup −}. ► The DSC with NG electrode achieves a comparable efficiency to that of the Pt-based cell. ► The efficiency of rear illumination is about 85% that of front illumination. -- Abstract: Nitrogen-doped graphene sheets are prepared through a hydrothermal reduction of graphite oxide in the presence of ammonia and applied to fabricate the transparent counter electrode of dye-sensitized solar cells. The atomic percentage of nitrogen in doped graphene sample is about 2.5%, and the nitrogen bonds display pyridine and pyrrole-like configurations. Cyclic voltammetry studies demonstrate a much higher electrocatalytic activity toward I{sup −}/I{sub 3}{sup −} redox reaction for nitrogen-doped graphene, as compared with pristine graphene. The dye-sensitized solar cell with this transparent nitrogen-doped graphene counter electrode shows conversion efficiencies of 6.12% and 5.23% corresponding to front-side and rear-side illumination, respectively. Meanwhile, the cell with a Pt counter electrode shows a conversion efficiency of 6.97% under the same experimental condition. These promising results highlight the potential application of nitrogen-doped graphene in cost-effective, transparent dye-sensitized solar cells.

  13. Control of Electron Transfer Pathways in a Dye-Sensitized Solar Cell

    SciTech Connect

    Brueggemann, Ben; Organero, Juan Angel; Pascher, Torbjoern; Pullerits, Tonu; Yartsev, Arkady

    2006-11-17

    Using shaped laser pulses, we increase the yield of ultrafast electron injection from the sensitizer to TiO{sub 2} nanocrystals in the core part of a dye-sensitized solar cell. The temporal structure of the optimized excitation pulse is in clear correlation with nuclear oscillations in the impulsively excited dye molecule. From DFT structure optimization and normal mode analyses we identified the modes which are responsible for the oscillations. The best pulse shape suggests Impulsive Stimulated (anti-Stokes) Raman scattering as a key process of optimization.

  14. Multifunctional Interface Modification of Energy Relay Dye in Quasi-solid Dye-sensitized Solar Cells

    PubMed Central

    Gao, Rui; Cui, Yixiu; Liu, Xiaojiang; Wang, Liduo

    2014-01-01

    In this paper, 4-(dicyanomethylene)-2-t-butyl-6(1,1,7,7-tetramethyljulolidyl-9-enyl)-4H-pyran (DCJTB) has been used in interface modification of dye-sensitized solar cells (DSCs) with combined effects of retarding charge recombination and Förster resonant energy transfer (FRET). DCJTB interface modification significantly improved photovoltaic performance of DSCs. I–V curves shows the conversion efficiency increases from 4.27% to 5.64% with DCJTB coating. The application of DCJTB with combined effects is beneficial to explore more novel multi-functional interface modification materials to improve the performance of DSCs. PMID:24993900

  15. Conducting polymers based counter electrodes for dye-sensitized solar cells

    SciTech Connect

    Veerender, P. E-mail: veeru1009@gmail.com; Saxena, Vibha E-mail: veeru1009@gmail.com; Gusain, Abhay E-mail: veeru1009@gmail.com; Jha, P. E-mail: veeru1009@gmail.com; Koiry, S. P. E-mail: veeru1009@gmail.com; Chauhan, A. K. E-mail: veeru1009@gmail.com; Aswal, D. K. E-mail: veeru1009@gmail.com; Gupta, S. K. E-mail: veeru1009@gmail.com

    2014-04-24

    Conducting polymer films were synthesized and employed as an alternative to expensive platinum counter electrodes for dye-sensitized solar cells. poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS) thin films were spin-coated and polypyrrole films were electrochemically deposited via cyclic voltammetry method on ITO substrates. The morphology of the films were imaged by SEM and AFM. These films show good catalytic activity towards triiodide reduction as compared to Pt/FTO electrodes. Finally the photovoltaic performance of DSSC fabricated using N3 dye were compared with PT/FTO, PEDOT/ITO, and e-PPy counter electrodes.

  16. Theoretical evidence of multiple dye regeneration mechanisms in dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Liu, Tao; Troisi, Alessandro

    2013-05-01

    The multiple regeneration mechanisms in dye-sensitized solar cells (DSSC), with N3 (Ru(dcbpy)2(NCS)2) as dye and I-/I3- as redox shuttle, have been studied by DFT methods. Our results show that different reaction pathways are possible within the same dye and the actual mechanism is controlled by the initial geometry of the dyeI complex. By considering the rapid interconversion between different N3I geometries, the reaction mechanism where N3I dissociates into neutral dye and Irad radical is preferred to the mechanism where N3I reacts with a second iodide.

  17. Benzoporphyrins: Selective Co-sensitization in Dye-Sensitized Solar Cells.

    PubMed

    Lodermeyer, Fabian; Costa, Rubén D; Malig, Jenny; Jux, Norbert; Guldi, Dirk M

    2016-06-01

    A novel class of dyes, namely benzoporphyrins, was synthesized and implemented into dye-sensitized solar cells. They feature complementary absorptions compared to N719, which renders them promising candidates for co-sensitization in DSSCs. Notably, metallated benzoporphyrins reveal a TiO2 -nanoparticle attachment that is size and aggregation dependent. Therefore, unproductive energy-transfer events between the selectively attached dyes can be prevented. In light of the latter, an efficiency improvement of 39 % has been achieved upon selective adsorption of benzoporphyrins and N719 onto different layers of TiO2 photoelectrode. PMID:27105771

  18. Dye-sensitized solar cell based carbon nanotube as counter electrode

    NASA Astrophysics Data System (ADS)

    Prasetio, Adi; Subagio, Agus; Purwanto, Agus; Widiyandari, Hendri

    2016-02-01

    The counter electrode using Carbon nanotube (CNT) has been successfully fabricated by the doctor blade method and their performances were investigated. We found that increasing mass of the CNT powder in binder increases electrocatalytic activity which this beneficial to conversion efficiency of the Dye-sensitized solar cell (DSSC). The photovoltaic performance of the DSSCs with 0.01, 0.02 and 0.04 gr of the CNT obtained overall conversion efficiencies of 0.32%, 0.74% and 0.91%, respectively. The results suggest that the CNT counter electrode has potential as alternative to the Pt free counter electrode for DSSC.

  19. Enhanced performance of dye-sensitized solar cells via plasmonic sandwiched structure

    NASA Astrophysics Data System (ADS)

    Lin, Su-Jien; Lee, Kuang-Che; Wu, Jyun-Lin; Wu, Jun-Yi

    2011-07-01

    The plasmonic structure of sandwiched TiO2/NPs-Ag/TiO2 electrodes was fabricated by sputter technology and sol-gel and spin coating procedure to enhance the performance of dye-sensitized solar cells. The improvement of the incident photon to photocurrent efficiency spectrum corresponding to the strong absorption and damping reflection indicated light trapping of plasmonic structure to elongate the optical pathways of photons. More light trapped close to photocurrent collecting electrode provides better charge-collection and light harvesting efficiencies. As a result of improved dye absorption, about 23% enhancement in photocurrent density has been achieved.

  20. Theoretical modeling of the series resistance effect on dye-sensitized solar cell performance

    NASA Astrophysics Data System (ADS)

    Huang, Yang; Dai, Songyuan; Chen, Shuanghong; Zhang, Changneng; Sui, Yifeng; Xiao, Shangfeng; Hu, Linhua

    2009-12-01

    Based on the continuity equations and the equivalent circuit, the conductivity of substrates and the resistances of silver grid in dye-sensitized solar cell (DSC) are investigated. The complete I-V characteristics of DSC are obtained with different internal resistances. The theoretical and experimental results show internal resistances dominate the fill factor of DSC. At the same time, DSC module is investigated by numerical simulation under parallel connection with different illumination intensities. It can be found the high resistivity of substrates and the high illumination intensity lead to a lower optimal width in the DSC module.

  1. Application of 3A molecular sieve layer in dye-sensitized solar cells

    SciTech Connect

    Yan, Yuan; Wang, Jinzhong E-mail: qingjiang.yu@hit.edu.cn; Yu, Qingjiang E-mail: qingjiang.yu@hit.edu.cn; Huang, Yuewu; Chang, Quanhong; Hao, Chunlei; Jiao, Shujie; Gao, Shiyong; Li, Hongtao; Wang, Dongbo

    2014-08-25

    3A molecular sieve layer was used as dehydration and electronic-insulation layer on the TiO{sub 2} electrode of dye-sensitized solar cells. This layer diminished the effect of water in electrolyte efficiently and enhanced the performance of cells. The conversion efficiency increased from 9.58% to 10.2%. The good moisture resistance of cells was attributed to the three-dimensional interconnecting structure of 3A molecular sieve with strong adsorption of water molecule. While the performance enhancement benefited from the suppression of the charge recombination of electronic-insulation layer and scattering effect of large particles.

  2. Nanographite-TiO2 photoanode for dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Sharma, S. S.; Sharma, Khushboo; Sharma, Vinay

    2016-05-01

    Nanographite-TiO2 (NG-TiO2) composite was successfully synthesized by the hydrothermal method and its performance as the photoanode for dye-sensitized solar cells (DSSCs) was investigated. Environmental Scanning electron microscope (E-SEM) micrographs show the uniform distribution of TiO2 nanoflowers deposited over nanographite sheets. The average performance characteristics of the assembled cell in terms of short-ciruit current density (JSC), open circuit voltage (VOC), fill factor (FF) and photoelectric conversion efficiency (η) were measured.

  3. Ultrafast Fabrication of Flexible Dye-Sensitized Solar Cells by Ultrasonic Spray-Coating Technology

    PubMed Central

    Han, Hyun-Gyu; Weerasinghe, Hashitha C.; Min Kim, Kwang; Soo Kim, Jeong; Cheng, Yi-Bing; Jones, David J.; Holmes, Andrew B.; Kwon, Tae-Hyuk

    2015-01-01

    This study investigates novel deposition techniques for the preparation of TiO2 electrodes for use in flexible dye-sensitized solar cells. These proposed new methods, namely pre-dye-coating and codeposition ultrasonic spraying, eliminate the conventional need for time-consuming processes such as dye soaking and high-temperature sintering. Power conversion efficiencies of over 4.0% were achieved with electrodes prepared on flexible polymer substrates using this new deposition technology and N719 dye as a sensitizer. PMID:26420466

  4. Improved performance of dye-sensitized solar cells by tuning the properties of ruthenium complexes containing conjugated bipyridine ligands

    NASA Astrophysics Data System (ADS)

    Nguyen, Hong Minh; Nghia Nguyen, Duc; Kim, Nakjoong

    2010-06-01

    Three heteroleptic ruthenium complexes cis-[Ru(H2dcbpy)(L)(NCS)2], where H2dcbpy is 4,4'-dicarboxy-2,2'-bipyridine and L is 4-(4-(N,N-di-(p-anisyl)amino)styryl)-4'-methyl-2,2'-bipyridine (Dye-1), 4-(4-(N,N-di-(p-hexyloxyphenyl)amino)styryl)-4'-methyl-2,2'-bipyridine (Dye-2) or 4-(5-(N,N-di-(p-hexyloxyphenyl)-amino)-thiophene-2-yl-ethenyl)-4'-methyl-2,2'-bipyridine (Dye-3) have been synthesized and characterized. The influence of differently conjugated bipyridine ligands on these complexes was studied using UV-Vis spectroscopy and cyclic voltammetry. These heteroleptic complexes show appreciably broad absorption ranges and quite high extinction coefficients. These new dyes were used as photosensitizers in nanocrystalline TiO2 dye-sensitized solar cells. It was found that the difference in light-harvesting property between Dye-1, Dye-2 and Dye-3 is associated mainly with molar extinction coefficients and alignment of the HOMO–LUMO energy levels. The power conversion efficiencies of solar cells based on Dye-1 and Dye-2 are 4.21% and 4.41%, while Dye-3 delivered a lower efficiency of 2.88% under the same device fabrication and measurement conditions.

  5. Evaluation on over photocurrents measured from unmasked dye-sensitized solar cells

    SciTech Connect

    Lee, Gi-Won; Kim, Donghwan; Ko, Min Jae; Kim, Kyungkon; Park, Nam-Gyu

    2010-03-15

    We have investigated the change in photocurrent density (J{sub SC}) of dye-sensitized solar cell (DSSC) before and after covering an aperture mask on the cell, especially its dependence on solar absorption range in dye. Four different dyes having absorption threshold at 460 nm (P5), 520 nm (TA-St-CA), 680 nm (N719) and 820 nm (N749) are tested. J{sub SC} of the DSSC without mask decreases after mask, where the decreasing rate (triangle J{sub SC} = J{sub SC} (no mask) -J{sub SC} (with mask)/J{sub SC} (no mask)) becomes larger when dye absorption threshold decreases. triangle J{sub SC} at the given TiO{sub 2} film thickness of 10 {mu}m is determined to be about 20%, 15% and 13% for P5, TA-St-CA and N719-N749, respectively, which is reduced to 14% (TA-St-CA), 11.3% (N719) and 10.5% (N749) after increasing the thickness to 20 {mu}m, except for P5 dye remaining unchanged. According to the analysis based on IPCE and photon flux data, the over photocurrents observed for the unmasked dye-sensitized solar cells and their dependence on dye absorption range are found to be attributed to diffuse light leaving the dye-adsorbed TiO{sub 2} active area. (author)

  6. Near-infrared squaraine co-sensitizer for high-efficiency dye-sensitized solar cells.

    PubMed

    Rao, G Hanumantha; Venkateswararao, A; Giribabu, L; Han, Liyuan; Bedja, Idriss; Gupta, Ravindra Kumar; Islam, Ashraful; Singh, Surya Prakash

    2016-06-01

    A combination of squaraine-based dyes (SPSQ1 and SPSQ2) and a ruthenium-based dye (N3) were chosen as co-sensitizers to construct efficient dye-sensitized solar cells. The co-sensitization of squaraine dyes with N3 enhanced their light-harvesting properties as a result of the broad spectral coverage in the region 350-800 nm. The co-sensitized solar cells based on SPSQ2 + N3 showed the highest short circuit current density of 17.10 mA cm(-2), an open circuit voltage of 0.66 V and a fill factor of 0.73, resulting in the highest power conversion efficiency of 8.2%, which is higher than that of the dye-sensitized solar cells based on the individual SPSQ1 and SPSQ2 dyes. The high power conversion efficiency of SPSQ2 + N3 was ascribed to its good light-harvesting properties, which resulted from its broader incident photon current conversion spectrum than that of the individual dyes. The high electron life time and electron recombination, which were the main causes of the higher efficiency of the device, were successfully analysed and correlated using transient absorption spectrometry and intensity-modulated photovoltage spectrometry. PMID:27167491

  7. Effect of photoanode thickness on electrochemical performance of dye sensitized solar cell

    NASA Astrophysics Data System (ADS)

    Khatani, Mehboob; Mohamed, Norani Muti; Hamid, Nor Hisham; Muhsan, Ali Samer; Sahmer, Ahmed Zahrin

    2015-07-01

    The thickness of photoanode is crucial as it adsorbed a large amount of dye molecules that provide electrons for generation of electricity in dye sensitized solar cell (DSC). Thus, in order to realize the practical application of DSC, study on various thickness of photoanode need to be carried out to analyze its effect on the electrochemical behavior of dye sensitized solar cell. To enhance the conversion efficiency, an additional layer of TiO2 using TiCl4 treatment was deposited prior to the deposition of the photoanode (active area of 1cm2) with the thickness of 6, 12, 18, 24, and 30 µm on fluorine doped tin oxide (FTO) glass substrate. The resulting photoanode after the soak in N719 dye for more than 12hrs were used to be assembled in a test cell in combination with liquid electrolyte and counter electrode. The fabricated cells were characterized by solar simulator, ultraviolet-visible spectroscopy (UV-VIS), and electrochemical impedance spectroscopy (EIS). Scanning electron microscopy (SEM) was used to approximate the thickness of photoanode. An optimum power conversion efficiency of 4.54% was obtained for the cell fabricated with 18 µm photoanode thickness. This is attributed to the reduced resistance related to electron transport in the TiO2/dye/electrolyte interface as proven by the EIS result. This led to the reduction of internal resistance, the increase in the electron life time and the improvement in the conversion efficiency.

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

    SciTech Connect

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

    2010-03-15

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

  9. Large pi-aromatic molecules as potential sensitizers for highly efficient dye-sensitized solar cells.

    PubMed

    Imahori, Hiroshi; Umeyama, Tomokazu; Ito, Seigo

    2009-11-17

    Recently, dye-sensitized solar cells have attracted much attention relevant to global environmental issues. Thus far, ruthenium(II) bipyridyl complexes have proven to be the most efficient TiO(2) sensitizers in dye-sensitized solar cells. However, a gradual increment in the highest power conversion efficiency has been recognized in the past decade. More importantly, considering that ruthenium is a rare metal, novel dyes without metal or using inexpensive metal are desirable for highly efficient dye-sensitized solar cells. Large pi-aromatic molecules, such as porphyrins, phthalocyanines, and perylenes, are important classes of potential sensitizers for highly efficient dye-sensitized solar cells, owing to their photostability and high light-harvesting capabilities that can allow applications in thinner, low-cost dye-sensitized solar cells. Porphyrins possess an intense Soret band at 400 nm and moderate Q bands at 600 nm. Nevertheless, the poor light-harvesting properties relative to the ruthenium complexes have limited the cell performance of porphyrin-sensitized TiO(2) cells. Elongation of the pi conjugation and loss of symmetry in porphyrins cause broadening and a red shift of the absorption bands together with an increasing intensity of the Q bands relative to that of the Soret band. On the basis of the strategy, the cell performance of porphyrin-sensitized solar cells has been improved intensively by the enhanced light absorption. Actually, some push-pull-type porphyrins have disclosed a remarkably high power conversion efficiency (6-7%) that was close to that of the ruthenium complexes. Phthalocyanines exhibit strong absorption around 300 and 700 nm and redox features that are similar to porphyrins. Moreover, phthalocyanines are transparent over a large region of the visible spectrum, thereby enabling the possibility of using them as "photovoltaic windows". However, the cell performance was poor, owing to strong aggregation and lack of directionality in the

  10. Photostability of low cost dye-sensitized solar cells based on natural and synthetic dyes

    NASA Astrophysics Data System (ADS)

    Abdou, E. M.; Hafez, H. S.; Bakir, E.; Abdel-Mottaleb, M. S. A.

    2013-11-01

    This paper deals with the use of some natural pigments as well as synthetic dyes to act as sensitizers in dye-sensitized solar cells (DSSCs). Anthocyanin dye extracted from rosella (Hibiscus sabdariffa L.) flowers, the commercially available textile dye Remazole Red RB-133 (RR) and merocyanin-like dye based on 7-methyl coumarin are tested. The photostability of the three dyes is investigated under UV-Vis light exposure. The results show a relatively high stability of the three dyes. Moreover, the photostability of the solid dyes is studied over the TiO2 film electrodes. A very low decolorization rates are recorded as; rate constants k = 1.6, 2.1 and 1.9 × 10-3 min-1 for anthocyanin, RR and coumarin dyes, respectively. The stability results favor selecting anthocyanin as a promising sensitizer candidate in DSSCs based on natural products. Dyes-sensitized solar cells are fabricated and their conversion efficiency (η) is 0.27%, 0.14% and 0.001% for the anthocyanin, RR and coumarin dyes, respectively. Moreover, stability tests of the sealed cells based on anthocyanin and RR dyes are done under continuous light exposure of 100 mW cm-2, reveals highly stable DSSCs.

  11. Hydrothermally growth of novel hierarchical structures titanium dioxide for high efficiency dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Cheng, Pengfei; Liu, Yang; Sun, Peng; Du, Sisi; Cai, Yaxin; Liu, Fengmin; Zheng, Jie; Lu, Geyu

    2014-12-01

    We report an innovative development of novel double layered photoanodes made of hierarchical TiO2 micro-corollas as the overlayer and TiO2 nanoforest as the underlayer (HTCF), for dye-sensitized solar cells (DSSCs). They are obtained by a facile hydrothermal reaction of TiO2 nanorods array with top microspheres (MS)/FTO (Fluorine-doped tin oxide) glass substrate in an alkaline solution. In this process, the microspheres and nanorods are transformed into micro-corollas and nanotrees, respectively. The photoanodes with HTCF structure can greatly improve the light scattering ability due to their novel structures. Moreover, the enhanced surface area of HTCF can lead to larger dye loading, which achieves the higher light harvesting capacity. Base on the fast electron transport of the interior nanorods, higher light scattering and harvesting capacities, this novel HTCF photoanode realizes tri-functions. The overall power conversion efficiency (PCE) of the HTCF DSSCs are 51% increase in the conversion efficiency compare with those of constructed by bare TiO2 nanorod arrays. In our work, tri-functions of photoanodes are obtained by improving the 1D TiO2 nanostructures (nanorod, nanowire, nanotube et al.). To the best of our knowledge, it is a significant fabrication technology breakthrough for the photoanode of dye-sensitized solar cells.

  12. Monitoring the dye impregnation time of nanostructured photoanodes for dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Shahzad, N.; Pugliese, D.; Lamberti, A.; Sacco, A.; Virga, A.; Gazia, R.; Bianco, S.; Shahzad, M. I.; Tresso, E.; Pirri, C. F.

    2013-06-01

    Dye-sensitized solar cells (DSSCs) are getting increasing attention as low-cost, easy-to-prepare and colored photovoltaic devices. In the current work, in view of optimizing the fabrication procedures and understanding the mechanisms of dye attachment to the semiconductor photoanode, absorbance measurements have been performed at different dye impregnation times ranging from few minutes to 24 hours using UV-Vis spectroscopy. In addition to the traditional absorbance experiments, based on diffuse and specular reflectance on dye impregnated thin films and on the desorption of dye molecules from the photoanodes by means of a basic solution, an alternative in-situ solution depletion measurement, which enables fast and continuous evaluation of dye uptake, is presented. Photoanodes have been prepared with two different nanostructured semiconducting films: mesoporous TiO2, using a commercially available paste from Solaronix, and sponge-like ZnO obtained in our laboratory from sputtering and thermal annealing. Two different dyes have been analyzed: Ruthenizer 535-bisTBA (N719), which is widely used because it gives optimal photovoltaic performances, and a new metal-free organic dye based on a hemisquaraine molecule (CT1). Dye sensitized cells were fabricated using a customized microfluidic architecture. The results of absorbance measurements are presented and discussed in relation to the obtained solar energy conversion efficiencies and the incident photon-to-electron conversion efficiencies (IPCE).

  13. Graphene assistance enhanced dye-sensitized solar cell performance of tin sulfide microspheres

    NASA Astrophysics Data System (ADS)

    Yang, Bo; Chen, Peng; Zuo, Xueqin; Zhou, Lei; Yang, Xiao; Li, Guang; Wu, Mingzai; Ma, Yongqing; Jin, Shaowei; Zhu, Kerong

    2015-10-01

    In this work, the nanosheet-assembled SnS2 microspheres were synthesized through a solvothermal method, and the catalytic activities of the microspheres were investigated by J-V and power conversion efficiency tests as counter electrodes in dye-sensitized solar cells. The cell showed an energy conversion efficiency up to 6.4%. To further improve the power conversion efficiency of the counter electrode of the microspheres, different amounts of reduced graphene were added into the microspheres by simply physical mixing. With the addition of 6 wt% reduced graphene, the short-circuit current density, open-circuit voltage and fill factor were 15.18 mA cm-2, 775 mV, and 63.4%, respectively. More important, the conversion efficiency reached 7.46%, which is approximately 17% higher than that of the cell with pure SnS2 microspheres as counter electrode. Compared to conventional materials used in dye-sensitized solar cells, SnS2 microspheres have the advantages of facile synthesis, low-cost and high efficiency with graphene assistance.

  14. Conformal growth of anodic nanotubes for dye-sensitized solar cells: part II. Nonplanar electrode.

    PubMed

    Sun, Lidong; Zhang, Sam; Wang, Qing

    2014-02-01

    Anodic titania nanotube array features highly ordered alignment as well as porous nature, and exhibits intriguing properties when employed in a variety of applications. All these profit from the continuous efforts on controlling the nanotube configurations. Recently, nonplanar electrodes have also been used to grow the nanotubes besides the conventional planar counterparts. As such, it is of great interest and significance to complete a picture to link the nanotubes grown on planar and various nonplanar electrodes for a comprehensive understanding of nanotube growing manners, in an attempt to boost their future applications. In the first part of this review, planar electrodes are focused with regard to nanotube growth and application in dye-sensitized solar cells. In this part, the nanotubes grown on patterned or curved surfaces are discussed first with reference to a similar structure of alumina nanopores, which are subsequently used to mirror the growth of nanotubes on cylindrical electrodes (i.e., titanium wires or meshes). The last section focuses on titanium tubular electrodes which are attractive for thermal fluids in view of the drastically reduced thermal conductivity in the presence of anodic nanotubes. As a recent hot topic, wire-shaped dye-sensitized solar cells are deliberated in terms of cell structure, efficiency calculation, merits, challenges and outlook. PMID:24749473

  15. Microstructure design of nanoporous TiO2 photoelectrodes for dye-sensitized solar cell modules.

    PubMed

    Hu, Linhua; Dai, Songyuan; Weng, Jian; Xiao, Shangfeng; Sui, Yifeng; Huang, Yang; Chen, Shuanghong; Kong, Fantai; Pan, Xu; Liang, Linyun; Wang, Kongjia

    2007-01-18

    The optimization of dye-sensitized solar cells, especially the design of nanoporous TiO2 film microstructure, is an urgent problem for high efficiency and future commercial applications. However, up to now, little attention has been focused on the design of nanoporous TiO2 microstructure for a high efficiency of dye-sensitized solar cell modules. The optimization and design of TiO2 photoelectrode microstructure are discussed in this paper. TiO2 photoelectrodes with three different layers, including layers of small pore size films, larger pore size films, and light-scattering particles on the conducting glass with the desirable thickness, were designed and investigated. Moreover, the photovoltaic properties showed that the different porosities, pore size distribution, and BET surface area of each layer have a dramatic influence on short-circuit current, open-circuit voltage, and fill factor of the modules. The optimization and design of TiO2 photoelectrode microstructure contribute a high efficiency of DSC modules. The photoelectric conversion efficiency around 6% with 15 x 20 cm2 modules under illumination of simulated AM1.5 sunlight (100 mW/cm2) and 40 x 60 cm2 panels with the same performance tested outdoor have been achieved by our group. PMID:17214486

  16. Photostability of low cost dye-sensitized solar cells based on natural and synthetic dyes.

    PubMed

    Abdou, E M; Hafez, H S; Bakir, E; Abdel-Mottaleb, M S A

    2013-11-01

    This paper deals with the use of some natural pigments as well as synthetic dyes to act as sensitizers in dye-sensitized solar cells (DSSCs). Anthocyanin dye extracted from rosella (Hibiscus sabdariffa L.) flowers, the commercially available textile dye Remazole Red RB-133 (RR) and merocyanin-like dye based on 7-methyl coumarin are tested. The photostability of the three dyes is investigated under UV-Vis light exposure. The results show a relatively high stability of the three dyes. Moreover, the photostability of the solid dyes is studied over the TiO2 film electrodes. A very low decolorization rates are recorded as; rate constants k=1.6, 2.1 and 1.9×10(-3)min(-1) for anthocyanin, RR and coumarin dyes, respectively. The stability results favor selecting anthocyanin as a promising sensitizer candidate in DSSCs based on natural products. Dyes-sensitized solar cells are fabricated and their conversion efficiency (η) is 0.27%, 0.14% and 0.001% for the anthocyanin, RR and coumarin dyes, respectively. Moreover, stability tests of the sealed cells based on anthocyanin and RR dyes are done under continuous light exposure of 100mWcm(-2), reveals highly stable DSSCs. PMID:23832227

  17. Optimizations of quasi-solid-state dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Biancardo, Matteo; West, Keld; Krebs, Frederik C.

    2005-10-01

    In this paper we report on an attempt to substitute the liquid-electrolyte in Dye Sensitized Solar Cells (LC) by quasi-solid-state constructions (SC) adopting organic/inorganic gels as well as a novel dye comprised of a conjugated polymer covalently linked to a ruthenium complex that can be bound to a TiO2 anatase electrode. Gel polymer electrolytes are prepared by incorporating liquid electrolytes into a polymer matrix such as poly methyl methacrylate (PMMA) using a gelling solvent such as propylene carbonate (PC). Dye Sensitized Solar Cell (DSSC) fabricated using the former gel electrolytes and standard sensitizing dye such as cis-bis(thiocyano) ruthenium(II)-bis-2,2'-bipyridine-4,4'-dicarboxylate (N3) exhibit an encouraging short circuit current densitie (Jsc) of 4.45 mA cm-2 with open circuit voltages (Voc) of 495 mV. In the novel dye the conjugated polymer provides light harvesting and hole conduction while the ruthenium complex binds to the anatase electrode providing efficient charge carrier separation and injection into the anatase electrode.

  18. A critical review of recent developments in nanomaterials for photoelectrodes in dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Raj, C. Clement; Prasanth, R.

    2016-06-01

    In a dye sensitized solar cell the photoanode performs a dual role of acting as a matrix for dye adsorption and as a charge transport medium for electron transport. The surface area and the electronic property of the material determine the current output of the device. So the performance of dye sensitized solar cell is significantly affected by our choice of material to be used as photoanode. High surface area, optimum carrier density, low impedance and efficient carrier transport are requirements for an efficient photoanode material in a DSSC. The goal of this review article is to highlight the fabrication methods used for the preparation of efficient nanostructured photoanodes. The application of these nanostructured photoanode materials and their impact on the device efficiency has been described in detail. The enhancement in the surface area of the material and its impact on the dye adsorption and current generation has been discussed. A detailed analysis of the role of different blocking layers used in improving the open circuit voltage of the device has been done. The outlook and future directions in improving the device performance are also discussed.

  19. High-efficiency dye-sensitized solar cells using ferrocene-based electrolytes and natural photosensitizers

    NASA Astrophysics Data System (ADS)

    Sönmezoğlu, Savaş; Akyürek, Cafer; Akin, Seçkin

    2012-10-01

    A new and promising dye-sensitized solar cell (DSSC) bilayer design was developed using an Fe2+/Fe3+ (ferrocene) liquid electrolyte and natural dyes extracted from Hypericum perforatum, Rubia tinctorum L. and Reseda luteola. The photovoltaic parameters controlling the device performance were then investigated. A DSSC based on quercetin dye displayed the most efficient solar to electricity conversion efficiency compared with other dyes with a maximum η value of 2.17%. Maximum overall conversion efficiencies under simulated sunlight that was comparable to natural photosynthesis were increased by 15%. The identification of appropriate additives for improving VOC without causing dye degradation may result in further enhancement of cell performance, making the practical application of such systems more suitable for achieving economically viable solar energy devices.

  20. Efficient Dye-Sensitized Solar Cells Using Red Turnip and Purple Wild Sicilian Prickly Pear Fruits

    PubMed Central

    Calogero, Giuseppe; Di Marco, Gaetano; Cazzanti, Silvia; Caramori, Stefano; Argazzi, Roberto; Di Carlo, Aldo; Bignozzi, Carlo Alberto

    2010-01-01

    Dye-sensitized solar cells (DSSCs) were assembled by using the bougainvillea flowers, red turnip and the purple wild Sicilian prickly pear fruit juice extracts as natural sensitizers of TiO2 films. The yellow orange indicaxanthin and the red purple betacyanins are the main components in the cocktail of natural dyes obtained from these natural products. The best overall solar energy conversion efficiency of 1.7% was obtained, under AM 1.5 irradiation, with the red turnip extract, that showed a remarkable current density (Jsc = 9.5 mA/cm2) and a high IPCE value (65% at λ = 470 nm). Also the purple extract of the wild Sicilian prickly pear fruit showed interesting performances, with a Jsc of 9.4 mA/cm2, corresponding to a solar to electrical power conversion of 1.26%. PMID:20162014

  1. Methods of Measuring Energy Conversion Efficiency in Dye-sensitized Solar Cells

    NASA Astrophysics Data System (ADS)

    Koide, Naoki; Chiba, Yasuo; Han, Liyuan

    2005-06-01

    The current-voltage characteristics of dye-sensitized solar cells (DSCs) were measured and compared with those of crystalline silicon solar cells. It was found that the energy conversion efficiency of DSCs is dependent on voltage sweep direction and sampling delay time (Td). Measurement of the transient photocurrent revealed that this dependence is due to the longer time constant of DSCs. This dependence was also confirmed in a simulation of current-voltage curves based on an equivalent circuit model of DSCs. Analysis of the current-voltage characteristics of polymer-based bulk heterojunction solar cells (BHSCs) and simulated measurements showed that the longer time constant is due to slow movement of ions in the electrolyte. To improve accuracy, the I-V measurement should be carried out from short circuit to open circuit with Td of 100 ms or longer.

  2. Spectral splitting photovoltaics using perovskite and wideband dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Kinoshita, Takumi; Nonomura, Kazuteru; Joong Jeon, Nam; Giordano, Fabrizio; Abate, Antonio; Uchida, Satoshi; Kubo, Takaya; Seok, Sang Il; Nazeeruddin, Mohammad Khaja; Hagfeldt, Anders; Grätzel, Michael; Segawa, Hiroshi

    2015-11-01

    The extension of the light absorption of photovoltaics into the near-infrared region is important to increase the energy conversion efficiency. Although the progress of the lead halide perovskite solar cells is remarkable, and high conversion efficiency of >20% has been reached, their absorption limit on the long-wavelength side is ~800 nm. To further enhance the conversion efficiency of perovskite-based photovoltaics, a hybridized system with near-infrared photovoltaics is a useful approach. Here we report a panchromatic sensitizer, coded DX3, that exhibits a broad response into the near-infrared, up to ~1100 nm, and a photocurrent density exceeding 30 mA cm-2 in simulated air mass 1.5 standard solar radiation. Using the DX3-based dye-sensitized solar cell in conjunction with a perovskite cell that harvests visible light, the hybridized mesoscopic photovoltaics achieved a conversion efficiency of 21.5% using a system of spectral splitting.

  3. The effect of TiCl4 treatment on the efficiency of dye sensitized solar cell

    NASA Astrophysics Data System (ADS)

    Ardakani, Seyed Esmaeil Mahdavi; Singh, Balbir Singh Mahinder; Mohammed, Norani Muti

    2014-10-01

    Dye sensitized solar cells (DSSC) are the new generation of solar cells that have their advantages such as transparency, flexibility and low cost production. This has certainly attracted researchers in the field of green technology to further develop DSSC. The focus is on the efficiency, as it is low at this point of time, as compared to silicon based solar cells. In this paper, the effect of TiCl4 treatment on the efficiency of DSSC by treating the conducting glass and TiO2 layer was studied and results showed that the TiCl4 treatment on the conducting glass and the printed TiO2 film increased the efficiency from 3.45% to 4.43%. The TiO2 layer was characterized by using FESEM and AFM and the efficiency of the DSSC was measured by using the sunlight simulator.

  4. Transient 2D IR spectroscopy of charge injection in dye-sensitized nanocrystalline thin films.

    PubMed

    Xiong, Wei; Laaser, Jennifer E; Paoprasert, Peerasak; Franking, Ryan A; Hamers, Robert J; Gopalan, Padma; Zanni, Martin T

    2009-12-23

    We use nonlinear 2D IR spectroscopy to study TiO(2) nanocrystalline thin films sensitized with a Re dye. We find that the free electron signal, which often obscures the vibrational features in the transient absorption spectrum, is not observed in the 2D IR spectra. Its absence allows the vibrational features of the dye to be much better resolved than with the typical IR absorption probe. We observe multiple absorption bands but no cross peaks in the 2D IR spectra, which indicates that the dyes have at least three conformations. Furthermore, by using a pulse sequence in which we initiate electron transfer in the middle of the infrared pulse train, we are able to assign the excited state features by correlating them to the ground state vibrational modes and determine that the three conformations have different time scales and cross sections for electron injection. 2D IR spectroscopy is proving to be very useful in disentangling overlapping structural distributions in biological and chemical physics processes. These experiments demonstrate that nonlinear infrared probes are also a powerful new tool for studying charge transfer at interfaces. PMID:19947603

  5. Solvent dipole modulation of conduction band edge shift and charge recombination in robust dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Hao, Feng; Jiao, Xingjian; Li, Jianbao; Lin, Hong

    2012-12-01

    Molecular modification is certified as a powerful strategy to adjust the energy alignment and electron transfer dynamics of dye-sensitized solar cells (DSCs). Herein, devices are assembled with three robust solvent (3-methoxypropionitrile, N,N-dimethylformamide and γ-butyrolactone) based electrolytes to elucidate the solvent dipole effects at the semiconductor-dye-electrolyte interface. Photovoltaic results demonstrate that open-circuit photovoltages of the devices vary linearly with the dipole moment of the solvents, along with an adverse dependence of the short-circuit photocurrent density under simulated irradiation. Impedance analysis reveals an apparent dipole moment-modulated conduction band edge shift of the nanocrystalline TiO2 electrodes with respect to the redox potential of the electrolyte. Furthermore, the adverse shifts of the short-circuit photocurrent are explained by a dipole dependence of the driving force for electron injection and the interfacial charge recombination, together with a notably changed charge collection efficiency. Therefore, this study draws attention to the feasibility of tuning the electron transfer dynamics and energy alignment in photoelectrochemical devices by judiciously selecting the electrolyte solvents for further efficiency improvement, especially for those alternative organic sensitizers or quantum dots with inadequate electron injection driven forces.

  6. Nanostructured TiO2 films for dye-sensitized solar cells prepared by the sol-gel method.

    PubMed

    Jin, Young Sam; Kim, Kyung Hwan; Park, Sang Joon; Yoon, Hyon Hee; Choi, Hyung Wook

    2011-12-01

    TiO2 films were prepared on glass substrates using the sol-gel process for a dye-sensitized solar cell application. The TiO2 sol was prepared using hydrolysis/polycondensation. Titanium (IV) Tetra Isopropoxide (TTIP) was used as precursor and Nitric acid (HNO3) was used as a catalyst for the peptization. The crystal structure and morphology of the prepared materials were characterized by XRD, and an SEM. The observations confirmed the nanocrystalline nature of the TiO2. The reaction parameters, such as the catalyst concentrations, the calcination time, and the calcination temperature were varied during the synthesis in order to achieve nanosize TiO2 particles. The prepared TiO2 particles were coated onto FTO glass using a screen printing technique. The prepared TiO2 films were characterized by UV-vis. The TiO2 particles calcinated at low temperatures showed an anatase phase they grew into a rutile phase when the calcination temperature increased. The size and structure of the TiO2 particles were adjusted to specific surface areas. It was found that the conversion efficiency of the DSSC was highly affected by the properties of the TiO2 particles. PMID:22409037

  7. Enhanced corrosion resistance of TiN-coated stainless steels for the application in flexible dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Ouyang, Fan-Yi; Tai, Wei-Lun

    2013-07-01

    Metals foils have been increasingly used as alternative substrates for the flexible dye-sensitized solar cells (DSSCs) to overcome the limitations arising from the low sintering-temperature tolerance of the plastic substrates. However, the potential problem of metal corrosion in the iodide-based electrolytes threatens to degrade the performance and long-term stability of the metal-based DSSCs. To resolve this dilemma, we have employed unbalanced magnetron sputtering systems to prepare nanocrystalline TiN and TiN/Ti barriers, with the high packing factors of 0.7-0.8, on the metal substrates. The microstructure and properties of TiN and TiN/Ti barriers were characterized using SEM, XRD, AFM and SIMS. Their corrosion behaviors were evaluated through electrochemical impedance spectroscopy and potentiodynamic polarization in the simulated iodide-based electrolytes environment. The results show more than 78% improvement in reducing the corrosion current density by the deposition of the barrier. The charge transfer behavior occurring in the metal/electrolyte interface is also suppressed by the deposited barriers. Furthermore, because deposited barriers provide a larger surface area for dye adsorption and possess better corrosion protection, the barrier-deposited DSSCs have been demonstrated to attain 2.5 times higher energy conversion efficiency than uncoated DSSC.

  8. Efficiency enhancement in solid state dye sensitized solar cells by including inverse opals with controlled layer thicknesses

    NASA Astrophysics Data System (ADS)

    Zheng, Hanbin; Shah, Said Karim; Abbas, Mamatimin; Ly, Isabelle; Rivera, Thomas; Almeida, Rui M.; Hirsch, Lionel; Toupance, Thierry; Ravaine, Serge

    2016-09-01

    The photoconversion efficiency of dye sensitized solar cells can be enhanced by the incorporation of light management nanostructures such as photonic crystals. Here, we present a facile route to incorporate titania inverse opals into solid state dye sensitized solar cells and report photoconversion efficiency enhancements of up to 56% compared with a model system without the inverse opal. Our approach is based on the precise design of titania inverse opals with a predetermined thickness that can be controlled at the individual layer level. By choosing an inverse opal exhibiting a photonic bandgap which overlaps the absorption bands of the dye, our results show that there is an optimal thickness of the inverse opal structure for maximum efficiency enhancement of the cell. This is the first experimental proof that the thickness of a titania inverse opal plays a pivotal role in cell efficiency enhancement in solid state dye sensitized solar cells.

  9. Counter electrodes from conducting polymer intercalated graphene for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Li, Ru; Tang, Qunwei; Yu, Liangmin; Yan, Xuefeng; Zhang, Zhiming; Yang, Peizhi

    2016-03-01

    Creation of cost-effective and platinum-free counter electrodes (CEs) is persistent for developing advanced dye-sensitized solar cells (DSSCs). We present here the fabrication of conducting polymers such as polyaniline (PANi), polypyrole (PPy), or poly(3,4-ethylenedioxythiophene) (PEDOT) intercalated reduced graphene oxide (rGO) CEs on flexible Ti foil or polyethylene-terephthalate substrate for liquid-junction DSSC applications. The ration architecture integrates the high electron-conducting ability of graphene and good electrocatalytic activity of a conducting polymer into a single CE material. The preliminary results demonstrate that the resultant CEs follow an order of rGO/PPy > rGO/PANi > rGO/PEDOT > rGO. A maximal cell efficiency of 6.23% is determined on the optimized solar cell device, yielding 104.9% enhancement in comparison to rGO based device.

  10. Smart photovoltaics based on dye-sensitized solar cells using photochromic spiropyran derivatives as photosensitizers

    NASA Astrophysics Data System (ADS)

    Ma, Shengbo; Ting, Hungkit; Ma, Yingzhuang; Zheng, Lingling; Zhang, Miwei; Xiao, Lixin; Chen, Zhijian

    2015-05-01

    In this paper, smart photovoltaic (SPV) devices, integrating both functions of solar cells and smart windows, was fabricated based on dye-sensitized solar cells using photochromic spiropyran derivatives SIBT as photosensitizers. SPV devices have self-regulated power conversion efficiency (PCE) and light transmission responding to the incident spectra due to the photoisomerization of SIBT. SIBT isomerize from closed-ring form to open-ring form under UV illumination, accompanied with enhanced visible light absorption and electron delocalization. Therefore, increased PCE and absorption in SPV devices were observed under UV treatment and the devices can be restored gradually to the initial status when kept in dark. The SPV devices have self-regulation of PCE and sunlight transmission responding to the changing sun spectra in different times of a day, providing a proper energy usage and a better sun-shading.

  11. Influence of capacitance characteristic on dye-sensitized solar cell's IPCE measurement

    NASA Astrophysics Data System (ADS)

    Tian, Hanmin; Liu, Lifei; Liu, Bin; Kui Yuan, Shi; Wang, Xiangyan; Wang, Ying; Yu, Tao; Zou, Zhigang

    2009-02-01

    It is found that the traditional monochromatic incident photon-to-electron conversion efficiency (IPCE) measurement method, such as the American Society for Testing and Materials standard (ASTM), is not suitable for measuring the IPCE of dye-sensitized solar cells (DSSCs). Experiments showed that the chopper's frequency in this method influences the measured DSSCs' IPCE value considerably, while no such impact was found in that of the Si cell. The quantitative analysis, which is based on equivalent circuits and parameter estimation, proved the existence of capacitance characteristics in DSSCs causing the fluctuation of the measured IPCE. An equivalent circuit parameter was estimated from a typical dye solar cell, which was characterized with the crystalline ingredient, the particle size and the I-V curve. The fluctuations of the measured IPCE were revealed by adjusting the chopper frequencies of one traditional IPCE measurement system. Finally, the method to obtain the real value of DSSCs' IPCE is proposed.

  12. Vanadium oxide (VO) based low cost counter electrode in dye sensitized solar cell (DSSC) applications

    SciTech Connect

    Vijayakumar, P.; Pandian, Muthu Senthil; Ramasamy, P.

    2015-06-24

    Vanadium oxide nanostars were synthesized by chemical method. The prepared Vanadium oxide nanostars are introduced into dye sensitized solar cell (DSSC) as counter electrode (CE) catalyst to replace the expensive platinum (Pt). The products were characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM), and Brunauer–Emmett–Teller (BET) method. The photovoltaic performance of the VO as counter electrode based DSSC was evaluated under simulated standard global AM 1.5G sunlight (100 mW/cm{sup 2}). The solar to electrical energy conversion efficiency (η) of the DSSC was found to be 0.38%.This work expands the Counter electrode catalyst, which can help to reduce the cost of DSSC and thereby encourage their fundamental research and commercial application.

  13. Bifacial dye-sensitized solar cells based on vertically oriented TiO2 nanotube arrays

    NASA Astrophysics Data System (ADS)

    Liu, Zhaoyue; Misra, Mano

    2010-03-01

    In this work we describe a novel bifacial design concept for dye-sensitized solar cells (DSCs). Bifacial DSCs are fabricated with ruthenium complex chemisorbed double-sided TiO2 nanotube arrays on a Ti metal substrate, in combination with two electron-collecting counter electrodes. Our investigation shows that the present bifacial DSCs have similar conversion efficiencies when illuminated from either their front or rear side, and a summated output power when illuminated on both sides. Furthermore, this type of bifacial DSC is also able to summate the output power of each side when working at an 'unsymmetrical' mode, in which much different output powers are generated by the front and rear sides. Therefore, this bifacial design concept exhibits a promising potential to reduce the cost of solar electricity when DSCs are operated at a location where a high albedo radiation is available.

  14. Critical analysis on degradation mechanism of dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Mohamad Shahimin, Mukhzeer; Suhaimi, Suriati; Abd Wahid, Mohd Halim; Retnasamy, Vithyacharan; Ahmad Hambali, Nor Azura Malini; Reshak, Ali Hussain

    2015-09-01

    This paper reports on a précis of degradation mechanism for dye-sensitized solar cell (DSSCs). The review indicates progress in the understanding of degradation mechanism, in particular, the large improvement in the analysis of the materials used in DSSCs. The paper discussed on the stability issues of the dye, advancement of the photoelectrode film lifetime, changes in the electrolyte components and degradation analysis of the counter electrode. The photoelectrochemical parameters were evaluated in view of the possible degradation routes via open circuit voltage (Voc), short circuit current (Isc), fill factor (FF) and overall conversion efficiency (η) from the current-voltage curve. This analysis covers several types of materials that have paved the way for better-performing solar cells and directly influenced the stability and reliability of DSSCs. The new research trend together with the previous research has been highlighted to examine the key challenges faced in developing the ultimate DSSCs.

  15. Gold nanoparticle decorated multi-walled carbon nanotubes as counter electrode for dye sensitized solar cells.

    PubMed

    Kaniyoor, Adarsh; Ramaprabhu, Sundara

    2012-11-01

    A novel counter electrode material for dye sensitized solar cells (DSSCs) composed of nanostructured Au particles decorated on functionalized multi-walled carbon nanotubes (f-MWNTs) is demonstrated for the first time. MWNTs synthesized by catalytic chemical vapor deposition technique are purified and functionalized by treating with concentrated acids. Au nanoparticles are decorated on f-MWNTs by a rapid and facile microwave assisted polyol reduction method. The materials are characterized by X-ray diffractometry, Fourier transform infra red spectroscopy and electron microscopy. The DSSC fabricated with Au/f-MWNTs based counter electrode shows enhanced power conversion efficiency (eta) of 4.9% under AM 1.5G simulated solar radiation. In comparison, the reference DSSCs fabricated with f-MWNTs and Pt counter electrodes show eta of 2.1% and 4.5%. This high performance of Au/f-MWNTs counter electrode is investigated using electrochemical impedance spectroscopy and cyclic voltammetry studies. PMID:23421212

  16. Dye-sensitized solar cells based on different nano-oxides on plastic PET substrate

    NASA Astrophysics Data System (ADS)

    Mikula, Milan; Gemeiner, Pavol; Beková, Zuzana; Dvonka, Vladimír; Búc, Dalibor

    2015-01-01

    Polyethylene-terephthalate (PET) foils and glass slides coated with thin conductive layers were used as substrates for TiO2 or ZnO based photoactive electrodes of dye-sensitized solar cells (DSSC) with organo-metallic Ru-dye, standard iodine electrolyte and Pt coated FTO/glass counterelectrode (CE). Different compositions of nanoparticle oxides in forms of alcohol pastes as well as the CE paste were applied onto the substrates by screen printing or by doctor blade techniques. Photocurrents and I-V loading characteristics were measured depending on the solar cell structure and preparation, including the oxide composition, electrode conductivity and the dye type. The influence of thin TiO2 blocking layer prepared by sol-gel technique is also discussed.

  17. Dye-sensitized solar cells with natural dyes extracted from plant seeds

    NASA Astrophysics Data System (ADS)

    El-Ghamri, Hatem S.; El-Agez, Taher M.; Taya, Sofyan A.; Abdel-Latif, Monzir S.; Batniji, Amal Y.

    2014-12-01

    The application of natural dyes extracted from plant seeds in the fabrication of dye-sensitized solar cells (DSSCs) has been explored. Ten dyes were extracted from different plant seeds and used as sensitizers for DSSCs. The dyes were characterized using UV-Vis spectrophotometry. DSSCs were prepared using TiO2 and ZnO nanostructured mesoporous films. The highest conversion efficiency of 0.875 % was obtained with an allium cepa (onion) extract-sensitized TiO2 solar cell. The process of TiO2-film sintering was studied and it was found that the sintering procedure significantly affects the response of the cell. The short circuit current of the DSSC was found to be considerably enhanced when the TiO2 semiconducting layer was sintered gradually.

  18. Dye-sensitized solar cells using double-oxide electrodes: a brief review

    NASA Astrophysics Data System (ADS)

    Suzuki, Yoshikazu; Okamoto, Yuji; Ishii, Natsumi

    2015-04-01

    Dye-sensitized solar cells (DSC or DSSC) have been widely investigated because of their potentially high cost performance compared with Si-based solar cells and of their fascinating appearance. DSC with photoelectric conversion efficiency of >10 % (or even 12 %) have been reported, where porous TiO2 films are generally used as semi-conductor electrodes. Such porous TiO2 films usually have high specific surface area, and thus, they adsorb plenty of dye molecules, resulting in high photocurrent density. Recently, some double oxides have been examined as alternative photoanode materials, mainly in order to improve photovoltage. Here, studies on DSC using double-oxide electrodes, i.e., perovskite, spinel, ilmenite, wolframite, scheelite and pseudobrookite-types, are briefly reviewed.

  19. Electrochemically Reduced Graphene Oxide Multilayer Films as Efficient Counter Electrode for Dye-Sensitized Solar Cells

    PubMed Central

    Xu, Xiaobao; Huang, Dekang; Cao, Kun; Wang, Mingkui; Zakeeruddin, Shaik M.; Grätzel, Michael

    2013-01-01

    We report on a new counter electrode for dye-sensitized solar cells (DSCs), which is prepared using layer-by-layer assembly of negatively charged graphene oxide and positively charged poly (diallyldimethylammonium chloride) followed by an electrochemical reduction procedure. The DSC devises using the heteroleptic Ru complex C106TBA as sensitizer and this new counter electrode reach power conversion efficiencies of 9.5% and 7.6% in conjunction with low volatility and solvent free ionic liquid electrolytes, respectively. The new counter electrode exhibits good durability (60°C for 1000 h in a solar simulator, 100 mW cm−2) during the accelerated tests when used in combination with an ionic liquid electrolyte. This work identifies a new class of electro-catalysts with potential for low cost photovoltaic devices. PMID:23508212

  20. Bifacial dye-sensitized solar cells based on vertically oriented TiO2 nanotube arrays.

    PubMed

    Liu, Zhaoyue; Misra, Mano

    2010-03-26

    In this work we describe a novel bifacial design concept for dye-sensitized solar cells (DSCs). Bifacial DSCs are fabricated with ruthenium complex chemisorbed double-sided TiO(2) nanotube arrays on a Ti metal substrate, in combination with two electron-collecting counter electrodes. Our investigation shows that the present bifacial DSCs have similar conversion efficiencies when illuminated from either their front or rear side, and a summated output power when illuminated on both sides. Furthermore, this type of bifacial DSC is also able to summate the output power of each side when working at an 'unsymmetrical' mode, in which much different output powers are generated by the front and rear sides. Therefore, this bifacial design concept exhibits a promising potential to reduce the cost of solar electricity when DSCs are operated at a location where a high albedo radiation is available. PMID:20195012

  1. Bifacial dye-sensitized solar cells based on an ionic liquid electrolyte

    NASA Astrophysics Data System (ADS)

    Ito, Seigo; Zakeeruddin, Shaik M.; Comte, Pascal; Liska, Paul; Kuang, Daibin; Grätzel, Michael

    2008-11-01

    Solar energy is a promising solution to global energy-related problems because it is clean, inexhaustible and readily available. However, the deployment of conventional photovoltaic cells based on silicon is still limited by cost, so alternative, more cost-effective approaches are sought. Here we report a bifacial dye-sensitized solar cell structure that provides high photo-energy conversion efficiency (~6%) for incident light striking its front or rear surfaces. The design comprises a highly stable ruthenium dye (Z907Na) in combination with an ionic-liquid electrolyte and a porous TiO2 layer. The inclusion of a SiO2 layer between the electrodes to prevent generation of unwanted back current and optimization of the thickness of the TiO2 layer are responsible for the enhanced performance.

  2. Smart photovoltaics based on dye-sensitized solar cells using photochromic spiropyran derivatives as photosensitizers

    SciTech Connect

    Ma, Shengbo; Ting, Hungkit; Ma, Yingzhuang; Zheng, Lingling; Zhang, Miwei; Xiao, Lixin E-mail: lxxiao@pku.edu.cn; Chen, Zhijian E-mail: lxxiao@pku.edu.cn

    2015-05-15

    In this paper, smart photovoltaic (SPV) devices, integrating both functions of solar cells and smart windows, was fabricated based on dye-sensitized solar cells using photochromic spiropyran derivatives SIBT as photosensitizers. SPV devices have self-regulated power conversion efficiency (PCE) and light transmission responding to the incident spectra due to the photoisomerization of SIBT. SIBT isomerize from closed-ring form to open-ring form under UV illumination, accompanied with enhanced visible light absorption and electron delocalization. Therefore, increased PCE and absorption in SPV devices were observed under UV treatment and the devices can be restored gradually to the initial status when kept in dark. The SPV devices have self-regulation of PCE and sunlight transmission responding to the changing sun spectra in different times of a day, providing a proper energy usage and a better sun-shading.

  3. High Efficiency Forster Resonance Energy Transfer in Solid-State Dye Sensitized Solar Cells

    SciTech Connect

    Mor, Gopal K.; Basham, James; Paulose, Maggie; Kim, Sanghoon; Varghese, Oomman K.; Vaish, Amit; Yoriya, Sorachon; Grimes, Craig A.

    2010-07-14

    Solid-state dye-sensitized solar cells (SS-DSCs) offer the potential to make low cost solar power a reality, however their photoconversion efficiency must first be increased. The dyes used are commonly narrow band with high absorption coefficients, while conventional photovoltaic operation requires proper band edge alignment significantly limiting the dyes and charge transporting materials that can be used in combination. We demonstrate a significant enhancement in the light harvesting and photocurrent generation of SS-DSCs due to Förster resonance energy transfer (FRET). TiO{sub 2} nanotube array films are sensitized with red/near IR absorbing SQ-1 acceptor dye, subsequently intercalated with Spiro-OMeTAD blended with a visible light absorbing DCM-pyran donor dye. The calculated Förster radius is 6.1 nm. The donor molecules contribute a FRET-based maximum IPCE of 25% with a corresponding excitation transfer efficiency of approximately 67.5%.

  4. Membrane-Inspired Acidically Stable Dye-Sensitized Photocathode for Solar Fuel Production.

    PubMed

    Click, Kevin A; Beauchamp, Damian R; Huang, Zhongjie; Chen, Weilin; Wu, Yiying

    2016-02-01

    Tandem dye-sensitized photoelectrochemical cells (DSPECs) for water splitting are a promising method for sustainable energy conversion but so far have been limited by their lack of aqueous stability and photocurrent mismatch between the cathode and anode. In nature, membrane-enabled subcellular compartmentation is a general approach to control local chemical environments in the cell. The hydrophobic tails of the lipid make the bilayer impermeable to ions and hydrophilic molecules. Herein we report the use of an organic donor-acceptor dye that prevents both dye desorption and semiconductor degradation by mimicking the hydrophobic/hydrophilic properties of lipid bilayer membranes. The dual-functional photosensitizer (denoted as BH4) allows for efficient light harvesting while also protecting the semiconductor surface from protons and water via its hydrophobic π linker. The protection afforded by this membrane-mimicking dye gives this system excellent stability in extremely acidic (pH 0) conditions. The acidic stability also allows for the use of cubane molybdenum-sulfide cluster as the hydrogen evolution reaction (HER) catalyst. This system produces a proton-reducing current of 183 ± 36 μA/cm(2) (0 V vs NHE with 300 W Xe lamp) for an unprecedented 16 h with no degradation. These results introduce a method for developing high-current, low-pH DSPECs and are a significant move toward practical dye-sensitized solar fuel production. PMID:26744766

  5. Ultrafast interfacial charge transfer dynamics in dye-sensitized and quantum dot solar cell

    NASA Astrophysics Data System (ADS)

    Ghosh, Hirendra N.

    2013-02-01

    Dye sensitized solar cell (DSSC) appeared to be one of the good discovery for the solution of energy problem. We have been involved in studying ultrafast interfacial electron transfer dynamics in DSSC using femtosecond laser spectroscopy. However it has been realized that it is very difficult to design and develop higher efficient one, due to thermodynamic limitation. Again in DSSC most of the absorbed photon energy is lost as heat within the cell, which apart from decreasing the efficiency also destabilizes the device. It has been realized that quantum dot solar cell (QDSC) are the best bet where the sensitizer dye molecules can be replaced by suitable quantum dot (QD) materials in solar cell. The quantum-confinement effect in semiconductors modifies their electronic structure, which is a very important aspect of these materials. For photovoltaic applications, a long-lived charge separation remains one of the most essential criteria. One of the problems in using QDs for photovoltaic applications is their fast charge recombination caused by nonradiative Auger processes, which occur predominantly at lower particle sizes due to an increase in the Coulomb interaction between electrons and holes. Various approaches, such as the use of metal-semiconductor composites, semiconductor-polymer composite, and semiconductor core-shell heterostructures, have been attempted to minimize the fast recombination between electrons and holes. To make higher efficient solar devices it has been realised that it is very important to understand charge carrier and electron transfer dynamics in QD and QD sensitized semiconductor nanostructured materials. In the present talk, we are going to discuss on recent works on ultrafast electron transfer dynamics in dye-sensitized TiO2 nanoparticles/film [1-12] and charge (electron/hole) transfer dynamics in quantum dot core-shell nano-structured materials [13-17].

  6. Interaction of Sensitizing Dyes with Nanostructured TiO2 Film in Dye-Sensitized Solar Cells Using Terahertz Spectroscopy.

    PubMed

    Ghann, William; Rahman, Aunik; Rahman, Anis; Uddin, Jamal

    2016-01-01

    The objective of this investigation was to shed light on the nature of interaction of different organic dyes and an inorganic dye, Ruthenium (II) polypyridine complex, with TiO2 nanoparticles. TiO2 is commonly deployed as an efficient energy transfer electrode in dye sensitized solar cells. The efficiency of dye sensitized solar cells is a function of the interaction of a dye with the electrode material such as TiO2. To the best of our knowledge the present study is the first effort in the determination of terahertz absorbance signals, investigation of real-time dye permeation kinetics, and the surface profiling and 3D imaging of dye sensitized TiO2 films. Herein, we report that the terahertz spectra of the natural dye sensitized TiO2 films were distinctively different from that of the inorganic dye with prominent absorption of natural dyes occurring at approximately the same wavelength. It was observed that the permeation of the natural dyes were more uniform through the layers of the mesoporous TiO2 compared to the inorganic dye. Finally, defects and flaws on TiO2 film were easily recognized via surface profiling and 3D imaging of the films. The findings thus offer a new approach in characterization of dye sensitized solar cells. PMID:27443236

  7. Interaction of Sensitizing Dyes with Nanostructured TiO2 Film in Dye-Sensitized Solar Cells Using Terahertz Spectroscopy

    PubMed Central

    Ghann, William; Rahman, Aunik; Rahman, Anis; Uddin, Jamal

    2016-01-01

    The objective of this investigation was to shed light on the nature of interaction of different organic dyes and an inorganic dye, Ruthenium (II) polypyridine complex, with TiO2 nanoparticles. TiO2 is commonly deployed as an efficient energy transfer electrode in dye sensitized solar cells. The efficiency of dye sensitized solar cells is a function of the interaction of a dye with the electrode material such as TiO2. To the best of our knowledge the present study is the first effort in the determination of terahertz absorbance signals, investigation of real-time dye permeation kinetics, and the surface profiling and 3D imaging of dye sensitized TiO2 films. Herein, we report that the terahertz spectra of the natural dye sensitized TiO2 films were distinctively different from that of the inorganic dye with prominent absorption of natural dyes occurring at approximately the same wavelength. It was observed that the permeation of the natural dyes were more uniform through the layers of the mesoporous TiO2 compared to the inorganic dye. Finally, defects and flaws on TiO2 film were easily recognized via surface profiling and 3D imaging of the films. The findings thus offer a new approach in characterization of dye sensitized solar cells. PMID:27443236

  8. Interaction of Sensitizing Dyes with Nanostructured TiO2 Film in Dye-Sensitized Solar Cells Using Terahertz Spectroscopy

    NASA Astrophysics Data System (ADS)

    Ghann, William; Rahman, Aunik; Rahman, Anis; Uddin, Jamal

    2016-07-01

    The objective of this investigation was to shed light on the nature of interaction of different organic dyes and an inorganic dye, Ruthenium (II) polypyridine complex, with TiO2 nanoparticles. TiO2 is commonly deployed as an efficient energy transfer electrode in dye sensitized solar cells. The efficiency of dye sensitized solar cells is a function of the interaction of a dye with the electrode material such as TiO2. To the best of our knowledge the present study is the first effort in the determination of terahertz absorbance signals, investigation of real-time dye permeation kinetics, and the surface profiling and 3D imaging of dye sensitized TiO2 films. Herein, we report that the terahertz spectra of the natural dye sensitized TiO2 films were distinctively different from that of the inorganic dye with prominent absorption of natural dyes occurring at approximately the same wavelength. It was observed that the permeation of the natural dyes were more uniform through the layers of the mesoporous TiO2 compared to the inorganic dye. Finally, defects and flaws on TiO2 film were easily recognized via surface profiling and 3D imaging of the films. The findings thus offer a new approach in characterization of dye sensitized solar cells.

  9. Influence of TiCl4 post-treatment condition on TiO2 electrode for enhancement photovoltaic efficiency of dye-sensitized solar cells.

    PubMed

    Eom, Tae Sung; Kim, Kyung Hwan; Bark, Chung Wung; Choi, Hyung Wook

    2014-10-01

    Titanium tetrachloride (TiCl4) treatment processed by chemical bath deposition is usually adopted as pre- and post-treatment for nanocrystalline titanium dioxide (TiO2) film deposition in the dye-sensitized solar cells (DSSCs) technology. TiCl4 post-treatment is a widely known method capable of improving the performance of dye-sensitized solar cells. In this work, the effect of TiCl4 post-treatment on the TiO2 electrode is proposed and compared to the untreated film. A TiO2 passivating layer was deposited on FTO glass by RF magnetron sputtering. The TiO2 sol prepared sol-gel method, nanoporous TiO2 upper layer was deposited by screen printing method on the passivating layer. TiCl4 post-treatment was deposited on the substrate by hydrolysis of TiCl4 aqueous solution. Crystalline structure was adjusted by various TiCl4 concentration and dipping time: 20 mM-150 mM and 30 min-120 min. The conversion efficiency was measured by solar simulator (100 mW/cm2). The dye-sensitized solar cell using TiCl4 post-treatment was measured the maximum conversion efficiency of 5.04% due to electron transport effectively. As a result, the DSSCs based on TiCl4 post-treatment showed better photovoltaic performance than cells made purely of TiO2 nanoparticles. The relative DSSCs devices are characterized in terms of short circuit current density, open circuit voltage, fill factor, conversion efficiency. PMID:25942852

  10. Demonstrating Electron Transfer and Nanotechnology: A Natural Dye-Sensitized Nanocrystalline Energy Converter

    NASA Astrophysics Data System (ADS)

    Smestad, Greg P.; Gratzel, Michael

    1998-06-01

    A unique solar cell fabrication procedure has been developed using natural anthocyanin dyes extracted from berries. It can be reproduced with a minimum amount of resources in order to provide an interdisciplinary approach for lower-division undergraduate students learning the basic principles of biological extraction, physical chemistry, and spectroscopy as well as environmental science and electron transfer. Electron transfer is the basis of the energetics that drives the processes of life on Earth, occurring in both the mitochondrial membranes of living cells and in the thylakoid membranes of photosynthetic cells of green plants and algae (1). Although we depend on the petroleum and agricultural products of this electron and energy transfer, one of the greatest challenges of the 21st century is that we have yet to create devices that can be used to tap directly into the ultimate source of this energy on an economic scale. An experimental lab procedure was therefore created in order to illustrate the connections between natural and man-made solar conversion within a three-hour lab period.

  11. Effect of photoanode thickness on electrochemical performance of dye sensitized solar cell

    SciTech Connect

    Khatani, Mehboob Hamid, Nor Hisham Sahmer, Ahmed Zahrin; Mohamed, Norani Muti Muhsan, Ali Samer

    2015-07-22

    The thickness of photoanode is crucial as it adsorbed a large amount of dye molecules that provide electrons for generation of electricity in dye sensitized solar cell (DSC). Thus, in order to realize the practical application of DSC, study on various thickness of photoanode need to be carried out to analyze its effect on the electrochemical behavior of dye sensitized solar cell. To enhance the conversion efficiency, an additional layer of TiO{sub 2} using TiCl{sub 4} treatment was deposited prior to the deposition of the photoanode (active area of 1cm{sup 2}) with the thickness of 6, 12, 18, 24, and 30 µm on fluorine doped tin oxide (FTO) glass substrate. The resulting photoanode after the soak in N719 dye for more than 12hrs were used to be assembled in a test cell in combination with liquid electrolyte and counter electrode. The fabricated cells were characterized by solar simulator, ultraviolet-visible spectroscopy (UV-VIS), and electrochemical impedance spectroscopy (EIS). Scanning electron microscopy (SEM) was used to approximate the thickness of photoanode. An optimum power conversion efficiency of 4.54% was obtained for the cell fabricated with 18 µm photoanode thickness. This is attributed to the reduced resistance related to electron transport in the TiO{sub 2}/dye/electrolyte interface as proven by the EIS result. This led to the reduction of internal resistance, the increase in the electron life time and the improvement in the conversion efficiency.

  12. Fabrication of dye-sensitized solar cell (DSSC) using annato seeds (Bixa orellana Linn)

    SciTech Connect

    Haryanto, Ditia Allindira; Landuma, Suarni; Purwanto, Agus

    2014-02-24

    The Fabrication of dye sensitized solar cell (DSSC) using Annato seeds has been conducted in this study. Annato seeds (Bixa orellana Linn) used as a sensitizer for dye sensitized solar cell. The experimental parameter was concentration of natural dye. Annato seeds was extracted using etanol solution and the concentration was controlled by varying mass of Annato seeds. A semiconductor TiO{sub 2} was prepared by a screen printing method for coating glass use paste of TiO{sub 2}. Construction DSSC used layered systems (sandwich) consists of working electrode (TiO{sub 2} semiconductor-dye) and counter electrode (platina). Both are placed on conductive glass and electrolytes that occur electrons cycle. The characterization of thin layer of TiO{sub 2} was conducted using SEM (Scanning Electron Microscpy) analysis showed the surface morphology of TiO{sub 2} thin layer and the cross section of a thin layer of TiO{sub 2} with a thickness of 15–19 μm. Characterization of natural dye extract was determined using UV-Vis spectrometry analysis shows the wavelength range annato seeds is 328–515 nm, and the voltage (V{sub oc}) and electric current (I{sub sc}) resulted in keithley test for 30 gram, 40 gram, and 50 gram were 0,4000 V; 0,4251 V; 0,4502 V and 0,000074 A; 0,000458 A; 0,000857 A, respectively. The efficiencies of the fabricated solar cells using annato seeds as senstizer for each varying mass are 0,00799%, 0,01237%, and 0,05696%.

  13. Triazoloisoquinoline-based dual functional dyestuff for dye-sensitized solar cells

    SciTech Connect

    Lee, Che-Lung; Lee, Wen-Hsi; Yang, Cheng-Hsien; Yang, Hao-Hsun; Chang, Jia-Yaw

    2013-01-15

    Graphical abstract: They consist of treating triazoloisoquinolines substituted tetramethyl-dioxaborolane (2) with 5-formyl-2-bromothiophene under conditions for Suzuki coupling to produce 5-(4-(3-oxo-[1,2,4]triazolo[3,4-a]isoquinolin-2(3H)-yl)phenyl) thiophene-2-carbaldehyde (3). Knoevenagel condensation of compound 3 with cyanoacrylic acid is carried out in the presence of piperidine, and after precipitation and purification with silica gel chromatography, the final dyestuff 4L is obtained as a yellow powder. This product has been characterized by spectroscopic analyses. Display Omitted Highlights: ► This new dyestuff investigated the role of triazoloisoquinoline dyestuffs as co-adsorbents and co-sensitizers with N719. ► The results show that co-adsorption of N719 sensitizer with dyestuff 5 increases the photocurrent in 1–0.25 molar ratio. ► This improved conversion efficiency is attributed to the insulating molecular layer, and the light harvesting effect at shorter-wavelength regions. -- Abstract: Triazoloisoquinoline contains electron-rich nitrogen and oxygen heteroatoms in a heterocyclic structure with high electron-donating ability. By utilizing this feature, two organic dyesutffs containing triazoloisoquinoline were synthesized and used in the fabrication of dye-sensitized solar cells (DSSCs), overcoming the deficiency of ruthenium dyestuff absorption in the blue part of the visible spectrum. This method also fills the blanks of ruthenium dyestuff sensitized TiO{sub 2} film, and forms a compact insulating molecular layer due to the nature of small molecular organic dyestuffs. The incident photon-to-electron conversion efficiency of N719 at shorter wavelength regions is 35%. After addition of triazoloisoquinoline-based dyestuff for co-sensitization, the IPCE at 350–500 nm increased significantly. This can be attributed to the increased photocurrent of the cells, which improves the dye-sensitized photoelectric conversion efficiency from 4.49% to 5

  14. A flexible polypyrrole-coated fabric counter electrode for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Xu, Jie; Li, Meixia; Wu, Lei; Sun, Yongyuan; Zhu, Ligen; Gu, Shaojin; Liu, Li; Bai, Zikui; Fang, Dong; Xu, Weilin

    2014-07-01

    The current dye-sensitized solar cell (DSSC) technology is mostly based on fluorine doped tin oxide (FTO) coated glass substrate. The main problem with the FTO glass substrate is its rigidity, heavyweight and high cost. DSSCs with a fabric as substrate not only offer the advantages of flexibility, stretchability and light mass, but also provide the opportunities for easy implantation to wearable electronics. Herein, a novel fabric counter electrode (CE) for DSSCs has been reported employing a daily-used cotton fabric as substrate and polypyrrole (PPy) as catalytic material. Nickel (Ni) is deposited on the cotton fabric as metal contact by a simple electroless plating method to replace the expensive FTO. PPy is synthesized by in situ polymerization of pyrrole monomer on the Ni-coated fabric. The fabric CE shows sufficient catalytic activity towards the reduction of I3-. The DSSC fabricated using the fabric CE exhibits power conversion efficiency of ∼3.30% under AM 1.5.

  15. Fabrication of carbon-coated silicon nanowires and their application in dye-sensitized solar cells.

    PubMed

    Kim, Junhee; Lim, Jeongmin; Kim, Minsoo; Lee, Hae-Seok; Jun, Yongseok; Kim, Donghwan

    2014-11-12

    We report the fabrication of silicon/carbon core/shell nanowire arrays using a two-step process, involving electroless metal deposition and chemical vapor deposition. In general, foreign shell materials that sheath core materials change the inherent characteristics of the core materials. The carbon coating functionalized the silicon nanowire arrays, which subsequently showed electrocatalytic activities for the reduction of iodide/triiodide. This was verified by cyclic voltammetry and electrochemical impedance spectroscopy. We employed the carbon-coated silicon nanowire arrays in dye-sensitized solar cells as counter electrodes. We optimized the carbon shells to maximize the photovoltaic performance of the resulting devices, and subsequently, a peak power conversion efficiency of 9.22% was achieved. PMID:25319204

  16. Materials, Interfaces, and Photon Confiement in Dye-Sensitized Solar Cells

    SciTech Connect

    Lee, B.; Hwang, D.; Guo, P. J.; Ho, S. T.; Buchholtz, D. B.; Wang, C. Y.; Chang, R.P.H.

    2010-11-18

    A series of experiments have been carried out to study the effects of materials quality, surface and interfacial modification, and photon confinement on standard dye-sensitized solar cells. For these studies, both physical and optical characterization of the materials has been performed in detail. In addition, DC and AC impedance measurements along with kinetic charge-transport modeling of experimental results have yielded information on how to systematically optimize the cell efficiency. The same kinetic model has been used to interpret the results of a series of experiments on interfacial modification studies using fluorine etching in combination with TiCl{sub 4} surface treatment. By using specially designed photonic crystals to confine the photons in the cells, it is shown that the best cell efficiency can be further increased by about 13%.

  17. Magnetic field effects in dye-sensitized solar cells controlled by different cell architecture.

    PubMed

    Klein, M; Pankiewicz, R; Zalas, M; Stampor, W

    2016-01-01

    The charge recombination and exciton dissociation are generally recognized as the basic electronic processes limiting the efficiency of photovoltaic devices. In this work, we propose a detailed mechanism of photocurrent generation in dye-sensitized solar cells (DSSCs) examined by magnetic field effect (MFE) technique. Here we demonstrate that the magnitude of the MFE on photocurrent in DSSCs can be controlled by the radius and spin coherence time of electron-hole (e-h) pairs which are experimentally modified by the photoanode morphology (TiO2 nanoparticles or nanotubes) and the electronic orbital structure of various dye molecules (ruthenium N719, dinuclear ruthenium B1 and fully organic squaraine SQ2 dyes). The observed MFE is attributed to magnetic-field-induced spin-mixing of (e-h) pairs according to the Δg mechanism. PMID:27440452

  18. Spray deposition of electrospun TiO2 nanorods for dye-sensitized solar cell

    NASA Astrophysics Data System (ADS)

    Fujihara, K.; Kumar, A.; Jose, R.; Ramakrishna, S.; Uchida, S.

    2007-09-01

    A simple technique was developed to fabricate a large-area TiO2 electrode layer using electrospun nanorods for dye-sensitized solar cells (DSSCs). Using this technique, we assembled DSSCs of area ~1 cm2 consisting of a thin TiO2 nanoparticle layer and a thick TiO2 nanorod layer as electrode. The TiO2 nanorods were obtained by mechanically grinding electrospun TiO2 nanofibers. A titania sol was first spin-coated on a conductive glass plate and a TiO2 nanorod layer was next spray dried on it to fabricate TiO2 nanoparticle/nanorod layers. These layers were subsequently sintered. The best-performing DSSC evaluated under AM1.5G (1 sun) condition gave current density ~13.6 mA cm-2, open circuit voltage ~0.8 V, fill factor ~51% and energy conversion efficiency ~5.8%.

  19. Effect of polymer electrolyte on the performance of natural dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Adel, R.; Abdallah, T.; Moustafa, Y. M.; Al-sabagh, A. M.; Talaat, H.

    2015-10-01

    Polymer electrolyte based on polyacrylonitrile (PAN), Ethylene Carbonate (EC) and Acetonitrile (ACN) mixed with Potassium Iodide and Iodine in liquid and thin film forms were employed in natural dye sensitized solar cells (NDSSCs). Three natural dyes; black berry, hibiscus and rose are used as the sensitizing dye. The NDSSCs used, follow the configuration: FTO/TiO2/Natural Dye/Electrolyte/ Carbon/FTO. The liquid form polymer electrolyte with black berry natural dye gives an increase of 111% in short circuit photocurrent density (Jsc), 17.5% to open circuit voltage (Voc), fill factor of 0.57 ± 0.05 and three times increase in the conversion efficiency of 0.242 ± 0.012% compared to the iodine electrolyte.

  20. Robust polyaniline-graphene complex counter electrodes for efficient dye-sensitized solar cells.

    PubMed

    He, Benlin; Tang, Qunwei; Wang, Min; Chen, Haiyan; Yuan, Shuangshuang

    2014-06-11

    With an aim of accelerating the charge transfer between polyaniline (PANi) and graphene, polyaniline-graphene (PANi-graphene) complexes are synthesized by a reflux technique and employed as counter electrodes (CEs) for dye-sensitized solar cells (DSSCs). Because of the easy charge-transfer between PANi (N atoms) and graphene (C atoms) by a covalent bond, electrical conduction and electrocatalysis of PANi-graphene complex CEs, and therefore power conversion efficiency of their DSSCs have been elevated in comparison with that of PANi-only CE. The resultant PANi-graphene complex CEs are characterized by spectral analysis, morphology observation, and electrochemical tests. The DSSC employing PANi-8 wt ‰ graphene complex CE gives an impressive power conversion efficiency of 7.78%, which is higher than 6.24% from PANi-only and 6.52% from Pt-only CE-based DSSCs. PMID:24826943

  1. Tandem Dye-Sensitized Solar Cells Based on TCO-less Back Contact Bottom Electrodes

    NASA Astrophysics Data System (ADS)

    Baranwal, Ajay K.; Fujikawa, Naotaka; Nishimura, Terumi; Ogomi, Yuhei; Pandey, Shyam S.; Ma, Tingli; Hayase, Shuzi

    2016-04-01

    Mechanically stacked and series connected tandem dye sensitized solar cells (T-DSSCs) are fabricated in novel architectures. The architecture consist of TCO tandem DSSCs stacked with TCO-less back contact DSSCs as bottom electrodes (TCO-less tandem DSSCs). Resulting TCO-less tandem DSSCs architecture finds its usefulness in efficient photon harvesting due to improved light transmission and enhanced photons reaching to the bottom electrodes. The fabricated tandem performance was verified with visible light harvesting model dyes D131 and N719 as a proof of concept and provided the photoconversion efficiency (PCE) of 6.06% under simulated condition. Introduction of panchromatic photon harvesting by utilizing near infrared light absorbing Si-phthalocyanine dye in combination with the modified tandem DSSC architecture led to enhancement in the PCE up to 7.19%.

  2. Counter electrodes from binary ruthenium selenide alloys for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Li, Pinjiang; Cai, Hongyuan; Tang, Qunwei; He, Benlin; Lin, Lin

    2014-12-01

    Dye-sensitized solar cell (DSSC) is a promising solution to global energy and environmental problems because of its merits on clean, cost-effectiveness, relatively high efficiency, and easy fabrication. However, the reduction of fabrication cost without sacrifice of power conversion efficiencies of the DSSCs is a golden rule for their commercialization. Here we design a new binary ruthenium selenide (Ru-Se) alloy counter electrodes (CEs) by a low-temperature hydrothermal reduction method. The electrochemical behaviors are evaluated by cyclic voltammogram, electrochemical impedance, and Tafel measurements, giving an optimized Ru/Se molar ratio of 1:1. The DSSC device with RuSe alloy CE achieves a power conversion efficiency of 7.15%, which is higher than 5.79% from Pt-only CE based DSSC. The new concept, easy process along with promising results provide a new approach for reducing cost but enhancing photovoltaic performances of DSSCs.

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

    SciTech Connect

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

    2010-05-15

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

  4. Dissolution Engineering of Platinum Alloy Counter Electrodes in Dye-Sensitized Solar Cells.

    PubMed

    Tang, Qunwei; Zhang, Huihui; Meng, Yuanyuan; He, Benlin; Yu, Liangmin

    2015-09-21

    The dissolution of platinum (Pt) has been one of the heart issues in developing advanced dye-sensitized solar cells (DSSCs). We present here the experimental realization of stable counter-electrode (CE) electrocatalysts by alloying Pt with transition metals for enhanced dissolution resistance to state-of-the-art iodide/triiodide (I(-)/I3(-)) redox electrolyte. Our focus is placed on the systematic studies of dissolution engineering for PtM0.05 (M=Ni, Co, Fe, Pd, Mo, Cu, Cr, and Au) alloy CE electrocatalysts along with mechanism analysis from thermodynamical aspects, yielding more negative Gibbs free energies for the dissolution reactions of transition metals. The competitive reactions between transition metals with iodide species (I3(-), I2) could protect the Pt atoms from being dissolved by redox electrolyte and therefore remain the high catalytic activity of the Pt electrode. PMID:26220170

  5. Nanoforest Nb2O5 Photoanodes for Dye-Sensitized Solar Cells by Pulsed Laser Deposition

    SciTech Connect

    Ghosh, Rudresh; Brennaman, Kyle M.; Uher, Tim; Ok, Myoung-Ryul; Samulski, Edward T.; McNeil, L. E.; Meyer, Thomas J.; Lopez, Rene

    2011-10-26

    Vertically aligned bundles of Nb₂O₅ nanocrystals were fabricated by pulsed laser deposition (PLD) and tested as a photoanode material in dye-sensitized solar cells (DSSC). They were characterized using scanning and transmission electron microscopies, optical absorption spectroscopy (UV–vis), and incident-photon-to-current efficiency (IPCE) experiments. The background gas composition and the thickness of the films were varied to determine the influence of those parameters in the photoanode behavior. An optimal background pressure of oxygen during deposition was found to produce a photoanode structure that both achieves high dye loading and enhanced photoelectrochemical performance. For optimal structures, IPCE values up to 40% and APCE values around 90% were obtained with the N₃ dye and I₃{sup –}/I{sup –} couple in acetonitrile with open circuit voltage of 0.71 V and 2.41% power conversion efficiency.

  6. Highly transparent metal selenide counter electrodes for bifacial dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Li, Pinjiang; Tang, Qunwei

    2016-06-01

    Creation of transparent counter electrode (CE) electrocatalysts for bifacial dye-sensitized solar cells (DSSCs) is a persistent objective for reducing cost of photovoltaic conversion. We present here the experimental realization of highly transparent CuSe CEs by a mild solution method for liquid-junction bifacial DSSCs. The resultant CuSe CEs show superior electrocatalytic activity toward I3- reduction reaction. By optimizing the pH values in synthesizing CuSe electrodes, the maximal front efficiency of 6.21% and rear efficiency of 4.72% are recorded on the corresponding bifacial DSSC. Both catalytic activity and photovoltaic performances can be further elevated by alloying CuSe with Co or Fe, yielding promising efficiencies of 7.81% and 5.38% under front and rear irradiations, respectively.

  7. Dye-sensitized solar cell counter electrodes based on carbon nanotubes.

    PubMed

    Hwang, Seunghwa; Batmunkh, Munkhbayar; Nine, Md J; Chung, Hanshik; Jeong, Hyomin

    2015-01-12

    Dye-sensitized solar cells (DSSCs) have received significant attention from the scientific community since their discovery in 1991. However, the high cost and scarcity of platinum has motivated researchers to seek other suitable materials for the counter electrode of DSSCs. Owing to their exceptional properties such as high conductivity, good electrochemical activity, and low cost, carbon nanotubes (CNTs) have been considered as promising alternatives to expensive platinum (Pt) in the counter electrode of DSSCs. Herein, we provide a Minireview of the CNTs use in the counter electrode of DSSCs. A brief overview of Pt-based counter electrodes is also discussed. Particular attention is given to the recent advances of counter electrodes with CNT-based composite structures. PMID:25367083

  8. Recovering degraded quasi-solid-state dye-sensitized solar cells by applying electrical pulses

    PubMed Central

    Zhang, Xi; Huang, Xuezhen

    2013-01-01

    We discovered a method of applying forward pulsed bias to recover the degradation of quasi-solid-state dye-sensitized solar cells (DSSCs). Up to 30.7% of the power conversion efficiency (η) of a degraded poly (vinylidene fluoride) (PVDF) based DSSC was recovered by a double-pulse. The recovered η remained higher than that before the double-pulse treatment for at least 28 days. It is deduced that the blocking of ion-transport channels in the quasi-solid-state electrolyte causes degradation of the DSSCs. This study will shed light on the efficiency enhancement and long-term stability of quasi-solid-state DSSCs. PMID:23545782

  9. Implication of Blocking Layer Functioning with the Effect of Temperature in Dye-Sensitized Solar Cells.

    PubMed

    Kou, Dongxing; Chen, Shuanghong; Hu, Linhua; Wu, Sixin; Dai, Songyuan

    2016-06-01

    The properties of thin titanium dioxide blocking layers onto TCO in dye-sensitized solar cells (DSCs) have been widely reported as their intensity dependence of illumination intensity. Herein, a further investigation about their functioning with the effect of temperature is developed. The electron recombination process, photovoltage response on illumination intensity and photocurrent-voltage properties for DSCs with/without blocking layer at different temperatures are detected. It is found that the electron recombination via TCO becomes increasingly pronounced with increasing temperature and the effect of blocking layer is extremely temperature dependent. The band bending of the compact layer is more effectively to block electron losses at high temperatures, preventing large falloff of photovoltage. Hence, a resistive layer at the surface of TCO keeps comparable cell performances without falloff over a wide temperature range, while the device without blocking layer shows large decrease by over 10% at high temperature for contrast. PMID:27427620

  10. Blue-coloured highly efficient dye-sensitized solar cells by implementing the diketopyrrolopyrrole chromophore.

    PubMed

    Yum, Jun-Ho; Holcombe, Thomas W; Kim, Yongjoo; Rakstys, Kasparas; Moehl, Thomas; Teuscher, Joel; Delcamp, Jared H; Nazeeruddin, Mohammed K; Grätzel, Michael

    2013-01-01

    The paradigm shift in dye sensitized solar cells (DSCs) - towards donor- π bridge-acceptor (D-π-A) dyes - increases the performances of DSCs and challenges established design principles. Framed by this shifting landscape, a series of four diketopyrrolopyrrole (DPP)-based sensitizers utilizing the donor-chromophore-anchor (D-C-A) motif were investigated computationally, spectroscopically, and fabricated by systematic evaluation of finished photovoltaic cells. In all cases, the [Co(bpy)3](3+/2+) redox-shuttle afforded superior performance compared to I3(-)/I(-). Aesthetically, careful molecular engineering of the DPP chromophore yielded the first example of a high-performance blue DSC - a challenge unmet since the inception of this photovoltaic technology: DPP17 yields over 10% power conversion efficiency (PCE) with the [Co(bpy)3](3+/2+) electrolyte at full AM 1.5 G simulated sun light. PMID:23945746

  11. Recent advances in alternative counter electrode materials for Co-mediated dye-sensitized solar cells.

    PubMed

    Yun, Sining; Liu, Yanfang; Zhang, Taihong; Ahmad, Shahzada

    2015-07-28

    Recently, considerable attention has been paid to dye-sensitized solar cells (DSSCs) which are based on Co(2+)/Co(3+) redox shuttles, because of their unparalleled merits including higher redox potential, reduced corrosiveness towards metallic conductors, low costs and high power conversion efficiencies (PCE) (13%). The counter electrode (CE) is an essential component in DSSCs, and plays a crucial role in catalyzing Co(3+) ion reduction in Co-based DSSCs. In this mini-review, we review recent developments in CE materials for Co-mediated DSSCs including: noble metal platinum (Pt), carbon materials, transition metal compounds (TMCs), polymers, and their corresponding hybrids, highlighting important contributions worldwide that promise low cost, efficient, and robust Co-mediated DSSC systems. Additionally, the crucial challenges associated with employing these low-cost CE catalysts for Co-based redox couples in DSSCs are stressed. PMID:26132719

  12. Cost-effective platinum alloy counter electrodes for liquid-junction dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Li, Yanjuan; Tang, Qunwei; Yu, Liangmin; Yan, Xuefeng; Dong, Lei

    2016-02-01

    One of the challenges in developing advanced dye-sensitized solar cells (DSSCs) is the pursuit of cost-effective and robust counter electrodes (CEs). We present here the successful synthesis of binary PtxM100-x (M = Ni, Co, Fe) alloy nanostructures on Ti foil by a facile and environmental-friendly strategy for utilization as CEs in liquid-junction DSSCs. Due to the reasonable charge-transfer ability and excellent electrocatalytic activity, the resultant DSSC yields a promising power conversion efficiency (PCE) of 6.42% with binary Pt0.28Ni99.72 CE in comparison with 6.18% for pristine Pt CE based device. The easy synthesis, cost-effectiveness, and good electrocatalytic property may help the Pt0.28Ni99.72 nanostructure stand out as an alternative CE electrocatalyst in a DSSC.

  13. Growth of Comb-like ZnO Nanostructures for Dye-sensitized Solar Cells Applications

    PubMed Central

    2009-01-01

    Dye-sensitized solar cells (DSSCs) were fabricated by using well-crystallized ZnO nanocombs directly grown onto the fluorine-doped tin oxide (FTO) via noncatalytic thermal evaporation process. The thin films of as-grown ZnO nanocombs were used as photoanode materials to fabricate the DSSCs, which exhibited an overall light to electricity conversion efficiency of 0.68% with a fill factor of 34%, short-circuit current of 3.14 mA/cm2, and open-circuit voltage of 0.671 V. To the best of our knowledge, this is first report in which thin film of ZnO nanocombs was used as photoanode materials to fabricate the DSSCs. PMID:20596445

  14. Application of Eu2O3/ZnO nanoparticles in dye sensitized solar cell

    NASA Astrophysics Data System (ADS)

    Kaur, Manveen; Verma, N. K.

    2013-06-01

    The synthesis of ZnO, Eu2O3 coated ZnO nanoparticles and their application in dye sensitized solar cells (DSSCs) has been reported. The synthesized samples have been characterized by XRD and the diffraction of crystal plane (222) of Eu2O3 was detected, demonstrating the existence of Eu2O3 on the surface of ZnO3, which has also been verified through EDAX. Compared to ZnO electrodes, Eu2O3 coated ZnO electrodes adsorbed more dye. Eu2O3 coating on ZnO forms an energy barrier, which suppresses the charge recombination. Consequently, the photoelectrochemical properties of the modified electrodes improved and the overall energy conversion efficiency η increased from 0.21% to 0.61% under the illumination of simulated light of 100mW/cm2.

  15. Comparative Analysis of Various Photoelectrodes for Dye-Sensitized Solar Cells.

    PubMed

    Ko, Kwan-Woo; Park, Jae-Hyoung; Song, Hye-Jin; Hong, Sungjun; Jun, Yongseok; Yoon, Soon-Gil; Hong, Young-Sik; Han, Chi-Hwan

    2015-11-01

    We prepared nanopastes containing various additives such as acetylene black (AB paste), 3,5-dinitrosalicylic acid (NSA paste) and SiC2 particles (SO paste), and these nanopastes were employed in preparation of photoelectrodes for dye sensitized solar cells (DSSCs). Photoelectrodes of AB, NSA and SO paste have characteristics of large pore size, superior interconnection among particles, and scattering due to spherical particle shape, respectively. Photovoltaic parameters of cells formed from the pastes were compared with cell formed from the paste without additive. Among the pastes, AB paste exhibited the best cell efficiency improvement of 9.647%. NSA paste also exhibited considerable cell efficiency improvement without much deleterious impact on transparency. The advantages and disadvantages of each nanopastes were analysed for the commercialization of DSSCs. PMID:26726673

  16. Dye-Sensitized Solar Cells Combining ZnO Nanotip Arrays and Nonliquid Gel Electrolytes

    NASA Astrophysics Data System (ADS)

    Chen, Hanhong; Duan, Ziqing; Lu, Yicheng; Du Pasquier, Aurelien

    2009-08-01

    We present a dye-sensitized solar cell (DSSC) using a nanostructured ZnO photoelectrode and a gel electrolyte. The photoelectrode consists of well-aligned ZnO nanotips on a Ga-doped ZnO (GZO) transparent conducting film. The GZO film (400 nm, sheet resistance ~25 Ω/sq, transmittance over 85% in the visible wavelength) and ZnO nanotips (3.2 μm length) are sequentially grown on a glass substrate using metalorganic chemical vapor deposition. The ZnO photoelectrode is sensitized with dye N719 and impregnated with N-methyl pyrolidinone (NMP) gelled with poly(vinyl-difluoroethylene-hexafluoropropylene) copolymer (PVDF-HFP). The cell exhibits an open-circuit voltage of 726 mV and a power conversion efficiency of 0.89% under one sun illumination. The aging testing shows that the cell using a gel electrolyte has better stability than its liquid electrolyte counterpart.

  17. Dye-sensitized solar cell employing zinc oxide aggregates grown in the presence of lithium

    DOEpatents

    Zhang, Qifeng; Cao, Guozhong

    2013-10-15

    Provided are a novel ZnO dye-sensitized solar cell and method of fabricating the same. In one embodiment, deliberately added lithium ions are used to mediate the growth of ZnO aggregates. The use of lithium provides ZnO aggregates that have advantageous microstructure, morphology, crystallinity, and operational characteristics. Employing lithium during aggregate synthesis results in a polydisperse collection of ZnO aggregates favorable for porosity and light scattering. The resulting nanocrystallites forming the aggregates have improved crystallinity and more favorable facets for dye molecule absorption. The lithium synthesis improves the surface stability of ZnO in acidic dyes. The procedures developed and disclosed herein also help ensure the formation of an aggregate film that has a high homogeneity of thickness, a high packing density, a high specific surface area, and good electrical contact between the film and the fluorine-doped tin oxide electrode and among the aggregate particles.

  18. The effect of ionic liquid electrolyte concentrations in dye sensitized solar cell using gel electrolyte

    NASA Astrophysics Data System (ADS)

    Pujiarti, H.; Arsyad, W. S.; Wulandari, P.; Hidayat, R.

    2014-09-01

    Dye Sensitized Solar Cells (DSSCs) have received much attention because of some advantages, such as using environment-friendly materials and requiring less high-tech equipment. Commonly DSSCs are built using conventional electrolyte solution, which is prone to electrolyte leakage and low stability. In this paper, we present the characteristics of DSSCs using gel electrolyte, which was made of ionic liquid and hybrid polymer gel, and the effect of ionic liquid concentration on their characteristics. The hybrid composite polymer was composed of siloxane and ethylene glycol polymer networks. Their working performances were investigated by the current-voltage (J-V) characterizations and small ac impedance measurements, which are correlated with the concentrations of ionic liquid electrolyte. The experimental results showed that cell working performance slightly decreased but the solution leakage problem was eliminated.

  19. Laser annealed composite titanium dioxide electrodes for dye-sensitized solar cells on glass and plastics

    NASA Astrophysics Data System (ADS)

    Pan, Heng; Ko, Seung Hwan; Misra, Nipun; Grigoropoulos, Costas P.

    2009-02-01

    We report a rapid and low temperature process for fabricating composite TiO2 electrodes for dye-sensitized solar cells on glass and plastics by in tandem spray deposition and laser annealing. A homogenized KrF excimer laser beam (248 nm) was used to layer-by-layer anneal spray deposited TiO2 nanoparticles. The produced TiO2 film is crack free and contains small particles (30 nm) mixed with different fractions of larger particles (100-200 nm) controlled by the applied laser fluence. Laser annealed double-layered structure is demonstrated for both doctor-blade deposited and spray-deposited electrodes and performance enhancement can be observed. The highest demonstrated all-laser-annealed cells utilizing ruthenium dye and liquid electrolyte showed power conversion efficiency of ˜3.8% under simulated illumination of 100 mW/cm2.

  20. Multistep electrochemical deposition of hierarchical platinum alloy counter electrodes for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Zhang, Junjun; Ma, Mingming; Tang, Qunwei; Yu, Liangmin

    2016-01-01

    The preferred platinum counter electrode (CE) has been a burden for commercialization of dye-sensitized solar cell (DSSC) due to high expense and chemical corrosion by liquid electrolyte. In the current study, we have successfully realized the multistep deposition of platinum alloy CEs including PtNi, PtFe, and PtCo for liquid-junction DSSC applications. The preliminary results demonstrate that the enhanced electrochemical activities are attributable to high charge-transfer ability and matching work functions of the PtM (M = Ni, Fe, Co) alloy CEs to redox potential of I-/I3- electrolyte. The resultant DSSCs yield impressive power conversion efficiencies of 8.65%, 7.48%, and 7.08% with PtNi, PtFe, and PtCo CEs, respectively. On behalf of the competitive reactions between transition metals with liquid electrolyte, the PtM alloy CEs display enhanced long-term stability.

  1. Can aliphatic anchoring groups be utilised with dyes for p-type dye sensitized solar cells?

    PubMed

    Hao, Yan; Wood, Christopher J; Clark, Charlotte A; Calladine, James A; Horvath, Raphael; Hanson-Heine, Magnus W D; Sun, Xue-Zhong; Clark, Ian P; Towrie, Michael; George, Michael W; Yang, Xichuan; Sun, Licheng; Gibson, Elizabeth A

    2016-05-01

    A series of novel laterally anchoring tetrahydroquinoline derivatives have been synthesized and investigated for their use in NiO-based p-type dye-sensitized solar cells. The kinetics of charge injection and recombination at the NiO-dye interface for these dyes have been thoroughly investigated using picosecond transient absorption and time-resolved infrared measurements. It was revealed that despite the anchoring unit being electronically decoupled from the dye structure, charge injection occurred on a sub picosecond timescale. However, rapid recombination was also observed due to the close proximity of the electron acceptor on the dyes to the NiO surface, ultimately limiting the performance of the p-DSCs. PMID:27055102

  2. Synthesis and Characterization of Zinc Oxide Nanosheets for Dye-Sensitized Solar Cells.

    PubMed

    Al-Heniti, S; Umar, Ahmad; Zaki, H M

    2015-12-01

    Zinc oxide (ZnO) nanosheets were synthesized by a simple and facile hydrothermal process and characterized in terms of their morphological, structural, compositional, optical and photovoltaic properties. The detailed characterization revealed that the synthesized ZnO material possess nanosheet morphologies which are grown in very high density, possessing well-crystallinity with wurtzite hexagonal phase and exhibiting good optical properties. Further, the synthesized ZnO nanosheets were used as photoanode material to fabricate efficient dye-sensitized solar cell (DSSC). The fabricated DSSC shows an overall light-to-electricity conversion efficiency of -1.57%, open-circuit voltage (V(OC)) of 0.552 V, short-circuit currents (J(SC)) of -7.2 mA/cm2 and fill factors (FF) of 0.40. PMID:26682439

  3. Magnetic field effects in dye-sensitized solar cells controlled by different cell architecture

    PubMed Central

    Klein, M.; Pankiewicz, R.; Zalas, M.; Stampor, W.

    2016-01-01

    The charge recombination and exciton dissociation are generally recognized as the basic electronic processes limiting the efficiency of photovoltaic devices. In this work, we propose a detailed mechanism of photocurrent generation in dye-sensitized solar cells (DSSCs) examined by magnetic field effect (MFE) technique. Here we demonstrate that the magnitude of the MFE on photocurrent in DSSCs can be controlled by the radius and spin coherence time of electron-hole (e-h) pairs which are experimentally modified by the photoanode morphology (TiO2 nanoparticles or nanotubes) and the electronic orbital structure of various dye molecules (ruthenium N719, dinuclear ruthenium B1 and fully organic squaraine SQ2 dyes). The observed MFE is attributed to magnetic-field-induced spin-mixing of (e-h) pairs according to the Δg mechanism. PMID:27440452

  4. Dyes extracted from Trigonella seeds as photosensitizers for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Batniji, Amal; Abdel-Latif, Monzir S.; El-Agez, Taher M.; Taya, Sofyan A.; Ghamri, Hatem

    2016-06-01

    In this paper, the extract of Trigonella seeds was used as sensitizer for dye-sensitized solar cells (DSSCs). The natural dye was extracted from the seeds using water and alcohol as solvents for the raw material. The UV-Vis absorption spectra of Trigonella extract solution and dye adsorbed on TiO2 film were measured. DSSCs sensitized by Trigonella extracted using water as a solvent exhibited better performance with efficiency of 0.215 %. The performance of the fabricated DSSCs was attempted to enhance by acid treatment of the FTO substrates with HNO3, H3PO4, and H2SO4. Electrochemical impedance spectroscopy of the fabricated cells was also carried out.

  5. Effective solid electrolyte based on benzothiazolium for dye-sensitized solar cells.

    PubMed

    Han, Lu; Wang, Ye Feng; Zeng, Jing Hui

    2014-12-24

    Thiaozole/benzothiaozole-based dicationic conductors were synthesized and applied as solid-state electrolyte in dye-sensitized solar cells (DSSCs). X-ray diffraction, scanning electron microscopy, thermal gravimetric analysis, steady-state voltammogram, photocurrent intensity-photovoltage test, and electrochemical impedance spectroscopy are used to characterize the materials and the mechanism of the cell performance. Compared to the traditional monocationic crystals, the dicationic crystals have a larger size and can provide more opportunities to fine-tune their physical/chemical properties. As a consequence, this solid-state electrolyte-based DSSC achieved photoelectric conversion efficiency of 7.90% under full air-mass (AM 1.5) sunlight (100 mW·cm(-2)). PMID:25469936

  6. Graphene-based large area dye-sensitized solar cell modules

    NASA Astrophysics Data System (ADS)

    Casaluci, Simone; Gemmi, Mauro; Pellegrini, Vittorio; di Carlo, Aldo; Bonaccorso, Francesco

    2016-02-01

    We demonstrate spray coating of graphene ink as a viable method for large-area fabrication of graphene-based dye-sensitized solar cell (DSSC) modules. A graphene-based ink produced by liquid phase exfoliation of graphite is spray coated onto a transparent conductive oxide substrate to realize a large area (>90 cm2) semi-transparent (transmittance 44%) counter-electrode (CE) replacing platinum, the standard CE material. The graphene-based CE is successfully integrated in a large-area (43.2 cm2 active area) DSSC module achieving a power conversion efficiency of 3.5%. The approach demonstrated here paves the way to all-printed, flexible, and transparent graphene-based large-area and cost-effective photovoltaic devices on arbitrary substrates.

  7. Oligothiophene-linked D-π-A type phenothiazine dyes for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Gao, Huan-Huan; Qian, Xing; Chang, Wen-Ying; Wang, Shan-Shan; Zhu, Yi-Zhou; Zheng, Jian-Yu

    2016-03-01

    Three novel phenothiazine dyes (JY31-33) featured oligothiophene π-bridge have been designed, synthesized and applied as photosensitizers for highly efficient dye-sensitized solar cells (DSSCs). The introduction of alkyl chains on oligothiophene π-bridge is found to significantly improve the open-circuit voltage of the resultant device. Phenothiazine bearing a 4-butoxyphenyl group as the secondary donor exhibits a stronger electron-donating ability and a positive acceleration on the short-circuit current density and open-circuit voltage. The dye JY33 containing a secondary donor and two alkyl chains finally gives a high efficiency of 7.48% under the 100 mW cm-2 simulated AM1.5 sunlight, with a short-circuit photocurrent density (Jsc) of 17.18 mA cm-2, an open-circuit photovoltage (Voc) of 742 mV and a fill factor (FF) of 0.59.

  8. Ultralong Rutile TiO2 Nanowire Arrays for Highly Efficient Dye-Sensitized Solar Cells.

    PubMed

    Li, Hailiang; Yu, Qingjiang; Huang, Yuewu; Yu, Cuiling; Li, Renzhi; Wang, Jinzhong; Guo, Fengyun; Jiao, Shujie; Gao, Shiyong; Zhang, Yong; Zhang, Xitian; Wang, Peng; Zhao, Liancheng

    2016-06-01

    Vertically aligned rutile TiO2 nanowire arrays (NWAs) with lengths of ∼44 μm have been successfully synthesized on transparent, conductive fluorine-doped tin oxide (FTO) glass by a facile one-step solvothermal method. The length and wire-to-wire distance of NWAs can be controlled by adjusting the ethanol content in the reaction solution. By employing optimized rutile TiO2 NWAs for dye-sensitized solar cells (DSCs), a remarkable power conversion efficiency (PCE) of 8.9% is achieved. Moreover, in combination with a light-scattering layer, the performance of a rutile TiO2 NWAs based DSC can be further enhanced, reaching an impressive PCE of 9.6%, which is the highest efficiency for rutile TiO2 NWA based DSCs so far. PMID:27097727

  9. Graphene-based large area dye-sensitized solar cell modules.

    PubMed

    Casaluci, Simone; Gemmi, Mauro; Pellegrini, Vittorio; Di Carlo, Aldo; Bonaccorso, Francesco

    2016-03-01

    We demonstrate spray coating of graphene ink as a viable method for large-area fabrication of graphene-based dye-sensitized solar cell (DSSC) modules. A graphene-based ink produced by liquid phase exfoliation of graphite is spray coated onto a transparent conductive oxide substrate to realize a large area (>90 cm(2)) semi-transparent (transmittance 44%) counter-electrode (CE) replacing platinum, the standard CE material. The graphene-based CE is successfully integrated in a large-area (43.2 cm(2) active area) DSSC module achieving a power conversion efficiency of 3.5%. The approach demonstrated here paves the way to all-printed, flexible, and transparent graphene-based large-area and cost-effective photovoltaic devices on arbitrary substrates. PMID:26883743

  10. Preparation and properties of low-cost graphene counter electrodes for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Wu, Qishuang; Shen, Yue; Wang, Qiandi; Gu, Feng; Cao, Meng; Wang, Linjun

    2013-12-01

    With the advantages of excellent electrical properties, high catalytic activity and low-cost preparation, Graphene is one of the most expected carbon materials to replace the expensive Pt as counter electrodes for dye-sensitized solar cells (DSSCs). In this paper, graphene counter electrodes were obtained by simple doctor-blade coating method on fluorine tin oxides (FTOs). The samples were investigated by X-ray diffraction (XRD), Raman spectroscopy and scanning electron microscope (SEM). Then the low-cost graphene electrodes were applied in typical sandwich-type DSSCs with TiO2 or ZnO as photoanodes, and their photoelectric conversion efficiency (η) were about 4.34% and 2.28%, respectively, which were a little lower than those of Pt electrodes but much higher than those of graphite electrodes. This law was consistent with the test results of electrochemical impedance spectroscopy (EIS). Low-cost graphene electrodes can be applied in DSSCs by process optimization.