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Sample records for nanocrystalline dye-sensitized solar

  1. Dye-sensitized nanocrystalline solar cells.

    PubMed

    Peter, Laurence M

    2007-06-01

    The basic physical and chemical principles behind the dye-sensitized nanocrystalline solar cell (DSC: also known as the Grätzel cell after its inventor) are outlined in order to clarify the differences and similarities between the DSC and conventional semiconductor solar cells. The roles of the components of the DSC (wide bandgap oxide, sensitizer dye, redox electrolyte or hole conductor, counter electrode) are examined in order to show how they influence the performance of the system. The routes that can lead to loss of DSC performance are analyzed within a quantitative framework that considers electron transport and interfacial electron transfer processes, and strategies to improve cell performance are discussed. Electron transport and trapping in the mesoporous oxide are discussed, and a novel method to probe the electrochemical potential (quasi Fermi level) of electrons in the DSC is described. The article concludes with an assessment of the prospects for future development of the DSC concept.

  2. 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.

  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. Photochemical solar cells based on dye-sensitization of nanocrystalline TiO2

    NASA Astrophysics Data System (ADS)

    Frank, A. J.; Gregg, B. A.; Grätzel, M.; Nozik, A. J.; Zaban, A.; Ferrere, S.; Schlichthörl, G.; Huang, S. Y.

    1997-04-01

    A new type of photovoltaic cell is described. It is a photoelectrochemical device that is based on the dye sensitization of thin (10-30 μm) films of TiO2 nanoparticles in contact with a non-aqueous liquid electrolyte. The cell is very simple to fabricate and, in principle, its color can be tuned through the visible spectrum, ranging from being completely transparent to black by changing the absorption characteristics of the dye; the photovoltage of the cell is not determined by the threshold energy for light absorption (bandgap) as in conventional photovoltaic cells based on solid-state semiconductors. The highest present efficiency of the dye-sensitized photochemical solar cell is about 11%. The cell has the potential to be a low-cost photovoltaic option. Unique applications include photovoltaic power windows and photoelectrochromic windows.

  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. 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

  7. Enhancing the photoelectric conversion of dye-sensitized solar cell via nitrogen-doped nanocrystalline titania electrode.

    PubMed

    Cheng, Ping; Lan, Tian; Yang, Haijun; Wang, Wanjun; Wu, Haixia; Deng, Changsheng; Dai, Xiaming; Guo, Shouwu

    2010-11-01

    A high efficient dye-sensitized solar cell (DSC) was fabricated using nitrogen-doped nanocrystalline titania(TiO2) photoanode. X-ray photoelectron spectroscopy (XPS), diffuse reflectance spectroscopy (DRS), X-ray powder diffraction (XRD), zeta potentials, nitrogen adsorption-desorption and elemental analysis experiments were employed to characterize the nitrogen-doped nanocrystalline TiO2 photoanode. An obvious enhancement of the optical absorption in the range of 380-550 nm was observed for nitrogen-doped TiO2, which was attributed to both the substitutional N and the chemisorbed N2 molecules. A conversion efficiency of 9.04% was obtained on the DSC based on nitrogen-doped TiO2 photoanode annealed in a flow of NH3 at 550 degrees C, with an increase of 15.6% improvement in comparison with pure TiO2 (7.82%). The mechanism for the enhanced photovoltaic performance was discussed.

  8. 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.

  9. 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.

  10. Enhanced Efficiency of Nanocrystalline Dye-Sensitized Solar Cells by Benzotriazole Doped Poly (ethylene oxide) Polymer Electrolyte

    NASA Astrophysics Data System (ADS)

    Ganesan, S.; Maruthamuthu, P.; Suthanthiraraj, S. Austin

    2010-10-01

    An organic nitrogenous compound benzotriazole was employed as a plasticizer in nanocrystalline dye-sensitized solar cells (nDSSC) incorporating a polymer electrolyte based on poly (ethylene oxide) (PEO). Detailed studies have been made on the structural and electrical characterization of the polymer electrolyte using X-ray diffraction (XRD), impedance spectroscopy and Scanning Electron Microscopy (SEM). Due to the coordinating and plasticizing effects of benzotriazole, enhanced ionic conductivity and reduced crystallinity of PEO polymer electrolyte accompanied by a better penetration of the same into the dye coated nanocrystalline TiO2 in order to enhance its efficiency were achieved. Based on the new polymer electrolyte, a nanocrystalline DSSC with a fillfactor of 0.53, an open-circuit voltage (Voc) of 695 mV, short-circuit current (Jsc) of 6.3 mAcm-2 and sun light to electricity conversion efficiency of 4.6% were obtained under AM 1.5 irradiation at 50 mWcm-2.

  11. 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.

  12. 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.

  13. The effect of optical properties on photovoltaic performance in dye-sensitized TiO2 nanocrystalline solar cells.

    PubMed

    Ji, Ya-Jun; Zhang, Ming-Dao; Cui, Jie-Hu; Zheng, He-Gen; Zhu, Jun-Jie

    2013-06-01

    In this study, well-crystallized TiO2 nanoparticles with average size of -20 nm were synthesized by hydrolysis of titania salt in aqueous medium. The effect of the optical properties of the obtained titania particles based thin films with different thickness on the photovoltaic performance of dye-sensitized solar cells were investigated. Differential thermal analysis/thermo-gravimetric analysis, scanning electron microscopy, transmission electron microscopy and X-ray diffraction were used to characterize the morphology, structure and crystal formation of the obtained samples. The optical properties such as reflectance and transmittance of the photoanodes with different thickness were systematically investigated. The reflectance property increased with increasing the film thickness, however, the transmittance property showed the opposite way. The improved scattering property with increasing the film thickness facilitated efficient utilization of solar spectrum, which was verified by incident photon-to-current conversion efficiency. The maximum energy conversion efficiency of 5.0% was achieved on photoelectrode film with 17.8 microm.

  14. 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.

  15. 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.

  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.

  17. Interplay between transparency and efficiency in dye sensitized solar cells.

    PubMed

    Tagliaferro, Roberto; Colonna, Daniele; Brown, Thomas M; Reale, Andrea; Di Carlo, Aldo

    2013-02-11

    In this paper we analyze the interplay between transparency and efficiency in dye sensitized solar cells by varying fabrication parameters such as the thickness of the nano-crystalline TiO(2) layer, the dye loading and the dye type. Both transparency and efficiency show a saturation trend when plotted versus dye loading. By introducing the transparency-efficiency plot, we show that the relation between transparency and efficiency is linear and is almost independent on the TiO(2) thickness for a certain thickness range. On the contrary, the relation between transparency and efficiency depends strongly on the type of the dye. Moreover, we show that co-sensitization techniques can be effectively used to access regions of the transparency-efficiency space that are forbidden for single dye sensitization. The relation found between transparency and efficiency (T&E) can be the general guide for optimization of Dye Solar Cells in building integration applications.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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,

  5. 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.

  6. 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.

  7. Aqueous dye-sensitized solar cells.

    PubMed

    Bella, Federico; Gerbaldi, Claudio; Barolo, Claudia; Grätzel, Michael

    2015-06-01

    Nowadays, dye-sensitized solar cells (DSSCs) are the most extensively investigated systems for the conversion of solar energy into electricity, particularly for implementation in devices where low cost and good performance are required. Nevertheless, a key aspect is still to be addressed, being considered strongly harmful for a long time, which is the presence of water in the cell, either in the electrolyte or at the electrode/electrolyte interface. Here comes the present review, in the course of which we try our best to address the highly topical role of water in DSSCs, trying to figure out if it is a poisoner or the keyword to success, by means of a thoroughly detailed analysis of all the established phenomena in an aqueous environment. Actually, in the last few years the scientific community has suddenly turned its efforts in the direction of using water as a solvent, as demonstrated by the amount of research articles being published in the literature. Indeed, by means of DSSCs fabricated with water-based electrolytes, reduced costs, non-flammability, reduced volatility and improved environmental compatibility could be easily achieved. As a result, an increasing number of novel electrodes, dyes and electrolyte components are continuously proposed, being highly challenging from the materials science viewpoint and with the golden thread of producing truly water-based DSSCs. If the initial purpose of DSSCs was the construction of an artificial photosynthetic system able to convert solar light into electricity, the use of water as the key component may represent a great step forward towards their widespread diffusion in the market. PMID:25864577

  8. 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

  9. Photoelectrochemical solar energy conversion by dye sensitization

    NASA Astrophysics Data System (ADS)

    Grätzel, M.

    1997-04-01

    The lecture describes the salient features of mesoscopic oxide semiconductor film and their electrochemical applications. In particular a molecular photovoltaic device is presented whose overall efficiency for AM 1.5 solar light to electricity at present attains 10-11%. The system is based on the sensitization of nanocrystalline oxide films by molecular charge transfer sensitizers. In analogy to photosynthesis, the new chemical solar cell separates light absorption and charge carrier transport processes. These cells exhibit a remarkable stability making practical applications feasible, the first products being targeted to supply electric power for consumer electronic devices. The mesoscopic oxide semiconductor films offer a number of other attractive research possibilities. Thus, a tandem device based on two superimposed layers with complementary light absorption in the visible range accomplishes the cleavage of water into hydrogen and oxygen with an overall efficiency of 4.5%.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. Dye-sensitized Solar Cells for Solar Energy Harvesting

    NASA Astrophysics Data System (ADS)

    Roy, M. S.; Deol, Y. S.; Kumar, Manish; Prasad, Narottam; Janu, Yojana

    2011-10-01

    Dye-sensitized solar cells (DSSCs) also known as Gratzel cells, have attracted the interests of researchers to a great extent because of its cost effective and easy manufacturing process without involving highly sophisticated lithographic technique and high cost raw materials as usually seen in conventional solar cell. Based on simple photo-electrochemical process, it has got immense potential in converting solar energy to electrical power in remote and desert area where the supply of conventional power is not possible. The overall peak power-production efficiency of dye-sensitized solar cells has been reported around 11 percent, so they are best suited to low-density applications and the price-to-performance ratio obtained through these solar cells is superior to others. DSSCs have ability to absorb even diffused sunlight and therefore work in cloudy whether as well without much impact over the efficiency. The present communication deals with a review of our work on DSSCs wherein we have used cost effective natural dyes/pigments as a sensitizer of nc-TiO2 and discussed about various key factors affecting the conversion efficiency of DSSC.

  15. 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.

  16. Characterising dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Tobin, Laura L.; O'Reilly, Thomas; Zerulla, Dominic; Sheridan, John T.

    2009-08-01

    With growing energy and environmental concerns due to fossil fuel depletion and global warming there is an increasing attention being attracted by alternative and/or renewable sources of power such as biomass, hydropower, geothermal, wind and solar energy. In today's society there is a vast and in many cases not fully appreciated dependence on electrical power for everyday life and therefore devices such as PV cells are of enormous importance. The more widely used and commercially available silicon (semiconductor) based cells currently have the greatest efficiencies, however the manufacturing of these cells is complex and costly due to the cost and difficulty of producing and processing pure silicon. One new direction being explored is the development of dye-sensitised solar cells (DSSC). The SFI Strategic Research Centre for Solar Energy Conversion is a new research cluster based in Ireland, formed with the express intention of bringing together industry and academia to produce renewable energy solutions. Our specific area of research is in biomimetic dye sensitised solar cells and their electrical properties. We are currently working to develop test equipment, and optoelectronic models describing the performance and behaviors of dye-sensitised solar cells (Grätzel Cells). In this paper we describe some of the background to our work and also some of our initial experimental results. Based on these results we intend to characterise the opto-electrical properties and bulk characteristics of simple dye-sensitised solar cells and then to proceed to test new cell compositions.

  17. New materials for hybrid dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Diacon, Aurel; Fara, Laurentiu; Cincu, Corneliu; Mitroi, Mihai Razvan; Zaharia, Catalin; Rusen, Edina; Boscornea, Cristian; Rosu, Constantin; Comaneci, Dragos

    2010-10-01

    This paper deals with the synthesis and characterization of new phtalocyanine based chromophores and new electrolyte for the fabrication of dye-sensitized solar cells (DSSCs) and hybrid dye-sensitized solar cells. The new phtalocyanines-based chromophores contain a different number of pending carboxy groups. The classic electrolyte was replaced by polymers that contain quaternary ammonium salts or polymer modified with PbS and CdS nanoparticles. This type of photovoltaic cells is not presented so far in the literature. Cell set-up involves TiO 2 deposition followed by dye adsorption and polymer film formation in the case of hybrid cells. The electrical parameters of the studied solar cells, namely the short-circuit current density Jsc and the open circuit voltage Voc, were measured.

  18. Energy Antenna for Efficient Dye-Sensitized Solar Cells.

    PubMed

    Kwon, Dong Yuel; Chang, Dong Min; Kim, Young Sik

    2015-02-01

    In this study, we investigated the effect of the placement of acceptor in dual donor based dye sensitizers (TPA-PTZ-CN, PTZ-TPA-CN). Triphenylamine (TPA) and phenothiazine (PTZ) are well known as electron donors and cyanoacetic acid (CN) is a known electron acceptor. The absorption spectrum of the dyes showed different form because of the different energy levels of molecular orbital (MO) of each dye and intramolecular energy transfer (EnT). The absorption spectrum of PTZ-TPA-CN was broader than that of TPA-PTZ-CN and its molar extinction coefficient was also higher than TPA-PTZ-CN. Because of its enhanced panchromatic absorption spectra, PTZ-TPA-CN showed better photovoltaic properties than the other dyes did. This work presents that optimizing the placement of acceptor in dual donor based dye would give good photovoltaic properties for dye-sensitized solar cells (DSSC).

  19. Enhanced conversion efficiency in dye-sensitized solar cells with nanocomposite photoanodes

    NASA Astrophysics Data System (ADS)

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

    2011-06-01

    Nanocomposite architectures consisting of conductive carbon nanotubes (CNTs) and nanocrystalline TiO2 films are prepared as photoanodes of dye-sensitized solar cells (DSCs). It is observed that both the electron transport time and electron lifetime decrease with CNT addition, implying that its incorporation is effective in enhancing the electro-conductivity of mesoscopic TiO2 contacts. To rectify CNT orientations, a parallel electric field is applied during the sample preparation, which gives rise to a significant enhancement in the energy conversion efficiency of resultant DSCs. Electrochemical impedance spectroscopy clarifies the photoelectrochemical processes, with enhanced contribution to the efficient electron transport, arising from the increased CNT orientation.

  20. Brief overview of dye-sensitized solar cells.

    PubMed

    Hagfeldt, Anders

    2012-01-01

    Dye-sensitized solar cells (DSC) are based on molecular and nanometer-scale components. Record cell efficiencies of 12%, promising stability data and means of energy-efficient production methods have been accomplished. As selling points for the DSC technology the prospect of low-cost investments and fabrication are key features. DSCs offer the possibilities to design solar cells with a large flexibility in shape, color, and transparency. The basic principles of the operation of DSC, the state-of-the-art as well as the potentials for future development are described.

  1. 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.

  2. 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.

  3. 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.

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

    PubMed

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

    2016-05-04

    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.

  5. 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

  6. The renaissance of dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Hardin, Brian E.; Snaith, Henry J.; McGehee, Michael D.

    2012-03-01

    Several recent major advances in the design of dyes and electrolytes for dye-sensitized solar cells have led to record power-conversion efficiencies. Donor-pi-acceptor dyes absorb much more strongly than commonly employed ruthenium-based dyes, thereby allowing most of the visible spectrum to be absorbed in thinner films. Light-trapping strategies are also improving photon absorption in thin films. New cobalt-based redox couples are making it possible to obtain higher open-circuit voltages, leading to a new record power-conversion efficiency of 12.3%. Solid-state hole conductor materials also have the potential to increase open-circuit voltages and are making dye-sensitized solar cells more manufacturable. Engineering the interface between the titania and the hole transport material is being used to reduce recombination and thus attain higher photocurrents and open-circuit voltages. The combination of these strategies promises to provide much more efficient and stable solar cells, paving the way for large-scale commercialization.

  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. 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).

  9. 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.

  10. 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

  11. 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

  12. Dna-Enhanced Dye-Sensitized Solar Cells

    NASA Astrophysics Data System (ADS)

    Pollum, Marvin; Crespo-Hernandez, Carlos E.

    2013-06-01

    Dye-sensitized solar cells (DSSCs) are a promising alternative to the current silicon solar cell technologies. DSSCs have a lower manufacturing cost, can be made to be flexible, semi-transparent, and in any variety of colors for aesthetic applications. Despite these advantageous properties, the stability and power conversion efficiency of DSSCs are still lacking. Recently, we have shown that the adsorption of DNA onto the semiconductor surface of a typical DSSC improves its overall performance. Structure-function analysis, in conjunction with steady-state and time-resolved spectroscopic studies, are currently being done to understand this phenomenon and to uncover the mechanism by which DNA boosts the overall performance of DSSCs. This new knowledge is expected to facilitate the rational design of DSSCs that exhibit higher power conversion efficiency than those currently available.

  13. 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.

  14. Molecular engineering of carbazole functionalized ruthenium dyes for efficient dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Nguyen, Hong Minh; Vu, Dinh Lam; Nghia Nguyen, Duc

    2011-12-01

    A new ruthenium complex, coded HMP-12, incorporating an antenna ligand composed of the sequential connection of a conjugated segment and carbazole hole-transport moiety was synthesized. This dye exhibits a lower energy metal-to-ligand charge transfer (MLCT) band centered at 536 nm with a high molar absorption coefficient of 21.43×103 M‑1 cm‑1. Nanocrystalline ZnO dye-sensitized solar cells employing HMP-12 show good conversion efficiency (4.46%). It was found that the difference in light-harvesting properties between Rut-B1, HMP-11 and HMP-12 is associated mainly with dye structure. The power conversion efficiency of solar cells based on HMP-11 is 4.11% while the Rut-B1 delivered a lower efficiency of 3.57% under the same device fabrication and measuring conditions.

  15. 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

  16. 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.

  17. 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%.

  18. 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.

  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. 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.

  1. Rapid Dye Regeneration Mechanism of Dye-Sensitized Solar Cells.

    PubMed

    Jeon, Jiwon; Park, Young Choon; Han, Sang Soo; Goddard, William A; Lee, Yoon Sup; Kim, Hyungjun

    2014-12-18

    During the light-harvesting process of dye-sensitized solar cells (DSSCs), the hole localized on the dye after the charge separation yields an oxidized dye, D(+). The fast regeneration of D(+) using the redox pair (typically the I(-)/I3(-) couple) is critical for the efficient DSSCs. However, the kinetic processes of dye regeneration remain uncertain, still promoting vigorous debates. Here, we use molecular dynamics simulations to determine that the inner-sphere electron-transfer pathway provides a rapid dye regeneration route of ∼4 ps, where penetration of I(-) next to D(+) enables an immediate electron transfer, forming a kinetic barrier. This explains the recently reported ultrafast dye regeneration rate of a few picoseconds determined experimentally. We expect that our MD based comprehensive understanding of the dye regeneration mechanism will provide a helpful guideline in designing TiO2-dye-electrolyte interfacial systems for better performing DSSCs. PMID:26273975

  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.

  3. 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.

  4. 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.

  5. 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

  6. 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.

  7. Sensitizers containing donor cascade and rhodanine-3-acetic acid moieties for dye-sensitized solar cells

    SciTech Connect

    Wu, Quan-Ping; Zhang, Lu; Liang, Mao; Sun, Zhe; Xue, Song

    2011-01-15

    Three organic dyes with D-{pi}-D-{pi}-A structure based on triarylamine, dimethylarylamine, and rhodanine-3-acetic acid moieties are designed and synthesized. Incorporating thiophene moieties into the system affords sensitizers with high molar extinction coefficients. These dyes were applied into nanocrystalline TiO{sub 2} dye-sensitized solar cells through standard operations. For a typical device the maximal monochromatic incident photon-to-current conversion efficiency (IPCE) can reach 73%, with a short-circuit photocurrent density (J{sub sc}) of 7.3 mA/cm{sup 2}, an open-circuit voltage (V{sub oc}) of 636 mV, and a fill factor (ff) of 0.61, corresponding to an overall conversion efficiency ({eta}) of 2.86%. (author)

  8. 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%.

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

    PubMed

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

    2015-02-25

    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%.

  10. Steady-state transport characteristics of photoconductor based on dye-sensitized solar cell

    NASA Astrophysics Data System (ADS)

    Xu, J.; Wang, X. Q.; Lu, Y. M.; Liu, Z. Y.; Cai, C. B.

    2010-06-01

    In the present work, three photoconductors based on dye-sensitized nanocrystalline TiO2 are designed with two dye-sensitized solar cells (DSSCs) connected together using a common counter electrode but different connecting approaches for electrolytes and TiO2 film. DC steady-state transport measurements on source and drain corresponding to the photoanodes of two constituent DSSC units, respectively, show that the three photoconductive devices exhibit similar transistor characteristics, regardless of their different electronic connecting approaches. It is revealed that their transport characteristics are determined by the effective areas of the photoanode and the counter electrode, rather than the connection of electrolytes and TiO2 film. Furthermore, it is demonstrated that the dominant factor of transport behavior is the imbalanced energy band caused by the match of intrinsic potential within two constituent DSSC units. Due to unique mechanism and relatively simple fabrication process, the present phototransistors have potentials for an economical and efficient light-operated switch as well as an emerged optical communication device.

  11. Bipyridyl cobalt complex mediators in dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Scott, Michael J.

    Dye-sensitization of semiconductor substrates allows for efficient charge injection into the semiconductor conduction band. Dye-sensitized solar cells (DSSCs) exploit this for conversion of light into electrical energy. By employing mesoporous TiO2 a significant portion of visible light can be absorbed. The mesoporous TiO2, deposited on a transparent conducting oxide (TCO) medium, constitutes the photoanode of the DSSC. A wide range of materials may be used as a cathode. A redox electrolyte solution completes the cell. Typically, the I-/I3- redox couple has been employed in DSSCs. The use of bipyridyl cobalt complexes allows for tuning of the cell's electrochemistry, exploration of diverse cathode materials, and investigation of mediator solution additives. Cobalt complexes with alkyl, ester, and amide functionalities were considered throughout this body of work. The cobalt complexes were investigated on the basis of time dependence and electrode dependence. The cobalt complexes are stable for at least a period of one week when dissolved in gamma-butyrolactone. Gold, carbon and modified TCO cathodes perform well in cells employing the alkyl substituted complex. Gold cathodes alone provide the best performance with cells employing the ester and amide substituted complex. An optically transparent cathode was developed for use in stacked DSSCs, allowing light that is not absorbed by the first DSSC in a stack to be absorbed by a second cell. A spectrally complementary dye in the second cell extends the light absorption to longer wavelengths. Spatial current images were obtained to investigate the local current behavior of cobalt mediated cells. Intentional electrode damage was visualized, and the effects of increased pressure on the cell were discussed. The use of phenothiazine (PTZ) moieties as co-mediators in cobalt mediated DSSCs was investigated. An anionic PTZ salt was most effective at reducing the photo-oxidized sensitizing dye. This PTZ salt enhanced the

  12. 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

  13. 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

  14. Cubic titanium dioxide photoanode for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Chae, Jinho; Kang, Misook

    Following from the recently evolved concept of significantly improving the photovoltaic efficiency in dye-sensitized solar cells (DSSCs) by reducing the loss of electrons on the spherical surface of titanium dioxide, this study examines the synthesis of cubic TiO 2 with a special morphology to overcome this electron loss and investigates its application to DSSCs. Cubic TiO 2 is synthesized by an advanced rapid hydrothermal method, with the addition of an amine species additive. Transmission electron microscopy (TEM) images confirm the cubic shape of the TiO 2 particles with a diameter less than 5-10 nm. Using N719 dye under illumination with 100 mW cm -2 simulated sunlight, the application of cubic TiO 2 to DSSCs affords an energy conversion efficiency of approximately 9.77% (4.0-μm thick TiO 2 film), which is considerably enhanced compared with that achieved using a commercial, spherical TiO 2. Electrostatic force microscopy (EFM) and impedance analyses reveal that the electrons are transferred more rapidly to the surface of a cubic TiO 2 film than on a spherical TiO 2 film.

  15. 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.

  16. 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

  17. Photoassisted spatially resolved STM measurements of dye-sensitized nanocrystalline TiO2 films

    NASA Astrophysics Data System (ADS)

    Jacobsen, Volker; Knoll, Wolfgang; Kreiter, Maximilian; Dürr, Michael; Yasuda, Akio; Nelles, Gabriele

    2007-04-01

    Photoassisted scanning tunneling microscopy was used to investigate photoinduced currents in a dye-sensitized nanoporous TiO2 network in a locally resolved experiment. The light-induced tunneling current (LITC) was studied with respect to its dependence on the modulation frequency of the exciting light as well as on the externally applied bias. By this, two main contributions to the LITC were identified and assigned to both a tunneling current of photoelectrons from the TiO2 conduction band to the tip and a tunneling current driven by a photoinduced change of the voltage drop over the tunneling gap. Additionally, the observed frequency dependence of the LITC components is in agreement with the time scales expected for a hopping transport via localized energy states. Lateral variations in the LITC signal are found between aggregates of TiO2 particles, directly reflecting different electronic properties. These results might be important for further optimization of porous materials in applications such as dye-sensitized solar cells.

  18. Effects of Dye Structure in Dye Sensitized Solar Cells

    NASA Astrophysics Data System (ADS)

    Hoskins, Anna R.

    Dye sensitized solar cells (DSSCs) are photovoltaic devices that may compete with standard silicon solar cells due to their ease of construction and lower cost [32]. Ruthenium dye structures, such as N3 (Ru -- (4,4' -- dicarboxylic acid -- 2,2' -- bipyridine)2(NCS)2), have shown promise for collection efficiencies near silicon photovoltaic levels [20, 33]. DSSCs have not achieved the reproducibility and maximum efficiency of silicon solar cells [33, 34]. Altering ligands on the dye molecules may affect the energies of light that are absorbed by the DSSC. Photovoltaic testing, including current versus voltage tests, of DSSCs with both narrow band monochromated light sources and broadband (AM1.5 solar simulator) allows comparison between maximum efficiency, short-circuit current, open circuit voltage, and spectral response (SR) for the dye molecules. By studying how the efficiency and power output change with different dye structures, the nature of how to increase efficiency of the DSSC can be addressed. Conjugation length of the ligands in ruthenium dye molecules can be shown, through square-well and Huckel theory calculations, to have a role in changing the HOMO-LUMO gap of the molecules and the absorption of specific wavelengths of light by the DSSC. The efficiency, max power, short circuit current, open circuit voltage, and SR were all measured for the DSSCs at wavelengths from 350 nm to 690 nm using a monochromated light source. Measurements taken at 20 nm steps reveal trends in the photon acceptance for dye molecules that can be linked to the conjugation length of the ligands in the dye through the SR. The change in the SR centroid and UV-VIS measurements indicate a trend toward increasing optimal wavelength with increasing conjugation length in the dye molecules; however these trends are not as pronounced as theoretical calculations for the dyes. This difference in wavelength shift occurs due to the theoretical calculations accounting for only the ligands

  19. 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.

  20. 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.

  1. Effect of Substituents in Catechol Dye Sensitizers on Photovoltaic Performance of Type II Dye-Sensitized Solar Cells.

    PubMed

    Ooyama, Yousuke; Kanda, Masahiro; Uenaka, Koji; Ohshita, Joji

    2015-10-01

    In order to provide a direction in molecular design of catechol (Cat) dyes for type II dye-sensitized solar cells (DSSCs), the dye-to-TiO2 charge-transfer (DTCT) characteristics of Cat dyes with various substituents and their photovoltaic performance in DSSCs are investigated. The Cat dyes with electron-donating or moderately electron-withdrawing substituents exhibit a broad absorption band corresponding to DTCT upon binding to TiO2 films, whereas those with strongly electron-withdrawing substituents exhibit weak DTCT. This study indicates that the introduction of a moderately electron-withdrawing substituent on the Cat moiety leads to not only an increase in the DTCT efficiency, but also the retardation of back electron transfer. This results in favorable conditions for the type II electron-injection pathway from the ground state of the Cat dye to the conduction band of the TiO2 electrode by the photoexcitation of DTCT bands.

  2. 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.

  3. A Hybrid Tandem Solar Cell Combining a Dye-Sensitized and a Polymer Solar Cell.

    PubMed

    Shao, Zhipeng; Chen, Shuanghong; Zhang, Xuhui; Zhu, Liangzheng; Ye, Jiajiu; Dai, Songyuan

    2016-06-01

    A hybrid tandem solar cell was assambled by connecting a dye sensitized solar cell and a polymer solar cell in series. A N719 sensitized TiO2 was used as photocathode in dye-sensitized subcell, and a MEH-PPV/PCBM composite was used as active layer in the polymer subcell. The polymer subcell fabricated on the counter electrode of the dye sensitized solar cell. A solution processed TiO(x) layer was used as electron collection layer of the polymer sub cell and the charge recombination layer. The effects of the TiO(x) interlayer and the spectral overlap between the two sub cells have been studied and optimized. The results shows that a proper thickness of the TiO(x) layer is needed for tandem solar cells. Thick TiO(x) will enhance the series resistance, but too thin TiO(x), layer will damage the hole blocking effect and its hydrophilic. The resulting optimized tandem solar cells exhibited a power conversion efficiency of 1.28% with a V(oc) of 0.95 V under simulated 100 mW cm(-2) AM 1.5 illumination. PMID:27427604

  4. A Hybrid Tandem Solar Cell Combining a Dye-Sensitized and a Polymer Solar Cell.

    PubMed

    Shao, Zhipeng; Chen, Shuanghong; Zhang, Xuhui; Zhu, Liangzheng; Ye, Jiajiu; Dai, Songyuan

    2016-06-01

    A hybrid tandem solar cell was assambled by connecting a dye sensitized solar cell and a polymer solar cell in series. A N719 sensitized TiO2 was used as photocathode in dye-sensitized subcell, and a MEH-PPV/PCBM composite was used as active layer in the polymer subcell. The polymer subcell fabricated on the counter electrode of the dye sensitized solar cell. A solution processed TiO(x) layer was used as electron collection layer of the polymer sub cell and the charge recombination layer. The effects of the TiO(x) interlayer and the spectral overlap between the two sub cells have been studied and optimized. The results shows that a proper thickness of the TiO(x) layer is needed for tandem solar cells. Thick TiO(x) will enhance the series resistance, but too thin TiO(x), layer will damage the hole blocking effect and its hydrophilic. The resulting optimized tandem solar cells exhibited a power conversion efficiency of 1.28% with a V(oc) of 0.95 V under simulated 100 mW cm(-2) AM 1.5 illumination.

  5. Starburst triarylamine based dyes for efficient dye-sensitized solar cells.

    PubMed

    Ning, Zhijun; Zhang, Qiong; Wu, Wenjun; Pei, Hongcui; Liu, Bo; Tian, He

    2008-05-16

    We report here on the synthesis and photophysical/electrochemical properties of a series of novel starburst triarylamine-based organic dyes (S1, S2, S3, and S4) as well as their application in dye-sensitized nanocrystalline TiO2 solar cells (DSSCs). For the four designed dyes, the starburst triarylamine group and the cyanoacetic acid take the role of electron donor and electron acceptor, respectively. It was found that the introduction of starburst triarylamine group to form the D-D-pi-A configuration brought about superior performance over the simple D-pi-A configuration, in terms of bathochromically extended absorption spectra, enhanced molar extinction coefficients and better thermo-stability. Moreover, the HOMO and LUMO energy levels tuning can be conveniently accomplished by alternating the donor moiety, which was confirmed by electrochemical measurements and theoretical calculations. The DSSCs based on the dye S4 showed the best photovoltaic performance: a maximum monochromatic incident photon-to-current conversion efficiency (IPCE) of 85%, a short-circuit photocurrent density (J(sc)) of 13.8 mA cm(-2), an open-circuit photovoltage (V(oc)) of 0.63 V, and a fill factor (ff) of 0.69, corresponding to an overall conversion efficiency of 6.02% under 100 mW cm(-2) irradiation. This work suggests that the dyes based on starburst triphenylamine donor are promising candidates for improvement of the performance of the DSSCs.

  6. Mesoporous submicrometer TiO(2) hollow spheres as scatterers in dye-sensitized solar cells.

    PubMed

    Dadgostar, Shabnam; Tajabadi, Fariba; Taghavinia, Nima

    2012-06-27

    Hierarchical submicrometer TiO2 hollow spheres with outer diameter of 300-700 nm and shell thickness of 200 nm are synthesized by liquid phase deposition of TiO2 over carbon microspheres as sacrificial templates. The final TiO2 hollow spheres are applied as a scattering layer on top of a transparent nanocrystalline TiO2 film, serving as the photoanode of a dye-sensitized solar cell (DSC). In addition to efficient light scattering, the mesoporous structure of TiO2 hollow spheres provides a high surface area, 74 m(2)/g, which allows for higher dye loading. This dual functioning suggests that TiO2 hollow spheres may be good replacements for conventional TiO2 spheres as scatterers in DSCs. A high efficiency of 8.3% is achieved with TiO2 hollow spheres, compared with 6.0% for the electrode with 400 nm spherical TiO2 scatterers, at identical conditions. PMID:22606936

  7. 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.

  8. Mechanism of degradation of electrolyte solutions for dye-sensitized solar cells under ultraviolet light irradiation

    NASA Astrophysics Data System (ADS)

    Nakajima, Shohei; Katoh, Ryuzi

    2015-01-01

    We studied the mechanism of the degradation of I-/I3--containing electrolyte solutions for dye-sensitized solar cells under UV light irradiation. The yellow electrolyte solutions underwent achromatization during irradiation, indicating the reduction of I3-. We propose a mechanism involving the production of holes in TiO2, reaction of the holes with solvent molecules, and subsequent reduction of I3- by electrons remaining in the TiO2. Although the quantum yield of the photodegradation reaction is estimated to be low (3 × 10-3), this reaction can nevertheless be expected to affect the long-term stability of dye-sensitized solar cell devices.

  9. 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.

  10. Dye-sensitized solar cells employing a single film of mesoporous TiO2 beads achieve power conversion efficiencies over 10%.

    PubMed

    Sauvage, Frédéric; Chen, Dehong; Comte, Pascal; Huang, Fuzhi; Heiniger, Leo-Philipp; Cheng, Yi-Bing; Caruso, Rachel A; Graetzel, Michael

    2010-08-24

    Dye-sensitized solar cells employing mesoporous TiO(2) beads have demonstrated longer electron diffusion lengths and extended electron lifetimes over Degussa P25 titania electrodes due to the well interconnected, densely packed nanocrystalline TiO(2) particles inside the beads. Careful selection of the dye to match the dye photon absorption characteristics with the light scattering properties of the beads have improved the light harvesting and conversion efficiency of the bead electrode in the dye-sensitized solar cell. This has resulted in a solar to electric power conversion efficiency (PCE) of greater than 10% (10.6% for Ru(II)-based dye C101 and 10.7% using C106) for the first time using a single screen-printed titania layer cell construction (that is, without an additional scattering layer).

  11. 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.

  12. 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.

  13. Oligocarbazole-based chromophores for efficient thin-film dye-sensitized solar cells.

    PubMed

    De Sousa, Samuel; Olivier, Céline; Ducasse, Laurent; Le Bourdon, Gwenaëlle; Hirsch, Lionel; Toupance, Thierry

    2013-06-01

    Carb your enthusiasm: Carbazole-based sensitizers with high extinction coefficients are synthesized for application in dye-sensitized solar cells (DSCs). The dyes perform efficiently with both iodine and cobalt electrolytes, showing power conversion efficiencies of up to 5.8% on TiO₂ films of 15 μm thickness, and retaining 90% of their efficiency in devices with thinner films.

  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.

  15. Monolithic-Structured Single-Layered Textile-Based Dye-Sensitized Solar Cells

    PubMed Central

    Yun, Min Ju; Cha, Seung I.; Kim, Han Seong; Seo, Seon Hee; Lee, Dong Y.

    2016-01-01

    Textile-structured solar cells are frequently discussed in the literature due to their prospective applications in wearable devices and in building integrated solar cells that utilize their flexibility, mechanical robustness, and aesthetic appearance, but the current approaches for textile-based solar cells—including the preparation of fibre-type solar cells woven into textiles—face several difficulties from high friction and tension during the weaving process. This study proposes a new structural concept and fabrication process for monolithic-structured textile-based dye-sensitized solar cells that are fabricated by a process similar to the cloth-making process, including the preparation of wires and yarns that are woven for use in textiles, printed, dyed, and packaged. The fabricated single-layered textile-based dye-sensitized solar cells successfully act as solar cells in our study, even under bending conditions. By controlling the inter-weft spacing and the number of Ti wires for the photoelectrode conductor, we have found that the performance of this type of dye-sensitized solar cell was notably affected by the spacing between photoelectrodes and counter-electrodes, the exposed areas of Ti wires to photoelectrodes, and photoelectrodes’ surface morphology. We believe that this study provides a process and concept for improved textile-based solar cells that can form the basis for further research. PMID:27708359

  16. Monolithic-Structured Single-Layered Textile-Based Dye-Sensitized Solar Cells

    NASA Astrophysics Data System (ADS)

    Yun, Min Ju; Cha, Seung I.; Kim, Han Seong; Seo, Seon Hee; Lee, Dong Y.

    2016-10-01

    Textile-structured solar cells are frequently discussed in the literature due to their prospective applications in wearable devices and in building integrated solar cells that utilize their flexibility, mechanical robustness, and aesthetic appearance, but the current approaches for textile-based solar cells—including the preparation of fibre-type solar cells woven into textiles—face several difficulties from high friction and tension during the weaving process. This study proposes a new structural concept and fabrication process for monolithic-structured textile-based dye-sensitized solar cells that are fabricated by a process similar to the cloth-making process, including the preparation of wires and yarns that are woven for use in textiles, printed, dyed, and packaged. The fabricated single-layered textile-based dye-sensitized solar cells successfully act as solar cells in our study, even under bending conditions. By controlling the inter-weft spacing and the number of Ti wires for the photoelectrode conductor, we have found that the performance of this type of dye-sensitized solar cell was notably affected by the spacing between photoelectrodes and counter-electrodes, the exposed areas of Ti wires to photoelectrodes, and photoelectrodes’ surface morphology. We believe that this study provides a process and concept for improved textile-based solar cells that can form the basis for further research.

  17. 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.

  18. 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

  19. Fully printable transparent monolithic solid-state dye-sensitized solar cell with mesoscopic indium tin oxide counter electrode.

    PubMed

    Yang, Ying; Ri, Kwangho; Rong, Yaoguang; Liu, Linfeng; Liu, Tongfa; Hu, Min; Li, Xiong; Han, Hongwei

    2014-09-01

    We present a new transparent monolithic mesoscopic solid-state dye-sensitized solar cell based on trilamellar films of mesoscopic TiO2 nanocrystalline photoanode, a ZrO2 insulating layer and an indium tin oxide counter electrode (ITO-CE), which were screen-printed layer by layer on a single substrate. When the thickness of the ITO-CE was optimized to 2.1 μm, this very simple and fully printable solid-state DSSC with D102 dye and spiro-OMeTAD hole transport materials presents efficiencies of 1.73% when irradiated from the front side and 1.06% when irradiated from the rear side under a standard simulated sunlight condition (AM 1.5 Global, 100 mW cm(-2)). Higher parameters could be expected with a better transparent mesoscopic counter electrode and hole conductor for the printable monolithic mesoscopic solid-state DSSC.

  20. 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.

  1. 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.

  2. 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.

  3. 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

  4. Flexible Dye-Sensitized Solar Cell Based on Vertical ZnO Nanowire Arrays

    PubMed Central

    2011-01-01

    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. PMID:27502660

  5. Charge dynamics in new architectures for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Martinson, Alex Brandon Fletcher

    The promise of a clean, renewable, and abundant energy supply make the efficient conversion of solar energy to electricity a compelling scientific and societal goal. In the following chapters, I will describe my efforts to advance one class of photovoltaic technology, dye-sensitized solar cells, by demonstration and characterization of unexplored device architectures. Chapter 1 provides an introduction to the origin of solar energy conversion and the fundamentals of dye-sensitized solar cells. An understanding of device operation through charge dynamics facilitates a survey of the state of the art in addition to predictions for promising future directions. Chapter 2 elucidates the electron transport and interception dynamics in ZnO nanorod array based dye-sensitized solar cells. The data presented suggest that the study of alternative photoanode architectures is a viable means of improving device performance and understanding. Chapter 3 introduces a new photoanode design in which anodic aluminum oxide and atomic layer deposition are utilized to fabricate oriented arrays of electrically interconnected semiconductor nanotubes. The viability of these structures as dye-sensitized electrodes is demonstrated by characterization of their morphology, light harvesting efficiency, and photovoltaic performance. Chapter 4 builds upon the successful implementation of nanotube based dye-sensitized solar cells by quantifying charge dynamics through electrochemical impedance spectroscopy. Fitting the impedance data to an appropriate equivalent circuit establishes ZnO nanotubes as the most effective architecture for rapid electron collection to date. Chapter 5 expands the synthetic palette of atomic layer deposition to include transparent conducting oxides that may be grown on high aspect ratio templates. Understanding and optimizing the growth mechanism of two versatile systems enables the structures to be presented in the final chapter. Chapter 6 concludes with a presentation of

  6. 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.

  7. 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.

  8. DCM-based organic dyes with electron donating groups for dye-sensitized solar cells.

    PubMed

    Kim, Joo Young; Yoon, Seung Soo; Kim, Young Sik

    2014-07-01

    Herein, 4-(dicyanomethylene)-2-methyl-6-[p-(dimethylamino)styryl]-4H-pyran (DCM)-based dyes with electron donating groups were designed and their electronic and optical properties were investigated theoretically for dye-sensitized solar cells (DSSCs). Among the dyes, the D1 and D2 dyes were composed of single electron donating group and the D3 and D4 dyes composed of dual donating group. We performed DFT/TDDFT calculations to get insight into the factors responsible for photovoltaic properties as dye sensitizers. It showed that all the dyes in this work are available as dye sensitizers from the energy consideration compared to TiO2 electrode and iodide electrolyte. It also showed that the D3 and D4 dyes produced additional absorption bands by the introduction of dual donor in absorption spectra and the absorption band of the D4 dye is more red-shifted than that of the D3 dye. It is attributed to the fact that the M2 (a coumarin derivative) moiety with stronger electron withdrawing ability stabilized its LUMO level. In terms of molar extinction coefficient and panchromatic feature, we suggest that the D4 dye would show better performance than other dyes in the present study as a dye sensitizer for DSSCs.

  9. Review on nanostructured semiconductors for dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Prakash, T.

    2012-06-01

    Nanostructured semiconductors with different morphologies are used widely in various applications in order to enhance their technological advancements compared with the bulk sample. This flourishing nanoscience field has enabled rapid developments that have created numerous opportunities for scienctific advancements with various devices. Considering large environmental impacts such as global warming, problems of nuclear waste storage and nuclear accidents, there is an urgent need for environmentally sustainable energy technologies such as solar cells and fuel cells. In the present paper, the role of nanostructured semiconductors in dyesensitized solar cells (DSSCs) is reviewed entensively. The review discusses the present developmental prospects of DSSCs and the problems associated with its layer materials and propose a method of overcoming these problems.

  10. 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.

  11. 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.

  12. 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.

  13. 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%.

  14. 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%.

  15. Metal substrate based electrodes for flexible dye-sensitized solar cells: fabrication methods, progress and challenges.

    PubMed

    Balasingam, Suresh Kannan; Kang, Man Gu; Jun, Yongseok

    2013-12-21

    A step towards commercialization of dye-sensitized solar cells (DSSCs) requires more attention to engineering aspects, such as flexibility, the roll to roll fabrication process, the use of cost effective materials, etc. In this aspect, advantages of flexible DSSCs attracted many researchers to contemplate the transparent conducting oxide coated flexible plastic substrates and the thin metallic foils. In this feature article, the pros and cons of these two kinds of substrates are compared. The flexible dye-sensitized solar cells fabricated using metal substrates are briefly discussed. The working electrodes of DSSCs fabricated on various metal substrates, their fabrication methods, the effect of high temperature calcination and drawbacks of back illumination are reviewed in detail. A few reports on the flexible metal substrate based counter electrodes that could be combined with the plastic substrate based working electrodes are also covered at the end. PMID:24196211

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

    PubMed

    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.

  17. Dye-sensitized solar cells with 13% efficiency achieved through the molecular engineering of porphyrin sensitizers.

    PubMed

    Mathew, Simon; Yella, Aswani; Gao, Peng; Humphry-Baker, Robin; Curchod, Basile F E; Ashari-Astani, Negar; Tavernelli, Ivano; Rothlisberger, Ursula; Nazeeruddin, Md Khaja; Grätzel, Michael

    2014-03-01

    Dye-sensitized solar cells have gained widespread attention in recent years because of their low production costs, ease of fabrication and tunable optical properties, such as colour and transparency. Here, we report a molecularly engineered porphyrin dye, coded SM315, which features the prototypical structure of a donor-π-bridge-acceptor and both maximizes electrolyte compatibility and improves light-harvesting properties. Linear-response, time-dependent density functional theory was used to investigate the perturbations in the electronic structure that lead to improved light harvesting. Using SM315 with the cobalt(II/III) redox shuttle resulted in dye-sensitized solar cells that exhibit a high open-circuit voltage VOC of 0.91 V, short-circuit current density JSC of 18.1 mA cm(-2), fill factor of 0.78 and a power conversion efficiency of 13%.

  18. Dye-sensitized solar cells with 13% efficiency achieved through the molecular engineering of porphyrin sensitizers

    NASA Astrophysics Data System (ADS)

    Mathew, Simon; Yella, Aswani; Gao, Peng; Humphry-Baker, Robin; Curchod, Basile F. E.; Ashari-Astani, Negar; Tavernelli, Ivano; Rothlisberger, Ursula; Nazeeruddin, Md. Khaja; Grätzel, Michael

    2014-03-01

    Dye-sensitized solar cells have gained widespread attention in recent years because of their low production costs, ease of fabrication and tunable optical properties, such as colour and transparency. Here, we report a molecularly engineered porphyrin dye, coded SM315, which features the prototypical structure of a donor-π-bridge-acceptor and both maximizes electrolyte compatibility and improves light-harvesting properties. Linear-response, time-dependent density functional theory was used to investigate the perturbations in the electronic structure that lead to improved light harvesting. Using SM315 with the cobalt(II/III) redox shuttle resulted in dye-sensitized solar cells that exhibit a high open-circuit voltage VOC of 0.91 V, short-circuit current density JSC of 18.1 mA cm-2, fill factor of 0.78 and a power conversion efficiency of 13%.

  19. 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.

  20. 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

  1. 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

  2. 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

  3. 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.

  4. Block copolymer morphologies in dye-sensitized solar cells: probing the photovoltaic structure-function relation.

    PubMed

    Crossland, Edward J W; Nedelcu, Mihaela; Ducati, Caterina; Ludwigs, Sabine; Hillmyer, Marc A; Steiner, Ullrich; Snaith, Henry J

    2009-08-01

    We integrate mesostructured titania arrays into dye-sensitized solar cells by replicating ordered, oriented one-dimensional (1D) columnar and three-dimensional (3D) bicontinuous gyroid block copolymer phases. The solar cell performance, charge transport, and recombination are investigated. We observe faster charge transport in 1D "wires" than through 3D gyroid arrays. However, owing to their structural instability, the surface area of the wire arrays is low, inhibiting the solar cell performance. The gyroid morphology, on the other hand, outperforms the current state-of-the-art mesoporous nanoparticle films.

  5. 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

  6. 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.

  7. 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.

  8. 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 %.

  9. 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.

  10. Near infrared organic semiconducting materials for bulk heterojunction and dye-sensitized solar cells.

    PubMed

    Singh, Surya Prakash; Sharma, G D

    2014-06-01

    Dye sensitized solar cells (DSSCs) and bulk heterojunction (BHJ) solar cells have been the subject of intensive academic interest over the past two decades, and significant commercial effort has been directed towards this area with the vison of developing the next generation of low cost solar cells. Materials development has played a vital role in the dramatic improvement of both DSSC and BHJ solar cell performance in the recent years. Organic conjugated polymers and small molecules that absorb solar light in the visible and near infrared (NIR) regions represent a class of emering materials and show a great potential for the use of different optoelectronic devices such as DSSCs and BHJ solar cells. This account describes the emering class of near infrared (NIR) organic polymers and small molecules having donor and acceptors units, and explores their potential applications in the DSSCs and BHJ solar cells.

  11. Improving the efficiency of a dye-sensitized solar cell with a reflex condenser system.

    PubMed

    Lee, Sang-min; Lee, Seung-jun; Choi, Soo-chang; Kim, Jong-min; Kim, Jong-man; Kim, Soo-hyung; Lee, Deug-woo

    2012-11-01

    Dye-sensitized solar cells (DSSCs) are inexpensive to manufacture and easy to process in comparison with silicone solar cells, but they are difficult to commercialize due to their low efficiency. Accordingly, the aim of this study was to improve the efficiency of a DSSC via an aluminum film reflective plate, reusing discarded light after it was absorbed. We found that the factor having the most dominant influence on DSSC efficiency was the amount of radiation reacting with the dye. For a reflective plate with θ = 30° and h = 15 mm, DSSC efficiency was increased about three times.

  12. Improving the efficiency of a dye-sensitized solar cell with a reflex condenser system.

    PubMed

    Lee, Sang-min; Lee, Seung-jun; Choi, Soo-chang; Kim, Jong-min; Kim, Jong-man; Kim, Soo-hyung; Lee, Deug-woo

    2012-11-01

    Dye-sensitized solar cells (DSSCs) are inexpensive to manufacture and easy to process in comparison with silicone solar cells, but they are difficult to commercialize due to their low efficiency. Accordingly, the aim of this study was to improve the efficiency of a DSSC via an aluminum film reflective plate, reusing discarded light after it was absorbed. We found that the factor having the most dominant influence on DSSC efficiency was the amount of radiation reacting with the dye. For a reflective plate with [symbol: see text] = 30° and h = 15 mm, DSSC efficiency was increased about three times.

  13. 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.

  14. 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.

  15. Dye-Sensitized Solar Cell with Integrated Triplet-Triplet Annihilation Upconversion System.

    PubMed

    Nattestad, Andrew; Cheng, Yuen Yap; MacQueen, Rowan W; Schulze, Tim F; Thompson, Fletcher W; Mozer, Attila J; Fückel, Burkhard; Khoury, Tony; Crossley, Maxwell J; Lips, Klaus; Wallace, Gordon G; Schmidt, Timothy W

    2013-06-20

    Photon upconversion (UC) by triplet-triplet annihilation (TTA-UC) is employed in order to enhance the response of solar cells to sub-bandgap light. Here, we present the first report of an integrated photovoltaic device, combining a dye-sensitized solar cell (DSC) and TTA-UC system. The integrated device displays enhanced current under sub-bandgap illumination, resulting in a figure of merit (FoM) under low concentration (3 suns), which is competitive with the best values recorded to date for nonintegrated systems. Thus, we demonstrate both the compatibility of DSC and TTA-UC and a viable method for device integration.

  16. 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.

  17. 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

  18. 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.

  19. 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.

  20. 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

  1. Molecular scale characterization of the titania-dye-solvent interface in dye-sensitized solar cells.

    PubMed

    Marquet, Philip; Andersson, Gunther; Snedden, Alan; Kloo, Lars; Atkin, Rob

    2010-06-15

    Charge separation at the dye/titania interface in dye sensitized solar cells is strongly influenced by the thickness and homogeneity of the sensitizing dye layer, as this controls the potential drop across the interface, and the probability of an excited electron being transferred from the dye to the titania. In this study we use atomic force microscopy and the depth profiling method neutral impact collision ion scattering spectroscopy (NICISS) to investigate the thickness and homogeneity of N719 dye adsorbed to titania before and after rinsing with pure acetonitrile. Both experimental methods show that the dye layers are closed but inhomogeneous. Inhomogeneity is more pronounced for unrinsed samples. PMID:20297833

  2. 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.

  3. 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.

  4. 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

  5. Electrospun polyethylene oxide (PEO) nanofiber membranes based polymer electrolyte for dye sensitized solar cell

    NASA Astrophysics Data System (ADS)

    Sethupathy, M.; Sethuraman, V.; Raj, J. Anandha; Muthuraja, P.; Manisankar, P.

    2014-10-01

    Poly (ethyleneoxide) membrane was prepared by electrospinning technique and characterized by HR-SEM, FTIR and XRD analysis. The electrolyte uptake, ionic conductivity and porosity of the membrane were studied. The images revealed that the nanofibers have uniform interconnectivity and no bead formation was observed. The ionic conductivity of gel polymer electrolyte was 1.86 × 10-3 Scm-1 at room temperature. The electrolyte uptake of the membrane reached upto a maximum of ˜94%. The photovoltaic performance of the dye sensitized solar cell using polymer electrolyte was evaluated and reported.

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

    PubMed

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

    2015-09-30

    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.

  7. Hierarchical TiO2 photoanode for dye-sensitized solar cells.

    PubMed

    Sauvage, F; Di Fonzo, F; Li Bassi, A; Casari, C S; Russo, V; Divitini, G; Ducati, C; Bottani, C E; Comte, P; Graetzel, M

    2010-07-14

    Hierarchical or one-dimensional architectures are among the most exciting developments in material science these recent years. We present a nanostructured TiO(2) assembly combining these two concepts and resembling a forest composed of individual, high aspect-ratio, treelike nanostructures. We propose to use these structures for the photoanode in dye-sensitized solar cells, and we achieved 4.9% conversion efficiency in combination with C101 dye. We demonstrate this morphology beneficial to hamper the electron recombination and also mass transport control in the mesopores when solvent-free ionic liquid electrolyte is used.

  8. 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.

  9. 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)

  10. 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)

  11. Energy harvesting of dye-sensitized solar cells assisted with Ti-mesh and phosphor materials

    NASA Astrophysics Data System (ADS)

    He, Weizhen; Timur, Atabaev Sh; Kim, Hyung-Kook; Hwang, Yoon-Hwae

    2014-03-01

    We used the Ti-meshes for both the photoanode and counter electrode of the dye-sensitized solar cells (DSSCs) to improve the flexibility and conductivity of electrodes. This mesh type electrode showed good transparency and high bendability when subjected to an external force. The overall efficiency of the best cells was approximately 5.3% under standard air mass 1.5 global (AM 1.5 G) solar condition. We also modified the TiO2 nanoparticle based dye-sensitized solar cells (DSSCs) by depositing a layer of long-persistent phosphor SrAl2O4:Eu2+, Dy3+ on top of the TiO2 nanoparticle layer to prepare working electrodes of DSSCs. SrAl2O4:Eu2+, Dy3+ red-shifted short UV wavelengths into the main absorption range of the dye commonly used in DSSCs. The SrAl2O4:Eu2+, Dy3+ layer also acted as a light-scattering layer to reduce the loss of visible light. An overall 13% improvement in the conversion efficiency of modified DSSCs was achieved due to the presence of the phosphor layer.

  12. 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.

  13. 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.

  14. 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

  15. 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

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. The influence of local electric fields on photoinduced absorption in dye-sensitized solar cells.

    PubMed

    Cappel, Ute B; Feldt, Sandra M; Schöneboom, Jan; Hagfeldt, Anders; Boschloo, Gerrit

    2010-07-01

    The dye-sensitized solar cell (DSC) challenges conventional photovoltaics with its potential for low-cost production and its flexibility in terms of color and design. Transient absorption spectroscopy is widely used to unravel the working mechanism of DSCs. A surprising, unexplained feature observed in these studies is an apparent bleach of the ground-state absorption of the dye, under conditions where the dye is in the ground state. Here, we demonstrate that this feature can be attributed to a change of the local electric field affecting the absorption spectrum of the dye, an effect related to the Stark effect first reported in 1913. We present a method for measuring the effect of an externally applied electric field on the absorption of dye monolayers adsorbed on flat TiO(2) substrates. The measured signal has the shape of the first derivative of the absorption spectra of the dyes and reverses sign along with the reversion of the direction of the change in dipole moment upon excitation relative to the TiO(2) surface. A very similar signal is observed in photoinduced absorption spectra of dye-sensitized TiO(2) electrodes under solar cell conditions, demonstrating that the electric field across the dye molecules changes upon illumination. This result has important implications for the analysis of transient absorption spectra of DSCs and other molecular optoelectronic devices and challenges the interpretation of many previously published results.

  1. 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.

  2. 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).

  3. 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.

  4. 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

  5. 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.

  6. Interfacial modification to optimize stainless steel photoanode design for flexible dye sensitized solar cells: an experimental and numerical modeling approach

    NASA Astrophysics Data System (ADS)

    Salehi Taleghani, Sara; Zamani Meymian, Mohammad Reza; Ameri, Mohsen

    2016-10-01

    In the present research, we report fabrication, experimental characterization and theoretical analysis of semi and full flexible dye sensitized solar cells (DSSCs) manufactured on the basis of bare and roughened stainless steel type 304 (SS304) substrates. The morphological, optical and electrical characterizations confirm the advantage of roughened SS304 over bare and even common transparent conducting oxides (TCOs). A significant enhancement of about 51% in power conversion efficiency is obtained for flexible device (5.51%) based on roughened SS304 substrate compared to the bare SS304. The effect of roughening the SS304 substrates on electrical transport characteristics is also investigated by means of numerical modeling with regard to metal-semiconductor and interfacial resistance arising from the metallic substrate and nanocrystalline semiconductor contact. The numerical modeling results provide a reliable theoretical backbone to be combined with experimental implications. It highlights the stronger effect of series resistance compared to schottky barrier in lowering the fill factor of the SS304-based DSSCs. The findings of the present study nominate roughened SS304 as a promising replacement for conventional DSSCs substrates as well as introducing a highly accurate modeling framework to design and diagnose treated metallic or non-metallic based DSSCs.

  7. Effect of compressed TiO2 nanoparticle thin film thickness on the performance of dye-sensitized solar cells

    PubMed Central

    2013-01-01

    In this study, dye-sensitized solar cells (DSSCs) were fabricated using nanocrystalline titanium dioxide (TiO2) nanoparticles as photoanode. Photoanode thin films were prepared by doctor blading method with 420 kg/cm2 of mechanical compression process and heat treatment in the air at 500°C for 30 min. The optimal thickness of the TiO2 NP photoanode is 26.6 μm with an efficiency of 9.01% under AM 1.5G illumination at 100 mW/cm2. The efficiency is around two times higher than that of conventional DSSCs with an uncompressed photoanode. The open-circuit voltage of DSSCs decreases as the thickness increases. One DSSC (sample D) has the highest conversion efficiency while it has the maximum short-circuit current density. The results indicate that the short-circuit current density is a compromise between two conflict factors: enlargement of the surface area by increasing photoanode thickness and extension of the electron diffusion length to the electrode as the thickness increases. PMID:24192482

  8. Preparation of TiO₂ nanowires/nanotubes using polycarbonate membranes and their uses in dye-sensitized solar cells.

    PubMed

    Roh, Dong Kyu; Patel, Rajkumar; Ahn, Sung Hoon; Kim, Dong Jun; Kim, Jong Hak

    2011-10-01

    Track-etched polycarbonate (PC) membranes were used as a soft template to synthesize mesoporous TiO(2) for use in dye-sensitized solar cells (DSSCs). The Ti precursor infiltrated into the cylindrical confined spaces of PC membranes. Upon calcination at 500 °C, TiO(2) nanowires (15TNW) were obtained from PC with a 15 nm pore diameter, whereas TiO(2) nanotubes (50TNT and 100TNT) were generated from PC with 50 and 100 nm diameter pores, respectively. TNW and TNT were used as photoelectrodes in DSSCs employing a polymer electrolyte. The ranking of the cell efficiencies of the 200 nm thick TiO(2) films was 50TNT (1.1%) > 15TNW (0.8%) ≅ 100TNT (0.7%), which was mostly attributed to different amounts of dye adsorption due to different surface areas. These TNW and TNT films were further coated with the graft copolymer-directed mesoporous TiO(2) and were used as interfacial layers between the FTO glass and the 4 μm thick nanocrystalline TiO(2) film. As a result, the order of energy conversion efficiency was 15TNW (5.0%) ≅ 50TNT (4.8%) > 100TNT (4.1%). The improved performance of 15TNW was due to a higher transmittance through the electrode and a longer electron lifetime for recombination. The DSSC performance was systematically investigated in terms of interfacial resistance and charge recombination using electrochemical impedance spectroscopy.

  9. 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.

  10. An organic redox electrolyte to rival triiodide/iodide in dye-sensitized solar cells.

    PubMed

    Wang, Mingkui; Chamberland, Nathalie; Breau, Livain; Moser, Jacques-E; Humphry-Baker, Robin; Marsan, Benoît; Zakeeruddin, Shaik M; Grätzel, Michael

    2010-05-01

    Dye-sensitized solar cells (DSCs) have achieved impressive conversion efficiencies for solar energy of over 11% with an electrolyte that contains triiodide/iodide as a redox couple. Although triiodide/iodide redox couples work efficiently in DSCs, they suffer from two major disadvantages: electrolytes that contain triiodide/iodide corrode electrical contacts made of silver (which reduces the options for the scale up of DSCs to module size) and triiodide partially absorbs visible light. Here, we present a new disulfide/thiolate redox couple that has negligible absorption in the visible spectral range, a very attractive feature for flexible DSCs that use transparent conductors as current collectors. Using this novel, iodide-free redox electrolyte in conjunction with a sensitized heterojunction, we achieved an unprecedented efficiency of 6.4% under standard illumination test conditions. This novel redox couple offers a viable pathway to develop efficient DSCs with attractive properties for scale up and practical applications.

  11. 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.

  12. 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.

  13. 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%.

  14. 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.

  15. Rational screening low-cost counter electrodes for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Hou, Yu; Wang, Dong; Yang, Xiao Hua; Fang, Wen Qi; Zhang, Bo; Wang, Hai Feng; Lu, Guan Zhong; Hu, P.; Zhao, Hui Jun; Yang, Hua Gui

    2013-03-01

    Dye-sensitized solar cells have attracted intense research attention owing to their ease of fabrication, cost-effectiveness and high efficiency in converting solar energy. Noble platinum is generally used as catalytic counter electrode for redox mediators in electrolyte solution. Unfortunately, platinum is expensive and non-sustainable for long-term applications. Therefore, researchers are facing with the challenge of developing low-cost and earth-abundant alternatives. So far, rational screening of non-platinum counter electrodes has been hamstrung by the lack of understanding about the electrocatalytic process of redox mediators on various counter electrodes. Here, using first-principle quantum chemical calculations, we studied the electrocatalytic process of redox mediators and predicted electrocatalytic activity of potential semiconductor counter electrodes. On the basis of theoretical predictions, we successfully used rust (α-Fe2O3) as a new counter electrode catalyst, which demonstrates promising electrocatalytic activity towards triiodide reduction at a rate comparable to platinum.

  16. 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.

  17. Advantages of using Ti-mesh type electrodes for flexible dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    He, Weizhen; Qiu, Jijun; Zhuge, Fuwei; Li, Xiaomin; Lee, Jae-Ho; Kim, Yang-Do; Kim, Hyung-Kook; Hwang, Yoon-Hwae

    2012-06-01

    We used Ti meshes for both the photoanodes and counter electrodes of dye-sensitized solar cells (DSSCs) to improve the flexibility and conductivity of the electrodes. These mesh type electrodes showed good transparency and high bendability when subjected to an external force. We demonstrated the advantages of cells using such electrodes compared to traditional transparent conducting oxide based electrodes and back side illuminated DSSCs, such as low sheet resistance, elevated photo-induced current and enhanced sunlight utilization. Nanotube layers of different thicknesses were investigated to determine their effect on the photovoltaic parameters of the cell. The overall efficiency of the best cells was approximately 5.3% under standard air mass 1.5 global (AM 1.5 G) solar conditions. Furthermore, the DSSCs showed an efficiency of approximately 3.15% due to the all Ti-mesh type electrodes even after illumination from the back side.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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

  3. 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.

  4. 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].

  5. 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

  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

    2016-07-22

    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.

  7. 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.

  8. 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

  9. Analysis of Chameleonic Change of Red Cabbage Depending on Broad pH Range for Dye-Sensitized Solar Cells.

    PubMed

    Park, Kyung Hee; Kim, Tae Young; Ko, Hyun Seok; Han, Eun Mi; Lee, Suk-Ho; Kim, Jung-Hun; Lee, Jae Wook

    2015-08-01

    Dye-sensitized solar cells (DSSCs) were assembled using natural dyes extracted from red cabbage as a sensitizer. In this work, we investigated the adsorption characteristics and the electrochemical behavior for harvesting sunlight and electron transfer in red cabbage DSSCs under different solvents and pH. For the red cabbage dye-sensitized electrode adsorbed at pH 3.5, the solar cell yields a short-circuit current density (Jsc) of 1.60 mA/cm2, a photovoltage (Vcc) of 0.46 V, and a fill factor of 0.55, corresponding to an energy conversion efficiency (η) of 0.41%.

  10. 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%.

  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. Kinetic and energetic paradigms for dye-sensitized solar cells: moving from the ideal to the real.

    PubMed

    O'Regan, Brian C; Durrant, James R

    2009-11-17

    Dye-sensitized solar cells (DSSCs) are photoelectrochemical solar cells. Their function is based on photoinduced charge separation at a dye-sensitized interface between a nanocrystalline, mesoporous metal oxide electrode and a redox electrolyte. They have been the subject of substantial academic and commercial research over the last 20 years, motivated by their potential as a low-cost solar energy conversion technology. Substantial progress has been made in enhancing the efficiency, stability, and processability of this technology and, in particular, the interplay between these technology drivers. However, despite intense research efforts, our ability to identify predictive materials and structure/device function relationships and, thus, achieve the rational optimization of materials and device design, remains relatively limited. A key challenge in developing such predictive design tools is the chemical complexity of the device. DSSCs comprise distinct materials components, including metal oxide nanoparticles, a molecular sensitizer dye, and a redox electrolyte, all of which exhibit complex interactions with each other. In particular, the electrolyte alone is chemically complex, including not only a redox couple (almost always iodide/iodine) but also a range of additional additives found empirically to enhance device performance. These molecular solutes make up typically 20% of the electrolyte by volume. As with most molecular systems, they exhibit complex interactions with both themselves and the other device components (e.g., the sensitizer dye and the metal oxide). Moreover, these interactions can be modulated by solar irradiation and device operation. As such, understanding the function of these photoelectrochemical solar cells requires careful consideration of the chemical complexity and its impact upon device operation. In this Account, we focus on the process by which electrons injected into the nanocrystalline electrode are collected by the external

  13. 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.

  14. Comparison of different structures of niobium oxide blocking layer for dye-sensitized solar cells.

    PubMed

    Chun, Jae Hwan; Kim, Jong Sung

    2014-08-01

    In this study, four different types of Nb2O5 thin layers were prepared using sol-gel process to improve energy conversion efficiency of dye sensitized solar cells (DSSCs). Nb2O5 layer was prepared on the fluorine-doped tin oxide (FTO) layer, TiO2 electrode layer, and inside of TiO2 layer, respectively. The Nb2O5 layer was used to reduce the recombination of photo induced electrons and holes. The DSSCs were assembled with platinum (Pt) coated counter electrode, ruthenium dye, and iodine based electrolyte. The photocurrent-voltage (I-V) characteristics of DSSCs with different types of Nb2O5 were studied. The efficiency depends not only on the structure of DSSCs but also on the initial compositions for the preparation of Nb2O5.

  15. 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

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

    PubMed

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

    2016-07-21

    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.

  17. 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

  18. The Dye Sensitized Photoelectrosynthesis Cell (DSPEC) for Solar Water Splitting and CO2 Reduction

    NASA Astrophysics Data System (ADS)

    Meyer, Thomas; Alibabaei, Leila; Sherman, Benjamin; Sheridan, Matthew; Ashford, Dennis; Lapides, Alex; Brennaman, Kyle; Nayak, Animesh; Roy, Subhangi; Wee, Kyung-Ryang; Gish, Melissa; Meyer, Jerry; Papanikolas, John

    The dye-sensitized photoelectrosynthesis cell (DSPEC) integrates molecular level light absorption and catalysis with the bandgap properties of stable oxide materials such as TiO2 and NiO. Excitation of surface-bound chromophores leads to excited state formation and rapid electron or hole injection into the conduction or valence bands of n or p-type oxides. Addition of thin layers of TiO2 or NiO on the surfaces of mesoscopic, nanoparticle films of semiconductor or transparent conducting oxides to give core/shell structures provides a basis for accumulating multiple redox equivalents at catalysts for water oxidation or CO2 reduction. UNC EFRC Center for Solar Fuels, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Award Number DE-SC0001011.

  19. 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.

  20. 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.

  1. Low-cost carbon-based counter electrodes for dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Barberio, M.; Imbrogno, A.; Grosso, D. R.; Bonanno, A.; Xu, F.

    2015-07-01

    In this work, we present the realization of four carbon-based counter electrodes for dye-sensitized solar cells. The photovoltaic behaviours of counter electrodes realized with graphene, multiwalled carbon nanotubes, and nanocomposites of multiwalled carbon nanotubes and metal nanoparticles are compared with those of classical electrodes (amorphous carbon and platinum). Our results show an increase of about 50% in PCE for graphene and Ag/carbon nanotube electrodes with respect to amorphous carbon and of 25% in comparison to platinum. An improvement in cell stability is also observed; in fact, the PCE of all carbon-based cells assumes a constant value during a period of one month while that with the Pt electrode decreases by 50% in one week.

  2. 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.

  3. 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.

  4. Metal-organic frameworks at interfaces in dye-sensitized solar cells.

    PubMed

    Li, Yafeng; Chen, Caiyun; Sun, Xun; Dou, Jie; Wei, Mingdeng

    2014-09-01

    ZIF-8, a kind of widely studied metal-organic frameworks, was used for the interfacial modification of dye-sensitized solar cells by a facile post-treatment strategy for the first time, which solved the problem of severely decreased short-circuit photocurrent in previous report. After the surface treatment, the performance of cells was obviously improved. The conditions for the deposition of ZIF-8 were optimized. The best photovoltaic property was obtained when the growth time of ZIF-8 was 7 min and the TiO2 photoanode was post-treated for 2 times. Besides the energy barrier effect of ZIF-8 that improved the open-circuit photovoltage and electron lifetime, the dyes adsorbed tightly on TiO2 surface was found to be a key point for the efficient electron injection and improved performance.

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

    NASA Astrophysics Data System (ADS)

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

    2016-07-01

    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.

  6. Molecular design and photovoltaic performance of organic dyes containing phenothiazine for dye-sensitized solar cells.

    PubMed

    Jo, Hyo Jeong; Nam, Jung Eun; Sim, Kyoseung; Kim, Dae-Hwan; Kim, Jae Hong; Kang, Jin-Kyu

    2014-10-01

    We synthesized novel organic photosensitizers based on fluorine-substituted phenothiazine with thiophene bridge units in the chromophore for application in dye-sensitized solar cells (DSSCs). Furthermore, organic dyes with different acceptors exhibited higher molar extinction coefficients, and better light absorption at longer wavelengths. The photovoltaic properties of organic dyes composed of different acceptors in their chromophores were measured to identify their effects on the DSSC performance. The organic dye, PFSCN2 containing multi-cyanoacrylic acid as the electron acceptor, showed a power conversion efficiency of 4.67% under AM 1.5 illumination (100 mW/cm2). The retarded recombination kinetics from TiO2 electrode to electrolyte enhanced the electron life time of the organic dye, PFSCN2 in the photoanode of the DSSC. This was confirmed with impedance analysis.

  7. New synthetic routes towards soluble and dissymmetric triphenodioxazine dyes designed for dye-sensitized solar cells.

    PubMed

    Nicolas, Yohann; Allama, Fouzia; Lepeltier, Marc; Massin, Julien; Castet, Frédéric; Ducasse, Laurent; Hirsch, Lionel; Boubegtiten, Zahia; Jonusauskas, Gediminas; Olivier, Céline; Toupance, Thierry

    2014-03-24

    New π-conjugated structures are constantly the subject of research in dyes and pigments industry and electronic organic field. In this context, the triphenodioxazine (TPDO) core has often been used as efficient photostable pigments and once integrated in air stable n-type organic field-effect transistor (OFET). However, little attention has been paid to the TPDO core as soluble materials for optoelectronic devices, possibly due to the harsh synthetic conditions and the insolubility of many compounds. To benefit from the photostability of TPDO in dye-sensitized solar cells (DSCs), an original synthetic pathway has been established to provide soluble and dissymmetric molecules applied to a suitable design for the sensitizers of DSC. The study has been pursued by the theoretical modeling of opto-electronic properties, the optical and electronic characterizations of dyes and elaboration of efficient devices. The discovery of new synthetic pathways opens the way to innovative designs of TPDO for materials used in organic electronics.

  8. Tropolone as a High-Performance Robust Anchoring Group for Dye-Sensitized Solar Cells.

    PubMed

    Higashino, Tomohiro; Fujimori, Yamato; Sugiura, Kenichi; Tsuji, Yukihiro; Ito, Seigo; Imahori, Hiroshi

    2015-07-27

    A tropolone group has been employed for the first time as an anchoring group for dye-sensitized solar cells (DSSCs). The DSSC based on a porphyrin, YD2-o-C8T, with a tropolone moiety exhibited a power-conversion efficiency of 7.7 %, which is only slightly lower than that observed for a reference porphyrin, YD2-o-C8, with a conventional carboxylic group. More importantly, YD2-o-C8T was found to be superior to YD2-o-C8 with respect to DSSC durability and binding ability to TiO2 . These results unambiguously demonstrate that tropolone is a highly promising dye-anchoring group for DSSCs in terms of device durability as well as photovoltaic performance.

  9. 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

  10. 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

  11. 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.

  12. 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.

  13. 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.

  14. Flexible, Low Cost, and Platinum-Free Counter Electrode for Efficient Dye-Sensitized Solar Cells.

    PubMed

    Ali, Abid; Shehzad, Khurram; Ur-Rahman, Faiz; Shah, Syed Mujtaba; Khurram, Muhammad; Mumtaz, Muhammad; Sagar, Rizwan Ur Rehman

    2016-09-28

    A platinum-free counter electrode composed of surface modified aligned multiwalled carbon nanotubes (MWCNTs) fibers was fabricated for efficient flexible dye-sensitized solar cells (DSSCs). Surface modification of MWCNTs fibers with simple one step hydrothermal deposition of cobalt selenide nanoparticles, confirmed by scanning electron microscopy and X-ray diffraction, provided a significant improvement (∼2-times) in their electrocatalytic activity. Cyclic voltammetry and electrochemical impedance spectroscopy suggest a photoelectric conversion efficiency of 6.42% for our modified fibers, higher than 3.4% and 5.6% efficeincy of pristine MWCNTs fiber and commonly used Pt wire, respectively. Good mechanical and performance stability after repeated bending and high output voltage for in-series connection suggest that our surface modified MWCNTs fiber based DSSCs may find applications as flexible power source in next-generation flexible/wearable electronics.

  15. 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)).

  16. 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

  17. 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.

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

    PubMed

    Zhang, Xi; Huang, Xuezhen; Jiang, Hongrui

    2013-05-14

    We discovered a method of applying a forward pulsed bias to recover the degraded 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

  19. 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.

  20. Blue-Coloured Highly Efficient Dye-Sensitized Solar Cells by Implementing the Diketopyrrolopyrrole Chromophore

    NASA Astrophysics Data System (ADS)

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

    2013-08-01

    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.

  1. 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.

  2. Characterization of Nephelium Lappaceum Peel Extract as a Dye Sensitized Solar Cell

    NASA Astrophysics Data System (ADS)

    Budi Poernomo, Joko; Hidayati Mukaromah, Ana; Widiyandari, Hendri; Marwoto, Putut

    2016-08-01

    The world now is searching for a new renewable alternative energy. Nephelium lappaceum is a popular fruit in Indonesia that contains anthocyanin. Anthocyanin can absorb light on the range of visible light due to its conjugated double bonds. This finding makes Nephelium lappaceum as a potential Dye Sensitized Solar Cell (DSSC). The Nephelium lappaceum extract can be taken through extraction technique, called maserasi. The process of developing DSSC material was initiated by preparing TiO2 photoanode using a conventional sintering procedure. It was, then, followed by doping TiO2 on the Fluoride doped tin oxcide (FTO) with resistance value of 10-20 ohm/q. Finally, the electrode counter made of platinum paste was developed by implementing conventional sintering procedure. All of the above process were then continued by the DSSC assembly. In this process, the TiO2 photoanode which has passed the absorption process for 24 hours, was doped on the counter electrode. After doping, the process was stopped by doing electrolyte solution filling into prepared electrode counter holes. In order to characterize the DSSC, a solar simulator connected to a computer was employed. Based on this characterization process, it was found that the maximum value of Voc was 0.29 V, the maximum value of current density was 0.56 mA / cm2, the maximum power was 0.062 mW / cm2 and efficiency of 0.063. Characteristics of Nephelium lappaceum peel extract is one of the DSSC cells using TiO2 as a semiconductor material as a dye sensitizer that can convert light energy into electrical energy.

  3. Efficient p-type dye-sensitized solar cells based on disulfide/thiolate electrolytes

    NASA Astrophysics Data System (ADS)

    Xu, Xiaobao; Zhang, Bingyan; Cui, Jin; Xiong, Dehua; Shen, Yan; Chen, Wei; Sun, Licheng; Cheng, Yibing; Wang, Mingkui

    2013-08-01

    Herein, an organic redox couple 1-methy-1H-tetrazole-5-thiolate (T-) and its disulfide dimer (T2) redox shuttle, as an electrolyte, is introduced in a p-type dye-sensitized solar cell (DSC) on the basis of an organic dye (P1) sensitizer and nanocrystal CuCrO2 electrode. Using this iodide-free transparent redox electrolyte in conjunction with the sensitized heterojunction, we achieve a high open-circuit voltage of over 300 mV. An optimal efficiency of 0.23% is obtained using a CoS counter electrode and an optimized electrolyte composition under AM 1.5 G 100 mW cm-2 light illumination which, to the best of our knowledge, represents the highest efficiency that has so far been reported for p-type DSCs using organic redox couples.Herein, an organic redox couple 1-methy-1H-tetrazole-5-thiolate (T-) and its disulfide dimer (T2) redox shuttle, as an electrolyte, is introduced in a p-type dye-sensitized solar cell (DSC) on the basis of an organic dye (P1) sensitizer and nanocrystal CuCrO2 electrode. Using this iodide-free transparent redox electrolyte in conjunction with the sensitized heterojunction, we achieve a high open-circuit voltage of over 300 mV. An optimal efficiency of 0.23% is obtained using a CoS counter electrode and an optimized electrolyte composition under AM 1.5 G 100 mW cm-2 light illumination which, to the best of our knowledge, represents the highest efficiency that has so far been reported for p-type DSCs using organic redox couples. Electronic supplementary information (ESI) available: Optimization of electrolyte concentration and the solvent used in the experiment, and the effects of different redox couples and the counter electrode on the dark current. See DOI: 10.1039/c3nr02169f

  4. Insertion of Dye-Sensitized Solar Cells in Textiles using a Conventional Weaving Process

    PubMed Central

    Yun, Min Ju; Cha, Seung I.; Seo, Seon Hee; kim, Han Seong; Lee, Dong Y.

    2015-01-01

    Increasing demands for wearable energy sources and highly flexible, lightweight photovoltaic devices have stimulated the development of textile-structured solar cells. However, the former approach of wire-type solar cell fabrication, followed by weaving of these devices, has had limited success, due to device failure caused by high friction forces and tension forces during the weaving process. To overcome this limitation, we present a new approach for textile solar cell fabrication, in which dye-sensitized solar cell (DSSC) electrodes are incorporated into the textile during the weaving process, using the textile warp as a spacer to maintain the DSSC structure. Porous, dye-loaded TiO2-coated holed metal ribbon and Pt nanoparticle-loaded carbon yarn were used as the photoanode and counterelectrode, respectively. The highly flexible textile-based solar cell was fabricated using a common weaving process with a loom. The inserted DSSCs in the textile demonstrated an energy conversion efficiency of 2.63% (at 1 sun, 1.5 A.M.). Our results revealed that additional performance enhancement was possible by considering other electrode materials and textile structures, as well as where and how the DSSC electrodes are inserted. In addition, we demonstrated that the inserted DSSCs could be electrically connected using a parallel configuration. PMID:26087134

  5. Insertion of Dye-Sensitized Solar Cells in Textiles using a Conventional Weaving Process.

    PubMed

    Yun, Min Ju; Cha, Seung I; Seo, Seon Hee; Kim, Han Seong; Lee, Dong Y

    2015-01-01

    Increasing demands for wearable energy sources and highly flexible, lightweight photovoltaic devices have stimulated the development of textile-structured solar cells. However, the former approach of wire-type solar cell fabrication, followed by weaving of these devices, has had limited success, due to device failure caused by high friction forces and tension forces during the weaving process. To overcome this limitation, we present a new approach for textile solar cell fabrication, in which dye-sensitized solar cell (DSSC) electrodes are incorporated into the textile during the weaving process, using the textile warp as a spacer to maintain the DSSC structure. Porous, dye-loaded TiO2-coated holed metal ribbon and Pt nanoparticle-loaded carbon yarn were used as the photoanode and counterelectrode, respectively. The highly flexible textile-based solar cell was fabricated using a common weaving process with a loom. The inserted DSSCs in the textile demonstrated an energy conversion efficiency of 2.63% (at 1 sun, 1.5 A.M.). Our results revealed that additional performance enhancement was possible by considering other electrode materials and textile structures, as well as where and how the DSSC electrodes are inserted. In addition, we demonstrated that the inserted DSSCs could be electrically connected using a parallel configuration.

  6. Insertion of Dye-Sensitized Solar Cells in Textiles using a Conventional Weaving Process.

    PubMed

    Yun, Min Ju; Cha, Seung I; Seo, Seon Hee; Kim, Han Seong; Lee, Dong Y

    2015-01-01

    Increasing demands for wearable energy sources and highly flexible, lightweight photovoltaic devices have stimulated the development of textile-structured solar cells. However, the former approach of wire-type solar cell fabrication, followed by weaving of these devices, has had limited success, due to device failure caused by high friction forces and tension forces during the weaving process. To overcome this limitation, we present a new approach for textile solar cell fabrication, in which dye-sensitized solar cell (DSSC) electrodes are incorporated into the textile during the weaving process, using the textile warp as a spacer to maintain the DSSC structure. Porous, dye-loaded TiO2-coated holed metal ribbon and Pt nanoparticle-loaded carbon yarn were used as the photoanode and counterelectrode, respectively. The highly flexible textile-based solar cell was fabricated using a common weaving process with a loom. The inserted DSSCs in the textile demonstrated an energy conversion efficiency of 2.63% (at 1 sun, 1.5 A.M.). Our results revealed that additional performance enhancement was possible by considering other electrode materials and textile structures, as well as where and how the DSSC electrodes are inserted. In addition, we demonstrated that the inserted DSSCs could be electrically connected using a parallel configuration. PMID:26087134

  7. Ultrafast and slow charge recombination dynamics of diketopyrrolopyrrole-NiO dye sensitized solar cells.

    PubMed

    Zhang, Lei; Favereau, Ludovic; Farré, Yoann; Mijangos, Edgar; Pellegrin, Yann; Blart, Errol; Odobel, Fabrice; Hammarström, Leif

    2016-07-21

    In a photophysical study, two diketopyrrolopyrrole (DPP)-based sensitizers functionalized with 4-thiophenecarboxylic acid as an anchoring group and a bromo (DPPBr) or dicyanovinyl (DPPCN2) group, and a dyad consisting of a DPP unit linked to a naphthalenediimide group (DPP-NDI), were investigated both in solution and grafted on mesoporous NiO films. Femtosecond transient absorption measurements indicate that ultrafast hole injection occurred predominantly on a timescale of ∼200 fs, whereas the subsequent charge recombination occurred on a surprisingly wide range of timescales, from tens of ps to tens of μs; this kinetic heterogeneity is much greater than is typically observed for dye-sensitized TiO2 or ZnO. Also, in contrast to what is typically observed for dye-sensitized TiO2, there was no significant dependence on the excitation power of the recombination kinetics, which can be explained by the hole density being comparatively higher near the valence band of NiO before excitation. The additional acceptor group in DPP-NDI provided a rapid electron shift and stabilized charge separation up to the μs timescale. This enabled efficient (∼95%) regeneration of NDI by a Co(III)(dtb)3 electrolyte (dtb = 4,4'-di-tert-butyl-2,2'-bipyridine), according to transient absorption measurements. The regeneration of DPPBr and DPPCN2 by Co(III)(dtb)3 was instead inefficient, as most recombination for these dyes occurred on the sub-ns timescale. The transient spectroscopy data thus corroborated the trend of the published photovoltaic properties of dye-sensitized solar cells (DSSCs) based on these dyes on mesoporous NiO, and show the potential of a design strategy with a secondary acceptor bound to the dye. The study identifies rapid initial recombination between the dye and NiO as the main obstacle to obtaining high efficiencies in NiO-based DSSCs; these recombination components may be overlooked when studies are conducted using only methods with ns resolution or slower. PMID

  8. Pigments from UV-resistant Antarctic bacteria as photosensitizers in Dye Sensitized Solar Cells.

    PubMed

    Órdenes-Aenishanslins, N; Anziani-Ostuni, G; Vargas-Reyes, M; Alarcón, J; Tello, A; Pérez-Donoso, J M

    2016-09-01

    Here we report the use of pigments produced by UV-resistant Antarctic bacteria as photosensitizers in Dye Sensitized Solar Cells (DSSCs). Pigments were obtained from red and yellow colored psychrotolerant bacteria isolated from soils of King George Island, Antarctica. Based on metabolic characteristics and 16s DNA sequence, pigmented bacteria were identified as Hymenobacter sp. (red) and Chryseobacterium sp. (yellow). Pigments produced by these microorganisms were extracted and classified as carotenoids based on their spectroscopic and structural characteristics, determined by UV-Vis spectrophotometry and infrared spectroscopy (FTIR), respectively. With the purpose of develop green solar cells based on bacterial pigments, the photostability and capacity of these molecules as light harvesters in DSSCs were determined. Absorbance decay assays determined that bacterial carotenoids present high photostability. In addition, solar cells based on these photosensitizers exhibit an open circuit voltage (VOC) of 435.0 [mV] and a short circuit current density (ISC) of 0.2 [mA·cm(-2)] for the red pigment, and a VOC of 548.8 [mV] and a ISC of 0.13 [mA·cm(-2)] for the yellow pigment. This work constitutes the first approximation of the use of pigments produced by non-photosynthetic bacteria as photosensitizers in DSSCs. Determined photochemical characteristics of bacterial pigments, summed to their easy obtention and low costs, validates its application as photosensitizers in next-generation biological solar cells.

  9. Indoor Light Performance of Coil Type Cylindrical Dye Sensitized Solar Cells.

    PubMed

    Kapil, Gaurav; Ogomi, Yuhei; Pandey, Shyam S; Ma, Tingli; Hayase, Shuzi

    2016-04-01

    A very good performance under low/diffused light intensities is one of the application areas in which dye-sensitized solar cells (DSSCs) can be utilized effectively compared to their inorganic silicon solar cell counterparts. In this article, we have investigated the 1 SUN and low intensity fluorescent light performance of Titanium (Ti)-coil based cylindrical DSSC (C-DSSC) using ruthenium based N719 dye and organic dyes such as D205 and Y123. Electrochemical impedance spectroscopic results were analyzed for variable solar cell performances. Reflecting mirror with parabolic geometry as concentrator was also utilized to tap diffused light for indoor applications. Fluorescent light at relatively lower illumination intensities (0.2 mW/cm2 to 0.5 mW/cm2) were used for the investigation of TCO-less C-DSSC performance with and without reflector geometry. Furthermore, the DSSC performances were analyzed and compared with the commercially available amorphous silicon based solar cell for indoor applications. PMID:27451601

  10. Stabilized Conversion Efficiency and Dye-Sensitized Solar Cells from Beta vulgaris Pigment

    PubMed Central

    Hernández-Martínez, Angel Ramon; Estévez, Miriam; Vargas, Susana; Rodríguez, Rogelio

    2013-01-01

    Dye-Sensitized Solar Cells (DSSCs), based on TiO2 and assembled using a dye from Beta vulgaris extract (BVE) with Tetraethylorthosilicate (TEOS), are reported. The dye BVE/TEOS increased its UV resistance, rendering an increase in the cell lifetime; the performance of these solar cells was compared to those prepared with BVE without TEOS. The efficiency η for the solar energy conversion was, for BVE and BVE/TEOS, of 0.89% ± 0.006% and 0.68% ± 0.006% with a current density Jsc of 2.71 ± 0.003 mA/cm2 and 2.08 ± 0.003 mA/cm2, respectively, using in both cases an irradiation of 100 mW/cm2 at 25 °C. The efficiency of the BVE solar cell dropped from 0.9 ± 0.006 to 0.85 ± 0.006 after 72 h of operation, whereas for the BVE/TEOS, the efficiency remained practically constant in the same period of time. PMID:23429194

  11. Pigments from UV-resistant Antarctic bacteria as photosensitizers in Dye Sensitized Solar Cells.

    PubMed

    Órdenes-Aenishanslins, N; Anziani-Ostuni, G; Vargas-Reyes, M; Alarcón, J; Tello, A; Pérez-Donoso, J M

    2016-09-01

    Here we report the use of pigments produced by UV-resistant Antarctic bacteria as photosensitizers in Dye Sensitized Solar Cells (DSSCs). Pigments were obtained from red and yellow colored psychrotolerant bacteria isolated from soils of King George Island, Antarctica. Based on metabolic characteristics and 16s DNA sequence, pigmented bacteria were identified as Hymenobacter sp. (red) and Chryseobacterium sp. (yellow). Pigments produced by these microorganisms were extracted and classified as carotenoids based on their spectroscopic and structural characteristics, determined by UV-Vis spectrophotometry and infrared spectroscopy (FTIR), respectively. With the purpose of develop green solar cells based on bacterial pigments, the photostability and capacity of these molecules as light harvesters in DSSCs were determined. Absorbance decay assays determined that bacterial carotenoids present high photostability. In addition, solar cells based on these photosensitizers exhibit an open circuit voltage (VOC) of 435.0 [mV] and a short circuit current density (ISC) of 0.2 [mA·cm(-2)] for the red pigment, and a VOC of 548.8 [mV] and a ISC of 0.13 [mA·cm(-2)] for the yellow pigment. This work constitutes the first approximation of the use of pigments produced by non-photosynthetic bacteria as photosensitizers in DSSCs. Determined photochemical characteristics of bacterial pigments, summed to their easy obtention and low costs, validates its application as photosensitizers in next-generation biological solar cells. PMID:27508881

  12. Novel near-infrared carboxylated 1,3-indandione sensitizers for highly efficient flexible dye-sensitized solar cells.

    PubMed

    Shibayama, Naoyuki; Inoue, Yukiko; Abe, Masahiro; Kajiyama, Shingo; Ozawa, Hironobu; Miura, Hidetoshi; Arakawa, Hironori

    2015-08-18

    Three novel metal-free organic dyes (DN458, DN475 and DN484) were designed for use in plastic-substrate dye-sensitized solar cells (PDSCs). The photoelectric conversion region of DN475 was successfully expanded into the near-infrared region. As a result, an energy conversion efficiency of 5.76% was achieved.

  13. In situ growth of a MoSe2/Mo counter electrode for high efficiency dye-sensitized solar cells.

    PubMed

    Chen, Haijie; Xie, Yian; Cui, Houlei; Zhao, Wei; Zhu, Xiaolong; Wang, Yaoming; Lü, Xujie; Huang, Fuqiang

    2014-05-01

    A facile and economical MoSe2/Mo structure was in situ prepared to replace the currently preferred expensive Pt and FTO counter electrode (CE) in dye-sensitized solar cells. A power conversion efficiency of 8.13% was achieved, which is comparable to that with Pt-sputtered FTO electrode (8.06%).

  14. Novel near-infrared carboxylated 1,3-indandione sensitizers for highly efficient flexible dye-sensitized solar cells.

    PubMed

    Shibayama, Naoyuki; Inoue, Yukiko; Abe, Masahiro; Kajiyama, Shingo; Ozawa, Hironobu; Miura, Hidetoshi; Arakawa, Hironori

    2015-08-18

    Three novel metal-free organic dyes (DN458, DN475 and DN484) were designed for use in plastic-substrate dye-sensitized solar cells (PDSCs). The photoelectric conversion region of DN475 was successfully expanded into the near-infrared region. As a result, an energy conversion efficiency of 5.76% was achieved. PMID:26166712

  15. Cyanomethylbenzoic acid: an acceptor for donor-π-acceptor chromophores used in dye-sensitized solar cells.

    PubMed

    Xiang, Wanchun; Gupta, Akhil; Kashif, Muhammad Kalim; Duffy, Noel; Bilic, Ante; Evans, Richard A; Spiccia, Leone; Bach, Udo

    2013-02-01

    Sensing the sun: Incorporation of a cyanomethyl benzoic acid electron acceptor into donor-π-acceptor sensitizers for dye-sensitized-solar cell is shown to lead to devices with improved conversion efficiency when compared with more widely used cyanoacetic acid acceptor.

  16. On global energy scenario, dye-sensitized solar cells and the promise of nanotechnology.

    PubMed

    Reddy, K Govardhan; Deepak, T G; Anjusree, G S; Thomas, Sara; Vadukumpully, Sajini; Subramanian, K R V; Nair, Shantikumar V; Nair, A Sreekumaran

    2014-04-21

    One of the major problems that humanity has to face in the next 50 years is the energy crisis. The rising population, rapidly changing life styles of people, heavy industrialization and changing landscape of cities have increased energy demands, enormously. The present annual worldwide electricity consumption is 12 TW and is expected to become 24 TW by 2050, leaving a challenging deficit of 12 TW. The present energy scenario of using fossil fuels to meet the energy demand is unable to meet the increase in demand effectively, as these fossil fuel resources are non-renewable and limited. Also, they cause significant environmental hazards, like global warming and the associated climatic issues. Hence, there is an urgent necessity to adopt renewable sources of energy, which are eco-friendly and not extinguishable. Of the various renewable sources available, such as wind, tidal, geothermal, biomass, solar, etc., solar serves as the most dependable option. Solar energy is freely and abundantly available. Once installed, the maintenance cost is very low. It is eco-friendly, safely fitting into our society without any disturbance. Producing electricity from the Sun requires the installation of solar panels, which incurs a huge initial cost and requires large areas of lands for installation. This is where nanotechnology comes into the picture and serves the purpose of increasing the efficiency to higher levels, thus bringing down the overall cost for energy production. Also, emerging low-cost solar cell technologies, e.g. thin film technologies and dye-sensitized solar cells (DSCs) help to replace the use of silicon, which is expensive. Again, nanotechnological implications can be applied in these solar cells, to achieve higher efficiencies. This paper vividly deals with the various available solar cells, choosing DSCs as the most appropriate ones. The nanotechnological implications which help to improve their performance are dealt with, in detail. Additionally, the

  17. On global energy scenario, dye-sensitized solar cells and the promise of nanotechnology.

    PubMed

    Reddy, K Govardhan; Deepak, T G; Anjusree, G S; Thomas, Sara; Vadukumpully, Sajini; Subramanian, K R V; Nair, Shantikumar V; Nair, A Sreekumaran

    2014-04-21

    One of the major problems that humanity has to face in the next 50 years is the energy crisis. The rising population, rapidly changing life styles of people, heavy industrialization and changing landscape of cities have increased energy demands, enormously. The present annual worldwide electricity consumption is 12 TW and is expected to become 24 TW by 2050, leaving a challenging deficit of 12 TW. The present energy scenario of using fossil fuels to meet the energy demand is unable to meet the increase in demand effectively, as these fossil fuel resources are non-renewable and limited. Also, they cause significant environmental hazards, like global warming and the associated climatic issues. Hence, there is an urgent necessity to adopt renewable sources of energy, which are eco-friendly and not extinguishable. Of the various renewable sources available, such as wind, tidal, geothermal, biomass, solar, etc., solar serves as the most dependable option. Solar energy is freely and abundantly available. Once installed, the maintenance cost is very low. It is eco-friendly, safely fitting into our society without any disturbance. Producing electricity from the Sun requires the installation of solar panels, which incurs a huge initial cost and requires large areas of lands for installation. This is where nanotechnology comes into the picture and serves the purpose of increasing the efficiency to higher levels, thus bringing down the overall cost for energy production. Also, emerging low-cost solar cell technologies, e.g. thin film technologies and dye-sensitized solar cells (DSCs) help to replace the use of silicon, which is expensive. Again, nanotechnological implications can be applied in these solar cells, to achieve higher efficiencies. This paper vividly deals with the various available solar cells, choosing DSCs as the most appropriate ones. The nanotechnological implications which help to improve their performance are dealt with, in detail. Additionally, the

  18. Improved solar efficiency by introducing graphene oxide in purple cabbage dye sensitized TiO2 based solar cell

    NASA Astrophysics Data System (ADS)

    Al-Ghamdi, Ahmed A.; Gupta, R. K.; Kahol, P. K.; Wageh, S.; Al-Turki, Y. A.; El Shirbeeny, W.; Yakuphanoglu, F.

    2014-04-01

    Natural dye extracted from purple cabbage was used for fabrication of TiO2 dye-sensitized solar cells (DSSCs). The effect of light intensity on the solar efficiency of the device was investigated. It was observed that the efficiency of the DSSC increases with increasing the light intensity e.g. the efficiency of the solar cell increases from 0.013±0.002% to 0.150±0.020% by increase in light intensity from 30 to 100 mW/cm2, respectively. The solar efficiency of the natural dye used in this research was compared with commercial dye (N 719) under similar experimental conditions and observed that the natural (purple cabbage) dye has higher efficiency (0.150±0.020%) than N 719 (0.078±0.002%). It was further evaluated that the efficiency of the fabricated solar cell could improve by incorporating graphene oxide. The efficiency of the TiO2 dye-sensitized solar cell was found to increase from 0.150±0.020% to 0.361±0.009% by incorporating graphene oxide into purple cabbage dye.

  19. Photoelectrochemical characteristics of dye-sensitized solar cells incorporating innovative and inexpensive materials

    NASA Astrophysics Data System (ADS)

    Harlow, Lisa Jean

    The use of energy is going to continue to increase rapidly due to population and economic advances occurring throughout the world. The most widely used energies produce carbon dioxide during their combustion and have finite limits on how much of these resources are available. A strong push to utilizing renewable energy is necessary to keep up with the demand. The only renewable energy that has unlimited supply is solar. Our goal is to find cost-effective alternatives to historically the most extensively used materials in dye-sensitized solar cells. In order to rely on efficiency changes coinciding with the introduction of a new component, a standard baseline of performance is necessary to establish. A reproducible fabrication procedure composed of standard materials was instituted; the efficiency parameters exhibited a less than 10% standard deviation for any set of solar cells. Any modifications to the cell components would be apparent in the change in efficiency. Our cell modifications focused on economical alternatives to the electrolyte, the counter electrode and the chromophore. Solution-based electrolytes were replaced with a non-volatile ionic liquid, 1-methyl-3-propylimidazolium iodide, and then a poly(imidazole-functionalized) silica nanoparticle. Solid-state electrolytes reduce or prevent leakage and could ease manufacturing in large-scale devices. Platinum has been the counter electrode catalyst primarily used with the iodide/triiodide redox couple, but is a rare metal making it rather costly. We reduce platinum loading by introducing a novel counter electrode that employs platinum nanoparticles embedded on a graphene nanoplatelet paper. The highly conductive carbon base also negates the use of the expensive conductive substrate necessary for the platinum catalyst, further reducing cost. We also study the differences in transitioning from ruthenium polypyridyls to iron-based chromophores in dye-sensitized solar cells. Iron introduces low-lying ligand

  20. Bifacial dye-sensitized solar cells with enhanced rear efficiency and power output

    NASA Astrophysics Data System (ADS)

    Cai, Hongyuan; Tang, Qunwei; He, Benlin; Li, Ru; Yu, Liangmin

    2014-11-01

    Pursuing a high power conversion efficiency with no sacrifice of cost-effectiveness has been a persistent objective for dye-sensitized solar cells (DSSCs). One promising solution to this impasse is increased light harvesting. Previous efforts in light harvesting have been made on setting blocking layers or reflecting layers, or adding a light harvester, resulting in tedious procedures without reducing the expenses. We present a mild solution strategy for synthesizing transparent Ru-Se alloy counter electrodes (CEs) for bifacial DSSC applications, displaying optimal front and rear efficiencies of 8.76% and 5.90%, respectively. In comparison with pristine Pt-based solar cells, the maximum power output has also been markedly enhanced. Moreover, fast start-up, high multiple start capability, and good stability are observed in the bifacial DSSCs with transparent Ru-Se binary alloy electrodes. The impressive efficiencies along with simple preparation of the cost-effective Ru-Se alloy CEs demonstrates their potential application in robust DSSCs.Pursuing a high power conversion efficiency with no sacrifice of cost-effectiveness has been a persistent objective for dye-sensitized solar cells (DSSCs). One promising solution to this impasse is increased light harvesting. Previous efforts in light harvesting have been made on setting blocking layers or reflecting layers, or adding a light harvester, resulting in tedious procedures without reducing the expenses. We present a mild solution strategy for synthesizing transparent Ru-Se alloy counter electrodes (CEs) for bifacial DSSC applications, displaying optimal front and rear efficiencies of 8.76% and 5.90%, respectively. In comparison with pristine Pt-based solar cells, the maximum power output has also been markedly enhanced. Moreover, fast start-up, high multiple start capability, and good stability are observed in the bifacial DSSCs with transparent Ru-Se binary alloy electrodes. The impressive efficiencies along with

  1. Graphene supported nickel nanoparticle as a viable replacement for platinum in dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Bajpai, Reeti; Roy, Soumyendu; Kulshrestha, Neha; Rafiee, Javad; Koratkar, Nikhil; Misra, D. S.

    2012-01-01

    A platinum free counter electrode for dye sensitized solar cells was developed using graphene platelets (GP) supported nickel nanoparticles (NPs) as the active catalyst. Few layered GP were prepared by chemical oxidation of graphite powders followed by thermal exfoliation and reduction. The nanoparticles of nickel were deposited directly onto the platelets by pulsed laser ablation. The composite electrodes of GP and Ni nanoparticles (GP-Ni) thus obtained showed better performance compared to conventional Pt thin film electrodes (Std Pt) and unsupported Ni NPs. The efficiencies of the cells fabricated using GP-Ni, Std Pt and Ni NP CEs were 2.19%, 2% and 1.62%, respectively. The GP-Ni composite solar cell operated with an open circuit voltage of 0.7 V and a fill factor of 0.6. Electrochemical impedance spectroscopy using the I3-/I- redox couple confirms lower values of charge transfer resistance for the composite electrodes, 4.67 Ω cm2 as opposed to 7.73 Ω cm2 of Std Pt. The better catalytic capability of these composite materials is also reflected in the stronger I3- reduction peaks in cyclic voltammetry scans.A platinum free counter electrode for dye sensitized solar cells was developed using graphene platelets (GP) supported nickel nanoparticles (NPs) as the active catalyst. Few layered GP were prepared by chemical oxidation of graphite powders followed by thermal exfoliation and reduction. The nanoparticles of nickel were deposited directly onto the platelets by pulsed laser ablation. The composite electrodes of GP and Ni nanoparticles (GP-Ni) thus obtained showed better performance compared to conventional Pt thin film electrodes (Std Pt) and unsupported Ni NPs. The efficiencies of the cells fabricated using GP-Ni, Std Pt and Ni NP CEs were 2.19%, 2% and 1.62%, respectively. The GP-Ni composite solar cell operated with an open circuit voltage of 0.7 V and a fill factor of 0.6. Electrochemical impedance spectroscopy using the I3-/I- redox couple confirms lower

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

    PubMed

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

    2015-01-01

    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. Higher Efficiency for Quasi-Solid State Dye Sensitized Solar Cells Under Low Light Irradiance

    NASA Astrophysics Data System (ADS)

    Desilva, Ajith; Bandara, T. M. W. J.; Fernado, H. D. N. S.; Fernando, P. S. L.; Dissanayake, M. A. K. L.; Jayasundara, W. J. M. J. S. R.; Furlani, M.; Mellander, B.-E.

    2014-03-01

    Dye-sensitized solar cells (DSSCs), lower cost solar energy conversion devices are alternative green energy source. The liquid based electrolyte DSSCs have higher efficiencies with many practical issues while the quasi-solid-state DSSCs resolve the key problems but efficiencies are relatively low. Polyacrylonitrile (PAN) based gel polymer electrolytes were fabricated as DSSCs by incorporating ethylene carbonate and propylene carbonate plasticizers and tetrapropylammonium iodide salt. A thin layer of electrolyte was sandwiched between the TiO2 anode (sensitized with N719 dye) and the Pt counter electrode. The electrolyte had an ionic conductivity of 2.6 mS/cm at 25 degrees of Celsius. DSSCs incorporating this gel electrolyte revealed Vsc circuit, Jsc, fill factor (FF) and efficiency values of 0.71 V, 11.8 mA, 51 percent and 4.2 percent respectively under 1 sun irradiation. The efficiency of the cell increased with decreasing solar irradiance achieving up to 10 percent efficiency and 80 percent FF at low irradiance values. This work uncovers that quasi-solid state DSSCs can reach efficiencies close to that of liquid electrolytes based cells.

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

    PubMed Central

    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

    2015-01-01

    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. PMID:26538097

  5. A methodology for improving laser beam induced current images of dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Navas, Francisco Javier; Alcántara, Rodrigo; Fernández-Lorenzo, Concha; Martín, Joaquín

    2009-06-01

    Using the laser beam induced current (LBIC) technique for the study of solar cells and photovoltaic devices, it is possible to obtain images representing the different degrees of quantum efficiency observed on the surface of these elements. Dye sensitized solar cells (DSSCs) or photoelectrochemical solar cells, in contrast to those based on solid-solid interfaces, show a slow response to irradiance variations—up to tens of seconds. This is basically due to both viscous matter transport processes and load transfer. This response is inappreciable when the device is functioning continuously but when a LBIC scan is performed, in which the laser moves quickly from one point to another, the slow response produces a memory effect and the signal generated at one given point depends on the conversion efficiency coefficients of the previously excited positions, resulting in diffuse images and a lack of sharpness. This work presents a methodology to correct high-resolution LBIC mappings of DSSCs using an algorithm based on the kinetics of the discharge process of the irradiated zone. The validity of the proposed method has been evaluated by carrying out experiments where the algorithm has been applied to LBIC mappings.

  6. Investigation of the influence of coadsorbent dye upon the interfacial structure of dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Honda, M.; Yanagida, M.; Han, L.; Miyano, K.

    2014-11-01

    The interface between Ru(tcterpy)(NCS)3TBA2 [black dye (BD); tcterpy = 4,4',4″-tricarboxy-2,2':6',2″-terpyridine, NCS = thiocyanato, TBA = tetrabutylammonium cation] and nanocrystalline TiO2, as found in dye-sensitized solar cells, is investigated by soft-X-ray synchrotron radiation and compared with the adsorption structure of cis-Ru(Hdcbpy)2(NCS)2TBA2 (N719; dcbpy = 4,4'-dicarboxy-2,2'-bipyridine) on TiO2 to elucidate the relationship between the adsorption mode of BD and the photocurrent with and without coadsorbed indoline dye D131. The depth profile is characterized with X-ray photoelectron spectroscopy and S K-edge X-ray absorption fine structure using synchrotron radiation. Both datasets indicate that one of the isothiocyanate groups of BD interacts with TiO2 via its S atom when the dye is adsorbed from a single-component solution. In contrast, the interaction is slightly suppressed when D131 is coadsorbed, indicated by the fact that the presence of D131 changes the adsorption mode of BD. Based upon these results, the number of BD dye molecules interacting with the substrate is shown to decrease by 10% when D131 is coadsorbed, and the dissociation is shown to be related to the short-circuit photocurrent in the 600-800 nm region. The design of a procedure to promote the preferential adsorption of D131 therefore leads to an improvement of the short-circuit current and conversion efficiency.

  7. Performance Enhancement of Dye-Sensitized Solar Cells Based on TiO₂ Thick Mesoporous Photoanodes by Morphological Manipulation.

    PubMed

    Keshavarzi, Reza; Mirkhani, Valiollah; Moghadam, Majid; Tangestaninejad, Shahram; Mohammadpoor-Baltork, Iraj

    2015-10-27

    This study is an attempt to give an account of the preparation of mesoporous TiO2 thick templated films of nonsimilar pore architecture and their use in dye-sensitized solar cells (DSSCs). Highly crystallized mesoporous titania thick templated films with four different morphologies including hexagonal, wormlike, cubic, and gridlike mesostructure, have been successfully synthesized through an evaporation-induced self-assembly (EISA) route followed by layer-by-layer deposition. Stabilization, followed by each coating, and calcinations, carried out after every five layers, were used to produce crack-free thick films. These mesoporous templated titanium dioxide samples were characterized by TEM, XRD, SEM, BET, and UV-vis measurements and used as a photoelectrode material in DSSCs. The mesostructured films with a thickness of about 7 μm demonstrated better performance in comparison to nanocrystalline TiO2 films (NC-TiO2) at a film thickness of 13 μm as the most typical films utilized in DSSCs. The findings reveal that a surfactant/Ti ratio change undergone for developing cubic mesostructures can enhance the crystallinity and roughness factor and therefore increase the energy conversion efficiency of DSSC. The cell performances derived from these mesofilms were enhanced compared to the efficiencies reported thus far. The best photovoltaic performance of 8.73% came from DSSC using the cubic mesoporous TiO2 photoelectrode with the following properties: open circuit voltage of 743 mV, short circuit photocurrent density of 16.35 mA/cm(2), and fill factor of 0.72.

  8. Plasmonic-resonance-based ternary composite complementary enhancement of the performance of dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Bai, Lihua; Li, Meiya; Liu, Xiaolian; Luoshan, Mengdai; Zhang, Feng; Guo, Kaimo; Zhu, Yongdan; Sun, Beilei; Zhao, Xingzhong

    2016-10-01

    Graphene (G), TiO2 fusiform nanorods (TiO2NRs) adsorbed with Au nanoparticles (AuNPs) are prepared and blended as multifunctional materials into TiO2 nanocrystalline film to form a novel ternary (G-TiO2NRs-Au) composite photoanode in dye-sensitized solar cells (DSSCs). The effects of G-TiO2NRs-Au on the properties of the photoanode and DSSC are investigated. Results show that, by blending G-TiO2NRs-Au, the light absorption and scattering of the photoanode are obviously improved, and the charge transfer resistance R2 and electron recombination are decreased, resulting in a significant enhancement in the short-circuit current density (J sc) and the photoelectric conversion efficiency (PCE) of the DSSCs. The maximum J sc of 17.66 mA cm-2 and PCE of 8.56% are obtained in the optimal G-TiO2NRs-Au-based DSSC, about 33.6% and 35.0% higher than that obtained in the conventional TiO2-based DSSC. This significant improvement in the performance of the DSSC can be attributed to the ternary composite complementary effects of multi-functions from the surface plasmon resonance of AuNPs, light scattering of TiO2NRs, and the improved dye loading and fast electron transmission channel from graphene. This study provides an effective way of ternary composite complementary enhancement of the J sc and PCE of the DSSCs.

  9. Plasmonic-resonance-based ternary composite complementary enhancement of the performance of dye-sensitized solar cells.

    PubMed

    Bai, Lihua; Li, Meiya; Liu, Xiaolian; Luoshan, Mengdai; Zhang, Feng; Guo, Kaimo; Zhu, Yongdan; Sun, Beilei; Zhao, Xingzhong

    2016-10-14

    Graphene (G), TiO2 fusiform nanorods (TiO2NRs) adsorbed with Au nanoparticles (AuNPs) are prepared and blended as multifunctional materials into TiO2 nanocrystalline film to form a novel ternary (G-TiO2NRs-Au) composite photoanode in dye-sensitized solar cells (DSSCs). The effects of G-TiO2NRs-Au on the properties of the photoanode and DSSC are investigated. Results show that, by blending G-TiO2NRs-Au, the light absorption and scattering of the photoanode are obviously improved, and the charge transfer resistance R2 and electron recombination are decreased, resulting in a significant enhancement in the short-circuit current density (J sc) and the photoelectric conversion efficiency (PCE) of the DSSCs. The maximum J sc of 17.66 mA cm(-2) and PCE of 8.56% are obtained in the optimal G-TiO2NRs-Au-based DSSC, about 33.6% and 35.0% higher than that obtained in the conventional TiO2-based DSSC. This significant improvement in the performance of the DSSC can be attributed to the ternary composite complementary effects of multi-functions from the surface plasmon resonance of AuNPs, light scattering of TiO2NRs, and the improved dye loading and fast electron transmission channel from graphene. This study provides an effective way of ternary composite complementary enhancement of the J sc and PCE of the DSSCs. PMID:27595326

  10. Mesoporous TiO2 Bragg Stack Templated by Graft Copolymer for Dye-sensitized Solar Cells

    PubMed Central

    Park, Jung Tae; Chi, Won Seok; Kim, Sang Jin; Lee, Daeyeon; Kim, Jong Hak

    2014-01-01

    Organized mesoporous TiO2 Bragg stacks (om-TiO2 BS) consisting of alternating high and low refractive index organized mesoporous TiO2 (om-TiO2) films were prepared to enhance dye loading, light harvesting, electron transport, and electrolyte pore-infiltration in dye-sensitized solar cells (DSSCs). The om-TiO2 films were synthesized via a sol-gel reaction using amphiphilic graft copolymers consisting of poly(vinyl chloride) backbones and poly(oxyethylene methacrylate) side chains, i.e., PVC-g-POEM as templates. To generate high and low index films, the refractive index of om-TiO2 film was tuned by controlling the grafting ratio of PVC-g-POEM via atomic transfer radical polymerization (ATRP). A polymerized ionic liquid (PIL)-based DSSC fabricated with a 1.2-μm-thick om-TiO2 BS-based photoanode exhibited an efficiency of 4.3%, which is much higher than that of conventional DSSCs with a nanocrystalline TiO2 layer (nc-TiO2 layer) (1.7%). A PIL-based DSSC with a heterostructured photoanode consisting of 400-nm-thick organized mesoporous TiO2 interfacial (om-TiO2 IF) layer, 7-μm-thick nc-TiO2, and 1.2-μm-thick om-TiO2 BS as the bottom, middle and top layers, respectively, exhibited an excellent efficiency of 7.5%, which is much higher than that of nanocrystaline TiO2 photoanode (3.5%). PMID:24980936

  11. Plasmonic-resonance-based ternary composite complementary enhancement of the performance of dye-sensitized solar cells.

    PubMed

    Bai, Lihua; Li, Meiya; Liu, Xiaolian; Luoshan, Mengdai; Zhang, Feng; Guo, Kaimo; Zhu, Yongdan; Sun, Beilei; Zhao, Xingzhong

    2016-10-14

    Graphene (G), TiO2 fusiform nanorods (TiO2NRs) adsorbed with Au nanoparticles (AuNPs) are prepared and blended as multifunctional materials into TiO2 nanocrystalline film to form a novel ternary (G-TiO2NRs-Au) composite photoanode in dye-sensitized solar cells (DSSCs). The effects of G-TiO2NRs-Au on the properties of the photoanode and DSSC are investigated. Results show that, by blending G-TiO2NRs-Au, the light absorption and scattering of the photoanode are obviously improved, and the charge transfer resistance R2 and electron recombination are decreased, resulting in a significant enhancement in the short-circuit current density (J sc) and the photoelectric conversion efficiency (PCE) of the DSSCs. The maximum J sc of 17.66 mA cm(-2) and PCE of 8.56% are obtained in the optimal G-TiO2NRs-Au-based DSSC, about 33.6% and 35.0% higher than that obtained in the conventional TiO2-based DSSC. This significant improvement in the performance of the DSSC can be attributed to the ternary composite complementary effects of multi-functions from the surface plasmon resonance of AuNPs, light scattering of TiO2NRs, and the improved dye loading and fast electron transmission channel from graphene. This study provides an effective way of ternary composite complementary enhancement of the J sc and PCE of the DSSCs.

  12. Investigation of the influence of coadsorbent dye upon the interfacial structure of dye-sensitized solar cells

    SciTech Connect

    Honda, M. Miyano, K.; Yanagida, M.; Han, L.

    2014-11-07

    The interface between Ru(tcterpy)(NCS){sub 3}TBA{sub 2} [black dye (BD); tcterpy = 4,4{sup ′},4{sup ″}-tricarboxy-2,2{sup ′}:6{sup ′},2{sup ″}-terpyridine, NCS = thiocyanato, TBA = tetrabutylammonium cation] and nanocrystalline TiO{sub 2}, as found in dye-sensitized solar cells, is investigated by soft-X-ray synchrotron radiation and compared with the adsorption structure of cis-Ru(Hdcbpy){sub 2}(NCS){sub 2}TBA{sub 2} (N719; dcbpy = 4,4{sup ′}-dicarboxy-2,2{sup ′}-bipyridine) on TiO{sub 2} to elucidate the relationship between the adsorption mode of BD and the photocurrent with and without coadsorbed indoline dye D131. The depth profile is characterized with X-ray photoelectron spectroscopy and S K-edge X-ray absorption fine structure using synchrotron radiation. Both datasets indicate that one of the isothiocyanate groups of BD interacts with TiO{sub 2} via its S atom when the dye is adsorbed from a single-component solution. In contrast, the interaction is slightly suppressed when D131 is coadsorbed, indicated by the fact that the presence of D131 changes the adsorption mode of BD. Based upon these results, the number of BD dye molecules interacting with the substrate is shown to decrease by 10% when D131 is coadsorbed, and the dissociation is shown to be related to the short-circuit photocurrent in the 600–800 nm region. The design of a procedure to promote the preferential adsorption of D131 therefore leads to an improvement of the short-circuit current and conversion efficiency.

  13. Mesoporous TiO2 Nanowire Film for Dye-Sensitized Solar Cell.

    PubMed

    Xiao, Li; Xu, Jia; Liu, Xiu; Zhang, Yongzhe; Zhang, Bing; Yao, Jianxi; Dai, Songyuan; Tan, Zhanao; Pan, Xu

    2016-06-01

    In this work, TiO2 nanowire arrays were grown on fluorine-doped tin oxide (FTO) glass substrate, and then were converted into mesoporous nanowires (MNWs). The TiO2 MNWs are about 5 μm in length and 30-200 nm in diameter, with mesopores size of 5-30 nm randomly distributed on the NW surface. X-ray diffraction pattern reports show that the NWs are single crystallized rutile TiO2 and oriented grown along [001]. Through further characterization of FT-IR and TG-DSC, we proposed a reasonable explanation for pore existence. After dye-sensitized solar cells (DSSCs) assembly, the photoelectric conversion efficiency (PCE) of MNWs based DSSC achieved 3.2%. It means tenfold enhancement of photoelectric property compare with the as-grown NWs. Furthermore, dye absorb capacity of MNWs can reach up to 4.11 x 10(-8) mol/cm2. However, such MNWs can not only provide quick and efficient electron transmission channel, but also owns big specific surface area to absorb abundant dyes, thus conducive to fabricate solar cell with a high PCE.

  14. Carbon nanofiber-based counter electrodes for low cost dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Sebastián, D.; Baglio, V.; Girolamo, M.; Moliner, R.; Lázaro, M. J.; Aricò, A. S.

    2014-03-01

    Carbon materials represent an attractive alternative to platinum in dye-sensitized solar cells (DSSC) counter electrodes to contribute to an efficient conversion of solar energy into electricity. The use of highly graphitic carbon nanofibers (CNFs) is investigated by analyzing the effect of the filament diameter, surface area and graphitization degree on the DSSC cathode performance. To this purpose, transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman spectroscopy and physisorption analysis are used to characterize the main properties of the CNFs. The behavior of CNFs as counter electrodes in DSSC is investigated by polarization experiments and electrochemical impedance spectroscopy. Among the different materials, the CNF characterized by the highest surface area (183 m2 g-1), thinnest filament size (24 nm) and highest density of surface defects shows the best performance in terms of efficiency, open circuit potential and short circuit current density. Further investigation of the electrode thickness together with series and charge transfer resistance cross-analysis evidences the key role played by the surface area and surface graphitization to obtain a suitable performance. Compared to literature, so-obtained CNFs represent an interesting alternative to manufacture low cost DSSC cathodes.

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

    NASA Astrophysics Data System (ADS)

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

    2016-04-01

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

  16. Bifacial dye-sensitized solar cells with enhanced rear efficiency and power output.

    PubMed

    Cai, Hongyuan; Tang, Qunwei; He, Benlin; Li, Ru; Yu, Liangmin

    2014-12-21

    Pursuing a high power conversion efficiency with no sacrifice of cost-effectiveness has been a persistent objective for dye-sensitized solar cells (DSSCs). One promising solution to this impasse is increased light harvesting. Previous efforts in light harvesting have been made on setting blocking layers or reflecting layers, or adding a light harvester, resulting in tedious procedures without reducing the expenses. We present a mild solution strategy for synthesizing transparent Ru-Se alloy counter electrodes (CEs) for bifacial DSSC applications, displaying optimal front and rear efficiencies of 8.76% and 5.90%, respectively. In comparison with pristine Pt-based solar cells, the maximum power output has also been markedly enhanced. Moreover, fast start-up, high multiple start capability, and good stability are observed in the bifacial DSSCs with transparent Ru-Se binary alloy electrodes. The impressive efficiencies along with simple preparation of the cost-effective Ru-Se alloy CEs demonstrates their potential application in robust DSSCs.

  17. Transparent metal selenide alloy counter electrodes for high-efficiency bifacial dye-sensitized solar cells.

    PubMed

    Duan, Yanyan; Tang, Qunwei; Liu, Juan; He, Benlin; Yu, Liangmin

    2014-12-22

    The exploration of cost-effective and transparent counter electrodes (CEs) is a persistent objective in the development of bifacial dye-sensitized solar cells (DSSCs). Transparent counter electrodes based on binary-alloy metal selenides (M-Se; M=Co, Ni, Cu, Fe, Ru) are now obtained by a mild, solution-based method and employed in efficient bifacial DSSCs. Owing to superior charge-transfer ability for the I(-) /I3 (-) redox couple, electrocatalytic activity toward I3 (-) reduction, and optical transparency, the bifacial DSSCs with CEs consisting of a metal selenide alloy yield front and rear efficiencies of 8.30 % and 4.63 % for Co0.85 Se, 7.85 % and 4.37 % for Ni0.85 Se, 6.43 % and 4.24 % for Cu0.50 Se, 7.64 % and 5.05 % for FeSe, and 9.22 % and 5.90 % for Ru0.33 Se in comparison with 6.18 % and 3.56 % for a cell with an electrode based on pristine platinum, respectively. Moreover, fast activity onset, high multiple start/stop capability, and relatively good stability demonstrate that these new electrodes should find applications in solar panels.

  18. Interfacial charge transfer mechanisms and cation effects in dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Staniszewski, Aaron J.

    The contents herein this thesis report on mechanistic processes important for the dye-sensitized solar cell (DSSC) with a focus on the influential nature of small cations at the interface. Chapter 1 introduces the reader to the DSSC by describing the accepted mechanism of a functioning cell and detailing its working components. Chapter 2 reports on a novel strategy aimed to improve device efficiencies and exceed the Shockley-Queisser limit, a well-known theoretical solar-to-electrical energy conversion efficiency standard. This strategy uses the ultrafast electron injection properties of the TiO2 to produce products from sunlight that are uphill in fluid solution. In Chapter 3, the mechanism of recombination of this charge-separated state is studied using chronoabsorption measurements. It is proposed that while the hole transport is limited through self-exchange reactions, the conduction band states of TiO2 mediate electron transport. Potential determining cations were introduced to "tune" the electron diffusion rates. Chapter 4 reports on a high-extinction ruthenium compound for its use as a sensitizer. Interestingly, after photo-oxidation of this compound on TiO2, the hole transferred out to a remote ligand, increasing the charge separation distance. Cation motion was studied in Chapter 5 using a novel ruthenium(II) compound that underwent large spectroscopic changes when exposed to lithium cations. These absorption changes allowed the determination of its transport mechanism at the interface during electron injection and charge recombination.

  19. Fluorine doped-tin oxide prepared using spray method for dye sensitized solar cell application

    NASA Astrophysics Data System (ADS)

    Widiyandari, Hendri; Purwanto, Agus; Diharjo, Kuncoro; Suyitno, Hidayanto, Eko

    2013-09-01

    Fluorine-doped Tin Oxide (FTO) film was fabricated by spray deposition method. FTO films were prepared in different sheet resistance 6.7, 12.1, 19.3, and 23.5 Ω/sq. X-ray diffractograms showed that the as-grown FTO film was tetragonal SnO2. The prepared FTO film have an average transmittance of 80% in the visible region (λ=400-800 nm). These FTO films were then used to fabricate Dye Sensitized Solar Cell (DSSC). The working electrode was made from TiO2 paste using doctor blade technique. DSSC samples were characterized using solar simulator under AM 1.5 (100 mW/cm2). It is found that the efficiency of DSSC was much affected by sheet resistance of FTO film. The efficiency of DCCS was 2.32, 2.4, 1.1 and 0.97 (%) for the FTO sheet resistance 6.7, 12.1, 19.3, and 23.5 Ω/sq, respectively. It is shown that the optimum DSSC efficiency was made from FTO with sheet resistance 12.1 Ω/sq.

  20. Bifacial dye-sensitized solar cells with transparent cobalt selenide alloy counter electrodes

    NASA Astrophysics Data System (ADS)

    Duan, Yanyan; Tang, Qunwei; He, Benlin; Zhao, Zhiyuan; Zhu, Ling; Yu, Liangmin

    2015-06-01

    High power conversion efficiency and cost-effectiveness are two persistent objectives for dye-sensitized solar cell (DSSC). Electricity generation from either front or rear side of a bifacial DSSC has been considered as a facile avenue of bringing down the cost of solar-to-electric conversion. Therefore, the fabrication of a transparent counter electrode (CE) with a high electrocatalytic activity is a prerequisite to realize this goal. We present here the feasibility of utilizing transparent cobalt selenide (Co-Se) binary alloy counter electrode for bifacial DSSC application, in which binary Co-Se alloy electrode is synthesized by a mild solution strategy and the cell device is irradiated by either front or rear side. Due to the high optical transparency, charge-transfer ability, and electrocatalytic activity, maximum front and rear efficiencies of 8.30% and 4.63% are recorded under simulated air mass 1.5 (AM1.5) irradiation, respectively. The impressive efficiency along with fast start-up, multiple start capability, and simple preparation highlights the potential application of cost-effective and transparent Co-Se alloy CE in robust bifacial DSSCs.

  1. Three-dimensional double deck meshlike dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Wang, Yuanhao; Yang, Hongxing; Lu, Lin

    2010-09-01

    In this paper, we develop a new type of three-dimensional dye-sensitized solar cells (3D DSSCs) with double deck cylindrical Ti meshes as the substrates. One of the Ti meshes is anodized to in situ synthesize the self-organized TiO2 nanotube layer as the photoanode materials. Another Ti mesh is platinized through electrodeposition as the counter electrode. The morphologies of the electrodes are characterized by scanning electron microscopy. We investigate the effect of the mesh number on the 3D DSSCs with the dye adsorption, cyclic voltammetry, and electrochemical impedance spectroscopy. The results show that with the increase in the mesh number, the dye-loadings on the photoanode and the active surface area of Pt on the counter electrode are increased, while the diffusion of the electrolyte becomes more difficult due to the reduced diameter of the openings in the mesh. It has also been demonstrated that the performance of this 3D DSSC is independent of the incident solar beam angle due to its axial symmetrical structure. In the I-V measurement, the 3D DSSC based on the 90-mesh photoanode and the 120-mesh counter electrode shows the highest conversion efficiency of 5.5% under standard AM 1.5 sunlight. The problems of electrical insulator layer are discussed and further investigation is expected.

  2. π-Spacer effect in dithiafulvenyl-π-phenothiazine dyes for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaofeng; Gou, Faliang; Zhao, Dongning; Shi, Jian; Gao, Hong; Zhu, Zhenping; Jing, Huanwang

    2016-08-01

    New dithiafulvenyl-π-phenothiazine dyes have been devised and prepared for dye-sensitized solar cells. Various π-spacers have been successfully introduced into the skeleton of dithiafulvenyl and phenothiazine unit to generate novel D-π-D-A dyes (DPP-1 ∼ 4). All dyes have been characterized with NMR, HRMS, UV-vis and fluorescence spectra, and taken into cyclic voltammetry measurements. The devices of new dyes have been determined by photoelectrochemical experiments (IV, IPCE and EIS), in which, solar cell of DPP-4 with biphenyl ring π-spacer enhances obviously its photoelectric conversion efficiency to 7.66% reaching 94% of N719-based standard cell and displays good long-term stability with quasi-solid-state electrolyte. Density functional theory (DFT) calculations of new dyes provide further insight into the molecular geometries and the impacts of the torsion angles on their photovoltaic performance. Large dihedral angles in DPP dyes induce good charge separation for efficient unidirectional flow of electron from donor to acceptor.

  3. Transparent metal selenide alloy counter electrodes for high-efficiency bifacial dye-sensitized solar cells.

    PubMed

    Duan, Yanyan; Tang, Qunwei; Liu, Juan; He, Benlin; Yu, Liangmin

    2014-12-22

    The exploration of cost-effective and transparent counter electrodes (CEs) is a persistent objective in the development of bifacial dye-sensitized solar cells (DSSCs). Transparent counter electrodes based on binary-alloy metal selenides (M-Se; M=Co, Ni, Cu, Fe, Ru) are now obtained by a mild, solution-based method and employed in efficient bifacial DSSCs. Owing to superior charge-transfer ability for the I(-) /I3 (-) redox couple, electrocatalytic activity toward I3 (-) reduction, and optical transparency, the bifacial DSSCs with CEs consisting of a metal selenide alloy yield front and rear efficiencies of 8.30 % and 4.63 % for Co0.85 Se, 7.85 % and 4.37 % for Ni0.85 Se, 6.43 % and 4.24 % for Cu0.50 Se, 7.64 % and 5.05 % for FeSe, and 9.22 % and 5.90 % for Ru0.33 Se in comparison with 6.18 % and 3.56 % for a cell with an electrode based on pristine platinum, respectively. Moreover, fast activity onset, high multiple start/stop capability, and relatively good stability demonstrate that these new electrodes should find applications in solar panels. PMID:25358619

  4. Mesoporous TiO2 Nanowire Film for Dye-Sensitized Solar Cell.

    PubMed

    Xiao, Li; Xu, Jia; Liu, Xiu; Zhang, Yongzhe; Zhang, Bing; Yao, Jianxi; Dai, Songyuan; Tan, Zhanao; Pan, Xu

    2016-06-01

    In this work, TiO2 nanowire arrays were grown on fluorine-doped tin oxide (FTO) glass substrate, and then were converted into mesoporous nanowires (MNWs). The TiO2 MNWs are about 5 μm in length and 30-200 nm in diameter, with mesopores size of 5-30 nm randomly distributed on the NW surface. X-ray diffraction pattern reports show that the NWs are single crystallized rutile TiO2 and oriented grown along [001]. Through further characterization of FT-IR and TG-DSC, we proposed a reasonable explanation for pore existence. After dye-sensitized solar cells (DSSCs) assembly, the photoelectric conversion efficiency (PCE) of MNWs based DSSC achieved 3.2%. It means tenfold enhancement of photoelectric property compare with the as-grown NWs. Furthermore, dye absorb capacity of MNWs can reach up to 4.11 x 10(-8) mol/cm2. However, such MNWs can not only provide quick and efficient electron transmission channel, but also owns big specific surface area to absorb abundant dyes, thus conducive to fabricate solar cell with a high PCE. PMID:27427603

  5. Graphene supported nickel nanoparticle as a viable replacement for platinum in dye sensitized solar cells.

    PubMed

    Bajpai, Reeti; Roy, Soumyendu; kulshrestha, Neha; Rafiee, Javad; Koratkar, Nikhil; Misra, D S

    2012-02-01

    A platinum free counter electrode for dye sensitized solar cells was developed using graphene platelets (GP) supported nickel nanoparticles (NPs) as the active catalyst. Few layered GP were prepared by chemical oxidation of graphite powders followed by thermal exfoliation and reduction. The nanoparticles of nickel were deposited directly onto the platelets by pulsed laser ablation. The composite electrodes of GP and Ni nanoparticles (GP-Ni) thus obtained showed better performance compared to conventional Pt thin film electrodes (Std Pt) and unsupported Ni NPs. The efficiencies of the cells fabricated using GP-Ni, Std Pt and Ni NP CEs were 2.19%, 2% and 1.62%, respectively. The GP-Ni composite solar cell operated with an open circuit voltage of 0.7 V and a fill factor of 0.6. Electrochemical impedance spectroscopy using the I(3)(-)/I(-) redox couple confirms lower values of charge transfer resistance for the composite electrodes, 4.67 Ω cm(2) as opposed to 7.73 Ω cm(2) of Std Pt. The better catalytic capability of these composite materials is also reflected in the stronger I(3)(-) reduction peaks in cyclic voltammetry scans. PMID:22193832

  6. π-Spacer effect in dithiafulvenyl-π-phenothiazine dyes for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaofeng; Gou, Faliang; Zhao, Dongning; Shi, Jian; Gao, Hong; Zhu, Zhenping; Jing, Huanwang

    2016-08-01

    New dithiafulvenyl-π-phenothiazine dyes have been devised and prepared for dye-sensitized solar cells. Various π-spacers have been successfully introduced into the skeleton of dithiafulvenyl and phenothiazine unit to generate novel D-π-D-A dyes (DPP-1 ∼ 4). All dyes have been characterized with NMR, HRMS, UV-vis and fluorescence spectra, and taken into cyclic voltammetry measurements. The devices of new dyes have been determined by photoelectrochemical experiments (IV, IPCE and EIS), in which, solar cell of DPP-4 with biphenyl ring π-spacer enhances obviously its photoelectric conversion efficiency to 7.66% reaching 94% of N719-based standard cell and displays good long-term stability with quasi-solid-state electrolyte. Density functional theory (DFT) calculations of new dyes provide further insight into the molecular geometries and the impacts of the torsion angles on their photovoltaic performance. Large dihedral angles in DPP dyes induce good charge separation for efficient unidirectional flow of electron from donor to acceptor.

  7. Dye-sensitized solar cells based on ZnO nanorod arrays

    NASA Astrophysics Data System (ADS)

    Xie, Yu; Li, Shaoyan; Zhang, Ting; Joshi, Prakash; Fong, Hao; Ropp, Mike; Galipeau, David; Qiao, Qiquan

    2008-08-01

    A series of dye-sensitized solar cells (DSSCs) were fabricated using ZnO nanorod arrays as the anode electrode. The ZnO nanorod arrays were grown on the fluorine doped tin dioxide (FTO) substrates by a hydrothermal method. The scanning electron microscopy (SEM) images indicated that the ZnO nanorod arrays were highly oriented on FTO substrates with an average diameter of ~40 nm and an average length of ~1 μm. After sensitized by Z-907 dye via impregnation in solution, ZnO nanorod arrays changed the color from white to pink. This indicated that the dye had been successfully attached to ZnO nanorods. The high-aspect-ratio (~25) ZnO nanorod arrays are expected to improve charge transport through the formation of continuous channels along the nanorods. We fabricated photovoltaic cells based on these ZnO nanorod arrays and found the deposition time and effective area were two important factors affecting short circuit current densities and cell efficiencies. The device performance (Voc = 0.48 V, Jsc = 5.39 mA/cm2, η = 0.73 %) showed a great potential for solar energy conversion.

  8. Novel energy relay dyes for high efficiency dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Rahman, Md. Mahbubur; Ko, Min Jae; Lee, Jae-Joon

    2015-02-01

    4',6-Diamidino-2-phenylindole (DAPI) and Hoechst 33342 (H33342) were used as novel energy relay dyes (ERDs) for an efficient energy transfer to the N719 dye in I-/I3- based liquid-junction dye-sensitized solar cells (DSSCs). The introduction of the ERDs, either as an additive in the electrolyte or as a co-adsorbent, greatly enhanced the power conversion efficiencies (PCEs), mainly because of an increase in short-circuit current density (Jsc). This was attributed to the effects of non-radiative Förster-type excitation energy transfer as well as the radiative (emission)-type fluorescent energy transfer to the sensitizers. The net PCEs for the N719-sensitized DSSCs with DAPI and H33342 were 10.65% and 10.57%, and showed an improvement of 12.2% and 11.4% over control devices, respectively.4',6-Diamidino-2-phenylindole (DAPI) and Hoechst 33342 (H33342) were used as novel energy relay dyes (ERDs) for an efficient energy transfer to the N719 dye in I-/I3- based liquid-junction dye-sensitized solar cells (DSSCs). The introduction of the ERDs, either as an additive in the electrolyte or as a co-adsorbent, greatly enhanced the power conversion efficiencies (PCEs), mainly because of an increase in short-circuit current density (Jsc). This was attributed to the effects of non-radiative Förster-type excitation energy transfer as well as the radiative (emission)-type fluorescent energy transfer to the sensitizers. The net PCEs for the N719-sensitized DSSCs with DAPI and H33342 were 10.65% and 10.57%, and showed an improvement of 12.2% and 11.4% over control devices, respectively. Electronic supplementary information (ESI) available: Details of the materials and instrumentation, device fabrication, measurement and calculations of the quantum yield (Qd), calculations of the Förster radius (R0), optimization of the ERDs mixed with electrolyte according to Type-A strategy; normalized absorption profiles of the N3, Ru505, and Z907 dyes and the emission profiles of DAPI and H33342

  9. Metal-organic frameworks derived carbon as a high-efficiency counter electrode for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Sun, Xun; Li, Yafeng; Dou, Jie; Shen, Deli; Wei, Mingdeng

    2016-08-01

    Metal-organic frameworks, ZIF-8, derived carbon materials are firstly applied as a counter electrode of dye-sensitized solar cells due to their easy fabrication, large specific surface area and high catalytic activities towards the reduction of I3- ions. An efficiency of 7.32% is achieved under the illumination of 1 sun (AM 1.5, 100 mW/cm2), which is comparable to that of the solar cell based on Pt electrode.

  10. Dye-sensitized solar cell with energy storage function through PVDF/ZnO nanocomposite counter electrode.

    PubMed

    Zhang, Xi; Huang, Xuezhen; Li, Chensha; Jiang, Hongrui

    2013-08-14

    Dye-sensitized solar cells with an energy storage function are demonstrated by modifying its counter electrode with a poly (vinylidene fluoride)/ZnO nanowire array composite. This simplex device could still function as an ordinary solar cell with a steady photocurrent output even after being fully charged. An energy storage density of 2.14 C g(-1) is achieved, while simultaneously a 3.70% photo-to-electric conversion efficiency is maintained.

  11. Natural dye extracted from karkadah and its application in dye-sensitized solar cells: experimental and density functional theory study.

    PubMed

    Reda, S M; Soliman, K A

    2016-02-01

    This work presents an experimental and theoretical study of cyanidin natural dye as a sensitizer for ZnO dye-sensitized solar cells. ZnO nanoparticles were prepared using ammonia and oxalic acid as a capping agent. The calculated average size of the synthesized ZnO with different capping agents was found to be 32.1 nm. Electronic properties of cyanidin and delphinidin dye were studied using density functional theory (DFT) and time-dependent DFT with a B3LYP/6-31G(d,p) level. By comparing the theoretical results with the experimental data, the cyanidin dye can be used as a sensitizer in dye-sensitized solar cells. An efficiency of 0.006% under an AM-1.5 illumination at 100  mW/cm(2) was attained. The influence of dye adsorption time on the solar cell performance is discussed.

  12. A dye sensitized solar cell using natural counter electrode and natural dye derived from mangosteen peel waste

    NASA Astrophysics Data System (ADS)

    Maiaugree, Wasan; Lowpa, Seksan; Towannang, Madsakorn; Rutphonsan, Phikun; Tangtrakarn, Apishok; Pimanpang, Samuk; Maiaugree, Prapen; Ratchapolthavisin, Nattawat; Sang-Aroon, Wichien; Jarernboon, Wirat; Amornkitbamrung, Vittaya

    2015-10-01

    Mangosteen peel is an inedible portion of a fruit. We are interested in using these residues as components of a dye sensitized solar cell (DSSC). Carbonized mangosteen peel was used with mangosteen peel dye as a natural counter electrode and a natural photosensitizer, respectively. A distinctive mesoporous honeycomb-like carbon structure with a rough nanoscale surface was found in carbonized mangosteen peels. The efficiency of a dye sensitized solar cell using carbonized mangosteen peel was compared to that of DSSCs with Pt and PEDOT-PSS counter electrodes. The highest solar conversion efficiency (2.63%) was obtained when using carbonized mangosteen peel and an organic disulfide/thiolate (T2/T-) electrolyte.

  13. A dye sensitized solar cell using natural counter electrode and natural dye derived from mangosteen peel waste

    PubMed Central

    Maiaugree, Wasan; Lowpa, Seksan; Towannang, Madsakorn; Rutphonsan, Phikun; Tangtrakarn, Apishok; Pimanpang, Samuk; Maiaugree, Prapen; Ratchapolthavisin, Nattawat; Sang-aroon, Wichien; Jarernboon, Wirat; Amornkitbamrung, Vittaya

    2015-01-01

    Mangosteen peel is an inedible portion of a fruit. We are interested in using these residues as components of a dye sensitized solar cell (DSSC). Carbonized mangosteen peel was used with mangosteen peel dye as a natural counter electrode and a natural photosensitizer, respectively. A distinctive mesoporous honeycomb-like carbon structure with a rough nanoscale surface was found in carbonized mangosteen peels. The efficiency of a dye sensitized solar cell using carbonized mangosteen peel was compared to that of DSSCs with Pt and PEDOT-PSS counter electrodes. The highest solar conversion efficiency (2.63%) was obtained when using carbonized mangosteen peel and an organic disulfide/thiolate (T2/T−) electrolyte. PMID:26458745

  14. Natural dye extracted from karkadah and its application in dye-sensitized solar cells: experimental and density functional theory study.

    PubMed

    Reda, S M; Soliman, K A

    2016-02-01

    This work presents an experimental and theoretical study of cyanidin natural dye as a sensitizer for ZnO dye-sensitized solar cells. ZnO nanoparticles were prepared using ammonia and oxalic acid as a capping agent. The calculated average size of the synthesized ZnO with different capping agents was found to be 32.1 nm. Electronic properties of cyanidin and delphinidin dye were studied using density functional theory (DFT) and time-dependent DFT with a B3LYP/6-31G(d,p) level. By comparing the theoretical results with the experimental data, the cyanidin dye can be used as a sensitizer in dye-sensitized solar cells. An efficiency of 0.006% under an AM-1.5 illumination at 100  mW/cm(2) was attained. The influence of dye adsorption time on the solar cell performance is discussed. PMID:26836089

  15. Recent Advances of Cobalt(II/III) Redox Couples for Dye-Sensitized Solar Cell Applications.

    PubMed

    Giribabu, Lingamallu; Bolligarla, Ramababu; Panigrahi, Mallika

    2015-08-01

    In recent years dye-sensitized solar cells (DSSCs) have emerged as one of the alternatives for the global energy crisis. DSSCs have achieved a certified efficiency of >11% by using the I(-) /I3 (-) redox couple. In order to commercialize the technology almost all components of the device have to be improved. Among the various components of DSSCs, the redox couple that regenerates the oxidized sensitizer plays a crucial role in achieving high efficiency and durability of the cell. However, the I(-) /I3 (-) redox couple has certain limitations such as the absorption of triiodide up to 430 nm and the volatile nature of iodine, which also corrodes the silver-based current collectors. These limitations are obstructing the commercialization of this technology. For this reason, one has to identify alternative redox couples. In this regard, the Co(II/III) redox couple is found to be the best alternative to the existing I(-) /I3 (-) redox couple. Recently, DSSC test cell efficiency has risen up to 13% by using the cobalt redox couple. This review emphasizes the recent development of Co(II/III) redox couples for DSSC applications.

  16. Investigation the cause of plasma treatment for low temperature annealed dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Zen, Shungo; Komatsu, Yuta; Ono, Ryo

    2015-09-01

    Dye-sensitized solar cells (DSSCs) require annealing of TiO2photoelectrodes at 450 C to 550 C. However, such high-temperature annealing is unfavorable because it limits the use of materials that cannot withstand high temperatures, such as plastic substrates. In our previous paper, a low temperature annealing technique of TiO2 photoelectrodes using ultraviolet light and dielectric barrier discharge treatments was proposed to reduce the annealing temperature from 450 C to 150 C for a TiO2 paste containing an organic binder. Here, we investigated the cause of plasma treatment via the Nyquist diagram (Cole-Cole plot) of DSSCs. The Nyquist diagram was masured with a frequency response analyzer (NF Corporation, FRA5022) under 100 mW/cm2 illumination of a calibrated xenon lamp (Hamamatsu L2274, 150W). The lifetime of the electrons, the effective electron diffusion coefficient, and the electron diffusion length of TiO2 photoelectrodes were determined by analyzing the Nyquist diagrams. As a result of analyzing the Nyquist diagrams, it was shown that plasma treatment can reduce the electron transport resistance and promote the necking of Hot UV annealed TiO2 nanoparticles. This work was supported by Grant-in-Aid for JSPS Fellows.

  17. Two kinds of graphene-based composites for photoanode applying in dye-sensitized solar cell

    NASA Astrophysics Data System (ADS)

    Tang, Bo; Hu, Guoxin

    2012-12-01

    Two kinds of graphene modified TiO2 composites are synthesized by hydrothermal method and layer-by-layer self-assembly technology. Graphene/titanate nanotubes (GTNTs) films have great light-harvesting efficiencies, and the amount of graphene does not obviously influence their optical performance. Alternating graphene/TiO2 (prepared by supercritical treatment, GSCT) multilayer films possess superior electron transport ability, and the number of bi-layers plays as a central role for their electrical property. The outstanding light scattering and carrier transport properties of these promising films promote the performance of dye-sensitized solar cells (DSSCs). The power conversion efficiencies (η) of the DSSCs reach 6.46% and 7.54% under AM-1.5G by using GSCT-P25 (10 μm) and P25-GTNTs (15 μm) photoanodes, and the increases are 33.8% and 20.6% compared with that of by using a P25 photoanode with same thickness. The η reaches 8.67% when a preliminarily optimized GSCT-P25-GTNTs (15 μm) photoanode is adopted, which is far better than employing a pure P25 photoanode (6.25%).

  18. Performance and stability improvements for dye-sensitized solar cells in the presence of luminescent coatings

    NASA Astrophysics Data System (ADS)

    Bella, Federico; Griffini, Gianmarco; Gerosa, Matteo; Turri, Stefano; Bongiovanni, Roberta

    2015-06-01

    Here we present how the sunlight radiation incident on a dye-sensitized solar cell (DSSC) can be shifted of a few tens of nanometers by means of an economical, easy to prepare and multifunctional photocurable fluoropolymeric light-shifting (LS) coating, to achieve both improved efficiency and device stability. By the introduction of a very small amount of a luminescent agent in the LS coating, the down-shifting of near-UV photons to higher wavelengths easily harvestable by the organic dye of a DSSC is successfully demonstrated. This optical effect not only results in an over 60% improvement of the power conversion efficiency of DSSC devices, but the UV light filtering action promoted by the luminescent agent also provides protection to the photosensitive DSSC components. This aspect, combined with a potential thermal shielding effect and the easy-cleaning behavior imparted to the coating by its fluorinated nature, leads to excellent device stability as evidenced from an aging test performed outdoors under real operating conditions for more than 2000 h. Our study demonstrates that the use of light-cured multifunctional coatings with light management characteristics at the nanometer scale represents a new promising strategy to simultaneously increase the performance and durability of DSSC devices.

  19. Incorporation of graphene into SnO2 photoanodes for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Batmunkh, Munkhbayar; Dadkhah, Mahnaz; Shearer, Cameron J.; Biggs, Mark J.; Shapter, Joseph G.

    2016-11-01

    In dye-sensitized solar cell (DSSC) photoanodes, tin dioxide (SnO2) structures present a promising alternative semiconducting oxide to the conventional titania (TiO2), but they suffer from poor photovoltaic (PV) efficiency caused by insufficient dye adsorption and low energy value of the conduction band. A hybrid structure consisting of SnO2 and reduced graphene oxide (SnO2-RGO) was synthesized via a microwave-assisted method and has been employed as a photoanode in DSSCs. Incorporation of RGO into the SnO2 photoanode enhanced the power conversion efficiency of DSSC device by 91.5%, as compared to the device assembled without RGO. This efficiency improvement can be attributed to increased dye loading, enhanced electron transfer and addition of suitable energy levels in the photoanode. Finally, the use of RGO addresses the major shortcoming of SnO2 when employed as a DSSC photoanode, namely poor dye adsorption and slow electron transfer rate.

  20. Doped In₂O₃ inverse opals as photoanode for dye sensitized solar cells.

    PubMed

    Kong, Lingxin; Dai, Qilin; Miao, Chuang; Xu, Lin; Song, Hongwei

    2015-07-15

    One promising way to improve the power conversion efficiency (PCE) of dye-sensitized solar cells (DSSCs), which have attracted great interest due to their low cost, is modifying the working electrode. In this work, Tm and Yb doped as well as undoped In2O3 inverse opals (IOs) were synthesized by the sol-gel method. DSSCs based on In2O3, In2O3:Tm and In2O3:Yb IOs as photoanodes were fabricated and studied. It is observed that the device performance including open-circuit voltage (V(oc)) and short-circuit current (J(sc)) increased largely with the increasing pore size of the IOs and the introduction of Tm and Yb elements in the In2O3 lattices. The PCE of the DSSC was increased from 0.33% to 0.96% when the ln2O3 IOs photoanode was substituted by ln2O3:Yb IOs. The electrochemical impedance spectroscopy (EIS) measurements indicate that the modification of band gap in the Tm and Yb doped In2O3 IOs is significant for the improved performance, which can effectively suppress the charge transfer recombination and improve the electron lifetime. PMID:25823724

  1. The Role of Confined Water in Ionic Liquid Electrolytes for Dye-Sensitized Solar Cells.

    PubMed

    Jeon, Jiwon; Kim, Hyungjun; Goddard, William A; Pascal, Tod A; Lee, Ga-In; Kang, Jeung Ku

    2012-02-16

    Ionic liquids (ILs) provide an attractive medium for various chemical and redox reactions, where they are generally regarded as hydrophobic. However, Seddon et al. discovered that 4-10 wt % water absorbs into ILs that contain bulky anions, and Cammarata et al. found that the molecular state of water in ILs is dramatically different from that of bulk liquid water or that of water vapor. To determine the microstructure of water incorporated into ILs and the impact on properties, we carried out first-principles-based molecular dynamics simulations. We find water in three distinct phases depending on water content, and that the transport properties depend on the nature of the water phases. These results suggest that the optimal water content is ∼10% mole fraction of water molecules (∼1.1 wt %) for applications such as nonvolatile electrolytes for dye-sensitized solar cells (DSSCs). This suggests a strategy for improving the performance of IL DSSC by replacing water with additives that would play the same role as water (since too much water can deteriorate performance at the anode-dye interface).

  2. Organic sensitizers for dye-sensitized solar cell (DSSC): Properties from computation, progress and future perspectives

    NASA Astrophysics Data System (ADS)

    Obotowo, I. N.; Obot, I. B.; Ekpe, U. J.

    2016-10-01

    The advent of the dye-sensitized solar cells (DSSCs) came at a time when the quest for alternative energy was high, replacing p-n junction photovoltaic devices. Its uniqueness arises from the fact that unlike the conventional systems where the semiconductor assumes the task of light absorption and charge transport, the two functions are separated in DSSC. Organic sensitizers have been used to harvest a large fraction of sunlight ranging from the UV region to the near infrared region of the spectrum leading to power conversion efficiencies of up to ∼ 10.65 % for metal-free organic sensitizers. Currently, experimental analysis of photo sensitizers utilized in DSSCs is often a trial and error process, often laborious and require extensive and expensive chemical synthesis. In most cases, disappointing results from late-stage of the dye synthesis indicate an urgent need to understand the properties of the dyes at a molecular level, before experiments take place. Fortunately, the use of quantum chemical calculations especially Density Functional Theory (DFT) to screen potential dyes has helped in developing efficient sensitizers and to reduce cost. In the present review article, we discuss the current state of the field, new concepts, design strategies, challenges facing the theoretical design and development of organic sensitizers for DSSCs and future perspectives.

  3. Extension lifetime for dye-sensitized solar cells through multiple dye adsorption/desorption process

    NASA Astrophysics Data System (ADS)

    Chiang, Yi-Fang; Chen, Ruei-Tang; Shen, Po-Shen; Chen, Peter; Guo, Tzung-Fang

    2013-03-01

    In this study, we propose a novel concept of extending the lifetime of dye-sensitized solar cells (DSCs) and reducing the costs of re-conditioning DSCs by recycling the FTO/TiO2 substrates. The photovoltaic performances of DSCs using substrates with various cycles of dye uptake and rinse off history are tested. The results show that dye adsorption and Voc are significantly increased under multiple dye adsorption/desorption process and resulted in the improvement of power conversion efficiency. Moreover, the dyeing kinetics is faster after multiple recycling processes, which is favorable for the industrial application. With surface analysis and charge transport characteristics, we also demonstrate the optimal functionality of TiO2/dye interface for the improved Voc and efficiency. The results confirm that the improved performances are due to increased dye loading and dense packing of dye molecules. Our results are beneficial for the understanding on the extension of DSCs lifetime after long-term operation in the application of DSC modules. This approach may also be applied in the replacement of newly synthesized photosensitizes to the active cells.

  4. Hyperbranched quasi-1D nanostructures for solid-state dye-sensitized solar cells.

    PubMed

    Passoni, Luca; Ghods, Farbod; Docampo, Pablo; Abrusci, Agnese; Martí-Rujas, Javier; Ghidelli, Matteo; Divitini, Giorgio; Ducati, Caterina; Binda, Maddalena; Guarnera, Simone; Li Bassi, Andrea; Casari, Carlo Spartaco; Snaith, Henry J; Petrozza, Annamaria; Di Fonzo, Fabio

    2013-11-26

    In this work we demonstrate hyperbranched nanostructures, grown by pulsed laser deposition, composed of one-dimensional anatase single crystals assembled in arrays of high aspect ratio hierarchical mesostructures. The proposed growth mechanism relies on a two-step process: self-assembly from the gas phase of amorphous TiO2 clusters in a forest of tree-shaped hierarchical mesostructures with high aspect ratio; oriented crystallization of the branches upon thermal treatment. Structural and morphological characteristics can be optimized to achieve both high specific surface area for optimal dye uptake and broadband light scattering thanks to the microscopic feature size. Solid-state dye sensitized solar cells fabricated with arrays of hyperbranched TiO2 nanostructures on FTO-glass sensitized with D102 dye showed a significant 66% increase in efficiency with respect to a reference mesoporous photoanode and reached a maximum efficiency of 3.96% (among the highest reported for this system). This result was achieved mainly thanks to an increase in photogenerated current directly resulting from improved light harvesting efficiency of the hierarchical photoanode. The proposed photoanode overcomes typical limitations of 1D TiO2 nanostructures applied to ss-DSC and emerges as a promising foundation for next-generation high-efficiency solid-state devices comprosed of dyes, polymers, or quantum dots as sensitizers.

  5. Highly Efficient Plastic Crystal Ionic Conductors for Solid-state Dye-sensitized Solar Cells

    NASA Astrophysics Data System (ADS)

    Hwang, Daesub; Kim, Dong Young; Jo, Seong Mu; Armel, Vanessa; Macfarlane, Douglas R.; Kim, Dongho; Jang, Sung-Yeon

    2013-12-01

    We have developed highly efficient, ambient temperature, solid-state ionic conductors (SSICs) for dye-sensitized solar cells (DSSCs) by doping a molecular plastic crystal, succinonitrile (SN), with trialkyl-substituted imidazolium iodide salts. High performance SSICs with enhanced ionic conductivity (2-4 mScm-1) were obtained. High performance solid-state DSSCs with power conversion efficiency of 7.8% were fabricated using our SSICs combined with unique hierarchically nanostructured TiO2 sphere (TiO2-SP) photoelectrodes; these electrodes have significant macroporosity, which assists penetration of the solid electrolyte into the electrode. The performance of our solid-state DSSCs is, to the best of our knowledge, the highest reported thus far for cells using plastic crystal-based SSICs, and is comparable to that of the state-of-the-art DSSCs which use ionic liquid type electrolytes. This report provides a logical strategy for the development of efficient plastic crystal-based SSICs for DSSCs and other electrochemical devices.

  6. Effects of Ethyl Cellulose on Performance of Titania Photoanode for Dye-sensitized Solar Cells

    NASA Astrophysics Data System (ADS)

    Liu, Ting-Chien; Wu, Chih-Chung; Huang, Chih-Hsiang; Chen, Chih-Ming

    2016-06-01

    Ethyl cellulose (EC) was added to a titania (TiO2) paste from 2 wt.% to 18 wt.% as a binder/dispersant, and its effects on the photovoltaic performance of dye-sensitized solar cells (DSSCs) were investigated. The TiO2 mesoporous film constructed on the photoanode exhibited a dense and network structure composed of well-interconnected TiO2 nanoparticles when using a proper amount of EC (10 wt.%). Excessive and deficient addition of EC resulted in aggregation of TiO2 nanoparticles and formation of pores, respectively, in the TiO2 film. The power conversion efficiency (PCE) of DSSC showed a strong dependence on the EC content and the highest PCE of 7.53% with the highest short-circuit current density (J SC) of 12.7 mA/cm2 was achieved when the content of EC was 10 wt.%. The incident photon-to-current conversion efficiency (IPCE) results indicated that the TiO2 mesoporous film fabricated using a proper EC addition was beneficial for electron generation (also confirmed by dye desorption experiments) and electron transport, and, therefore, improved the photovoltaic performance of DSSCs.

  7. Time-dependent efficiency measurements of donor-acceptor, dye-sensitized polymer solar cells

    NASA Astrophysics Data System (ADS)

    Bandaccari, Kyle; Chesmore, Grace; Tajalli-Tehrani Valverde, Parisa; Bugaj, Mitchel; McNelis, Brian; Barber, Richard, Jr.

    The fullerene/polymer active layer pairing of PCBM/P3HT has become the model system within the field of polymer solar cell research. A large body of work concerned with reporting improved efficiencies for this system exists, but truly quantitative studies of device lifetime and long-term degradation tendencies are much rarer. Here, we report the effects of two donor-acceptor diazo dye sensitizers on efficiency and lifetime upon addition into the PCBM/P3HT active layer at varied concentrations. The electrical and efficiency measurements were supplemented by time-dependent UV-visible spectroscopy studies and morphology investigations via atomic-force microscopy (AFM). This pairing with spectroscopy offers an internal check on the data as the rate of change in absorbance of the active layer correlates almost exactly to the rate of power conversion efficiency decrease. Additionally, AFM imaging reveals different morphology patterns when dye concentrations and functionalities change. Such observations suggest that such small-molecule sensitizers exert yet undetermined effects on the organization of components within the active layer at the molecular level.

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

    NASA Astrophysics Data System (ADS)

    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. N2 sorption analysis revealed high surface areas (203 m2 g-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 (VOC) of 0.74 V, short-circuit current density (JSC) of 3.83 mA cm-2 and an overall power conversion efficiency of 1.12% has been achieved.

  9. Improving Light Harvesting in Dye-Sensitized Solar Cells Using Hybrid Bimetallic Nanostructures

    DOE PAGES

    Zarick, Holly F.; Erwin, William R.; Boulesbaa, Abdelaziz; Hurd, Olivia K.; Webb, Joseph A.; Puretzky, Alexander A.; Geohegan, David B.; Bardhan, Rizia

    2016-01-25

    In this paper, we demonstrate improved light trapping in dye-sensitized solar cells (DSSCs) with hybrid bimetallic gold core/silver shell nanostructures. Silica-coated bimetallic nanostructures (Au/Ag/SiO2 NSs) integrated in the active layer of DSSCs resulted in 7.51% power conversion efficiency relative to 5.97% for reference DSSCs, giving rise to 26% enhancement in device performance. DSSC efficiencies were governed by the particle density of Au/Ag/SiO2 NSs with best performing devices utilizing only 0.44 wt % of nanostructures. We performed transient absorption spectroscopy of DSSCs with variable concentrations of Au/Ag/SiO2 NSs and observed an increase in amplitude and decrease in lifetime with increasing particlemore » density relative to reference. Finally, we attributed this trend to plasmon resonant energy transfer and population of the singlet excited states of the sensitizer molecules at the optimum concentration of NSs promoting enhanced exciton generation and rapid charge transfer into TiO2.« less

  10. Molecular modification of coumarin dyes for more efficient dye sensitized solar cells

    SciTech Connect

    Sanchez-de-Armas, Rocio; San-Miguel, Miguel A.; Oviedo, Jaime; Sanz, Javier Fdez.

    2012-05-21

    In this work, new coumarin based dyes for dye sensitized solar cells (DSSC) have been designed by introducing several substituent groups in different positions of the NKX-2311 structure. Two types of substitutions have been considered: the introduction of three electron-donating groups (-OH, -NH{sub 2}, and -OCH{sub 3}) and two different substituents with steric effect: -CH{sub 2}-CH{sub 2}-CH{sub 2}- and -CH{sub 2}-HC=CH-. The electronic absorption spectra (position and width of the first band and absorption threshold) and the position of the LUMO level related to the conduction band have been used as theoretical criteria to evaluate the efficiency of the new dyes. The introduction of a -NH{sub 2} group produces a redshift of the absorption maximum position and the absorption threshold, which could improve the cell efficiency. In contrast, the introduction of -CH{sub 2}-CH{sub 2}-CH{sub 2}- does not modify significantly the electronic structure of NKX-2311, but it might prevent aggregation. Finally, -CH{sub 2}-HC=CH- produces important changes both in the electronic spectrum and in the electronic structure of the dye, and it would be expected as an improvement of cell efficiency for these dyes.

  11. Optimization of the dye-sensitized solar cell performance by mechanical compression

    PubMed Central

    2014-01-01

    In this study, the P25 titanium dioxide (TiO2) nanoparticle (NP) thin film was coated on the fluorine-doped tin oxide (FTO) glass substrate by a doctor blade method. The film then compressed mechanically to be the photoanode of dye-sensitized solar cells (DSSCs). Various compression pressures on TiO2 NP film were tested to optimize the performance of DSSCs. The mechanical compression reduces TiO2 inter-particle distance improving the electron transport efficiency. The UV–vis spectrophotometer and electrochemical impedance spectroscopy (EIS) were employed to quantify the light-harvesting efficiency and the charge transport impedance at various interfaces in DSSC, respectively. The incident photon-to-current conversion efficiency was also monitored. The results show that when the DSSC fabricated by the TiO2 NP thin film compressed at pressure of 279 kg/cm2, the minimum resistance of 9.38 Ω at dye/TiO2 NP/electrolyte interfaces, the maximum short-circuit photocurrent density of 15.11 mA/cm2, and the photoelectric conversion efficiency of 5.94% were observed. Compared to the DSSC fabricated by the non-compression of TiO2 NP thin film, the overall conversion efficiency is improved over 19.5%. The study proves that under suitable compression pressure the performance of DSSC can be optimized. PMID:25276109

  12. The influence of magnesium oxide interfacial layer on photovoltaic properties of dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Asemi, M.; Ghanaatshoar, M.

    2016-09-01

    In the present study, to enhance the power conversion efficiency of the DSSCs, we introduce MgO insulating layers at the interface between TiO2 and electrolyte to decrease charge recombination rate by suppressing the electron transfer from TiO2 to the electrolyte. The thickness of the MgO layer plays a vital role in the kinetics of dye-sensitized solar cells and affects their overall efficiency. The cell with optimized thickness of MgO layer exhibits the highest conversion efficiency ( η = 5.12 %) with a high short-circuit current density (18.15 mA/cm2) and open-circuit voltage (0.571 V). Open-circuit voltage decay measurement results verify the improvement of the electrons lifetime in the DSSCs fabricated with surface-modified photoanodes due to the retarding the charge recombination. In order to explore the reasons for the J SC improvement, incident photon-to-current conversion efficiency measurement was taken. Our results show that the enhancement in the photoinjected electron lifetime can contribute to an increase in the electron collection efficiency, leading to the improved J SC value. Furthermore, the enhancement in the photoinjected electron recombination rate is also demonstrated by electrochemical impedance spectroscopy.

  13. Recovery of dye-sensitized solar cell's performance by heat treatment.

    PubMed

    Berginc, Marko; Topič, Marko; Opara Krašovec, Urša

    2014-07-01

    The formation of iodine containing crystals with ageing in ionic liquid based dye-sensitized solar cells (DSSCs) containing an I3(-)/I(-) redox couple has already been confirmed. In this report we show how the size of these crystals can reversibly change during operation and the effects this has on cell performance. We also show how heat treatment and applied forward and reverse current treatment influence crystal growth in the cell. Crystal growth was tracked using electroluminescence and transmittance imaging, while current-voltage characterization and electrical impedance spectroscopy were used to measure cell performance and follow the changes in I3(-) diffusion, charge transfer resistance, and recombinations occurring in the DSSCs. Results reveal that applying a reverse current to the DSSC leads to the rapid formation of H2 bubbles while crystals grow rapidly when a forward current is applied. Additionally heat treatment at 80 °C can completely recover performance of a degraded cell showing visible defects and a large inhomogeneous active area.

  14. Efficient synthesis of triarylamine-based dyes for p-type dye-sensitized solar cells.

    PubMed

    Wild, Martin; Griebel, Jan; Hajduk, Anna; Friedrich, Dirk; Stark, Annegret; Abel, Bernd; Siefermann, Katrin R

    2016-01-01

    The class of triarylamine-based dyes has proven great potential as efficient light absorbers in inverse (p-type) dye sensitized solar cells (DSSCs). However, detailed investigation and further improvement of p-type DSSCs is strongly hindered by the fact that available synthesis routes of triarylamine-based dyes are inefficient and particularly demanding with regard to time and costs. Here, we report on an efficient synthesis strategy for triarylamine-based dyes for p-type DSSCs. A protocol for the synthesis of the dye-precursor (4-(bis(4-bromophenyl)amino)benzoic acid) is presented along with its X-ray crystal structure. The dye precursor is obtained from the commercially available 4(diphenylamino)benzaldehyde in a yield of 87% and serves as a starting point for the synthesis of various triarylamine-based dyes. Starting from the precursor we further describe a synthesis protocol for the dye 4-{bis[4'-(2,2-dicyanovinyl)-[1,1'-biphenyl]-4-yl]amino}benzoic acid (also known as dye P4) in a yield of 74%. All synthesis steps are characterized by high yields and high purities without the need for laborious purification steps and thus fulfill essential requirements for scale-up. PMID:27196877

  15. Theoretical investigation of triphenylamine dye/titanium dioxide interface for dye-sensitized solar cells.

    PubMed

    Fan, Wenjie; Tan, Dazhi; Deng, Weiqiao

    2011-09-28

    The structural, electronic and optical features of two metal-free triphenylamine (TPA) organic dyes (namely C206 and C217) before and after binding to a TiO(2) anatase nanoparticle have been investigated in detail, as a model for the corresponding dye-sensitized solar cells (DSSCs). The combination of density functional tight-binding (DFTB), density functional theory (DFT), and time-dependent DFT (TDDFT) approaches are employed. To understand the effects of the linker part in the TPA organic dyes on the energy conversion efficiency of the DSSCs, C217 and C206, which share the same donor and anchor parts but different linker parts, are theoretically evaluated. Our results show that compared with C206 containing just one thienothiophene unit as the linker, for C217 the introduction of one electron-rich 3,4-ethylenedioxythiophene group to the linker part results in stronger couplings with the TiO(2) conduction band and more efficient electron transfer. This difference contributes to the higher efficiency of C217 in DSSCs experiments. This study is expected to assist the molecular design of new and more efficient TPA-based organic dyes for the optimization of the DSSCs.

  16. Charge recombination mechanism to explain the negative capacitance in dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Lie-Feng, Feng; Kun, Zhao; Hai-Tao, Dai; Shu-Guo, Wang; Xiao-Wei, Sun

    2016-03-01

    Negative capacitance (NC) in dye-sensitized solar cells (DSCs) has been confirmed experimentally. In this work, the recombination behavior of carriers in DSC with semiconductor interface as a carrier’s transport layer is explored theoretically in detail. Analytical results indicate that the recombination behavior of carriers could contribute to the NC of DSCs under small signal perturbation. Using this recombination capacitance we propose a novel equivalent circuit to completely explain the negative terminal capacitance. Further analysis based on the recombination complex impedance show that the NC is inversely proportional to frequency. In addition, analytical recombination resistance is composed by the alternating current (AC) recombination resistance (Rrac) and the direct current (DC) recombination resistance (Rrdc), which are caused by small-signal perturbation and the DC bias voltage, respectively. Both of two parts will decrease with increasing bias voltage. Project supported by the National Natural Science Foundation of China (Grant Nos. 11204209 and 60876035) and the Natural Science Foundation of Tianjin City, China (Grant No. 13JCZDJC32800).

  17. The role of printing techniques for large-area dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Mariani, Paolo; Vesce, Luigi; Di Carlo, Aldo

    2015-10-01

    The versatility of printing technologies and their intrinsic ability to outperform other techniques in large-area deposition gives scope to revolutionize the photovoltaic (PV) manufacturing field. Printing methods are commonly used in conventional silicon-based PVs to cover part of the production process. Screen printing techniques, for example, are applied to deposit electrical contacts on the silicon wafer. However, it is with the advent of third generation PVs that printing/coating techniques have been extensively used in almost all of the manufacturing processes. Among all the third generation PVs, dye sensitized solar cell (DSSC) technology has been developed up to commercialization levels. DSSCs and modules can be fabricated by adopting all of the main printing techniques on both rigid and flexible substrates. This allows an easy tuning of cell/module characteristics to the desired application. Transparency, colour, shape, layout and other DSSC’s features can be easily varied by changing the printing parameters and paste/ink formulations used in the printing process. This review focuses on large-area printing/coating technologies for the fabrication of DSSCs devices. The most used and promising techniques are presented underlining the process parameters and applications.

  18. Microfluidic housing system: a useful tool for the analysis of dye-sensitized solar cell components

    NASA Astrophysics Data System (ADS)

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

    2012-11-01

    In order to understand the behavior of the different dye-sensitized solar cell (DSC) components, an in-situ analysis should give fundamental help but it is impossible to be performed without compromising the integrity of the cell. Our recently proposed novel microfluidic approach for the fabrication of DSCs is based on a reversible sealing of the two transparent electrodes and it allows the easy assembling and disassembling of the cell, making possible an analysis of the components over time. The aim of this work is not to investigate the different degradation mechanisms of a standard DSC: we want to show that, by using a microfluidic architecture, it is possible to perform a non-destructive analysis and to monitor the photoanode and the counter electrode properties during their lifetime. Morphological (field emission scanning electron microscopy), wetting (contact angle), optical (UV-visible spectroscopy) and electrical (current-voltage and electrochemical impedance spectroscopy measurements under standard AM1.5G illumination) characterizations have been performed over a period of three weeks. The results show how the variation of the wetting and morphological properties at the counter electrode and of the dye absorbance at the photoanode are strongly related to the decrease of the cell performances as evidenced by electrical characterization, thus demonstrating the effectiveness of the use of our structure in this kind of studies.

  19. Degradation of cyanoacrylic acid-based organic sensitizers in dye-sensitized solar cells.

    PubMed

    Chen, Cheng; Yang, Xichuan; Cheng, Ming; Zhang, Fuguo; Sun, Licheng

    2013-07-01

    Organic dyes have become widely used in dye-sensitized solar cells (DSSCs) because of their good performance, flexible structural modifications, and low costs. To increase the photostability of organic dye-based DSSCs, we conducted a full study on the degradation mechanism of cyanoacrylic acid-based organic sensitizers in DSSCs. The results showed that with the synergy between water and UV light, the sensitizer could desorb from the TiO2 surface and the cyanoacrylic acid unit of the sensitizer was transformed into the aldehyde group. It was also observed that the water content had a great effect on the degradation process. Our experiments conducted using (18) O-labeled water demonstrated that the oxygen atom of the aldehyde group identified in the degraded dye came from the solvent water in the DSSCs. Therefore, controlling the water content during DSSC fabrication, good sealing of cells, and filtering the UV light are crucial to produce DSSCs that are more durable and robust.

  20. Spherical TiO2 aggregates with different building units for dye-sensitized solar cells.

    PubMed

    Liu, Zhaohui; Su, Xunjia; Hou, Genliang; Bi, Song; Xiao, Zhou; Jia, Haipeng

    2013-09-01

    Tailoring the architectures of spherical TiO2 aggregates is crucial to obtain superior photovoltaic properties and promote their application in dye-sensitized solar cells (DSSCs). Herein, we synthesized spherical TiO2 aggregates using different building units, including nanocrystallites, nanorods, nanosheets, and nanotubes, via a hydrothermal method, and studied the effect of the building units on the performances of DSSCs. The aggregates assembled by uniform nanosheet and nanotube building units were synthesized with the use of spherical TiO2 nanorod aggregates as titanium sources in an alkaline hydrothermal reaction. Compared with TiO2 nanoparticles, the spherical TiO2 aggregates possess higher surface area, more efficient light scattering ability, and better electron transport properties. Among the four types of spherical TiO2 aggregates; the nanorod, nanotube, and nanosheet aggregates demonstrate better electron transport properties than the nanocrystallite aggregates; the nanotube and nanosheet aggregates exhibit more efficient light scattering than the nanocrystallite and nanorod aggregates; and the nanotube aggregates show the highest surface area. Thus the DSSC based on nanotube aggregates exhibited the highest energy conversion efficiency of 7.48%, which is 16.0%, 9.7%, and 19.5% higher than those of the DSSCs based on the nanosheet, nanorod, and nanocrystallite aggregates, respectively.

  1. A hybrid electron donor comprising cyclopentadithiophene and dithiafulvenyl for dye-sensitized solar cells

    PubMed Central

    Sorohhov, Gleb; Yi, Chenyi; Grätzel, Michael; Decurtins, Silvio

    2015-01-01

    Summary Two new photosensitizers featured with a cyanoacrylic acid electron acceptor (A) and a hybrid electron donor (D) of cyclopentadithiophene and dithiafulvenyl, either directly linked or separated by a phenyl ring, were synthesized and characterized. Both of them undergo two reversible oxidations and strongly absorb in the visible spectral region due to a photo-induced intramolecular charge-transfer (ICT) transition. To a great extent, the electronic interaction between the D and A units is affected by the presence of a phenyl spacer. Without a phenyl ring, the D unit appears more difficult to oxidize due to a strong electron-withdrawing effect of the A moiety. In sharp contrast, the insertion of the phenyl ring between the D and A units leads to a broken π-conjugation and therefore, the oxidation potentials remain almost unchanged compared to those of an analogue without the A group, suggesting that the electronic coupling between D and A units is relatively weak. As a consequence, the lowest-energy absorption band shows a slight hypsochromic shift upon the addition of the phenyl spacer, indicative of an increased HOMO–LUMO gap. In turn, the direct linkage of D and A units leads to an effective π-conjugation, thus substantially lowering the HOMO–LUMO gap. Moreover, the application in dye-sensitized solar cells was investigated, showing that the power conversion efficiency increases by the insertion of the phenyl unit. PMID:26199660

  2. Efficient synthesis of triarylamine-based dyes for p-type dye-sensitized solar cells

    PubMed Central

    Wild, Martin; Griebel, Jan; Hajduk, Anna; Friedrich, Dirk; Stark, Annegret; Abel, Bernd; Siefermann, Katrin R.

    2016-01-01

    The class of triarylamine-based dyes has proven great potential as efficient light absorbers in inverse (p-type) dye sensitized solar cells (DSSCs). However, detailed investigation and further improvement of p-type DSSCs is strongly hindered by the fact that available synthesis routes of triarylamine-based dyes are inefficient and particularly demanding with regard to time and costs. Here, we report on an efficient synthesis strategy for triarylamine-based dyes for p-type DSSCs. A protocol for the synthesis of the dye-precursor (4-(bis(4-bromophenyl)amino)benzoic acid) is presented along with its X-ray crystal structure. The dye precursor is obtained from the commercially available 4(diphenylamino)benzaldehyde in a yield of 87% and serves as a starting point for the synthesis of various triarylamine-based dyes. Starting from the precursor we further describe a synthesis protocol for the dye 4-{bis[4′-(2,2-dicyanovinyl)-[1,1′-biphenyl]-4-yl]amino}benzoic acid (also known as dye P4) in a yield of 74%. All synthesis steps are characterized by high yields and high purities without the need for laborious purification steps and thus fulfill essential requirements for scale-up. PMID:27196877

  3. Realizing omnidirectional light harvesting by employing hierarchical architecture for dye sensitized solar cells.

    PubMed

    Hsieh, Ming-Yang; Lai, Fang-I; Chen, Wei-Chun; Hsieh, Min-Chi; Hu, Hsiang-Yi; Yu, Peichen; Kuo, Hao-Chung; Kuo, Shou-Yi

    2016-03-14

    To improve the omnidirectional light-harvesting in dye-sensitized solar cells (DSSCs), here we present a dandelion-like structure composed of ZnO hemispherical shells and nanorods. Uniformly distributed hemispherical shells effectively suppress the reflection over the broadband region at incident angles up to 60°, greatly improving the optical absorption of the DSSCs. In addition, modulating the length of the ZnO nanorods controls the omnidirectional characteristics of DSSCs. This phenomenon is attributed to the degree of periodicity of the ZnO dandelion-like structures. Cells with shorter rods exhibit a high degree of periodicity, thus the conversion efficiencies of the cells show specific angle-independent features. On the other hand, the cells with longer lengths reveal angle-dependent photovoltaic performance. Along with the simulation, the cells with dandelion-like ZnO structures can couple incident photons efficiently to achieve excellent broadband and omnidirectional light-harvesting performances experimentally, and the DSSCs enhanced the conversion efficiency by 48% at large incident angles. All these findings not only provide further insight into the light-trapping mechanism in these complex three-dimensional nanostructures but also offer efficient omnidirectional and broadband nanostructured photovoltaics for advanced applications. PMID:26899775

  4. Near Field Enhanced Photocurrent Generation in P-type Dye-Sensitized Solar Cells

    PubMed Central

    Xu, Xiaobao; Cui, Jin; Han, Junbo; Zhang, Junpei; Zhang, Yibo; Luan, Lin; Alemu, Getachew; Wang, Zhong; Shen, Yan; Xiong, Dehua; Chen, Wei; Wei, Zhanhua; Yang, Shihe; Hu, Bin; Cheng, Yibing; Wang, Mingkui

    2014-01-01

    Over the past few decades, the field of p-type dye-sensitized solar cell (p-DSSC) devices has undergone tremendous advances, in which Cu-based delafossite nanocrystal is of prime interest. This paper presents an augment of about 87% improvement in photocurrent observed in a particular configuration of organic dye P1 sensitized CuCrO2 delafossite nanocrystal electrode coupled with organic redox shuttle, 1-methy-1H- tetrazole-5-thiolate and its disulfide dimer when Au nanoparticles (NPs, with diameter of about 20 nm) is added into the photocathode, achieving a power convert efficiency of 0.31% (measured under standard AM 1.5 G test conditions). Detailed investigation shows that the local electrical-magnetic field effect, induced by Au NPs among the mesoporous CuCrO2 film, can improve the charge injection efficiency at dye/semiconductor interface, which is responsible for the bulk of the gain in photocurrent. PMID:24492539

  5. Energy Storage via Polyvinylidene Fluoride Dielectric on the Counterelectrode of Dye-Sensitized Solar Cells.

    PubMed

    Huang, Xuezhen; Zhang, Xi; Jiang, Hongrui

    2014-02-15

    To study the fundamental energy storage mechanism of photovoltaically self-charging cells (PSCs) without involving light-responsive semiconductor materials such as Si powder and ZnO nanowires, we fabricate a two-electrode PSC with the dual functions of photocurrent output and energy storage by introducing a PVDF film dielectric on the counterelectrode of a dye-sensitized solar cell. A layer of ultrathin Au film used as a quasi-electrode establishes a shared interface for the I(-)/I3(-) redox reaction and for the contact between the electrolyte and the dielectric for the energy storage, and prohibits recombination during the discharging period because of its discontinuity. PSCs with a 10-nm-thick PVDF provide a steady photocurrent output and achieve a light-to-electricity conversion efficiency (η) of 3.38%, and simultaneously offer energy storage with a charge density of 1.67 C g(-1). Using this quasi-electrode design, optimized energy storage structures may be used in PSCs for high energy storage density.

  6. Single-wire dye-sensitized solar cells wrapped by carbon nanotube film electrodes.

    PubMed

    Zhang, Sen; Ji, Chunyan; Bian, Zhuqiang; Liu, Runhua; Xia, Xinyuan; Yun, Daqin; Zhang, Luhui; Huang, Chunhui; Cao, Anyuan

    2011-08-10

    Conventional fiber-shaped polymeric or dye-sensitized solar cells (DSSCs) are usually made into a double-wire structure, in which a secondary electrode wire (e.g., Pt) was twisted along the primary core wire consisting of active layers. Here, we report highly flexible DSSCs based on a single wire, by wrapping a carbon nanotube film around Ti wire-supported TiO(2) tube arrays as the transparent electrode. Unlike a twisted Pt electrode, the CNT film ensures full contact with the underlying active layer, as well as uniform illumination along circumference through the entire DSSC. The single-wire DSSC shows a power conversion efficiency of 1.6% under standard illumination (AM 1.5, 100 mW/cm(2)), which is further improved to more than 2.6% assisted by a second conventional metal wire (Ag or Cu). Our DSSC wires are stable and can be bent to large angles up to 90° reversibly without performance degradation. PMID:21766836

  7. Full-ionic liquid gel electrolytes: Enhanced photovoltaic performances in dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Li, Qinghua; Tang, Qunwei; He, Benlin; Yang, Peizhi

    2014-10-01

    Liquid electrolytes containing redox species have been widely used in dye-sensitized solar cells (DSSCs), whereas the volatility of organic solvents has been a tremendous obstacle for their commercial application. To assemble durable DSSCs, here we report the synthesis of full-ionic liquid electrolyte, in which 1-butyl-3-methylimidazolium nitrate is employed as solvent and 1-methyl-3-propylimidazolium iodide is iodide source. Using the imbibition performance of amphiphilic poly(acrylic acid/gelatin) [poly(AA/GR)] and poly(acrylic acid/cetyltrimethyl ammonium bromide) [poly(AA/CTAB)] matrices, full-ionic liquid electrolytes are imbibed into three-dimensional framework of poly(AA/GR) or poly(AA/CTAB) to form stable gel electrolytes. Room-temperature ionic conductivities as high as 17.82 and 18.44 mS cm-1 are recorded from full-ionic liquid imbibed poly(AA/GR) and poly(AA/CTAB) gel electrolytes, respectively. Promising power conversion efficiencies of 7.19% and 7.15% are determined from their DSSC devices in comparison with 6.55% and 6.12% from traditional acetonitrile-based poly(AA/GR) and poly(AA/CTAB) gel electrolytes, respectively. The new concept along with easy fabrication demonstrates the full-ionic liquid electrolytes to be good alternatives for robust gel electrolytes in quasi-solid-state DSSCs.

  8. Light collection optimization for composite photoanode in dye-sensitized solar cells: Towards higher efficiency

    SciTech Connect

    Guo, X. Z.; Shen, W. Z.

    2015-06-14

    Composite photoanode comprising nanoparticles and one-dimensional (1D) nanostructure is a promising alternative to conventional photoanode for dye-sensitized solar cells (DSCs). Besides fast electron transport channels, the 1D nanostructure also plays as light scattering centers. Here, we theoretically investigate the light scattering properties of capsule-shaped 1D nanostructure and their influence on the light collection of DSCs. It is found that the far-field light scattering of a single capsule depends on its volume, shape, and orientation: capsules with bigger equivalent spherical diameter, smaller aspect ratio, and horizontal orientation demonstrate stronger light scattering especially at large scattering angle. Using Monte Carlo approach, we simulated and optimized the light harvesting efficiency of the cell. Two multilayer composite photoanodes containing orderly or randomly oriented capsules are proposed. DSCs composed of these two photoanodes are promising for higher efficiencies because of their efficient light collection and superior electron collection. These results will provide practical guidance to the design and optimization of the photoanodes for DSCs.

  9. Printable electrolytes based on polyacrylonitrile and gamma-butyrolactone for dye-sensitized solar cell application

    NASA Astrophysics Data System (ADS)

    Venkatesan, Shanmugam; Su, Song-Chuan; Hung, Wei-Ning; Liu, I.-Ping; Teng, Hsisheng; Lee, Yuh-Lang

    2015-12-01

    Printable electrolytes for dye-sensitized solar cells (DSSCs) are prepared using a low volatile solvent, gamma-butyrolactone (gBL). Various polymers including polyvinyl acetate (PVA), polyacrylonotrile (PAN), and poly(acrylonitrile-co-vinylacetate) (PAN-VA) are used to regulate the viscosity of the electrolytes. The results show that PAN is the best polymer interms of viscosity, conductivity, and performance of the DSSCs. Increasing the concentration of PAN increases the viscosity of the electrolyte paste, which is advantageous to the operation of a printing process but decreases the electrolyte conductivity and cell performance. This drawback can be compensated by introducing of TiO2 or TiC nanofillers. The quasi-solid-state DSSC prepared using a printing process achieves a conversion efficiency (7.85%) similar to that of the corresponding liquid cell (7.87%). The stability test shows that the presence of TiO2 nanofillers triggers a gradual desorption of dye, decreasing DSSC performance. However, this problem does not appear for the electrolyte using TiC nanofillers, with cell efficiency retaining 96% of its initial value after a 500 h test.

  10. TiO2 hierarchical nanostructures: Hydrothermal fabrication and application in dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Liang, Jia; Zhang, Gengmin; Yang, Jin; Sun, Wentao; Shi, Mingji

    2015-01-01

    Arrays of TiO2 hierarchical nanostructures that consisted of rutile nanorods and anatase branches were hydrothermally fabricated and employed as photoanodes in dye-sensitized solar cells (DSSCs). Each hierarchical nanostructure array was attained in two steps. First, a primary nanorod array was synthesized in aqueous solutions of hydrochloric acid (HCl) and tetrabutyl titanate (C16H36O4Ti); subsequently, secondary branches were grown on the nanorods in aqueous solutions of ammonium hexafluorotitanate ((NH4)2TiF6) and boric acid (H3BO3). The secondary anatase branches filled part of the space among the primary rutile nanorods and gave rise to a larger surface area. Light-harvesting capability of the DSSCs with TiO2 hierarchical nanostructures as photoanodes was appreciably improved because more dye molecules could be loaded on the photoanodes and more light could be scattered inside the DSSCs. Therefore, the conversion efficiencies of the DSSCs were doubled by replacing the photoanode of primary TiO2 nanorod array with the photoanodes of TiO2 hierarchical nanostructure arrays. Furthermore, in order to reach a compromise between the photoanode surface area and the inter-nanorod space volume, the growth time of the secondary TiO2 anatase branches was optimized.

  11. Realizing omnidirectional light harvesting by employing hierarchical architecture for dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Hsieh, Ming-Yang; Lai, Fang-I.; Chen, Wei-Chun; Hsieh, Min-Chi; Hu, Hsiang-Yi; Yu, Peichen; Kuo, Hao-Chung; Kuo, Shou-Yi

    2016-03-01

    To improve the omnidirectional light-harvesting in dye-sensitized solar cells (DSSCs), here we present a dandelion-like structure composed of ZnO hemispherical shells and nanorods. Uniformly distributed hemispherical shells effectively suppress the reflection over the broadband region at incident angles up to 60°, greatly improving the optical absorption of the DSSCs. In addition, modulating the length of the ZnO nanorods controls the omnidirectional characteristics of DSSCs. This phenomenon is attributed to the degree of periodicity of the ZnO dandelion-like structures. Cells with shorter rods exhibit a high degree of periodicity, thus the conversion efficiencies of the cells show specific angle-independent features. On the other hand, the cells with longer lengths reveal angle-dependent photovoltaic performance. Along with the simulation, the cells with dandelion-like ZnO structures can couple incident photons efficiently to achieve excellent broadband and omnidirectional light-harvesting performances experimentally, and the DSSCs enhanced the conversion efficiency by 48% at large incident angles. All these findings not only provide further insight into the light-trapping mechanism in these complex three-dimensional nanostructures but also offer efficient omnidirectional and broadband nanostructured photovoltaics for advanced applications.

  12. Dye-sensitized solar cells using natural dyes as sensitizers from Malaysia local fruit `Buah Mertajam'

    NASA Astrophysics Data System (ADS)

    Hambali, N. A. M. Ahmad; Roshidah, N.; Hashim, M. Norhafiz; Mohamad, I. S.; Saad, N. Hidayah; Norizan, M. N.

    2015-05-01

    We experimentally demonstrate the high conversion efficiency, low cost, green technology and easy to fabricate dye-sensitized solar cells (DSSCs) using natural anthocyanin dyes as sensitizers. The DSSCs was fabricated by using natural anthocyanin dyes which were extracted from different parts of the plants inclusive `Buah Mertajam', `Buah Keriang Dot', `Bunga Geti', Hibiscus, Red Spinach and Henna. The natural anthocyanin dyes that found in flower, leaves and fruits were extracted by the simple procedures. This anthocyanin dye is used to replace the expensive chemical synthetic dyes due to its ability to effectively attach into the surface of Titanium dioxide (TiO2). A natural anthocyanin dyes molecule adsorbs to each particle of the TiO2 and acts as the absorber of the visible light. A natural anthocyanin dye from Buah Mertajam shows the best performance with the conversion efficiency of 5.948% and fill factor of 0.708 followed by natural anthocyanin dyes from `Buah Keriang Dot', `Bunga Geti', Hibiscus, Red Spinach and Henna. Buah Mertajam or scientifically known as eriglossum rubiginosum is a local Malaysia fruit.

  13. Interface Engineering through Atomic Layer Deposition towards Highly Improved Performance of Dye-Sensitized Solar Cells

    PubMed Central

    Lu, Hao; Tian, Wei; Guo, Jun; Li, Liang

    2015-01-01

    A composite photoanode comprising ultralong ZnO nanobelts and TiO2 nanoparticles was prepared and its performance in dye-sensitized solar cells (DSSCs) was optimized and compared to the photoanode consisting of conventional TiO2 nanoparticles. The ultralong ZnO nanobelts were synthesized in high yield by a facile solution approach at 90 oC followed by annealing at 500 oC. The effect of the ratio of ZnO nanobelts to TiO2 nanoparticles on the light scattering, specific surface area, and interface recombination were investigated. An optimum amount of ZnO nanobelts enhanced the photon-conversion efficiency by 61.4% compared to that of the conventional TiO2 nanoparticles. To further reduce the recombination rate and increase the carrier lifetime, Atomic Layer Deposition (ALD) technique was utilized to coat a continuous TiO2 film surrounding the ZnO nanobelts and TiO2 nanoparticles, functioning as a barrier-free access of all electrons to conductive electrodes. This ALD treatment improved the interface contact within the whole photoanode system, finally leading to significant enhancement (137%) in the conversion efficiency of DSSCs. PMID:26238737

  14. Energy Storage via Polyvinylidene Fluoride Dielectric on the Counterelectrode of Dye-Sensitized Solar Cells.

    PubMed

    Huang, Xuezhen; Zhang, Xi; Jiang, Hongrui

    2014-02-15

    To study the fundamental energy storage mechanism of photovoltaically self-charging cells (PSCs) without involving light-responsive semiconductor materials such as Si powder and ZnO nanowires, we fabricate a two-electrode PSC with the dual functions of photocurrent output and energy storage by introducing a PVDF film dielectric on the counterelectrode of a dye-sensitized solar cell. A layer of ultrathin Au film used as a quasi-electrode establishes a shared interface for the I(-)/I3 (-) redox reaction and for the contact between the electrolyte and the dielectric for the energy storage, and prohibits recombination during the discharging period because of its discontinuity. PSCs with a 10-nm-thick PVDF provide a steady photocurrent output and achieve a light-to-electricity conversion efficiency (η) of 3.38%, and simultaneously offer energy storage with a charge density of 1.67 C g(-1). Using this quasi-electrode design, optimized energy storage structures may be used in PSCs for high energy storage density. PMID:24327797

  15. A novel hierarchical Pt- and FTO-free counter electrode for dye-sensitized solar cell

    PubMed Central

    2014-01-01

    A novel hierarchical Pt- and FTO-free counter electrode (CE) for the dye-sensitized solar cell (DSSC) was prepared by spin coating the mixture of TiO2 nanoparticles and poly(3,4-ethylenedioxy-thiophene):poly(styrenesulfonate) (PEDOT:PSS) solution onto the glass substrate. Compared with traditional Pt/FTO CE, the cost of the new CE is dramatically reduced by the application of bilayer TiO2-PEDOT:PSS/PEDOT:PSS film and the glass substrate. The sheet resistance of this composite film is 35 Ω sq−1 and is low enough to be used as an electrode. The surface morphologies of TiO2-PEDOT:PSS layer and modified PEDOT:PSS layer were characterized by scanning electron microscope, which shows that the former had larger surface areas than the latter. Electrochemical impedance spectra and Tafel polarization curves prove that the catalytic activity of TiO2-PEDOT:PSS/PEDOT:PSS/glass CE is higher than that of PEDOT:PSS/FTO CE and is similar to Pt/FTO CE's. This new fabricated device with TiO2-PEDOT:PSS/PEDOT:PSS/glass CE achieves a high power conversion efficiency (PCE) of 4.67%, reaching 91.39% of DSSC with Pt/FTO CE (5.11%). PMID:24808802

  16. Improved Photovoltaic Properties of Dye-Sensitized Solar Cells with KNO3-Modified Photoelectrodes.

    PubMed

    Oh, Ju Hee; Lee, Sang-Ju; Kim, Dae-Hwan; Sung, Shi-Joon; Lee, Min Ho; Han, Yoon Soo

    2015-11-01

    The surface of a TiO2 photoelectrode was modified through a dip-coating process using an aqueous potassium nitrate (KNO3) solution to increase the power-conversion efficiency of dye-sensitized solar cells (DSSCs). The KNO3-modified TiO2 electrode was applied to the photoanode of the DSSCs. The DSSC with the KNO3-modified TiO2 electrode exhibited a short-circuit current (J(sc)) of 15.26 mA/cm2 and an open-circuit voltage (V(oc)) of 671 mV, compared with a J(sc) of 13.74 mA/cm2 and V(oc) of 654 mV for a reference device with a pristine TiO2 electrode. The results in combination with relevant data from electrochemical impedance spectroscopy, open-circuit voltage decay, and dark current measurements revealed that the modification of the TiO2 surface using the surface modifier (KNO3) led to a longer electron lifetime by the suppression of the charge recombination between injected electrons and I3- ions, resulting in an increase in both J(sc) and V(oc), compared with those of the reference device without surface modification. PMID:26726607

  17. Efficient synthesis of triarylamine-based dyes for p-type dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Wild, Martin; Griebel, Jan; Hajduk, Anna; Friedrich, Dirk; Stark, Annegret; Abel, Bernd; Siefermann, Katrin R.

    2016-05-01

    The class of triarylamine-based dyes has proven great potential as efficient light absorbers in inverse (p-type) dye sensitized solar cells (DSSCs). However, detailed investigation and further improvement of p-type DSSCs is strongly hindered by the fact that available synthesis routes of triarylamine-based dyes are inefficient and particularly demanding with regard to time and costs. Here, we report on an efficient synthesis strategy for triarylamine-based dyes for p-type DSSCs. A protocol for the synthesis of the dye-precursor (4-(bis(4-bromophenyl)amino)benzoic acid) is presented along with its X-ray crystal structure. The dye precursor is obtained from the commercially available 4(diphenylamino)benzaldehyde in a yield of 87% and serves as a starting point for the synthesis of various triarylamine-based dyes. Starting from the precursor we further describe a synthesis protocol for the dye 4-{bis[4‧-(2,2-dicyanovinyl)-[1,1‧-biphenyl]-4-yl]amino}benzoic acid (also known as dye P4) in a yield of 74%. All synthesis steps are characterized by high yields and high purities without the need for laborious purification steps and thus fulfill essential requirements for scale-up.

  18. Additives and salts for dye-sensitized solar cells electrolytes: what is the best choice?

    NASA Astrophysics Data System (ADS)

    Bella, Federico; Sacco, Adriano; Pugliese, Diego; Laurenti, Marco; Bianco, Stefano

    2014-10-01

    A multivariate chemometric approach is proposed for the first time for performance optimization of I-/I3- liquid electrolytes for dye-sensitized solar cells (DSSCs). Over the years the system composed by iodide/triiodide redox shuttle dissolved in organic solvent has been enriched with the addition of different specific cations and chemical compounds to improve the photoelectrochemical behavior of the cell. However, usually such additives act favorably with respect to some of the cell parameters and negatively to others. Moreover, the combined action of different compounds often yields contradictory results, and from the literature it is not possible to identify an optimal recipe. We report here a systematic work, based on a multivariate experimental design, to statistically and quantitatively evaluate the effect of different additives on the photovoltaic performances of the device. The effect of cation size in iodine salts, the iodine/iodide ratio in the electrolyte and the effect of type and concentration of additives are mutually evaluated by means of a Design of Experiment (DoE) approach. Through this statistical method, the optimization of the overall parameters is demonstrated with a limited number of experimental trials. A 25% improvement on the photovoltaic conversion efficiency compared with that obtained with a commercial electrolyte is demonstrated.

  19. Theoretical studies on the quinoidal thiophene based dyes for dye sensitized solar cell and NLO applications.

    PubMed

    Nithya, R; Senthilkumar, K

    2014-10-21

    A series of quinoidal thiophene based dye molecules were designed and their optoelectronic properties were studied for dye sensitized solar cell (DSSC) applications. The efficiency of the designed dye molecules was analyzed using various parameters such as the HOMO-LUMO energy gap, absorption spectra, light harvesting efficiency (LHE), exciton biding energy (Eb) and free energy change for electron injection (ΔG(inject)). The simulated absorption spectra of the quinoidal thiophene molecules show that the electron withdrawing group substituted molecules exhibit dual band characteristics. We found that the cyano-[5'-(4″-amino benzylidene)-5H-thiophen-2'-ylidene] acetic acid based molecules, QT2B, QT4B, QT5 and QT6, are good candidates for DSSC applications. Furthermore, the study on the polarizability and hyperpolarizability of the designed molecules showed that the electron withdrawing group substituted QT2B-X molecules (X = Cl, Br, CF3, CN and NO2) are good candidates for NLO applications.

  20. Graphite nanoplatelet assemblies for transparent and catalytic electrodes in dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Aderhold, Patrick

    Dye sensitized solar cells (DSSCs) are a class of photovoltaic devices that have the potential to provide high conversion efficiency at low production cost. Research to improve performance in the individual components is active, but attention must be paid to methods that improve scalability and production cost as well. Graphite nanoplatelets (GNP), thin stacks of graphene sheets with nanometer-scale thickness and micron-scale lateral dimensions, provide a unique opportunity for creating DSSC electrodes with simple manufacturing techniques and low-energy processing. For the counterelectrode, a composite paper, made by cofiltration and pressing of GNP and polypropylene (PP), yields a highly electrical conductive surface that is mechanically robust and chemically stable in electrolyte. Decoration of this surface with platinum nanoparticles (PtNPs) by a rapid microwave heating process produces a catalytic surface that rivals the current "thermalized" platinum standard counterelectrode. The GNP/PP/PtNP system, however, requires lower processing temperature and requires a fraction of the Pt loading. For the transparent electrode, thin sheets of GNP can be deposited on glass surfaces to create highly transparent coatings for use in photoanode construction. Substrate interactions and post treatments are examined and techniques for optimization are outlined. Overall GNP is shown to be a versatile and effective starting material for DSSC electrode construction and demonstrates its potential as a building-block in next-generation photovoltaic devices.

  1. Carbon nanotube/graphene nanocomposite as efficient counter electrodes in dye-sensitized solar cells.

    PubMed

    Velten, Josef; Mozer, Attila J; Li, Dan; Officer, David; Wallace, Gordon; Baughman, Ray; Zakhidov, Anvar

    2012-03-01

    We demonstrated the replacement of the Pt catalyst normally used in the counter electrode of a dye-sensitized solar cell (DSSC) by a nanocomposite of dry spun carbon multi-walled nanotube (MWNT) sheets with graphene flakes (Gr-F). The effectiveness of this counter electrode on the reduction of the triiodide in the iodide/triiodide redox (I(-)/I(3)(-)) redox reaction was studied in parallel with the use of the dry spun carbon MWNT sheets alone and graphene flakes used independent of each other. This nanocomposite deposited onto fluorinated tin-oxide-coated glass showed improved catalytic behavior and power conversion efficiency (7.55%) beyond the use of the MWNTs alone (6.62%) or graphene alone (4.65%) for the triiodide reduction reaction in DSSC. We also compare the use of the carbon MWNT/Gr-F composite counter electrode with a DSSC using the standard Pt counter electrode (8.8%). The details of increased performance of graphene/MWNT composite electrodes as studied are discussed in terms of increased catalytic activity permitted by sharp atomic edges that arise from the structure of graphene flakes or the defect sites in the carbon MWNT and increased electrical conductivity between the carbon MWNT bundles by the graphene flakes. PMID:22293392

  2. Thermally exfoliated graphene based counter electrode for low cost dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Kaniyoor, Adarsh; Ramaprabhu, Sundara

    2011-06-01

    Graphene obtained from thermal exfoliation of graphite oxide are highly wrinkled and have large surface area. Their wrinkled nature is expected to give them excellent catalytic activity. Herein, we demonstrate the use of thermally exfoliated graphene (TEG) as cost effective electrocatalyst for the tri-iodide reduction in dye sensitized solar cells (DSSCs). X-ray diffraction, Raman and Infra red spectroscopy and electron microscopy studies confirm the defective and wrinkled nature of TEG. BET surface area measurement show a large surface area of ˜ 470 m2/g. The counter electrode was fabricated by drop casting a slurry of TEG dispersed in a Nafion:Ethanol solution on fluorine doped tin oxide (FTO) substrates. The use of Nafion prevented film "peel off," thus ensuring a good substrate adhesion. Electrochemical impedance spectroscopy reveals that TEG had a catalytic performance comparable to that of Pt, suggesting its use as counter electrode material. As expected, the DSSC fabricated with Nafion solubilized TEG/FTO as counter electrode shows an efficiency of about 2.8%, comparable to Pt counter electrode based DSSC which has an efficiency of about 3.4%.

  3. Properties of Dye-Sensitized Solar Cells Using Carbon Nanowall Counter Electrodes.

    PubMed

    Jung, Y H; Jang, J H; Kang, H; Choi, W S; Choi, Y K; Song, W C; Song, B S; Lee, J H; Hong, B

    2016-05-01

    This research investigates plasma-treated and metal-coated carbon nanowalls (CNWs) for use as counter electrodes of dye-sensitized solar cells (DSSCs). The CNWs were synthesized on a fluorine-tin-oxide (FTO) glass substrate using the microwave plasma-enhanced chemical vapor deposition (PECVD) system with methane (CH4) gas. The post-plasma treatment was performed on the CNWs with hydrogen (H2) plasma using PECVD, and the CNWs were sputter-coated with metal films using the RF magnetron sputtering system with a four-inch tungsten (W) target. Then the post-plasma-treated and metal-coated CNWs were used as counter electrodes for the fabrication of the DSSCs. Field-emission scanning electron microscopy (FE-SEM) was performed to obtain cross-sectional and planar images of the grown CNWs. The energy conversion efficiencies of the DSSCs manufactured using the post-plasma-treated and metal-layer-coated CNWs as the counter electrodes were measured. PMID:27483920

  4. Ligand Engineering for the Efficient Dye-Sensitized Solar Cells with Ruthenium Sensitizers and Cobalt Electrolytes.

    PubMed

    Aghazada, Sadig; Gao, Peng; Yella, Aswani; Marotta, Gabriele; Moehl, Thomas; Teuscher, Joël; Moser, Jacques-E; De Angelis, Filippo; Grätzel, Michael; Nazeeruddin, Mohammad Khaja

    2016-07-01

    Over the past 20 years, ruthenium(II)-based dyes have played a pivotal role in turning dye-sensitized solar cells (DSCs) into a mature technology for the third generation of photovoltaics. However, the classic I3(-)/I(-) redox couple limits the performance and application of this technique. Simply replacing the iodine-based redox couple by new types like cobalt(3+/2+) complexes was not successful because of the poor compatibility between the ruthenium(II) sensitizer and the cobalt redox species. To address this problem and achieve higher power conversion efficiencies (PCEs), we introduce here six new cyclometalated ruthenium(II)-based dyes developed through ligand engineering. We tested DSCs employing these ruthenium(II) complexes and achieved PCEs of up to 9.4% using cobalt(3+/2+)-based electrolytes, which is the record efficiency to date featuring a ruthenium-based dye. In view of the complicated liquid DSC system, the disagreement found between different characterizations enlightens us about the importance of the sensitizer loading on TiO2, which is a subtle but equally important factor in the electronic properties of the sensitizers. PMID:27322854

  5. Mondo Grass Berry Pigment for Visible to Near Infrared Absorption in Dye Sensitized Solar Cell

    NASA Astrophysics Data System (ADS)

    Desilva, L. A. A.; Pitigala, P. K. D. D. P.; Perera, A. G. U.

    2013-03-01

    The development of dye sensitized solar cells (DSSC) is an exciting field in the low cost renewable energy production. Two major draw backs in the DSSCs are the narrow spectral response and the short term stability. Synthesis of artificial dyes with broad response is important in developing an efficient DSSC. Artificial dyes can add up to the cost of the device; therefore, it is important to identify natural dyes with broad abortion and required energy levels. Work presented here shows a broad spectral response with a natural dye extracted from a Mondo Grass berry (Ophiopogonjaponicus).The dye is extracted by crushing the berries and filtering to remove the pulp. A DSSC sensitized with Mondo Grass dye, and with TiO2 film screen printed on a Florien doped Tin Oxide (FTO) glass and baked for 30 minutes at 450 degree C as the working electrode and Iodine/triiodide red-ox electrolyte as the hole collector was tested for its performance. An open circuit photovoltage of 495 mV and a short circuit photocurrent of 0.6 mA/cm2 were observed under a simulated lamp equivalent to 1 sun illumination and have a broad spectral response extending from 400 nm to 750 nm. This work is supported by COSM at UWG.

  6. Preparation of 1-methyl-3-propylimidazolium acetate and its application in dye sensitized solar cells

    SciTech Connect

    Zhang, Zhihai; Wu, Yucheng; Ge, Qian; Sun, Songquan; Shi, Chengwu

    2010-03-15

    In this paper, we reported the preparation of 1-methyl-3-propylimidazolium acetate (MPIAc), which proceeded via the metathesis of 1-methyl-3-propylimidazolium iodide (MPII) and lead acetate or potassium acetate. The apparent diffusion coefficients of triiodide and iodide in binary ionic liquids, MPIAc and MPII with various weight ratios, were demonstrated by cyclic voltammetry using a Pt ultramicroelectrode. It was found that the apparent diffusion coefficients of triiodide increased and those of iodide slightly increased with the weight ratio increase of MPIAc and MPII. The dye sensitized solar cells with the electrolyte, which was composed of 0.13 M I{sub 2}, 0.10 M LiI, 0.50 M 4-tert-butylpyrdine in the binary ionic liquid electrolyte of MPIAc (employing potassium acetate) and MPII (weight ratio 0.2), gave short circuit photocurrent density of 9.40 mA cm{sup -2}, open circuit voltage of 0.62 V, and fill factor of 0.57, corresponding to the photoelectric conversion efficiency of 3.34% at the illumination (air mass 1.5, 100 mW cm{sup -2}). (author)

  7. Charge transport through split photoelectrodes in dye-sensitized solar cells

    SciTech Connect

    Fakharuddin, Azhar; Ahmed, Irfan; Yusoff, Mashitah M.; Jose, Rajan; Khalidin, Zulkeflee

    2014-04-28

    Charge transport and recombination are relatively ignored parameters while upscaling dye-sensitized solar cells (DSCs). Enhanced photovoltaic parameters are anticipated by merely widening the devices physical dimensions, viz., thickness and area as evident from the device design adopted in reported large area DSCs. These strip designs lead to ≤50% loss in photocurrent compared to the high efficiency lab scale devices. Herein, we report that the key to achieving higher current density (J{sub SC}) is optimized diffusion volume rather than the increased photoelectrode area because kinetics of the devices is strongly influenced by the varied choices of diffusion pathways upon increasing the electrode area. For a given electrode area and thickness, we altered the photoelectrode design by splitting the electrode into multiple fractions to restrict the electron diffusion pathways. We observed a correlation between the device physical dimensions and its charge collection efficiency via current-voltage and impedance spectroscopy measurements. The modified electrode designs showed >50% increased J{sub SC} due to shorter transport time, higher recombination resistance and enhanced charge collection efficiency compared to the conventional ones despite their similar active volume (∼3.36 × 10{sup −4} cm{sup 3}). A detailed charge transport characteristic of the split devices and their comparison with single electrode configuration is described in this article.

  8. Doped In₂O₃ inverse opals as photoanode for dye sensitized solar cells.

    PubMed

    Kong, Lingxin; Dai, Qilin; Miao, Chuang; Xu, Lin; Song, Hongwei

    2015-07-15

    One promising way to improve the power conversion efficiency (PCE) of dye-sensitized solar cells (DSSCs), which have attracted great interest due to their low cost, is modifying the working electrode. In this work, Tm and Yb doped as well as undoped In2O3 inverse opals (IOs) were synthesized by the sol-gel method. DSSCs based on In2O3, In2O3:Tm and In2O3:Yb IOs as photoanodes were fabricated and studied. It is observed that the device performance including open-circuit voltage (V(oc)) and short-circuit current (J(sc)) increased largely with the increasing pore size of the IOs and the introduction of Tm and Yb elements in the In2O3 lattices. The PCE of the DSSC was increased from 0.33% to 0.96% when the ln2O3 IOs photoanode was substituted by ln2O3:Yb IOs. The electrochemical impedance spectroscopy (EIS) measurements indicate that the modification of band gap in the Tm and Yb doped In2O3 IOs is significant for the improved performance, which can effectively suppress the charge transfer recombination and improve the electron lifetime.

  9. Application of mesoporous carbon to counter electrode for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Wang, Guiqiang; Xing, Wei; Zhuo, Shuping

    The mesoporous carbons were prepared by the carbonation of the triblock copolymer F127/phloroglucinol-formaldehyde composite self-assembled in an acid medium and employed as the catalyst for triiodide reduction in dye-sensitized solar cells (DSCs). The characteristics of mesoporous carbon were analyzed by scanning electron microscopy, transmission electron microscopy, N 2 sorption measurement and X-ray diffraction. The mesoporous carbon with low crystallinity exhibited Brunauer-Emmett-Teller surface area of 400 m 2 g -1, pore diameter of 6.8 nm and pore volume of 0.63 cm 3 g -1. The photovoltaic performances of DSCs with mesoporous carbon counter electrode were improved by increasing the carbon loading on counter electrode due to the charge-transfer resistance of mesoporous carbon counter electrode decreasing with the increase of the carbon loading. However, further carbon loading increase has no obvious effect on the photovoltaic performance of DSCs with carbon electrode when carbon loading exceeds 300 μg cm -2. The overall conversion efficiency of 6.18% was obtained by DSCs composed of mesoporous carbon counter electrode with the carbon loading of 339 μg cm -2. This value is comparable to that of DSCs with conventional platinum counter electrode.

  10. Polyiodides formation in solvent based Dye Sensitized Solar Cells under reverse bias stress

    NASA Astrophysics Data System (ADS)

    Agresti, Antonio; Pescetelli, Sara; Gatto, Emanuela; Venanzi, Mariano; Di Carlo, Aldo

    2015-08-01

    In this work we investigate electrolyte degradation mechanisms in a Dye Sensitized Solar Cell (DSSC), when stressed under forced reverse bias (RB) conditions. During the stress test, we observe a gradual and visually evident cluster shaped browning of platinised counter-electrode in contact with electrolyte solution; Raman spectroscopy confirms that the observed phenomena is due to formation of polyiodide ions and reveals an arose marked fluorescence background, stemming from new chemical species induced by RB stress test. Raman and fluorescence measurements on RB stressed model electrolyte solutions reveal that photoluminescence emission is mainly related to degradation mechanisms involving the I-/I3- redox couple. In fact, due to the RB stress, the redox couple is unbalanced and the formation of various associated structures between 1-methyl-3-propyl imidazolium iodide (PMII) ions is favored. This can be detected by observing the Red Edge Effect (REE) in fluorescence emission spectra of stressed solutions. Thus, polyiodides formation in RB stressed DSSCs could be added to the several depletion channels of triiodide anions and should be taken into account in designing new stable and efficient electrolytes.

  11. Enhanced performance of dye-sensitized solar cells using gold nanoparticles modified fluorine tin oxide electrodes

    NASA Astrophysics Data System (ADS)

    Zhang, Dingwen; Wang, Milton; Brolo, Alexandre G.; Shen, Jie; Li, Xiaodong; Huang, Sumei

    2013-01-01

    We have investigated plasmon-assisted energy conversion in dye-sensitized solar cells (DSCs) applying gold nanoparticles (NPs) modified fluorine tin oxide (FTO) electrodes. A series of Au NPs with different sizes (15-80 nm) were synthesized and immobilized onto FTO glass slides. Photoanodes were prepared on these Au modified FTO substrates using P25 TiO2 powders and by the screen-printing method. The size effects of Au NPs on the photovoltaic performance of the formed DSCs were investigated systematically. Structural and photoelectrochemical properties of the formed photoanodes were examined by field emission scanning electron microscopy and electrochemical impedance spectroscopy. It was found that the energy conversion efficiency of the DSC was highly dependent on the Au particle size. When the particle size was not greater than 60 nm, the DSC based on the Au NP-FTO composite electrode showed a higher short-circuit current density and better photovoltaic (PV) performance than the cell based on the bare FTO. The best cell was achieved using 25 nm sized Au NPs modified FTO. It exhibited a conversion efficiency of 6.69%, which was 15% higher than that of DSCs without Au NPs. The related PV performance enhancement mechanisms, photoelectrochemical processes and surface-plasmon resonances in DSCs with Au nanostructures are analysed and discussed.

  12. Theoretica Study of Asymmetric Double D-π-A Organic Sensitizers for Efficient Dye-Sensitized Solar Cells.

    PubMed

    Kwon, Dong Yuel; Lee, Gun Hyung; Kim, Young Sik

    2015-03-01

    Three novel dye sensitizers that were based on asymmetric double D-π-A chains with phenoxazine (POZ) and diphenylamine (DPA) as electron donors and cyanoacetic acid (CA) and 2-(1,1- dicyanomethylene) rhodanine (RD) as electron acceptors (DCPR, DRPC, DRPR) were designed, theoretically investigated, and compared with the reference dye based on asymmetric double D-π-A chains (DCPC). Using density functional theory (DFT) and time-dependent density functional theory (TD-DFT) calculations, we gained insight into the factors responsible for the photovoltaic properties of the dye sensitizers. Due to the different HOMO levels of each donor and the different LUMO levels of each acceptor, the absorption spectrum of each dye showed different shapes. Among the dyes, DRPR showed a broader and more bathochromically shifted absorption band than the other dies. It also showed a higher molar extinction coefficient than that of the reference dye (DCPC). This work suggests optimizing the chain of electron donors and acceptors in dye sensitizers based on asymmetric double D-π-A chains would produce good photovoltaic properties for dye-sensitized solar cells (DSSCs).

  13. Role of temperature in the recombination reaction on dye-sensitized solar cells.

    PubMed

    Maçaira, J; Mesquita, I; Andrade, L; Mendes, A

    2015-09-21

    The performance of photovoltaic (PV) devices as a function of temperature is crucial for technical development and for accurate commercial information. Along with solar irradiance, temperature is the most important operating factor of the PV device performance. Normally, it is widely accepted that dye sensitized solar cells (DSC) show minimal energy efficiency dependence with temperature (20-60 °C). The energy efficiency in DSCs depends on the light absorption, charge transport (ohmic resistances) and recombination rates. In this study, the recombination reaction kinetics was studied within a wide temperature range. A unique laser assisted sealing technique that allows studying the temperature effect between -5 °C and 105 °C without electrolyte leakage or external contamination was used. To the best of our knowledge, this is the highest operating temperature ever considered in kinetic studies of liquid state DSCs. The electrochemical reaction between electrons and triiodide/iodide ions was shown to be the most important factor for determining the energy efficiency of DSCs as a function of temperature. It was concluded that the activation energy of the recombination reactions depends on the interface where it happens - TiO2/electrolyte and SnO2-F/electrolyte - and on the temperature. It was found that in addition to temperature having a deep influence on the recombination reaction rate, the energy of the injecting electron is also critical. These conclusions should provide solid ground for further developments in the DSCs and perovskite solar cells, and allow a better comparison of the energy efficiency of different PV technologies over a range of operating temperatures.

  14. Role of temperature in the recombination reaction on dye-sensitized solar cells.

    PubMed

    Maçaira, J; Mesquita, I; Andrade, L; Mendes, A

    2015-09-21

    The performance of photovoltaic (PV) devices as a function of temperature is crucial for technical development and for accurate commercial information. Along with solar irradiance, temperature is the most important operating factor of the PV device performance. Normally, it is widely accepted that dye sensitized solar cells (DSC) show minimal energy efficiency dependence with temperature (20-60 °C). The energy efficiency in DSCs depends on the light absorption, charge transport (ohmic resistances) and recombination rates. In this study, the recombination reaction kinetics was studied within a wide temperature range. A unique laser assisted sealing technique that allows studying the temperature effect between -5 °C and 105 °C without electrolyte leakage or external contamination was used. To the best of our knowledge, this is the highest operating temperature ever considered in kinetic studies of liquid state DSCs. The electrochemical reaction between electrons and triiodide/iodide ions was shown to be the most important factor for determining the energy efficiency of DSCs as a function of temperature. It was concluded that the activation energy of the recombination reactions depends on the interface where it happens - TiO2/electrolyte and SnO2-F/electrolyte - and on the temperature. It was found that in addition to temperature having a deep influence on the recombination reaction rate, the energy of the injecting electron is also critical. These conclusions should provide solid ground for further developments in the DSCs and perovskite solar cells, and allow a better comparison of the energy efficiency of different PV technologies over a range of operating temperatures. PMID:26256850

  15. Saddle-shaped porphyrins for dye-sensitized solar cells: new insight into the relationship between nonplanarity and photovoltaic properties.

    PubMed

    Shahroosvand, Hashem; Zakavi, Saeed; Sousaraei, Ahmad; Eskandari, Mortaza

    2015-03-01

    We report on the theoretical and experimental studies of the new dye-sensitized solar cells functionalized with 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin zinc(II) complexes bearing 2- and 8-bromo substituents at the β positions. In agreement with the results of TD-DFT calculations, the absorption maxima of di- and octa-brominated Zn(II) complexes, ZnTCPPBr2 and ZnTCPPBr8, exhibited large red-shift compared to that of the non-brominated free base porphyrin (H2TCPP). Furthermore, DFT calculations showed that the higher stabilization of the LUMO levels relative to the HOMO ones makes the HOMO-LUMO gap of the brominated Zn-porphyrins models smaller compared to that of the nonbrominated counterparts, which explains the red shifts of the Soret and Q bands of the brominated compounds. Solar cells containing the new saddle-shaped Zn(II) porphyrins were subjected to analysis in a photovoltaic calibration laboratory to determine their solar to electric energy conversion. In this regard, we found that the overall conversion efficiency of ZnTCPPBr8 adsorbed on TiO2 nanocrystalline films was 5 times as large as that of ZnTCPPBr2 adsorbed on the same films. The effect of the increasing number of Br groups on the photovoltaic performance of the complexes was compared to the results of computational methods using ab initio DFT molecular dynamics simulations and quantum dynamics calculations of electronic relaxation to investigate the interfacial electron transfer (IET) in TCPPBrx/TiO2-anatase nanostructures. Better IET in ZnTCPPBr8 compared to ZnTCPPBr2, and in H2TCPP was evaluated from interfacial electron transfer (IET) simulations. The IET results indicate that electron injection in ZnTCPPBr8-TiO2 (τ = 25 fs) can be up to 5 orders of magnitude faster than ZnTCPPBr2-TiO2 (τ = 125 fs). Both experimental and theoretical results demonstrate that the increase of the number of bromo-substituents at the β-pyrrole positions of the porphyrin macrocycle created a new class of

  16. Design and development of efficient solid-state dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Yuan, Wen

    Organic photovoltaic cell is the most promising one in the third generation solar cell. Considering the materials used for fabricating devices, it generally can be classified as two sorts. One is called full organic solar cell, which is all made by organic or polymeric molecules. The examples of this type of solar cell includes bulk heterojunction solar cell (BHJ solar cell). Another one is organic/inorganic hybrid solar cell, and most of them are composed of organic-inorganic blends. For instance, solid state dye sensitized solar cell (ss-DSSC) is made by porous dye-coated inorganic semiconductor and then infiltrating organic conductor into it. One of the most commonly-used organic hole conductor is spiro-MeOTAD (2, 2', 7, 7' -tetrakis (N, N-di-p-methoxyphenylamine) 9, 9'-spirobifluorene). The ss-DSSC made by spiro-MeOTAD already reached an average power conversion efficiency around 3-4% and a record efficiency of 7.2% from Gratzel's group. However it is still below a desired level for manufacturing usage. This dissertation presents three approaches to optimize the ss-DSSC: Increasing fill factor in ss-DSSC, enhancement of light harvesting and In the first part, we first provide an overview of doping in organic or polymeric materials. Subsequently, we discuss the prior literature on p-dopants and additives incorporated into ss-DSSCs. Finally we present our data that suggests the primary role of Lithium salts is to stabilize the oxidized state of the hole conductor. In the second part, we use surface-initiated polymerization to anchor hole conducting polymers onto silica nanoparticles. We argue that the formation of silica/polymer composites serve as a light scattering layer on the top of photoanode, raising the short circuit current by 26% over conventional spiro-MeOTAD ss-DSSCs. Finally, a simple strategy is presented which effectively increases the pore-filling fraction of spiro-MeOTAD into photoanode. Heating the cell during the fabrication process lowers the

  17. Growth of Multipod ZnO Architectures Made by Accumulation of Hexagonal Nanorods for Dye Sensitized Solar Cell (DSSC) Application.

    PubMed

    Umar, Ahmad

    2015-09-01

    Well-crystalline multipod ZnO architectures made by accumulation of hexagonal nanorods were synthesized, characterized and used as efficient anode material for the fabrication of dye-sensitized solar cell (DSSC). The multipod ZnO architectures were synthesized by simple and facile hydrothermal process and characterized by several techniques to examine the structural, morphological, optical and photovoltaic properties. The morphological characterizations revealed that the synthesized multipod ZnO architectures were made of several hexagonal shaped ZnO nanorods which are originated from a single centre. The structural and compositional properties revealed that the nanorods are pure ZnO and possessing well crystallinity and wurtzite hexagonal phase. The assynthesized multipods ZnO architectures were utilized as potential anode materials for the fabrication of dye-sensitized solar cell (DSSC). The dye sensitized solar cells fabricated with multipods ZnO architectures photoanode attained a reasonable solar to electricity energy conversion efficiency of -1.9% with a photocurrent density i.e., short circuit current (J(sc)) of 4.59 mA/cm2.

  18. Excellent anti-fogging dye-sensitized solar cells based on superhydrophilic nanoparticle coatings

    NASA Astrophysics Data System (ADS)

    Park, Jung Tae; Kim, Jong Hak; Lee, Daeyeon

    2014-06-01

    We present a facile method for producing anti-fogging (AF) and anti-reflection (AR) coating functionalized photoanodes via one-step SiO2 nanoparticle coating for high performance solid state dye-sensitized solar cells (ssDSSCs). The AF and AR coating functionalized photoanodes are prepared by spin-coating of partially aggregated SiO2 colloidal solution. Poly((1-(4-ethenylphenyl)methyl)-3-butyl-imidazolium iodide) (PEBII), prepared via free radical polymerization, is used as a solid electrolyte in I2-free ssDSSCs. We systematically investigate the enhanced light harvesting characteristics of AF and AR coating functionalized photoanode-based ssDSSCs by measuring UV-visible spectroscopy, incident photon-to-electron conversion efficiency (IPCE) curves under fogging conditions. Compared with conventional photoanode based ssDSSCs, the AF and AR coating functionalized photoanodes substantially suppress fogging and reduce reflection, leading to significantly enhanced light harvesting, especially under fogging conditions. ssDSSCs made of AF and AR coating functionalized photoanodes exhibit an improved photovoltaic efficiency of 6.0% and 5.9% under non-fogging and fogging conditions, respectively, and retain their device efficiencies for at least 20 days, which is a significant improvement of ssDSSCs with conventional photoanodes (4.7% and 1.9% under non-fogging and fogging conditions, respectively). We believe that AF and AR functionalization via one-step SiO2 colloidal coating is a promising method for enhancing light harvesting properties in various solar energy conversion applications.We present a facile method for producing anti-fogging (AF) and anti-reflection (AR) coating functionalized photoanodes via one-step SiO2 nanoparticle coating for high performance solid state dye-sensitized solar cells (ssDSSCs). The AF and AR coating functionalized photoanodes are prepared by spin-coating of partially aggregated SiO2 colloidal solution. Poly((1-(4-ethenylphenyl)methyl)-3

  19. Effect of TiO2 rutile nanorods on the photoelectrodes of dye-sensitized solar cells

    PubMed Central

    2013-01-01

    In order to enhance the electron transport on the photoelectrodes of dye-sensitized solar cells, one-dimensional rutile nanorods were prepared using electrospun TiO2 nanofibers. The grain size of the nanorods increased with increasing temperature. Electrochemical impedance spectroscopy measurements revealed reduced interface resistance of the cells with the one-dimensional rutile nanorods due to the improved electron transport and the enhanced electrolyte penetration. Intensity-modulated photocurrent/photovoltage spectroscopy showed that the one-dimensional rutile nanorods provided the electrons with a moving pathway and suppressed the recombination of photogenerated electrons. However, an excessive quantity of rutile nanorods created an obstacle to the electrons moving in the TiO2 thin film. The photoelectrode with 7 wt.% rutile nanorods optimized the performance of the dye-sensitized solar cells. PMID:23331863

  20. Pre dye treated titanium dioxide nanoparticles synthesized by modified sol-gel method for efficient dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Ananth, S.; Vivek, P.; Arumanayagam, T.; Murugakoothan, P.

    2015-06-01

    Pure and pre dye treated titanium dioxide nanoparticles were prepared by sol-gel and modified sol-gel methods, respectively. The pre dye treatment has improved the properties of TiO2, such as uniform dye adsorption, reduced agglomeration, improved morphology and less dye aggregation. The brazilein pigment-rich Caesalpinia sappan heartwood extract was used as natural dye sensitizer for pure and pre dye treated TiO2 nanoparticles. Low cost and environment friendly dye-sensitized solar cells (DSSC) fabricated using pure and pre dye treated TiO2 nanoparticles sensitized by natural dye showed solar light to electron conversion efficiencies of 1.09 and 1.65 %, respectively. The pre dye treated TiO2-based DSSC showed 51 % improvement in efficiency when compared to that of conventionally prepared DSSC.

  1. Ag nanoparticle-deposited TiO2 nanotube arrays for electrodes of Dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Kawamura, Go; Ohmi, Hayato; Tan, Wai Kian; Lockman, Zainovia; Muto, Hiroyuki; Matsuda, Atsunori

    2015-05-01

    Dye-sensitized solar cells composed of a photoanode of Ag nanoparticle (NP)-deposited TiO2 nanotube (TNT) arrays were fabricated. The TNT arrays were prepared by anodizing Ti films on fluorine-doped tin oxide (FTO)-coated glass substrates. Efficient charge transportation through the ordered nanostructure of TNT arrays should be carried out compared to conventional particulate TiO2 electrodes. However, it has been a big challenge to grow TNT arrays on FTO glass substrates with the lengths needed for sufficient light-harvesting (tens of micrometers). In this work, we deposited Ag nanoparticles (NPs) on the wall of TNT arrays to enhance light-harvesting property. Dye-sensitized solar cells with these Ag NP-deposited TNT arrays yielded a higher power conversion efficiency (2.03 %) than those without Ag NPs (1.39 %).

  2. High performance low temperature carbon composite catalysts for flexible dye sensitized solar cells.

    PubMed

    Hashmi, Syed Ghufran; Halme, Janne; Saukkonen, Tapio; Rautama, Eeva-Leena; Lund, Peter

    2013-10-28

    Roll-to-roll manufacturing of dye sensitized solar cells (DSSCs) requires efficient and low cost materials that adhere well on the flexible substrates used. In this regard, different low temperature carbon composite counter electrode (CE) catalyst ink formulations for flexible DSSCs were developed that can be simply and quickly coated on plastic substrates and dried below 150 °C. The CEs were investigated in terms of photovoltaic performance in DSSCs by current-voltage measurements, mechanical adhesion properties by bending and tape tests, electro-catalytic performance by electrochemical impedance spectroscopy and microstructure by electron microscopy. In the bending and tape tests, PEDOT-carbon composite catalyst layers exhibited higher elasticity and better adhesion on all the studied substrates (ITO-PET and ITO-PEN plastic, and FTO-glass), compared to a binder free carbon composite and a TiO2 binder enriched carbon composite, and showed lower charge transfer resistance (1.5-3 Ω cm(2)) than the traditional thermally platinized CE (5 Ω cm(2)), demonstrating better catalytic performance for the tri-iodide reduction reaction. Also the TiO2 binder enriched carbon composite showed good catalytic characteristics and relatively good adhesion on ITO-PET, but on ITO-PEN its adhesion was poor. A DSSC with the TiO2 binder enriched catalyst layer reached 85% of the solar energy conversion efficiency of the reference DSSC based on the traditional thermally platinized CE. Based on the aforementioned characteristics, these carbon composites are promising candidates for replacing the platinum catalyst in a high volume roll-to-roll manufacturing process of DSSCs. PMID:24042582

  3. Enhanced Electron Lifetimes in Dye-Sensitized Solar Cells Using a Dichromophoric Porphyrin: The Utility of Intermolecular Forces.

    PubMed

    Zhao, Long; Wagner, Pawel; van der Salm, Holly; Gordon, Keith C; Mori, Shogo; Mozer, Attila J

    2015-10-01

    Electron lifetimes in dye-sensitized solar cells employing a porphyrin dye, an organic dye, a 1:1 mixture of the two dyes, and a dichromophoric dye design consisting of the two dyes using a nonconjugated linker were measured, suggesting that the dispersion force of the organic dyes has a significant detrimental effect on the electron lifetime and that the dichromophoric design can be utilized to control the effect of the dispersion force.

  4. A metal-free N-annulated thienocyclopentaperylene dye: power conversion efficiency of 12% for dye-sensitized solar cells.

    PubMed

    Yao, Zhaoyang; Zhang, Min; Li, Renzhi; Yang, Lin; Qiao, Yongna; Wang, Peng

    2015-05-11

    Reported are two highly efficient metal-free perylene dyes featuring N-annulated thienobenzoperylene (NTBP) and N-annulated thienocyclopentaperylene (NTCP), which are coplanar polycyclic aromatic hydrocarbons. Without the use of any coadsorbate, the metal-free organic dye derived from the NTCP segment was used for a dye-sensitized solar cell which attained a power conversion efficiency of 12% under an irradiance of 100 mW cm(-2), simulated air mass global (AM1.5G) sunlight.

  5. Wurtzite copper-zinc-tin sulfide as a superior counter electrode material for dye-sensitized solar cells

    PubMed Central

    2013-01-01

    Wurtzite and kesterite Cu2ZnSnS4 (CZTS) nanocrystals were employed as counter electrode (CE) materials for dye-sensitized solar cells (DSSCs). Compared to kesterite CZTS, the wurtzite CZTS exhibited higher electrocatalytic activity for catalyzing reduction of iodide electrolyte and better conductivity. Accordingly, the DSSC with wurtzite CZTS CE generated higher power conversion efficiency (6.89%) than that of Pt (6.23%) and kesterite CZTS (4.89%) CEs. PMID:24191954

  6. Accurate control of multishelled ZnO hollow microspheres for dye-sensitized solar cells with high efficiency.

    PubMed

    Dong, Zhenghong; Lai, Xiaoyong; Halpert, Jonathan E; Yang, Nailiang; Yi, Luoxin; Zhai, Jin; Wang, Dan; Tang, Zhiyong; Jiang, Lei

    2012-02-21

    A series of multishelled ZnO hollow microspheres with controlled shell number and inter-shell spacing have been successfully prepared by a simple carbonaceous microsphere templating method, whose large surface area and complex multishelled hollow structure enable them load sufficient dyes and multi-reflect the light for enhancing light harvesting and realize a high conversion efficiency of up to 5.6% when used in dye-sensitized solar cells. PMID:22266874

  7. Wurtzite copper-zinc-tin sulfide as a superior counter electrode material for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Kong, Jun; Zhou, Zheng-Ji; Li, Mei; Zhou, Wen-Hui; Yuan, Sheng-Jie; Yao, Rong-Yue; Zhao, Yang; Wu, Si-Xin

    2013-11-01

    Wurtzite and kesterite Cu2ZnSnS4 (CZTS) nanocrystals were employed as counter electrode (CE) materials for dye-sensitized solar cells (DSSCs). Compared to kesterite CZTS, the wurtzite CZTS exhibited higher electrocatalytic activity for catalyzing reduction of iodide electrolyte and better conductivity. Accordingly, the DSSC with wurtzite CZTS CE generated higher power conversion efficiency (6.89%) than that of Pt (6.23%) and kesterite CZTS (4.89%) CEs.

  8. Fabrication, characterization of two nano-composite CuO-ZnO working electrodes for dye-sensitized solar cell.

    PubMed

    Habibi, Mohammad Hossein; Karimi, Bahareh; Zendehdel, Mahmoud; Habibi, Mehdi

    2013-12-01

    Two kind of CuO-ZnO nanocomposite working electrodes were synthesized by sol-gel technology and applied in dye-sensitized solar cells (DSSCs). Their characteristics were studied by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD) and UV-Vis diffuse reflectance spectrum (DRS). CuO-ZnO nanocomposite thin films were prepared doctor blade technique on the fluorine-doped tin oxide (FTO) and used as working electrodes in dye sensitized solar cells (DSSC). Their photovoltaic behavior were compared with standard using D35 dye and an electrolyte containing [Co(bpy)3](PF6)2, [Co(pby)3](PF6)3, LiClO4, and 4-tert-butylpyridine (TBP). The ranges of short-circuit current (JSC) from 0.18 to 0.21 (mA/cm(2)), open-circuit voltage (VOC) from 0.24 to 0.55V, and fill factor from 0.34 to 0.39 were obtained for the DSSCs made using the working electrodes. The efficiency of the working electrodes after the addition of TBL was more than doubled. The light scattering and carrier transport properties of these composites promote the performance of dye-sensitized solar cells (DSSCs). PMID:23973582

  9. Improve photovoltaic performance of titanium dioxide nanorods based dye-sensitized solar cells by Ca-doping

    SciTech Connect

    Li, Weixin; Yang, Junyou Zhang, Jiaqi; Gao, Sheng; Luo, Yubo; Liu, Ming

    2014-09-15

    Highlights: • TiO{sub 2} nanorods doped with Ca ions were synthesized by one-step hydrothermal method. • The flat band edge of rutile TiO{sub 2} shifted positively via Ca-doping. • The photoelectric conversion efficiency of dye-sensitized solar cells (DSSCs) based on TiO{sub 2} electrode was much enhanced by Ca-doping. • A relatively high open circuit voltage was obtained by adopting Ca-doped TiO{sub 2} nanorods electrode. - Abstract: Ca-doped TiO{sub 2} nanorod arrays were prepared via the one-step hydrothermal method successfully, and the effect of Ca ions content on the photovoltaic conversion efficiency of dye-sensitized solar cells has been fully discussed in the paper. Although no obvious change on the microstructure and morphology was observed by field emission scanning electron microscope and transmission electron microscope for the Ca-doped samples, the results of X-ray diffraction and X-ray photoelectron spectroscopy confirmed that Ti{sup 4+} was substituted with Ca{sup 2+} successfully. UV–vis spectroscopy results revealed that the flat band edge shifted positively by Ca ions doping. The photovoltaic conversion efficiency of the dye-sensitized solar cells based on the 2 mol% Ca-doped TiO{sub 2} electrode was 43% higher than that of the undoped one due to the less recombination possibility.

  10. Catalytic Improvement on Counter Electrode of Dye-Sensitized Solar Cells Using Electrospun Pt Nano-Fibers.

    PubMed

    Seol, Hyunwoong; Shiratani, Masaharu; Seneekatima, Kannanut; Pornprasertsuk, Rojana

    2016-04-01

    A dye-sensitized solar cell is one of cost-competitive photovoltaic devices. For higher performance, all components have been actively studied and improved. However, Pt is still a dominant catalyst since first development although some catalytic materials were studied so far. Catalytic materials of counter electrode play an important role in the performance because it supplies electrons from counter electrode to electrolyte. Therefore, the catalytic activation of counter electrode is closely connected with the performance enhancement. In this work, Pt nano-fiber was fabricated by electrospinning and applied for the counter electrode. Its wide surface area is advantageous for good conductivity and catalytic activation. Morphological characteristics of nano-fibers were analyzed according to electrospinning conditions. Photovoltaic properties, cyclic voltammetry, impedance analysis verified the catalytic activation. Consequently, dye-sensitized solar cell with Pt nano-fiber electrospun at 5.0 kV of applied voltage had higher performance than conventional dye-sensitized solar cell with Pt thin film. This work is significant for related researches because all nano-fibers counter electrode material proposed so far never exceeded the performance of conventional Pt counter electrode. PMID:27451627

  11. Monolithic multiscale bilayer inverse opal electrodes for dye-sensitized solar cell applications

    NASA Astrophysics Data System (ADS)

    Lee, Jung Woo; Moon, Jun Hyuk

    2015-03-01

    Multilayer structures in which the layers are both electrically and physically connected are critical to be used as high-performance electrodes for photovoltaic devices. We present the first multiscale bilayer inverse opal (IO) structures for application as electrodes in dye-sensitized solar cells (DSCs). A bilayer of a mesoscopic IO layer (70 nm pore diameter) and a top macroporous IO layer (215 nm and 250 nm pore diameters) was fabricated as the high-specific-area electrode and the light-harvesting enhancing layer, respectively. The mesoscopic IO layer exhibits a dye-adsorption density, which is approximately 4 times greater than that of the macroporous IO structure because of its small pore size. The macroporous IO layer exhibits a photonic bandgap reflection in the visible-light wavelength range. We incorporated the bilayer IO electrodes into DSCs and compared the effects of the pore sizes of the macroporous layers on the photocurrent densities of the DSCs. We observed that the bilayer IO electrode DSCs that contained a 250 nm IO layer exhibited photocurrent densities greater than those of 215 nm IO DSCs. This enhanced photocurrent density was achieved because the photonic bandgap (PBG) reflection wavelength matches the wavelength range in which the N719 dye has a small light-absorption coefficient. The fabrication of this structurally homogeneous IO bilayer allows a strong contact between the layers, and the resulting bilayer, therefore, exhibits a high photovoltaic performance. We believe that this bilayer structure provides an alternative approach to the development of optimized electrode structures for various devices.Multilayer structures in which the layers are both electrically and physically connected are critical to be used as high-performance electrodes for photovoltaic devices. We present the first multiscale bilayer inverse opal (IO) structures for application as electrodes in dye-sensitized solar cells (DSCs). A bilayer of a mesoscopic IO layer (70

  12. Porphyrin Dye-Sensitized Zinc Oxide Aggregated Anodes for Use in Solar Cells.

    PubMed

    Syu, Yu-Kai; Tingare, Yogesh; Lin, Shou-Yen; Yeh, Chen-Yu; Wu, Jih-Jen

    2016-01-01

    Porphyrin YD2-o-C8-based dyes were employed to sensitize room-temperature (RT) chemical-assembled ZnO aggregated anodes for use in dye-sensitized solar cells (DSSCs). To reduce the acidity of the YD2-o-C8 dye solution, the proton in the carboxyl group of a porphyrin dye was replaced with tetrabuthyl ammonium (TBA⁺) in this work. The short-circuit current density (Jsc) of the YD2-o-C8-TBA-sensitized ZnO DSSCs is higher than that of the YD2-o-C8-sensitized cells, resulting in the improvement of the efficiency of the YD2-o-C8-based ZnO DSSCs. With an appropriate incorporation of chenodeoxycholic acid (CDCA) as coadsorbate, the Jsc and efficiency of the YD2-o-C8-TBA-sensitized ZnO DSSC are enhanced due to the improvement of the incident-photon-to-current efficiency (IPCE) values in the wavelength range of 400-450 nm. Moreover, a considerable increase in Jsc is achieved by the addition of a light scattering layer in the YD2-o-C8-TBA-sensitized ZnO photoanodes. Significant IPCE enhancement in the range 475-600 nm is not attainable by tuning the YD2-o-C8-TBA sensitization processes for the anodes without light scattering layers. Using the RT chemical-assembled ZnO aggregated anode with a light scattering layer, an efficiency of 3.43% was achieved in the YD2-o-C8-TBA-sensitized ZnO DSSC. PMID:27527136

  13. Organic dopant added polyvinylidene fluoride based solid polymer electrolytes for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Senthil, R. A.; Theerthagiri, J.; Madhavan, J.

    2016-02-01

    The effect of phenothiazine (PTZ) as dopant on PVDF/KI/I2 electrolyte was studied for the fabrication of efficient dye-sensitized solar cell (DSSC). The different weight percentage (wt%) ratios (0, 20, 30, 40 and 50%) of PTZ doped PVDF/KI/I2 electrolyte films were prepared by solution casting method using DMF as a solvent. The following techniques such as Fourier transform infrared (FT-IR), differential scanning calorimetry (DSC), X-ray diffractometer (XRD) and AC-impedance analysis have been employed to characterize the prepared polymer electrolyte films. The FT-IR studies revealed the complex formation between PVDF/KI/I2 and PTZ. The crystalline and amorphous nature of polymer electrolytes were confirmed by DSC and XRD analysis respectively. The ionic conductivities of polymer electrolyte films were calculated from the AC-impedance analysis. The undoped PVDF/KI/I2 electrolyte exhibited the ionic conductivity of 4.68×10-6 S cm-1 and this value was increased to 7.43×10-5 S cm-1 when PTZ was added to PVDF/KI/I2 electrolyte. On comparison with different wt% ratios, the maximum ionic conductivity was observed for 20% PTZ-PVDF/KI/I2 electrolyte. A DSSC assembled with the optimized wt % of PTZ doped PVDF/KI/I2 electrolyte exhibited a power conversion efficiency of 2.92%, than the undoped PVDF/KI/I2 electrolyte (1.41%) at similar conditions. Hence, the 20% PTZ-PVDF/KI/I2 electrolyte was found to be optimal for DSSC applications.

  14. Monolithic multiscale bilayer inverse opal electrodes for dye-sensitized solar cell applications.

    PubMed

    Lee, Jung Woo; Moon, Jun Hyuk

    2015-03-12

    Multilayer structures in which the layers are both electrically and physically connected are critical to be used as high-performance electrodes for photovoltaic devices. We present the first multiscale bilayer inverse opal (IO) structures for application as electrodes in dye-sensitized solar cells (DSCs). A bilayer of a mesoscopic IO layer (70 nm pore diameter) and a top macroporous IO layer (215 nm and 250 nm pore diameters) was fabricated as the high-specific-area electrode and the light-harvesting enhancing layer, respectively. The mesoscopic IO layer exhibits a dye-adsorption density, which is approximately 4 times greater than that of the macroporous IO structure because of its small pore size. The macroporous IO layer exhibits a photonic bandgap reflection in the visible-light wavelength range. We incorporated the bilayer IO electrodes into DSCs and compared the effects of the pore sizes of the macroporous layers on the photocurrent densities of the DSCs. We observed that the bilayer IO electrode DSCs that contained a 250 nm IO layer exhibited photocurrent densities greater than those of 215 nm IO DSCs. This enhanced photocurrent density was achieved because the photonic bandgap (PBG) reflection wavelength matches the wavelength range in which the N719 dye has a small light-absorption coefficient. The fabrication of this structurally homogeneous IO bilayer allows a strong contact between the layers, and the resulting bilayer, therefore, exhibits a high photovoltaic performance. We believe that this bilayer structure provides an alternative approach to the development of optimized electrode structures for various devices.

  15. Stability and efficiency of dye-sensitized solar cells based on papaya-leaf dye

    NASA Astrophysics Data System (ADS)

    Suyitno, Suyitno; Saputra, Trisma Jaya; Supriyanto, Agus; Arifin, Zainal

    2015-09-01

    The present article reports on the enhancement of the performance and stability of natural dye-based dye-sensitized solar cells (DSSCs). Natural dyes extracted from papaya leaves (PL) were investigated as sensitizers in TiO2-based DSSCs and evaluated in comparison with N719 dye. The acidity of the papaya-leaf extract dyes was tuned by adding benzoic acid. The TiO2 film-coated fluorine-doped tin oxide glass substrates were prepared using the doctor-blade method, followed by sintering at 450 °C. The counter electrode was coated by chemically deposited catalytic platinum. The working electrodes were immersed in N719 dye and papaya dye solutions with concentrations of 8 g/100 mL. The absorbance spectra of the dyes were obtained by ultra-violet-visible spectroscopy. The energy levels of the dyes were measured by the method of cyclic voltammetry. In addition, Fourier transform infrared spectroscopy was used to determine the characteristic functionalities of the dye molecules. The DSSC based on the N719 dye displayed a highest efficiency of 0.87% whereas those based on papaya-leaf dye achieved 0.28% at pH 3.5. The observed improved efficiency of the latter was attributed to the increased current density value. Furthermore, the DSSCs based on papaya-leaf dye with pH 3.5-4 exhibited better stability than those based on N719 dye. However, further studies are required to improve the current density and stability of natural dye-based DSSCs, including the investigation of alternative dye extraction routes, such as isolating the pure chlorophyll from papaya leaves and stabilizing it.

  16. Monolithic multiscale bilayer inverse opal electrodes for dye-sensitized solar cell applications.

    PubMed

    Lee, Jung Woo; Moon, Jun Hyuk

    2015-03-12

    Multilayer structures in which the layers are both electrically and physically connected are critical to be used as high-performance electrodes for photovoltaic devices. We present the first multiscale bilayer inverse opal (IO) structures for application as electrodes in dye-sensitized solar cells (DSCs). A bilayer of a mesoscopic IO layer (70 nm pore diameter) and a top macroporous IO layer (215 nm and 250 nm pore diameters) was fabricated as the high-specific-area electrode and the light-harvesting enhancing layer, respectively. The mesoscopic IO layer exhibits a dye-adsorption density, which is approximately 4 times greater than that of the macroporous IO structure because of its small pore size. The macroporous IO layer exhibits a photonic bandgap reflection in the visible-light wavelength range. We incorporated the bilayer IO electrodes into DSCs and compared the effects of the pore sizes of the macroporous layers on the photocurrent densities of the DSCs. We observed that the bilayer IO electrode DSCs that contained a 250 nm IO layer exhibited photocurrent densities greater than those of 215 nm IO DSCs. This enhanced photocurrent density was achieved because the photonic bandgap (PBG) reflection wavelength matches the wavelength range in which the N719 dye has a small light-absorption coefficient. The fabrication of this structurally homogeneous IO bilayer allows a strong contact between the layers, and the resulting bilayer, therefore, exhibits a high photovoltaic performance. We believe that this bilayer structure provides an alternative approach to the development of optimized electrode structures for various devices. PMID:25634556

  17. Nickel incorporated carbon nanotube/nanofiber composites as counter electrodes for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Joshi, Prakash; Zhou, Zhengping; Poudel, Prashant; Thapa, Amit; Wu, Xiang-Fa; Qiao, Qiquan

    2012-08-01

    A nickel incorporated carbon nanotube/nanofiber composite (Ni-CNT-CNF) was used as a low cost alternative to Pt as counter electrode (CE) for dye-sensitized solar cells (DSCs). Measurements based on energy dispersive X-rays spectroscopy (EDX) showed that the majority of the composite CE was carbon at 88.49 wt%, while the amount of Ni nanoparticles was about 11.51 wt%. Measurements based on electrochemical impedance spectroscopy (EIS) showed that the charge transfer resistance (Rct) of the Ni-CNT-CNF composite electrode was 0.71 Ω cm2, much lower than that of the Pt electrode (1.81 Ω cm2). Such a low value of Rct indicated that the Ni-CNT-CNF composite carried a higher catalytic activity than the traditional Pt CE. By mixing with CNTs and Ni nanoparticles, series resistance (Rs) of the Ni-CNT-CNF electrode was measured as 5.96 Ω cm2, which was close to the Rs of 5.77 Ω cm2 of the Pt electrode, despite the significant difference in their thicknesses: ~22 μm for Ni-CNT-CNF composite, while ~40 nm for Pt film. This indicated that use of a thick layer (tens of microns) of Ni-CNT-CNF counter electrode does not add a significant amount of resistance to the total series resistance (Rs-tot) in DSCs. The DSCs based on the Ni-CNT-CNF composite CEs yielded an efficiency of 7.96% with a short circuit current density (Jsc) of 15.83 mA cm-2, open circuit voltage (Voc) of 0.80 V, and fill factor (FF) of 0.63, which was comparable to the device based on Pt, that exhibited an efficiency of 8.32% with Jsc of 15.01 mA cm-2, Voc of 0.83, and FF of 0.67.

  18. Efficiency enhancement of cubic perovskite BaSnO3 nanostructures based dye sensitized solar cells.

    PubMed

    Rajamanickam, N; Soundarrajan, P; Vendra, Venkat K; Jasinski, Jacek B; Sunkara, Mahendra K; Ramachandran, K

    2016-03-28

    Cubic perovskite BaSnO3 (BSO) is an important photoelectron transporting material due to its electronic structure that competes with TiO2 in dye-sensitized solar cells (DSCs). Separately, BSO/TiCl4 treated and BSO/scattering layer photoelectrodes have been used in DSCs that effectively increase the photoexcited charge carriers collection resulting in superior photovoltaic performance. In the present work, the different TiCl4 treatment time (1, 3 and 5 min), different scattering layer (tetragonal anatase TiO2 and hexagonal wurtzite ZnO) and different combinations thereof are successfully used on BSO nanocuboids/nanoparticle morphological structure photoelectrodes, and then we systematically inspected their performance in DSCs. Under the optimized conditions, a power conversion efficiency (PCE) of 3.88% is obtained by a BSO/TiCl4 treated photoanode. Furthermore, the BSO photoanodes made using a scattering layer such as anatase TiO2 and hexagonal ZnO i.e., BSO/anatase TiO2 and BSO/hexagonal ZnO, exhibited PCEs of 1.14% and 1.25% respectively. In the end, one of the highest PCEs (5.68%) was achieved using BSO/TiCl4 treated/TiO2 scattering layer photoanode. Another photoelectrode such as BSO/TiCl4 treated/ZnO scattering layer exhibited a PCE of 4.28% that is also higher than the BSO/TiCl4 treated/BSO scattering layer photoanodes. Electron lifetime versus current density studies illustrate the stability of the BSO photoelectrode in DSCs. From the observed results, it is realized that BSO is one of the most important future technological materials. PMID:26935818

  19. Highly efficient dye-sensitized solar cell with GNS/MWCNT/PANI as a counter electrode

    SciTech Connect

    Al-bahrani, Majid Raissan; Xu, Xiaobao; Ahmad, Waqar; Ren, Xiaoliang; Su, Jun; Cheng, Ze; Gao, Yihua

    2014-11-15

    Highlights: • High-performance PANI/MWCNT-CE was incorporated in a Pt-CE in DSSCs. • GNS/MWCNT/PANI-CE exhibits a high power conversion efficiency (PCE) of 7.52%. • GNS/MWCNT/PANI composite has a high catalytic activity for the reduction of I{sub 3}{sup −}. • GNS/MWCNT/PANI composite has a low R{sub CT} on the electrolyte/CE interface. - Abstract: A graphene-based nanosheet composite/multiwalled carbon nanotube/polyaniline (GNS/MWCNT/PANI) was synthesized via an in situ polymerization technique and applied by the spin-coating method as a counter electrode (CE) in dye-sensitized solar cells (DSSCs). The combination of the high catalytic activity of PANI and outstanding conductivity of GNS/MWCNT improved the photovoltaic performance of the hybrid CE. The cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) showed that the GNS/MWCNT/PANI composite has high catalytic activity for the reduction of triiodide to iodide and low charge-transfer resistance at the electrolyte/electrode interface. Transmission electron microscopy (TEM) images showed that the GNS/MWCNT/PANI-CE has a rough and porous structure and X-ray diffraction analysis confirmed the formation of PANI coating on the surface of the GNS/CNT. In particular, current–voltage measurements showed the superior power conversion efficiency (PCE) of 7.52% of the DSSC based on GNS/MWCNT/PANI-CE compared to the PCE of 6.69% of the DSSC based on Pt-CE.

  20. Third row metal complexes as an alternative dye in dye sensitized solar cell system

    NASA Astrophysics Data System (ADS)

    Wahyuningsih, S.; Ramelan, A. H.; Badriyah, I.; Kristy, I. O.; Dewi, N. S.; Rahardjo, S. B.

    2013-10-01

    Copper(II), Cobalt (II) and Iron (II) complexes as photosensitizer on Dye Sensitized Solar Cell (DSSC) had been investigated. The aim of this research is to find out the respond addition of those dyes on FTO/TiO2 (FTO = fluorine Tin Oxide) thin film to visible light and the effect of various third row complexes to DSSC performance. Slip casting method was used to fabricate FTO/TiO2 and FTO/carbon thin film. The result from FTO/TiO2 UV-Vis spectra show no absorption on visible light. Dye solution was synthesized from free metal ions of Cu(II), Co(II), and Fe(II) in methanol with diphenylamine (dpa), 2,2,bypiridine (bpy), 1,10, phenathroline (phen), 4,4'-dicarboxylic acid-2,2'-bipyridine (dcbq), and anthocyanin (ant) ligands, respectively. UV-Vis spectrophotometry was used to identify FTO/TiO2/dye with various sensitizer dyes. The performance of DSSC was determined by I (current) - V (voltage) curve using Keithley 2602 A System Source. In this research, DSSCs are able to convert photon energy become electrical energy. Dye used in DSSC is greatly effect in photon to current efficiency (IPCE). The greater absorption in visible region of alternative dye used gains higher IPCE spectra. TiO2 character can help spread the absorption in whole visible region. The nanosize mesoporous TiO2 of TiO2/SiPA/CoII-PAR (SiPA = silylpropilamine) have greater value than P25 TiO2/SiPA-CoII-PAR. The SiPA/FeII-PAR and SiPA/CoII-PAR dyes are better dye than tpa.

  1. Stability and efficiency of dye-sensitized solar cells based on papaya-leaf dye.

    PubMed

    Suyitno, Suyitno; Saputra, Trisma Jaya; Supriyanto, Agus; Arifin, Zainal

    2015-09-01

    The present article reports on the enhancement of the performance and stability of natural dye-based dye-sensitized solar cells (DSSCs). Natural dyes extracted from papaya leaves (PL) were investigated as sensitizers in TiO2-based DSSCs and evaluated in comparison with N719 dye. The acidity of the papaya-leaf extract dyes was tuned by adding benzoic acid. The TiO2 film-coated fluorine-doped tin oxide glass substrates were prepared using the doctor-blade method, followed by sintering at 450 °C. The counter electrode was coated by chemically deposited catalytic platinum. The working electrodes were immersed in N719 dye and papaya dye solutions with concentrations of 8 g/100 mL. The absorbance spectra of the dyes were obtained by ultra-violet-visible spectroscopy. The energy levels of the dyes were measured by the method of cyclic voltammetry. In addition, Fourier transform infrared spectroscopy was used to determine the characteristic functionalities of the dye molecules. The DSSC based on the N719 dye displayed a highest efficiency of 0.87% whereas those based on papaya-leaf dye achieved 0.28% at pH 3.5. The observed improved efficiency of the latter was attributed to the increased current density value. Furthermore, the DSSCs based on papaya-leaf dye with pH 3.5-4 exhibited better stability than those based on N719 dye. However, further studies are required to improve the current density and stability of natural dye-based DSSCs, including the investigation of alternative dye extraction routes, such as isolating the pure chlorophyll from papaya leaves and stabilizing it. PMID:25875031

  2. ZnO@SnO2 engineered composite photoanodes for dye sensitized solar cells

    PubMed Central

    Milan, R.; Selopal, G. S.; Epifani, M.; Natile, M. M.; Sberveglieri, G.; Vomiero, A.; Concina, I.

    2015-01-01

    Layered multi-oxide concept was applied for fabrication of photoanodes for dye-sensitized solar cells based on ZnO and SnO2, capitalizing on the beneficial properties of each oxide. The effect of different combinations of ZnO@SnO2 layers was investigated, aimed at exploiting the high carrier mobility provided by the ZnO and the higher stability under UV irradiation pledged by SnO2. Bi-oxide photoanodes performed much better in terms of photoconversion efficiency (PCE) (4.96%) compared to bare SnO2 (1.20%) and ZnO (1.03%). Synergistic cooperation is effective for both open circuit voltage and photocurrent density: enhanced values were indeed recorded for the layered photoanode as compared with bare oxides (Voc enhanced from 0.39 V in case of bare SnO2 to 0.60 V and Jsc improved from 2.58 mA/cm2 pertaining to single ZnO to 14.8 mA/cm2). Improved functional performances of the layered network were ascribable to the optimization of both high chemical capacitance (provided by the SnO2) and low recombination resistance (guaranteed by ZnO) and inhibition of back electron transfer from the SnO2 conduction band to the oxidized species of the electrolyte. Compared with previously reported results, this study testifies how a simple electrode design is powerful in enhancing the functional performances of the final device. PMID:26419618

  3. Stability and efficiency of dye-sensitized solar cells based on papaya-leaf dye.

    PubMed

    Suyitno, Suyitno; Saputra, Trisma Jaya; Supriyanto, Agus; Arifin, Zainal

    2015-09-01

    The present article reports on the enhancement of the performance and stability of natural dye-based dye-sensitized solar cells (DSSCs). Natural dyes extracted from papaya leaves (PL) were investigated as sensitizers in TiO2-based DSSCs and evaluated in comparison with N719 dye. The acidity of the papaya-leaf extract dyes was tuned by adding benzoic acid. The TiO2 film-coated fluorine-doped tin oxide glass substrates were prepared using the doctor-blade method, followed by sintering at 450 °C. The counter electrode was coated by chemically deposited catalytic platinum. The working electrodes were immersed in N719 dye and papaya dye solutions with concentrations of 8 g/100 mL. The absorbance spectra of the dyes were obtained by ultra-violet-visible spectroscopy. The energy levels of the dyes were measured by the method of cyclic voltammetry. In addition, Fourier transform infrared spectroscopy was used to determine the characteristic functionalities of the dye molecules. The DSSC based on the N719 dye displayed a highest efficiency of 0.87% whereas those based on papaya-leaf dye achieved 0.28% at pH 3.5. The observed improved efficiency of the latter was attributed to the increased current density value. Furthermore, the DSSCs based on papaya-leaf dye with pH 3.5-4 exhibited better stability than those based on N719 dye. However, further studies are required to improve the current density and stability of natural dye-based DSSCs, including the investigation of alternative dye extraction routes, such as isolating the pure chlorophyll from papaya leaves and stabilizing it.

  4. Preparation and surface modification of hierarchical nanosheets-based ZnO microstructures for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Meng, Yongming; Lin, Yu; Lin, Yibing; Yang, Jiyuan

    2014-02-01

    This paper reports a simple one-step hydrothermal route for the preparation of hierarchical nanosheets-based ZnO microstructures and their application to dye-sensitized solar cells. The morphologies of the products were controlled by the dosage of the reactants. Their physical characteristics were detected by X-ray diffraction, a field-emission scanning electron microscope and a surface analyzer. It is proved that the sample of ZnO microspheres with larger surface area and stronger light-trapping capacity since the superiority of their entirely spherical structures exhibits better photoelectrochemical properties than the mixtures of ZnO microspheres and ZnO microflowers. A dye-sensitized solar cell assembled by the ZnO microspheres as photoanode shows an energy conversion efficiency of 2.94% after surface modification by tetrabutyl titanate solution at 90 °C. This result is over 1.6 times higher than the non-modified cell fabricated by the ZnO microspheres on the basis of the external improvement and the stability enhancement for the dye-sensitized ZnO photoanode.

  5. Bio-Inspired electro-photonic structure for organic and dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Lopez, Rene

    2011-03-01

    A major challenge in solar cell technology dwells in achieving an efficient absorption of photons with an effective carrier extraction. In all cases, light absorption considerations call for thicker modules while carrier transport would benefit from thinner ones. This dichotomy is a fundamental problem limiting the efficiencies of most photovoltaics. One pathway to overcome this problem is to decouple light absorption from carrier collection. We present solutions to this problem applying bio-inspired nanostructures to two different types of systems: organic photovoltaic (OPV) and dye sensitized solar cells (DSSC). For OPV devices based on poly-3-hexylthiophene:[6,6]-phenyl-C61-butyric acid methyl ester (P3HT:PCBM), we describe a 2-D photonic crystal geometry that enhances the absorption of polymer-fullerene photonic cells ~ 20 % relative to conventional planar cells. Remarkably, the photonic crystal cell offers the possibility to increase photocurrents by improvements in optical absorption and carrier extraction simultaneously, and particularly through the excitation of photonic resonant modes near the band edge of organic PV materials. We also present an optical method to extract charge transport lengths from device photoactive layers. For DSSCs we introduce a new structural motif for the photoanode in which the traditional random nanoparticle oxide network is replaced by vertically aligned bundles of oxide nanocrystals. We have used a pulsed laser deposition system to ablate titanium oxide targets to obtain the porous and vertically aligned structures for enhanced photoelectrochemical performance. Absorption studies show that in optimized structures for titanium oxide, there is a 1.4 times enhancement of surface area compared to the best sol-gel films, Incident-Photon-Conversion-Efficiency values are better than 3 times thicker sol-gel films, and ~ 92 % Absorbed-Photon-Conversion-Efficiency values have been observed when sensitizing with the N3 dye (Ru(dcbpyH)2

  6. Obviating the requirement for oxygen in SnO2-based solid-state dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Docampo, Pablo; Snaith, Henry J.

    2011-06-01

    Organic semiconductors employed in solar cells are perfectly stable to solar irradiation provided oxygen content can be kept below 1 ppm. Paradoxically, the state-of-the-art molecular hole-transporter-based solid-state dye-sensitized solar cells only operate efficiently if measured in an atmosphere containing oxygen. Without oxygen, these devices rapidly lose photovoltage and photocurrent and are rendered useless. Clearly this peculiar requirement has detrimental implications to the long term stability of these devices. Through characterizing the solar cells in air and in oxygen-free atmospheres, and considering the device architecture, we identify that direct contact between the metallic cathode and the mesoporous metal oxide photo-anode is responsible for a shunting path through the device. This metal-metal oxide contact forms a Schottky barrier under ambient conditions and the barrier is suitably high so as to prevent significant shunting of the solar cells. However, under light absorption in an anaerobic atmosphere the barrier reduces significantly, opening a low resistance shunting path which dominates the current-voltage characteristics in the solar cell. By incorporating an extra interlayer of insulating mesoporous aluminum oxide, on top of the mesoporous semiconducting metal oxide electrode, we successfully block this shunting path and subsequently the devices operate efficiently in an oxygen-free atmosphere, enabling the possibility of long term stability of solid-state dye-sensitized solar cells.

  7. Combination of optical and electrical loss analyses for a Si-phthalocyanine dye-sensitized solar cell.

    PubMed

    Lin, Keng-Chu; Wang, Lili; Doane, Tennyson; Kovalsky, Anton; Pejic, Sandra; Burda, Clemens

    2014-12-11

    In order to promote the development of solar cells with varying types of sensitizers including dyes and quantum dots, it is crucial to establish a general experimental analysis that accounts for all important optical and electrical losses resulting from interfacial phenomena. All of these varying types of solar cells share common features where a mesoporous scaffold is used as a sensitizer loading support as well as an electron transport material, which may result in light scattering. The loss of efficiency at interfaces of the sensitizer, the mesoporous TiO2 nanoparticle films, the FTO conductive layer, and the supportive glass substrate should be considered in addition to the photoinduced electron transport properties within a cell. On the basis of optical parameters, one can obtain the internal quantum efficiency (IQE) of a solar cell, an important parameter that cannot be directly measured but must be derived from several key experiments. By integrating an optical loss model with an electrical loss model, many solar cell parameters could be characterized from electro-optical observables including reflectance, transmittance, and absorptance of the dye sensitizer, the electron injection efficiency, and the charge collection efficiency. In this work, an integrated electro-optical approach has been applied to SiPc (Pc 61) dye-sensitized solar cells for evaluating the parameters affecting the overall power conversion efficiency. The absorptance results of the Pc 61 dye-sensitized solar cell provide evidence that the adsorbed Pc 61 forms noninjection layers on TiO2 surfaces when the dye immersion time exceeds 120 min, resulting in shading light from the active layer rather than an increase in photoelectric current efficiency.

  8. Combination of optical and electrical loss analyses for a Si-phthalocyanine dye-sensitized solar cell.

    PubMed

    Lin, Keng-Chu; Wang, Lili; Doane, Tennyson; Kovalsky, Anton; Pejic, Sandra; Burda, Clemens

    2014-12-11

    In order to promote the development of solar cells with varying types of sensitizers including dyes and quantum dots, it is crucial to establish a general experimental analysis that accounts for all important optical and electrical losses resulting from interfacial phenomena. All of these varying types of solar cells share common features where a mesoporous scaffold is used as a sensitizer loading support as well as an electron transport material, which may result in light scattering. The loss of efficiency at interfaces of the sensitizer, the mesoporous TiO2 nanoparticle films, the FTO conductive layer, and the supportive glass substrate should be considered in addition to the photoinduced electron transport properties within a cell. On the basis of optical parameters, one can obtain the internal quantum efficiency (IQE) of a solar cell, an important parameter that cannot be directly measured but must be derived from several key experiments. By integrating an optical loss model with an electrical loss model, many solar cell parameters could be characterized from electro-optical observables including reflectance, transmittance, and absorptance of the dye sensitizer, the electron injection efficiency, and the charge collection efficiency. In this work, an integrated electro-optical approach has been applied to SiPc (Pc 61) dye-sensitized solar cells for evaluating the parameters affecting the overall power conversion efficiency. The absorptance results of the Pc 61 dye-sensitized solar cell provide evidence that the adsorbed Pc 61 forms noninjection layers on TiO2 surfaces when the dye immersion time exceeds 120 min, resulting in shading light from the active layer rather than an increase in photoelectric current efficiency. PMID:24922464

  9. Optoelectronic and Photovoltaic Performances of Pyridine Based Monomer and Polymer Capped ZnO Dye-Sensitized Solar Cells.

    PubMed

    Singh, Satbir; Raj, Tilak; Singh, Amarpal; Kaur, Navneet

    2016-06-01

    The present research work describes the comparative analysis and performance characteristics of 4-pyridine based monomer and polymer capped ZnO dye-sensitized solar cells. The N, N-dimethyl-N4-((pyridine-4yl)methylene) propaneamine (4,monomer) and polyamine-4-pyridyl Schiff base (5, polymer) dyes were synthesized through one step condensation reaction between 4-pyridinecarboxaldehyde 1 and N, N-dimethylpropylamine 2/polyamine 3. Products obtained N, N-dimethyl-N4-((pyridine-4yl)methylene)propaneamine (4) and polyamine-4-pyridyl Schiff base (5) were purified and characterized using 1H, 13C NMR, mass, IR and CHN spectroscopy. Both the dyes 4 and 5 were further coated over ZnO nanoparticles and characterized using SEM, DLS and XRD analysis. Absorption profile and emission profile was monitored using fluorescence and UV-Vis absorption spectroscopy. A thick layer of these inbuilt dye linked ZnO nanoparticles of dyes (4) and (5) was pasted on one of the conductive side of ITO glass followed with a liquid electrolyte and counter electrode of the same conductive glass. Polyamine-4-pyridyl Schiff base polymer (5) decorated dye sensitized solar cell has shown better exciting photovoltaic properties in the form of short circuit current density (J(sc) = 6.3 mA/cm2), open circuit photo voltage (V(oc) = 0.7 V), fill factor (FF = 0.736) than monomer decorated dye sensitized solar cell. Polymer dye (5) based ZnO solar cell has shown a maximum solar power to electrical conversion efficiency of 3.25%, which is enhanced by 2.16% in case of monomer dye based ZnO solar cell under AM 1.5 sun illuminations.

  10. DFT and TD-DFT study on geometries, electronic structures and electronic absorption of some metal free dye sensitizers for dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Mohr, T.; Aroulmoji, V.; Ravindran, R. Samson; Müller, M.; Ranjitha, S.; Rajarajan, G.; Anbarasan, P. M.

    2015-01-01

    The geometries, electronic structures, polarizabilities and hyperpolarizabilities of 2-hydroxynaphthalene-1,4-dione (henna1), 3-(5-((1E)-2-(1,4-dihydro-1,4-dioxonaphthalen-3-yloxy) vinyl) thiophen-2-yl)-2-isocyanoacrylic acid (henna2) and anthocyanin dye sensitizers were studied based on density functional theory (DFT) using the hybrid functional B3LYP. The Ultraviolet-Visible (UV-Vis) spectrum was investigated by using a hybrid method which combines the properties and dynamics of many-body in the presence of time-dependent (TD) potentials, i.e. TDSCF-DFT (B3LYP). Features of the electronic absorption spectrum in the visible and near-UV regions were plotted and assigned based on TD-DFT calculations. Due to the absorption, bands of the metal-organic compound are n → π* present. The calculated results suggest that the three lowest energy excited states of the investigated dye sensitizers are due to photoinduced electron transfer processes. The interfacial electron transfer between semiconductor TiO2 electrode and dye sensitizer is owing to an electron injection process from excited dye to the semiconductor's conduction band. The role of linking the henna1 dye with a carboxylic acid via a thiophene bridge was analyzed. The results are that using a stronger π-conjugate bridge as well as a strong donator and acceptor group enhances the efficiency.

  11. "Sticky electrons" transport and interfacial transfer of electrons in the dye-sensitized solar cell.

    PubMed

    Peter, Laurence

    2009-11-17

    Dye-sensitized solar cells (DSCs, also known as Gratzel cells) mimic the photosynthetic process by using a sensitizer dye to harvest light energy to generate electrical power. Several functional features of these photochemical devices are unusual, and DSC research offers a rewarding arena in which to test new ideas, new materials, and new methodologies. Indeed, one of the most attractive chemical features of the DSC is that the basic concept can be used to construct a range of devices, replacing individual components with alternative materials. Despite two decades of increasing research activity, however, many aspects of the behavior of electrons in the DSC remain puzzling. In this Account, we highlight current understanding of the processes involved in the functioning of the DSC, with particular emphasis on what happens to the electrons in the mesoporous film following the injection step. The collection of photoinjected electrons appears to involve a random walk process in which electrons move through the network of interconnected titanium dioxide nanoparticles while undergoing frequent trapping and detrapping. During their passage to the cell contact, electrons may be lost by transfer to tri-iodide species in the redox electrolyte that permeates the mesoporous film. Competition between electron collection and back electron transfer determines the performance of a DSC: ideally, all injected electrons should be collected without loss. This Account then goes on to survey recent experimental and theoretical progress in the field, placing particular emphasis on issues that need to be resolved before we can gain a clear picture of how the DSC works. Several important questions about the behavior of "sticky" electrons, those that undergo multiple trapping and detrapping, in the DSC remain unanswered. The most fundamental of these concerns is the nature of the electron traps that appear to dominate the time-dependent photocurrent and photovoltage response of DSCs. The

  12. Pomegranate leaves and mulberry fruit as natural sensitizers for dye-sensitized solar cells

    SciTech Connect

    Chang, Ho; Lo, Yu-Jen

    2010-10-15

    This study employs chlorophyll extract from pomegranate leaf and anthocyanin extract from mulberry fruit as the natural dyes for a dye-sensitized solar cell (DSSC). A self-developed nanofluid synthesis system is employed to prepare TiO{sub 2} nanofluid with an average particle size of 25 nm. Electrophoresis deposition was performed to deposit TiO{sub 2} nanoparticles on the indium tin oxide (ITO) conductive glass, forming a TiO{sub 2} thin film with the thickness of 11 {mu}m. Furthermore, this TiO{sub 2} thin film was sintered at 450 C to enhance the thin film compactness. Sputtering was used to prepare counter electrode by depositing Pt thin film on FTO glass at a thickness of 20 nm. The electrodes, electrolyte (I{sub 3}{sup -}), and dyes were assembled into a cell module and illuminated by a light source simulating AM 1.5 with a light strength of 100 mW/cm{sup 2} to measure the photoelectric conversion efficiency of the prepared DSSCs. According to experimental results, the conversion efficiency of the DSSCs prepared by chlorophyll dyes from pomegranate leaf extract is 0.597%, with open-circuit voltage (V{sub OC}) of 0.56 V, short-circuit current density (J{sub SC}) of 2.05 mA/cm{sup 2}, and fill factor (FF) of 0.52. The conversion efficiency of the DSSCs prepared by anthocyanin dyes from mulberry extract is 0.548%, with V{sub OC} of 0.555 V and J{sub SC} of 1.89 mA/cm{sup 2} and FF of 0.53. The conversion efficiency is 0.722% for chlorophyll and anthocyanin as the dye mixture, with V{sub OC} of 0.53 V, J{sub SC} of 2.8 mA/cm{sup 2}, and FF of 0.49. (author)

  13. Dye sensitized photovoltaic miniaturized solar cells, used as optical sensors for line of sight detection

    NASA Astrophysics Data System (ADS)

    Cesar, Cortes Torres Carlos; Sampei, Kota; Miho, Ogawa; Masataka, Ozawa; Norihisa, Miki

    2014-11-01

    Dye sensitized photovoltaic devices have been studied as transparent and low-cost solar cells. Our group have miniaturized the cells and used them as transparent optical sensors. This paper reports the design and fabrication of the cells and avoids the cross talk among cells, which was found recently and such effect provokes hardware instability. We use these optical sensors as an eye tracking device. The sensor array detects the difference in the intensity of light reflected from the pupil and the sclera and then determines the pupil position. Each sensor consists of two electrodes and electrolyte; hence our device conformed by only four semi-circular shaped sensors on eyeglasses can detect the view angle in both horizontal and vertical directions. Manufacturing process gives us freedom to easily re-arrange, add or remove sensors. In our prior work we had good performance in stand-alone configuration. We used specialized equipment from National Instruments for our measurements. However we found that: A cell is not 100% independent from the others, is affected by the absence or presence of light at the neighbour cells. When our device is connected to other electronic devices (for data processing), all cells have the same voltage among them; therefore, all cells behave the same way when any of them is affected by light. The root cause is, due to all sensors were interconnected via a micro channel and filled with electrolyte, due to its conductive properties, electrolyte does neither need electrodes nor physical paths to conduct electricity, so it creates a liquid wire between sensors, hence the gap between them become inexistent, consequently when our device is connected to other electronic devices, due to this unique channel and by sharing a common electronic ground, this connection provokes the voltage to be the same among all sensors in the array. Our device becomes four separate voltage lines in a parallel circuit. The device was also in short circuit provoked

  14. Spectroscopic and photoelectrochemical studies of metal-free dyes for applications in dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Mulhern, Kacie Ryan

    In this dissertation, we present a series of novel chalcogenorhodamine dyes bearing phosphonic acids and carboxylic acids for sensitizers of nanocrystalline TiO2 in dye-sensitized solar cells (DSCs). We studied the effect of surface-attachment functionality and aggregation on the persistence, electron transfer reactivity, and overall photoelectrochemical performance of the dyes on TiO2 for DSCs. The dyes were constructed around a 3,6-bis(dimethylamino)chalcogenoxanthylium core and varied in the 9-substituent: 5-carboxythien-2-yl in dyes 1-E (E = O, Se), 2-carboxythien-3-yl in dyes 2-E (E = Se), 5-phosphonothien-2-yl in dyes 3-E (E = O, Se), 4-carboxyphenyl in dyes 4-E (E = O, S), and 4-phosphonophenyl in dyes 5-E (E = O, Se). Monolayers of 1-E, 3-E, 4-E, and 5-E on nanocrystalline TiO2 films consisted of both H-aggregated and non-aggregated dyes, whereas 2-E underwent little or no aggregation upon adsorption. With the exception of 2-E, surface coverages of dyes and the extent of H-aggregation varied minimally with surface-attachment functionality, structure of the 9-aryl group, and identity of the chalcogen heteroatom. Carboxylic acid-functionalized dyes 1-E and 4-E desorbed rapidly and completely from TiO2 into acidified CH3CN, but phosphonic acid-functionalized dyes 3-E and 5-E persisted on TiO2 for days. We used transient absorption spectroscopy to characterize excited-state electron injection from a 1-Se, 2-Se, and 3-Se to TiO2. Injection of electrons from photoexcited dyes into TiO2 yielded the dication radical (1-Se +, 2-Se+, and 3-Se +) and an associated transient absorption at wavelengths shorter than 540 nm, the amplitude of which was proportional to the quantum yield of electron injection (Qinj). Our data reveal the Qinj for H-aggregated 1-Se was approximately 2-fold greater than Q inj for non-aggregated 1-Se and approximately 3-fold greater than Qinj for non-aggregated 2-Se. Additionally, the Qinj from H-aggregated 3-Se was (2.0 +/- 1.3)-fold greater

  15. Self-assembled monolayer of graphene/Pt as counter electrode for efficient dye-sensitized solar cell.

    PubMed

    Gong, Feng; Wang, Hong; Wang, Zhong-Sheng

    2011-10-21

    Monolayer of PDDA/graphene/PDDA/H(2)PtCl(6) is fabricated on conductive glass using electrostatic layer-by-layer self-assembly technique, which is then converted to graphene/Pt monolayer for use as counter electrode in dye-sensitized solar cell (DSSC). As compared to the sputtered Pt counter electrode, the self-assembled monolayer reduces the Pt amount by about 1000-fold but exhibits comparable photovoltaic performance. This finding provides a new route to fabrication of cheap and efficient counter electrodes for flow-line production of DSSCs. PMID:21909512

  16. Enhanced performance of supported HfO2 counter electrodes for redox couples used in dye-sensitized solar cells.

    PubMed

    Yun, Sining; Pu, Haihui; Chen, Junhong; Hagfeldt, Anders; Ma, Tingli

    2014-02-01

    Mesoporous-graphitic-carbon-supported HfO2 (HfO2 -MGC) nanohybrids were synthesized by using a soft-template route. Characterization and a systematic investigation of the catalytic properties, stability, and catalytic mechanism were performed for HfO2 -MGC counter electrodes (CEs) in dye-sensitized solar cells (DSSCs). The new HfO2 -MGC as a CE in DSSCs showed a surprisingly high efficiency of 7.75 % for the triiodide/iodide redox couple and 3.69 % for the disulfide/thiolate redox couple, greater than the Pt electrode in the corresponding electrolyte system, which opens up a possibility for its practical application.

  17. A branching NiCuPt alloy counter electrode for high-efficiency dye-sensitized solar cell

    NASA Astrophysics Data System (ADS)

    Yang, Peizhi; Tang, Qunwei

    2016-01-01

    A rising objective for high-efficiency dye-sensitized solar cells (DSSCs) is to create extraordinary and cost-effective counter electrode (CE) electrocatalysts. We present here a branching NiCuPt alloy CE synthesized by electrodepositing Ni on ZnO microrod templates and subsequently growing branched Cu as well as suffering from a galvanic displacement for Pt uptake. The resultant NiCuPt alloy CE displays a promising electrocatalytic activity toward redox electrolyte having I-/I3- couples. An impressive power conversion efficiency of 9.66% is yielded for the liquid-junction DSSC platform.

  18. In situ monitoring and optimization of room temperature ultra-fast sensitization for dye-sensitized solar cells.

    PubMed

    Davies, Matthew L; Watson, Trystan M; Holliman, Peter J; Connell, Arthur; Worsley, David A

    2014-10-25

    We describe the fastest dyeing of TiO2 photo-electrodes for dye-sensitized solar cells reported to date (<2 min) at room temperature giving η = 7.5% for an N719-SQ1-CDCA mixture which is significantly higher than devices dyed for >12 h using the same dye mixture (η = 5.5%). Time-lapse photography has been used to monitor the ultra-fast co-sensitization. The data show significantly different dye uptake between passive and pump dyeing reflecting competitive sorption between a Ru complex (N719) and an organic dye (SQ1).

  19. Decatungstate acid improves the photo-induced electron lifetime and retards the recombination in dye sensitized solar cells.

    PubMed

    Li, Liang; Yang, Yulin; Fan, Ruiqing; Liu, Jian; Jiang, Yanxia; Yang, Bin; Cao, Wenwu

    2016-10-14

    Decatungstate acid (DA) was utilized to modify TiO2 in the photoanode of dye sensitized solar cells. The photo-induced electron lifetime was evidently improved and the recombination was greatly inhibited. DA can introduce levels of impurities and lower the Fermi level through a doping effect and thus increase the photocurrent. Moreover, the improved charge carrier density can be found through external electric field surface photovoltage and Mott-Schottky plots. A 22.94% enhancement in photocurrent was achieved with little degradation in photovoltage, leading to a 10.28% increase in optic-to-electric power conversion efficiency. PMID:27550800

  20. Enhanced efficiency of the dye-sensitized solar cells by excimer laser irradiated carbon nanotube network counter electrode

    SciTech Connect

    Chien, Yun-San Fu, Wei-En; Yang, Po-Yu; Lee, I-Che; Chu, Chih-Chieh; Chou, Chia-Hsin; Cheng, Huang-Chung

    2014-02-03

    The carbon nanotube network decorated with Pt nanoparticles (PtCNT) irradiated by excimer laser as counter electrode (CE) of dye-sensitized solar cells (DSSCs) has been systematically demonstrated. The conversion efficiency would be improved from 7.12% to 9.28% with respect to conventional Pt-film one. It was attributed to the enhanced catalytic surface from Pt nanoparticles and the improved conductivity due to the adjoining phenomenon of PtCNTs irradiated by laser. Moreover, the laser annealing could also promote the interface contact between CE and conductive glass. Therefore, such a simple laser-irradiated PtCNT network is promising for the future flexible DSSCs applications.

  1. Graphene nanoplatelets doped with N at its edges as metal-free cathodes for organic dye-sensitized solar cells.

    PubMed

    Ju, Myung Jong; Jeon, In-Yup; Kim, Jae Cheon; Lim, Kimin; Choi, Hyun-Jung; Jung, Sun-Min; Choi, In Taek; Eom, Yu Kyung; Kwon, Young Jin; Ko, Jaejung; Lee, Jae-Joon; Kim, Hwan Kyu; Baek, Jong-Beom

    2014-05-21

    Challenging precious Pt-based electrocatalysts for dye-sensitized solar cells (DSSCs), graphene nanoplatelets that are N-doped at the edges (NGnPs) are prepared via simply ball-milling graphite in the presence of nitrogen gas. DSSCs based on specific nanoplatelets designated "NGnP5" display superior photovoltaic performance (power conversion efficiency, 10.27%) compared to that of conventional Pt-based devices (9.96%). More importantly, the NGnP counter electrode exhibits outstanding electrochemical stability and electrocatalytic activity with a cobalt-complex redox couple.

  2. High-temperature annealing of TiO2 nanotube membranes for efficient dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Mohammadpour, Fatemeh; Altomare, Marco; So, Seulgi; Lee, Kiyoung; Mokhtar, Mohamed; Alshehri, Abdelmohsen; Al-Thabaiti, Shaeel A.; Schmuki, Patrik

    2016-01-01

    We fabricate photo-anodes by transferring anodic TiO2 nanotube membranes in tube-top-down configuration on FTO glass, and use them for constructing frontside illuminated dye-sensitized solar cells. Prior to solar cell construction, the tube-based photo-anodes are crystallized at different temperatures (400-800 °C), and the effects of tube electron transport properties on the photovoltaic performance of the solar cells are investigated. We show that improved solar cell efficiencies (up to ca. 8.0%) can be reached by high-temperature treatment of the tube membranes. Consistent with electron transport time measurements, remarkably enhanced electron mobility is enabled when tube membranes are crystallized at 600 °C.

  3. Geometrical and energetical structural changes in organic dyes for dye-sensitized solar cells probed using photoelectron spectroscopy and DFT.

    PubMed

    Eriksson, Susanna K; Josefsson, Ida; Ellis, Hanna; Amat, Anna; Pastore, Mariachiara; Oscarsson, Johan; Lindblad, Rebecka; Eriksson, Anna I K; Johansson, Erik M J; Boschloo, Gerrit; Hagfeldt, Anders; Fantacci, Simona; Odelius, Michael; Rensmo, Håkan

    2016-01-01

    The effects of alkoxy chain length in triarylamine based donor-acceptor organic dyes are investigated with respect to the electronic and molecular surface structures on the performance of solar cells and the electron lifetime. The dyes were investigated when adsorbed on TiO2 in a configuration that can be used for dye-sensitized solar cells (DSCs). Specifically, the two dyes D35 and D45 were compared using photoelectron spectroscopy (PES) and density functional theory (DFT) calculations. The differences in solar cell characteristics when longer alkoxy chains are introduced in the dye donor unit are attributed to geometrical changes in dye packing while only minor differences were observed in the electronic structure. A higher dye load was observed for D45 on TiO2. However, D35 based solar cells result in higher photocurrent although the dye load is lower. This is explained by different geometrical structures of the dyes on the surface.

  4. Mesoporous junctions and nanocrystalline solar cells

    NASA Astrophysics Data System (ADS)

    Graetzel, Michael

    2000-03-01

    Learning from the concepts used by green plants, we have developed a molecular photovoltaic system based on the sensitization of nanocrystalline TiO2 films. In analogy to photosyntesis, light is absorbed by a monolayer of dye attached to the surface of a wide-band-gap oxide. The mesoporous morphology of the layer provides a substrate characterized by a very large surface area. The roughness factor of a 10-micron thick film reaches easily 1000. Light penetrating the dye loaded TiO2 nanocrystals is therefore collected in an efficient manner, similar to the thylakoid vesicles in green leafs which are stacked in order to enhance solar light harvesting. The excited dye injects an electron in the conduction band of the oxide resulting in efficient and very rapid charge separation. Nearly quantitative conversion of photons in electric current have been achieved with these devices over the whole visible and near-IR range of the spectrum. The overall AM 1.5 solar-to electric power conversion efficiency has reached already 11unravel the dynamics of interfacial charge transfer reactions at these dye- sensitized heterojunctions.

  5. Improved conversion efficiency of dye sensitized solar cell using Zn doped TiO2-ZrO2 nanocomposite

    NASA Astrophysics Data System (ADS)

    Tomar, Laxmi J.; Bhatt, Piyush J.; Desai, Rahul K.; Chakrabarty, B. S.; Panchal, C. J.

    2016-05-01

    TiO2-ZrO2 and Zn doped TiO2-ZrO2 nanocomposites were prepared by hydrothermal method for dye sensitized solar cell (DSSC) application. The structural and optical properties were investigated by X -ray diffraction (XRD) and UV-Visible spectroscopy respectively. XRD results revealed the formation of material in nano size. The average crystallite size is 22.32 nm, 17.41 nm and 6.31 nm for TiO2, TiO2-ZrO2 and Zn doped TiO2-ZrO2 nanocomposites respectively. The optical bandgap varies from 2.04 eV to 3.75 eV. Dye sensitized solar cells were fabricated using the prepared material. Pomegranate juice was used as a sensitizer and graphite coated conducting glass plate was used as counter electrode. The I - V characteristics were recorded to measure photo response of DSSC. Photovoltaic parameter like open circuit voltage, power conversion efficiency, and fill factor were evaluated for fabricated solar cell. The power conversion efficiency of DSSC fabricated with TiO2, TiO2-ZrO2 and Zn doped TiO2-ZrO2 nanocomposites were found 0.71%, 1.97% and 4.58% respectively.

  6. Self-assembled molecular p/n junctions for applications in dye-sensitized solar energy conversion.

    PubMed

    Farnum, Byron H; Wee, Kyung-Ryang; Meyer, Thomas J

    2016-09-01

    The achievement of long-lived photoinduced redox separation lifetimes has long been a central goal of molecular-based solar energy conversion strategies. The longer the redox-separation lifetime, the more time available for useful work to be extracted from the absorbed photon energy. Here we describe a novel strategy for dye-sensitized solar energy applications in which redox-separated lifetimes on the order of milliseconds to seconds can be achieved based on a simple toolkit of molecular components. Specifically, molecular chromophores (C), electron acceptors (A) and electron donors (D) were self-assembled on the surfaces of mesoporous, transparent conducting indium tin oxide nanoparticle (nanoITO) electrodes to prepare both photoanode (nanoITO|-A-C-D) and photocathode (nanoITO|-D-C-A) assemblies. Nanosecond transient-absorption and steady-state photolysis measurements show that the electrodes function microscopically as molecular analogues of semiconductor p/n junctions. These results point to a new chemical strategy for dye-sensitized solar energy conversion based on molecular excited states and electron acceptors/donors on the surfaces of transparent conducting oxide nanoparticle electrodes. PMID:27554411

  7. Self-assembled molecular p/n junctions for applications in dye-sensitized solar energy conversion.

    PubMed

    Farnum, Byron H; Wee, Kyung-Ryang; Meyer, Thomas J

    2016-09-01

    The achievement of long-lived photoinduced redox separation lifetimes has long been a central goal of molecular-based solar energy conversion strategies. The longer the redox-separation lifetime, the more time available for useful work to be extracted from the absorbed photon energy. Here we describe a novel strategy for dye-sensitized solar energy applications in which redox-separated lifetimes on the order of milliseconds to seconds can be achieved based on a simple toolkit of molecular components. Specifically, molecular chromophores (C), electron acceptors (A) and electron donors (D) were self-assembled on the surfaces of mesoporous, transparent conducting indium tin oxide nanoparticle (nanoITO) electrodes to prepare both photoanode (nanoITO|-A-C-D) and photocathode (nanoITO|-D-C-A) assemblies. Nanosecond transient-absorption and steady-state photolysis measurements show that the electrodes function microscopically as molecular analogues of semiconductor p/n junctions. These results point to a new chemical strategy for dye-sensitized solar energy conversion based on molecular excited states and electron acceptors/donors on the surfaces of transparent conducting oxide nanoparticle electrodes.

  8. Natural dye extract of lawsonia inermis seed as photo sensitizer for titanium dioxide based dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Ananth, S.; Vivek, P.; Arumanayagam, T.; Murugakoothan, P.

    2014-07-01

    Natural dye extract of lawsonia inermis seed were used as photo sensitizer to fabricate titanium dioxide nanoparticles based dye sensitized solar cells. Pure titanium dioxide (TiO2) nanoparticles in anatase phase were synthesized by sol-gel technique and pre dye treated TiO2 nanoparticles were synthesized using modified sol-gel technique by mixing lawsone pigment rich natural dye during the synthesis itself. This pre dye treatment with natural dye has yielded colored TiO2 nanoparticles with uniform adsorption of natural dye, reduced agglomeration, less dye aggregation and improved morphology. The pure and pre dye treated TiO2 nanoparticles were subjected to structural, optical, spectral and morphological studies. Dye sensitized solar cells (DSSC) fabricated using the pre dye treated and pure TiO2 nanoparticles sensitized by natural dye extract of lawsonia inermis seed showed a promising solar light to electron conversion efficiency of 1.47% and 1% respectively. The pre dye treated TiO2 based DSSC showed an improved efficiency of 47% when compared to that of conventional DSSC.

  9. Natural dye extract of lawsonia inermis seed as photo sensitizer for titanium dioxide based dye sensitized solar cells.

    PubMed

    Ananth, S; Vivek, P; Arumanayagam, T; Murugakoothan, P

    2014-07-15

    Natural dye extract of lawsonia inermis seed were used as photo sensitizer to fabricate titanium dioxide nanoparticles based dye sensitized solar cells. Pure titanium dioxide (TiO2) nanoparticles in anatase phase were synthesized by sol-gel technique and pre dye treated TiO2 nanoparticles were synthesized using modified sol-gel technique by mixing lawsone pigment rich natural dye during the synthesis itself. This pre dye treatment with natural dye has yielded colored TiO2 nanoparticles with uniform adsorption of natural dye, reduced agglomeration, less dye aggregation and improved morphology. The pure and pre dye treated TiO2 nanoparticles were subjected to structural, optical, spectral and morphological studies. Dye sensitized solar cells (DSSC) fabricated using the pre dye treated and pure TiO2 nanoparticles sensitized by natural dye extract of lawsonia inermis seed showed a promising solar light to electron conversion efficiency of 1.47% and 1% respectively. The pre dye treated TiO2 based DSSC showed an improved efficiency of 47% when compared to that of conventional DSSC.

  10. Self-assembled molecular p/n junctions for applications in dye-sensitized solar energy conversion

    NASA Astrophysics Data System (ADS)

    Farnum, Byron H.; Wee, Kyung-Ryang; Meyer, Thomas J.

    2016-09-01

    The achievement of long-lived photoinduced redox separation lifetimes has long been a central goal of molecular-based solar energy conversion strategies. The longer the redox-separation lifetime, the more time available for useful work to be extracted from the absorbed photon energy. Here we describe a novel strategy for dye-sensitized solar energy applications in which redox-separated lifetimes on the order of milliseconds to seconds can be achieved based on a simple toolkit of molecular components. Specifically, molecular chromophores (C), electron acceptors (A) and electron donors (D) were self-assembled on the surfaces of mesoporous, transparent conducting indium tin oxide nanoparticle (nanoITO) electrodes to prepare both photoanode (nanoITO|-A-C-D) and photocathode (nanoITO|-D-C-A) assemblies. Nanosecond transient-absorption and steady-state photolysis measurements show that the electrodes function microscopically as molecular analogues of semiconductor p/n junctions. These results point to a new chemical strategy for dye-sensitized solar energy conversion based on molecular excited states and electron acceptors/donors on the surfaces of transparent conducting oxide nanoparticle electrodes.

  11. Self-assembled molecular p/n junctions for applications in dye-sensitized solar energy conversion

    NASA Astrophysics Data System (ADS)

    Farnum, Byron H.; Wee, Kyung-Ryang; Meyer, Thomas J.

    2016-09-01

    The achievement of long-lived photoinduced redox separation lifetimes has long been a central goal of molecular-based solar energy conversion strategies. The longer the redox-separation lifetime, the more time available for useful work to be extracted from the absorbed photon energy. Here we describe a novel strategy for dye-sensitized solar energy applications in which redox-separated lifetimes on the order of milliseconds to seconds can be achieved based on a simple toolkit of molecular components. Specifically, molecular chromophores (C), electron acceptors (A) and electron donors (D) were self-assembled on the surfaces of mesoporous, transparent conducting indium tin oxide nanoparticle (nanoITO) electrodes to prepare both photoanode (nanoITO|–A–C–D) and photocathode (nanoITO|–D–C–A) assemblies. Nanosecond transient-absorption and steady-state photolysis measurements show that the electrodes function microscopically as molecular analogues of semiconductor p/n junctions. These results point to a new chemical strategy for dye-sensitized solar energy conversion based on molecular excited states and electron acceptors/donors on the surfaces of transparent conducting oxide nanoparticle electrodes.

  12. Fe(II)-Polypyridines as Chromophores in Dye-Sensitized Solar Cells: A Computational Perspective.

    PubMed

    Jakubikova, Elena; Bowman, David N

    2015-05-19

    Over the past two decades, dye-sensitized solar cells (DSSCs) have become a viable and relatively cheap alternative to conventional crystalline silicon-based systems. At the heart of a DSSC is a wide band gap semiconductor, typically a TiO2 nanoparticle network, sensitized with a visible light absorbing chromophore. Ru(II)-polypyridines are often utilized as chromophores thanks to their chemical stability, long-lived metal-to-ligand charge transfer (MLCT) excited states, tunable redox potentials, and near perfect quantum efficiency of interfacial electron transfer (IET) into TiO2. More recently, coordination compounds based on first row transition metals, such as Fe(II)-polypyridines, gained some attention as potential sensitizers in DSSCs due to their low cost and abundance. While such complexes can in principle sensitize TiO2, they do so very inefficiently since their photoactive MLCT states undergo intersystem crossing (ISC) into low-lying metal-centered states on a subpicosecond time scale. Competition between the ultrafast ISC events and IET upon initial excitation of Fe(II)-polypyridines is the main obstacle to their utilization in DSSCs. Suitability of Fe(II)-polypyridines to serve as sensitizers could therefore be improved by adjusting relative rates of the ISC and IET processes, with the goal of making the IET more competitive with ISC. Our research program in computational inorganic chemistry utilizes a variety of tools based on density functional theory (DFT), time-dependent density functional theory (TD-DFT) and quantum dynamics to investigate structure-property relationships in Fe(II)-polypyridines, specifically focusing on their function as chromophores. One of the difficult problems is the accurate determination of energy differences between electronic states with various spin multiplicities (i.e., (1)A, (1,3)MLCT, (3)T, (5)T) in the ISC cascade. We have shown that DFT is capable of predicting the trends in the energy ordering of these electronic

  13. Solar hydrogen production by tandem cell system composed of metal oxide semiconductor film photoelectrode and dye-sensitized solar cell

    NASA Astrophysics Data System (ADS)

    Arakawa, H.; Shiraishi, C.; Tatemoto, M.; Kishida, H.; Usui, D.; Suma, A.; Takamisawa, A.; Yamaguchi, T.

    2007-09-01

    Photocatalytic and photoelectrochemical approaches to solar hydrogen production in our group were introduced. In photocatalytic water splitting system using NiO x/ TiO II powder photocatalyst with concentrated Na IICO 3 aqueous solution, solar energy conversion efficiency to H II and O II production (STH efficiency) was 0.016%. In addition, STH efficiency of visible light responding photocatalyst, NiOx/ promoted In 0.9Ni 0.1TaO 4, was estimated at 0.03%. In photoelectrochemical system using an oxide semiconductor film phptoelectrode, STH efficiencies of meosporous TiO II (Anatase) , mesoporous visible light responding S-doped TiO II (Anatase) and WO 3 film were 0.32-0.44% at applied potential of 0.35 V vs NHE, 0.14% at 0.55 V and 0.44% at 0.9 V, respectively. Finally, solar hydrogen production by tandem cell system composed of an oxide semiconductor photoelectrode, a Pt wire counter electrode and a dye-sensitized solar cell (DSC) was investigated. As photoelectrodes, meosporous TiO II (Anatase), mesoporous S-doped TiO II (Anatase), WO 3, BiVO 4 and Fe IIO 3 film were tested. STH efficiency of tandem cell system composed of a WO 3 film photoelectrode, and a two-series-connected DSC (Voc = 1.4 V) was 2.5-2.8%. In conclusion, it is speculated that more than 5% STH efficiency will be obtained by tandem cell system composed of an oxide semiconductor photoelectrode and a two-series-connected DSC in near future. This suggests a cost-effective and practical application of this system for solar hydrogen production.

  14. Quasi-solid electrolyte with polyamidoamine dendron modified-talc applied to dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Andrade, Marcos A. S.; Nogueira, Ana F.; Miettunen, Kati; Tiihonen, Armi; Lund, Peter D.; Pastore, Heloise O.

    2016-09-01

    A sequence of generations of polyamidoamine dendron modified-talc, PAMAM-talc-Gn (n = 1, 3, 5 and 7), is proposed as additive in a composite gel electrolyte for dye-sensitized solar cells. Polyiodides are intercalated into the organotalc interlamellar space by adsorption of iodine vapor, producing triiodide and polyiodides. We investigate the effect of organotalc content on the charge transport in the electrolyte and solar cell performance and optimize the organotalc content. Without the previous adsorption of iodine molecules, the organotalcs appear to remove iodine from the electrolyte solution decreasing device's performance significantly. Instead, the samples with additional iodide had higher Jsc and efficiency approaching the values of the reference cells containing liquid, which suggests that this kind of gelling method would be suitable for dye solar cells. Charge transport in the gel electrolyte is investigated with electrochemical impedance spectroscopy and cyclic voltammetry analyses using symmetrical CE-CE electrochemical cells.

  15. Surfactant free most probable TiO2 nanostructures via hydrothermal and its dye sensitized solar cell properties

    PubMed Central

    Mali, Sawanta S.; Kim, Hyungjin; Shim, Chang Su; Patil, Pramod S.; Kim, Jin Hyeok; Hong, Chang Kook

    2013-01-01

    Tailoring the nano-morphology and nano-architecture of titanium dioxide (TiO2) is the most important task in the third generation solar cells (Dye sensitized solar cells/Quantum dot sensitized solar cells) (DSSCs/QDSSCs). In this article we present complete study of surfactant free synthesis of TiO2 nanostructures by a simple and promising hydrothermal route. The plethora of nanostructures like nanoparticles clusters, 1D tetragonal nanorods, 3D dendrites containing nanorods having <30 nm diameter and 3D hollow urchin like have been synthesized. These nanostructures possess effective large surface area and thus useful in DSSCs. In the present work, 7.16% power conversion efficiency has been demonstrated for 3D dendritic hollow urchin like morphology. Our synthetic strategy provides an effective solution for surfactant free synthesis of efficient TiO2 nanoarchitectures. PMID:24141599

  16. Enhanced Conversion Efficiencies in Dye-Sensitized Solar Cells Achieved through Self-Assembled Platinum(II) Metallacages

    NASA Astrophysics Data System (ADS)

    He, Zuoli; Hou, Zhiqiang; Xing, Yonglei; Liu, Xiaobin; Yin, Xingtian; Que, Meidan; Shao, Jinyou; Que, Wenxiu; Stang, Peter J.

    2016-07-01

    Two-component self-assembly supramolecular coordination complexes with particular photo-physical property, wherein unique donors are combined with a single metal acceptor, can be utilized for many applications including in photo-devices. In this communication, we described the synthesis and characterization of two-component self-assembly supramolecular coordination complexes (SCCs) bearing triazine and porphyrin faces with promising light-harvesting properties. These complexes were obtained from the self-assembly of a 90° Pt(II) acceptor with 2,4,6-tris(4-pyridyl)-1,3,5-triazine (TPyT) or 5,10,15,20-Tetra(4-pyridyl)-21H,23H-porphine (TPyP). The greatly improved conversion efficiencies of the dye-sensitized TiO2 solar cells were 6.79 and 6.08 respectively, while these SCCs were introduced into the TiO2 nanoparticle film photoanodes. In addition, the open circuit voltage (Voc) of dye-sensitized solar cells was also increased to 0.769 and 0.768 V, which could be ascribed to the inhibited interfacial charge recombination due to the addition of SCCs.

  17. Enhanced power conversion efficiency of dye-sensitized solar cells using nanoparticle/nanotube double layered film.

    PubMed

    Sun, Kyung Chul; Yun, Sung Hoon; Yoon, Chang Hyun; Ko, Hwan Ho; Yi, Sung; Jeong, Sung Hoon

    2013-12-01

    To enhance the power conversion efficiency of dye-sensitized solar cell, a new type of double layered photoanode was prepared using TiO2 nanoparticle in under layer and TiO2 nanotube in upper layer. TiO2 nanotubes were synthesized by hydrothermal polymerization. The morphology and the properties were investigated and characterized by Field Emission-Scanning Electron Microscopy (FE-SEM), Field Emission-Transmission Electron Microscopy (FE-TEM), Wide Angle X-ray Diffraction (WAXD), Thermogravimetric analysis (TGA) and, Brunauer-Emmett-Teller test (BET). The light-to-electricity conversion efficiency was improved with the double-layered TiO2 film, which in turn, significantly increases the power conversion efficiency of dye-sensitized solar cells (DSSCs). This is due to large dye adsorption of light-scatters as well as TiO2 main layer. Moreover, rapid electron transport and light-havesting efficiency contributed to high conversion efficiency. The power conversion efficiency of an optimized cell (photoanode consisting of 13-15 microm main-layer and TNT over-layer) was 8.06% under simulated Air mass 1.5 (AM 1.5) global sunlight (1 Sun, 100 mW/cm2).

  18. Enhancing the efficiency of flexible dye-sensitized solar cells utilizing natural dye extracted from Azadirachta indica

    NASA Astrophysics Data System (ADS)

    Sahare, Sanjay; Veldurthi, Naresh; Singh, Ranbir; Swarnkar, A. K.; Salunkhe, Manauti; Bhave, Tejashree

    2015-10-01

    The natural dye extracted from Azadirechta indica (neem) was used as a sensitizer in flexible dye-sensitized solar cells (DSSCs). The fabricated DSSC exhibited open circuit voltage of 0.538 V with 2.81% power conversion efficiency (η) in back-illuminated mode which is higher than that reported in the literature. In order to understand the characteristics of DSSC, systematic study of solar cell component materials was carried out. Anatase TiO2 (30-40 nm) nanoparticles were synthesized by DC arc plasma method and deposited electrophoretically on a flexible titanium (Ti) substrate. A platinum-coated polyethylene terephthalate (PET) substrate was used as a counter electrode to construct flexible DSSC. The structural and optical behavior of neem-dye sensitized TiO2 thin film has been studied using x-ray diffraction, field emission scanning electron microscopy, high resolution transmission electron microscopy and UV-visible spectroscopy. We have observed that the neem dye gives a very good sensitization effect. In addition, the dye has good prospects as a low-cost and environmental friendly alternative to ruthenium-based sensitizers which are normally used in DSSCs.

  19. Retarded hydrolysis-condensing reactivity of tetrabutyl titanate by acetylacetone and the application in dye-sensitized solar cells

    SciTech Connect

    Zhou, Conghua Ouyang, Jun; Yang, Bingchu

    2013-10-15

    Graphical abstract: - Highlights: • Effect of acetone acetyl on coarsening rate of TiO{sub 2} nanocrystallites was studied. • Hydrolysis reactivity of alkoxide was retarded with addition of acetone acetyl. • Coarsening rate of TiO{sub 2} nanocrystallites is retarded with addition of acetone acetyl. • The synthesized TiO{sub 2} sols were utilized in dye sensitized solar cells. • Small particles formed by Ti-complexes were beneficial for device performance. - Abstract: TiO{sub 2} nanocrystallites have been synthesized by hydrothermal reaction using tetrabutyl titanate as source material. Acetylacetone was utilized to modify hydrolysis-condensation behavior of the alkoxide and thus coarsening dynamics of TiO{sub 2} nanocrystallites in the reaction. With assistance of Fourier transformation infrared spectrum, transmission electron microscopy, selected area electron diffraction and X-ray diffraction, interaction between acetylacetone and tetrabutyltitanate was explored, crystallographic and morphological properties of TiO{sub 2} nanocrystallites were monitored. Less hydrolysable complex was formed by “method of chelating” as tetrabutyltitanate was mixed with acetylacetone, leading to retarded coarsening rate of nanocrystallites. The obtained TiO{sub 2} nanocrystallites were applied to fabricate nanoporous photoanode of dye sensitized solar cells. Improvement of 18% has been achieved for photo-to-electric energy conversion efficiency of the devices due to both upgraded open circuit voltage and photocurrent density.

  20. Development of dye-sensitized solar cells based on naturally extracted dye from the maqui berry (Aristotelia chilensis)

    NASA Astrophysics Data System (ADS)

    Leyrer, Julio; Hunter, Renato; Rubilar, Monica; Pavez, Boris; Morales, Eduardo; Torres, Simont

    2016-10-01

    The mini modules of dye-sensitized solar cells (DSSCs) were investigated for their conversion efficiency using anthocyanin-enriched extracts from maqui berry, which to date has never been tested in a DSSC. Anthocyanins are a group of red, purple, violet and blue water-soluble polyphenolic pigments widely found in berry fruits. Maqui berries are a particularly rich source. The aqueous extract concentrations of maqui fruit were tested at 750 and 1500 mg of anthocyanin/L. The immersion time to produce sensitized TiO2 film was 8 h. According to the experimental results, the conversion efficiency of the DSSC prepared with 750 mg of anthocyanin/L was 0.14%, with an open-circuit voltage (VOC) of 0.43 V, a short-circuit current density (JSC) of 0.38 mA/cm2, and a fill factor (FF) of 0.450. The conversion efficiency attained with 1500 mg of anthocyanin/L was 0.19%, with (VOC) of 0.45 V, (JSC) of 0.44 mA/cm2 and FF of 0.55. Therefore, a higher concentration brought about a higher photosensitized performance. The maqui extracts were successfully dye sensitized over a layer of TiO2 nanoparticles, providing useful information for further studies related to the use of natural pigments as sensitizers for solar cells.

  1. Theoretical insight on novel donor-acceptor exTTF-based dyes for dye-sensitized solar cells.

    PubMed

    Calbo, Joaquín; Viruela, Pedro M; Ortí, Enrique

    2014-04-01

    A thorough density functional theory study is performed for the three carboxyl-based derivatives of the exTTF-TCF chromophore, where the π-extended tetrathiafulvalene (exTTF) electron-donor is linked to the tricyanofuran (TCF) electron-acceptor through an ethylene bridge, as dyes for dye-sensitized solar cells. Calculations predict that the carboxyl group in the acceptor moiety adopts an adequate orientation for an efficient anchoring on the semiconductor TiO₂ surface. The carboxylic acid group holds a negative charge twice larger than the cyano moiety that favors the electron injection to the semiconductor. Time-dependent calculations allow for the assignment of the absorption bands in the UV-vis spectrum of exTTF-TCF and confirm the presence of two low-lying charge-transfer electronic transitions that account for the moderately-intense absorption in the 450-800 nm range. The striking optical absorption properties of exTTF-TCF are preserved for the carboxylic analogues. Finally, periodic calculations show relevant topological differences between the carboxylic derivatives anchored on the TiO₂ surface, which would notably influence in the power conversion efficiency of a dye-sensitized solar cell. PMID:24643466

  2. Know thy nano neighbor. Plasmonic versus electron charging effects of metal nanoparticles in dye-sensitized solar cells.

    PubMed

    Choi, Hyunbong; Chen, Wei Ta; Kamat, Prashant V

    2012-05-22

    Neighboring metal nanoparticles influence photovoltaic and photocatalytic behavior of semiconductor nanostructures either through Fermi level equilibration by accepting electrons or inducing localized surface plasmon effects. By employing SiO(2)- and TiO(2)-capped Au nanoparticles we have identified the mechanism with which the performance of dye-sensitized solar cells (DSSC) is influenced by the neighboring metal nanoparticles. The efficiency of an N719 dye-sensitized solar cell (9.3%) increased to 10.2% upon incorporation of 0.7% Au@SiO(2) and to 9.8% upon loading of 0.7% Au@TiO(2) nanoparticles. The plasmonic effect as monitored by introducing Au@SiO(2) in DSSC produces higher photocurrent. However, Au nanoparticles undergo charge equilibration with TiO(2) nanoparticles and shift the apparent Fermi level of the composite to more negative potentials. As a result, Au@TiO(2) nanoparticle-embedded DSSC exhibit higher photovoltage. A better understanding of these two effects is crucial in exploiting the beneficial aspects of metal nanoparticles in photovoltaics.

  3. Enhanced Conversion Efficiencies in Dye-Sensitized Solar Cells Achieved through Self-Assembled Platinum(II) Metallacages

    PubMed Central

    He, Zuoli; Hou, Zhiqiang; Xing, Yonglei; Liu, Xiaobin; Yin, Xingtian; Que, Meidan; Shao, Jinyou; Que, Wenxiu; Stang, Peter J.

    2016-01-01

    Two-component self-assembly supramolecular coordination complexes with particular photo-physical property, wherein unique donors are combined with a single metal acceptor, can be utilized for many applications including in photo-devices. In this communication, we described the synthesis and characterization of two-component self-assembly supramolecular coordination complexes (SCCs) bearing triazine and porphyrin faces with promising light-harvesting properties. These complexes were obtained from the self-assembly of a 90° Pt(II) acceptor with 2,4,6-tris(4-pyridyl)-1,3,5-triazine (TPyT) or 5,10,15,20-Tetra(4-pyridyl)-21H,23H-porphine (TPyP). The greatly improved conversion efficiencies of the dye-sensitized TiO2 solar cells were 6.79 and 6.08 respectively, while these SCCs were introduced into the TiO2 nanoparticle film photoanodes. In addition, the open circuit voltage (Voc) of dye-sensitized solar cells was also increased to 0.769 and 0.768 V, which could be ascribed to the inhibited interfacial charge recombination due to the addition of SCCs. PMID:27404912

  4. Mechanisms of electron transport and recombination in ZnO nanostructures for dye-sensitized solar cells.

    PubMed

    Vega-Poot, Alberto G; Macías-Montero, Manuel; Idígoras, Jesus; Borrás, Ana; Barranco, Angel; Gonzalez-Elipe, Agustín R; Lizama-Tzec, Francisco I; Oskam, Gerko; Anta, Juan A

    2014-04-14

    ZnO is an attractive material for applications in dye-sensitized solar cells and related devices. This material has excellent electron-transport properties in the bulk but its electron diffusion coefficient is much smaller in mesoporous films. In this work the electron-transport properties of two different kinds of dye-sensitized ZnO nanostructures are investigated by small-perturbation electrochemical techniques. For nanoparticulate ZnO photoanodes prepared via a wet-chemistry technique, the diffusion coefficient is found to reproduce the typical behavior predicted by the multiple-trapping and the hopping models, with an exponential increase with respect to the applied bias. In contrast, in ZnO nanostructured thin films of controlled texture and crystallinity prepared via a plasma chemical vapor deposition method, the diffusion coefficient is found to be independent of the electrochemical bias. This observation suggests a different transport mechanism not controlled by trapping and electron accumulation. In spite of the quite different transport features, the recombination kinetics, the electron-collection efficiency and the photoconversion efficiency are very similar for both kinds of photoanodes, an observation that indicates that surface properties rather than electron transport is the main efficiency-determining factor in solar cells based on ZnO nanostructured photoanodes.

  5. One-step process for the synthesis and deposition of anatase, two-dimensional, disk-shaped TiO₂ for dye-sensitized solar cells.

    PubMed

    Lee, Chang Soo; Kim, Jin Kyu; Lim, Jung Yup; Kim, Jong Hak

    2014-12-10

    We report a one-step process for the synthesis and deposition of anatase, two-dimensional (2D), disk-shaped TiO2 (DS-TiO2) using titanium isopropoxide (TTIP), ethyl cellulose (EC), and solvents. The planar structure of EC plays a pivotal role as the sacrificing template to generate the 2D disk-shaped structure with a thickness of 1.5-3.5 μm, while a disk-like structure was well developed in the tetrahydrofuran (THF)/toluene mixed solvent. The quasi-solid-state dye-sensitized solar cells (qssDSSCs), fabricated with a nanogel electrolyte and a DS-TiO2 layer on a nanocrystalline (NC)-TiO2 photoanode, showed an energy conversion efficiency of 5.0% without any TiCl4 post-treatment, which is higher than that fabricated without DS-TiO2 (4.2%). When utilizing a poly((1-(4-ethenylphenyl)methyl)-3-butyl-imidazolium iodide) (PEBII) as the solid electrolyte, a high efficiency of 6.6% was achieved due to the combination of high mobility PEBII and a bifunctional DS-TiO2 layer with a 2D structure and anatase phase. The bifunctionality of the DS-TiO2 layer allows greater light scattering back into the device and provides additional surface area for improved dye adsorption, resulting in short circuit current density (Jsc). PMID:25397581

  6. Worm-like mesoporous TiO2 thin films templated using comb copolymer for dye-sensitized solar cells with polymer electrolyte

    NASA Astrophysics Data System (ADS)

    Lee, Jae Hun; Park, Cheol Hun; Jung, Jung Pyo; Kim, Jong Hak

    2015-12-01

    A comb copolymer consisting of hydrophobic poly(2-[3-(2H-benzotriazol-2-yl)-4-hydroxyphenyl] ethyl methacrylate) (PBEM) and hydrophilic poly(oxyethylene methacrylate) (POEM) is synthesized via one-pot free radical polymerization. The PBEM-POEM comb copolymer is used as an agent to direct the structure toward one consisting of worm-like mesoporous TiO2 (WM-TiO2) films. The selective, preferential interaction between the titania precursor and the hydrophilic POEM chains is responsible for the formation of a well-organized worm-like mesostructure. The morphology of the WM-TiO2 films is characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). In particular, the effects of film thickness on the optical and electrochemical properties are systematically investigated. The introduction of the WM-TiO2 layer between the nanocrystalline TiO2 (NC-TiO2) layer and fluorine-doped tin oxide (FTO) glass results in increased transmittance of visible light due to an antireflective property, decreased interfacial resistance and suppressed charge recombination at the interfaces of NC-TiO2/FTO glass. As a result, the photovoltaic conversion efficiency of the dye-sensitized solar cell (DSSC) with a polymer electrolyte is improved from 5.3% to 6.6% at an optimum film thickness (310 nm). The obtained efficiency represents a higher efficiency for the N719-based DSSC with a solvent-free, polymer electrolyte.

  7. Preparation of TiO2 nanowires/nanotubes using polycarbonate membranes and their uses in dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Roh, Dong Kyu; Patel, Rajkumar; Ahn, Sung Hoon; Kim, Dong Jun; Kim, Jong Hak

    2011-10-01

    Track-etched polycarbonate (PC) membranes were used as a soft template to synthesize mesoporous TiO2 for use in dye-sensitized solar cells (DSSCs). The Ti precursor infiltrated into the cylindrical confined spaces of PC membranes. Upon calcination at 500 °C, TiO2 nanowires (15TNW) were obtained from PC with a 15 nm pore diameter, whereas TiO2 nanotubes (50TNT and 100TNT) were generated from PC with 50 and 100 nm diameter pores, respectively. TNW and TNT were used as photoelectrodes in DSSCs employing a polymer electrolyte. The ranking of the cell efficiencies of the 200 nm thick TiO2 films was 50TNT (1.1%) > 15TNW (0.8%) ≅ 100TNT (0.7%), which was mostly attributed to different amounts of dye adsorption due to different surface areas. These TNW and TNT films were further coated with the graft copolymer-directed mesoporous TiO2 and were used as interfacial layers between the FTO glass and the 4 μm thick nanocrystalline TiO2 film. As a result, the order of energy conversion efficiency was 15TNW (5.0%) ≅ 50TNT (4.8%) > 100TNT (4.1%). The improved performance of 15TNW was due to a higher transmittance through the electrode and a longer electron lifetime for recombination. The DSSC performance was systematically investigated in terms of interfacial resistance and charge recombination using electrochemical impedance spectroscopy.

  8. Effect of Electron-Electron Interaction on Transport in Dye-Sensitized Nanocrystalline TiO2

    SciTech Connect

    van de Lagemaat, J.; Kopidakis, N.; Neale, N. R.; Frank, A. J.

    2005-01-01

    Experimental measurements and continuous-time random walk simulations on sensitized electrolyte-infused porous nanocrystalline TiO2 films show that the actual electronic charge in the films is significantly larger than that estimated from small-perturbation methods by a constant, light-intensity-independent factor. This observation can be explained by small-perturbation techniques measuring the chemical diffusion coefficient of electrons instead of the normally assumed tracer diffusion coefficient of electrons. The difference between the two diffusion coefficients is attributed to the presence of an exponential density of states through which electrons interact. At high light intensities, an additional extra component owing to Coulomb interactions between the electrons is expected to arise.

  9. Design of hybrid nanoheterostructure systems for enhanced quantum and solar conversion efficiencies in dye-sensitized solar cells

    SciTech Connect

    Kılıç, Bayram E-mail: kbayramkilic@gmail.com; Telli, Hakan; Başaran, Ali; Pirge, Gursev; Tüzemen, Sebahattin

    2015-04-07

    Dye sensitized solar cells (DSSCs) with an innovative design involving controlled-morphology vertically aligned (VA) ZnO nanowires within mesoporous TiO{sub 2} structures with ultrahigh surface area for implementation as photoanodes are herein reported. Although TiO{sub 2} nanostructures exhibit excellent power conversion efficiency, the electron transport rate is low owing to low electron mobility. To overcome this, ZnO nanowires with high electron mobility have been investigated as potential candidates for photoanodes. However, the power conversion efficiency of ZnO nanowires is still lower than that of TiO{sub 2} owing to their low internal surface area. Consequently, in this work, vertical growth of ZnO nanowires within mesoporous TiO{sub 2} structures is carried out to increase their solar power conversion efficiency. The photovoltaic performance of solar cells using ZnO nanowires, mesoporous TiO{sub 2}, and TiO{sub 2}/ZnO hybrid structures are compared. The VA TiO{sub 2}/ZnO hybrid structures are found to provide direct electron transfer compared with the tortuous pathway of zero-dimensional nanostructures, resulting in an increased conversion efficiency. It is demonstrated that the light scattering of the photoanode film is increased and electron recombination is decreased when an appropriate amount of mesoporous TiO{sub 2} is used as a substrate for ZnO nanowires. The DSSC fabricated with the TiO{sub 2}/ZnO hybrid photoanode prepared with 15.8 wt. % TiO{sub 2} showed the highest conversion efficiency of 7.30%, approximately 5%, 18%, and 40% higher than that of DSSCs fabricated with 3.99 wt. % TiO{sub 2}, pure TiO{sub 2}, and pure ZnO photoanodes, respectively.

  10. Design of hybrid nanoheterostructure systems for enhanced quantum and solar conversion efficiencies in dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Kılıç, Bayram; Telli, Hakan; Tüzemen, Sebahattin; Başaran, Ali; Pirge, Gursev

    2015-04-01

    Dye sensitized solar cells (DSSCs) with an innovative design involving controlled-morphology vertically aligned (VA) ZnO nanowires within mesoporous TiO2 structures with ultrahigh surface area for implementation as photoanodes are herein reported. Although TiO2 nanostructures exhibit excellent power conversion efficiency, the electron transport rate is low owing to low electron mobility. To overcome this, ZnO nanowires with high electron mobility have been investigated as potential candidates for photoanodes. However, the power conversion efficiency of ZnO nanowires is still lower than that of TiO2 owing to their low internal surface area. Consequently, in this work, vertical growth of ZnO nanowires within mesoporous TiO2 structures is carried out to increase their solar power conversion efficiency. The photovoltaic performance of solar cells using ZnO nanowires, mesoporous TiO2, and TiO2/ZnO hybrid structures are compared. The VA TiO2/ZnO hybrid structures are found to provide direct electron transfer compared with the tortuous pathway of zero-dimensional nanostructures, resulting in an increased conversion efficiency. It is demonstrated that the light scattering of the photoanode film is increased and electron recombination is decreased when an appropriate amount of mesoporous TiO2 is used as a substrate for ZnO nanowires. The DSSC fabricated with the TiO2/ZnO hybrid photoanode prepared with 15.8 wt. % TiO2 showed the highest conversion efficiency of 7.30%, approximately 5%, 18%, and 40% higher than that of DSSCs fabricated with 3.99 wt. % TiO2, pure TiO2, and pure ZnO photoanodes, respectively.

  11. Scattering-layer-induced energy storage function in polymer-based quasi-solid-state dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Zhang, Xi; Jiang, Hongrui

    2015-03-01

    Photo-self-charging cells (PSCs) are compact devices with dual functions of photoelectric conversion and energy storage. By introducing a scattering layer in polymer-based quasi-solid-state dye-sensitized solar cells, two-electrode PSCs with highly compact structure were obtained. The charge storage function stems from the formed ion channel network in the scattering layer/polymer electrolyte system. Both the photoelectric conversion and the energy storage functions are integrated in only the photoelectrode of such PSCs. This design of PSC could continuously output power as a solar cell with considerable efficiency after being photo-charged. Such PSCs could be applied in highly-compact mini power devices.

  12. Photovoltaic performance of dye-sensitized solar cells using TiO2 nanotubes aggregates produced by hydrothermal synthesis

    NASA Astrophysics Data System (ADS)

    Chen, Qiufan; Sun, Xiaonan; Liu, Anping; Zhang, Qifeng; Cao, Guozhong; Zhou, Xiaoyuan

    2015-09-01

    This paper reports the synthesis, detailed structural characterization of aggregated TiO2 nanotubes and the application of such aggregated TiO2 nanotubes as photoelectrodes in solar cells (dye sensitized DSCs). A maximum overall conversion efficiency of 7.9% has been achieved, which use conventional dyes without any additional chemical treatments under circumstances of an open-circuit voltage of 710 mV, a short-circuit current density of 16.8mA/cm2, and a fill factor of 66%. This impressive performance is believed to attribute to the micron-sized aggregate structure which may be favorable for light harvesting, the desired high specific surface area and pure anatase phase for dye absorption. This significant improvement in the conversion efficiency indicates that DSCs based on aggregated TiO2 nanotubes are a promising alternative to semiconductor-based solar cells.

  13. Dye-sensitized solar cell with natural gel polymer electrolytes and f-MWCNT as counter-electrode

    NASA Astrophysics Data System (ADS)

    Nwanya, A. C.; Amaechi, C. I.; Ekwealor, A. B. C.; Osuji, R. U.; Maaza, M.; Ezema, F. I.

    2015-05-01

    Samples of DSSCs were made with gel polymer electrolytes using agar, gelatin and DNA as the polymer hosts. Anthocyanine dye from Hildegardia barteri flower is used to sensitize the TiO2 electrode, and the spectrum of the dye indicates strong absorptions in the blue region of the solar spectrum. The XRD pattern of the TiO2 shows that the adsorption of the dye did not affect the crystallinity of the electrode. The f-MWCNT indicates graphite structure of the MWCNTs were acid oxidized without significant damage. Efficiencies of 3.38 and 0.1% were obtained using gelatin and DNA gel polymer electrolytes, respectively, for the fabricated dye-sensitized solar cells.

  14. Improving scattering layer through mixture of nanoporous spheres and nanoparticles in ZnO-based dye-sensitized solar cells

    PubMed Central

    2014-01-01

    A scattering layer is utilized by mixing nanoporous spheres and nanoparticles in ZnO-based dye-sensitized solar cells. Hundred-nanometer-sized ZnO spheres consisting of approximately 35-nm-sized nanoparticles provide not only effective light scattering but also a large surface area. Furthermore, ZnO nanoparticles are added to the scattering layer to facilitate charge transport and increase the surface area as filling up large voids. The mixed scattering layer of nanoparticles and nanoporous spheres on top of the nanoparticle-based electrode (bilayer geometry) improves solar cell efficiency by enhancing both the short-circuit current (Jsc) and fill factor (FF), compared to the layer consisting of only nanoparticles or nanoporous spheres. PMID:24982606

  15. Cost-effective, transparent iron selenide nanoporous alloy counter electrode for bifacial dye-sensitized solar cell

    NASA Astrophysics Data System (ADS)

    Liu, Juan; Tang, Qunwei; He, Benlin; Yu, Liangmin

    2015-05-01

    Pursuit of cost-effective and efficient counter electrodes (CEs) is a persistent objective for dye-sensitized solar cells (DSSCs). We present here the design of transparent Fe-Se nanoporous alloy CEs for bifacial DSSC applications. Due to the superior charge-transfer ability for I-/I3- redox couples, electrocatalytic reduction toward I3- species, and optical transparency in visible-light region, the bifacial DSSC with FeSe alloy electrode yields maximum front and rear efficiencies of 9.16% and 5.38%, respectively. A fast start-up, high multiple start capability, and good stability of the FeSe alloy CE demonstrate the potential applications in driving solar panels. The impressive efficiency along with simple preparation of the cost-effective Fe-Se nanoporous alloy CEs highlights their potential application in robust bifacial DSSCs.

  16. Influence of sodium cations of N3 dye on the photovoltaic performance and stability of dye-sensitized solar cells.

    PubMed

    Andrade, Luísa; Zakeeruddin, Shaik M; Nazeeruddin, Mohammad K; Ribeiro, Helena Aguilar; Mendes, Adélio; Grätzel, Michael

    2009-05-11

    We report on the effect of substituting the two tetrabutyl ammonium counter ions of the standard N719 dye by sodium ions on the performance and stability of dye-sensitized solar cells (DSCs). The disodium analogue of N719 in conjunction with a non-volatile electrolyte gives a conversion efficiency of 7.6% under standard global AM 1.5 sunlight. Devices maintain 99% of their initial performance after 1000 h under full sunlight aging at 50 degrees C. Electrochemical impedance spectroscopy and photovoltage transient decay studies reveal the evolution of the solar cell parameters during aging. Remarkably, upon aging a decrease in the rate of electron back reaction with the triiodide ions across the TiO(2)/electrolyte interface appears as well as enhanced electronic conduction in the TiO(2) film.

  17. Optical description of solid-state dye-sensitized solar cells. I. Measurement of layer optical properties

    SciTech Connect

    Moule, Adam J.; Snaith, Henry J.; Kaiser, Markus; Klesper, Heike; Meerholz, Klaus; Huang, David M.; Graetzel, Michael

    2009-10-01

    The efficiency of a photovoltaic device is limited by the portion of solar energy that can be captured. We discuss how to measure the optical properties of the various layers in solid-state dye-sensitized solar cells (SDSC). We use spectroscopic ellipsometry to determine the complex refractive index of each of the various layers in a SDSC. Each of the ellipsometry fits is used to calculate a transmission spectrum that is compared to a measured transmission spectrum. The complexities of pore filling on the fitting of the ellipsometric data are discussed. Scanning electron microscopy and energy dispersive x-ray spectroscopy is shown to be an effective method for determining pore filling in SDSC layers. Accurate effective medium optical constants for each layer are presented and the material limits under which these optical constants can be used are discussed.

  18. Preparation of Nanoporous TiO2 for Dye-Sensitized Solar Cell (DSSC) Using Various Dyes

    NASA Astrophysics Data System (ADS)

    Yuliarto, Brian; Fanani, Fahiem; Fuadi, M. Kasyful; Nugraha

    2010-10-01

    This article reports the development of organic dyes as an attempt to reduce material costs of Dye-Sensitized Solar Cell (DSSC). Indonesia, a country with variety and considerable number of botanical resources, is suitable to perform the research. Indonesian black rice, curcuma, papaya leaf, and the combination were chosen as organic dyes source. Dyes were extracted using organic solvent and adsorbed on mesoporous Titanium Dioxide (TiO2) which has been optimized in our laboratory. The best dyes light absorbance and performance obtained from papaya leaf as chlorophyll dyes that gives two peaks at 432 nm and 664 nm from UV-Vis Spectrophotometry and performance under 100 mW/cm2 Xenon light solar simulator gives VOC = 0.566 Volt, JSC = 0.24 mA/cm2, Fill Factor = 0.33, and efficiency of energy conversion 0,045%.

  19. High-bendability flexible dye-sensitized solar cell with a nanoparticle-modified ZnO-nanowire electrode

    NASA Astrophysics Data System (ADS)

    Jiang, C. Y.; Sun, X. W.; Tan, K. W.; Lo, G. Q.; Kyaw, A. K. K.; Kwong, D. L.

    2008-04-01

    We report a high-bendability flexible dye-sensitized solar cell (DSSC) based on a ZnO-nanowire photoelectrode, which was fabricated on polyethylene terephtalate/indium tin oxide substrate by low-temperature hydrothermal growth. Nanowire morphology shows preferable in crack resistance due to its efficient release of bending stress. The ZnO-nanowire film can be bended to an extreme radius of 2mm with no crack observed. Flexible DSSCs based on this kind of ZnO-nanowire photoelectrodes showed good bending stability. With a ZnO-nanoparticle modification on the nanowires, the flexible DSSC fabricated showed a much improved power conversion efficiency. Meanwhile, the good bendablility of this nanoparticle-modified nanowire electrode is maintained. The results demonstrate that high quality ZnO nanowires fabricated by the low-temperature method is promising for efficient and flexible plastic solar cells.

  20. Characteristics of SnO2 nanofiber/TiO2 nanoparticle composite for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Gong, Jiawei; Qiao, Hui; Sigdel, Sudhan; Elbohy, Hytham; Adhikari, Nirmal; Zhou, Zhengping; Sumathy, K.; Wei, Qufu; Qiao, Qiquan

    2015-06-01

    SnO2 nanofibers and their composites based photoanodes were fabricated and investigated in the application of dye-sensitized solar cells. The photoanode made of SnO2/TiO2 composites yielded an over 2-fold improvement in overall conversion efficiency. The microstructure of SnO2 nanofibers was characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). A compact morphology of composites was observed using scanning electron microscopy (SEM). A long charge diffusion length (62.42 μm) in the composites was derived from time constant in transient photovoltage and photocurrent analysis. These experimental results demonstrate that one-dimensional nanostructured SnO2/TiO2 composites have a great potential for application in solar cells.

  1. A dye-sensitized solar cell based on platinum nanotube counter electrode with efficiency of 9.05%

    NASA Astrophysics Data System (ADS)

    Wu, Jihuai; Tang, Ziying; Huang, Yunfang; Huang, Miaoliang; Yu, Haijun; Lin, Jianming

    2014-07-01

    Platinum nanotubes (PNTs) are directly grown on fluorine-doped tin oxide substrates by a facile polycarbonate template method. Morphology observation and electrochemical measurements indicate that the PNTs show a one-dimensional structure, lower charge-transfer resistance, larger exchange current density and higher electrocatalytic activity for iodide/triiodide redox reaction. Using the PNT as counter electrode and MgO as block layer on TiO2 film, the fabricated dye-sensitized solar cell achieves a light-to-electric energy conversion efficiency of 9.05% under a simulated solar light irradiation of 100 mW cm-2, the efficiency is increased by 25.5% compared to that of DSSC based on conventional Pt counter electrode. Higher efficiency for the PNT electrode is due its one-dimensional nanostructure, large surface area and good electrochemical activity to iodide/triiodide couple.

  2. Electrodeposited nanoporous versus nanoparticulate ZnO films of similar roughness for dye-sensitized solar cell applications.

    PubMed

    Guerin, V M; Magne, C; Pauporté, Th; Le Bahers, T; Rathousky, J

    2010-12-01

    We present a comparative study of two different ZnO porous film morphologies for dye-sensitized solar cell (DSSC) fabrications. Nanoparticulate ZnO was prepared by the doctor-blade technique starting from a paste containing ZnO nanoparticles. Nanoporous ZnO films were grown by a soft template-assisted electrochemical growth technique. The film thicknesses were adjusted at similar roughness of about 300 in order to permit a worthy comparison. The effects on the cell performances of sensitization by dyes belonging to three different families, namely, xanthene (eosin Y) and indoline (D102, D131, D149 and D205) organic dyes as well as a ruthenium polypyridine complex (N719), have been investigated. The mesoporous electrodeposited matrix exhibits significant morphological changes upon the photoanode preparation, especially upon the dye sensitization, that yield to a dramatic change of the inner layer morphology and increase in the layer internal specific surface area. In the case of indoline dyes, better efficiencies were found with the electrodeposited ZnO porous matrixes compared to the nanoparticulate ones, in spite of significantly shorter electron lifetimes measured by impedance spectroscopy. The observation is interpreted in terms of much shorter transfer time in the oxide in the case of the electrodeposited ZnO films. Among the tested dyes, the D149 and D205 indoline organic dyes with a strong acceptor group were found the most efficient with the best cell over 4.6% of overall conversion efficiency.

  3. Screening π-conjugated bridges of organic dyes for dye-sensitized solar cells with panchromatic visible light harvesting

    NASA Astrophysics Data System (ADS)

    Yang, Zhenqing; Liu, Chunmeng; Shao, Changjin; Zeng, Xiaofei; Cao, Dapeng

    2016-07-01

    Developing highly efficient organic dyes with panchromatic visible light harvesting for dye-sensitized solar cells (DSSCs) is still one of the most important scientific challenges. Here, we design a series of phenothiazine derivative organic dyes with donor-π-acceptor (D-π-A) structure using density functional theory (DFT) and time-dependent DFT (TDDFT) based on experimentally synthesized typical SH-6 organic dyes. Results indicate that the newly designed BUCT13 - BUCT30 dyes show smaller HOMO-LUMO energy gaps, higher molar extinction coefficients and obvious redshifts compared to the SH-6 dye, and the maximum absorption peaks of eight dyes are greater than 650 nm among the newly designed dyes. In particular, BUCT27 exhibits a 234 nm redshift and the maximum molar extinction coefficient with an increment of about 80% compared to the SH-6 dye. BUCT19 exhibits not only a 269 nm redshift and higher molar extinction coefficient with an increment of about 50% compared to the SH-6 dye, but the extremely broad absorption spectrum covering the entire visible range up to the near-IR region of 1200 nm. It is expected that this work can provide a new strategy and guidance for the investigation of these dye-sensitized devices.

  4. Screening π-conjugated bridges of organic dyes for dye-sensitized solar cells with panchromatic visible light harvesting.

    PubMed

    Yang, Zhenqing; Liu, Chunmeng; Shao, Changjin; Zeng, Xiaofei; Cao, Dapeng

    2016-07-01

    Developing highly efficient organic dyes with panchromatic visible light harvesting for dye-sensitized solar cells (DSSCs) is still one of the most important scientific challenges. Here, we design a series of phenothiazine derivative organic dyes with donor-π-acceptor (D-π-A) structure using density functional theory (DFT) and time-dependent DFT (TDDFT) based on experimentally synthesized typical SH-6 organic dyes. Results indicate that the newly designed BUCT13 - BUCT30 dyes show smaller HOMO-LUMO energy gaps, higher molar extinction coefficients and obvious redshifts compared to the SH-6 dye, and the maximum absorption peaks of eight dyes are greater than 650 nm among the newly designed dyes. In particular, BUCT27 exhibits a 234 nm redshift and the maximum molar extinction coefficient with an increment of about 80% compared to the SH-6 dye. BUCT19 exhibits not only a 269 nm redshift and higher molar extinction coefficient with an increment of about 50% compared to the SH-6 dye, but the extremely broad absorption spectrum covering the entire visible range up to the near-IR region of 1200 nm. It is expected that this work can provide a new strategy and guidance for the investigation of these dye-sensitized devices. PMID:27188528

  5. Controllable preparation of TiO2 nanowire arrays on titanium mesh for flexible dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Liu, Wenwu; Lu, Hui; Zhang, Mei; Guo, Min

    2015-08-01

    TiO2 nanowire arrays (NWAs) with an average diameter of 80 nm have been successfully synthesized on titanium (Ti) mesh substrates via hydrothermal method. The effects of preparing conditions such as concentration of NaOH solution, reaction time, and hydrothermal temperature on the growth of TiO2 nanoarrays and its related photovoltaic properties were systematically investigated by scanning electron microscopy, X-ray diffraction, and photovoltaic properties test. The growth mechanism of the Ti mesh-supported TiO2 nanostructures was discussed in detail. Moreover, a parametric study was performed to determine the optimized temperature and time of the dye sensitized process for the flexible dye-sensitized solar cell (DSSC). It is demonstrated that hydrothermal parameters had obvious influence on the morphology and growth density of the as-prepared TiO2 nanoarrays. In addition, the performance of the flexible DSSC depended strongly on the sensitization temperature and time. By utilizing Ti mesh-supported TiO2 NWAs (with a length of about 14 μm) as a photoanode, the flexible DSSC with a short circuit current density of 10.49 mA cm-2, an open-circuit voltage of 0.69 V, and an overall power conversion efficiency of 3.42% was achieved.

  6. Screening π-conjugated bridges of organic dyes for dye-sensitized solar cells with panchromatic visible light harvesting.

    PubMed

    Yang, Zhenqing; Liu, Chunmeng; Shao, Changjin; Zeng, Xiaofei; Cao, Dapeng

    2016-07-01

    Developing highly efficient organic dyes with panchromatic visible light harvesting for dye-sensitized solar cells (DSSCs) is still one of the most important scientific challenges. Here, we design a series of phenothiazine derivative organic dyes with donor-π-acceptor (D-π-A) structure using density functional theory (DFT) and time-dependent DFT (TDDFT) based on experimentally synthesized typical SH-6 organic dyes. Results indicate that the newly designed BUCT13 - BUCT30 dyes show smaller HOMO-LUMO energy gaps, higher molar extinction coefficients and obvious redshifts compared to the SH-6 dye, and the maximum absorption peaks of eight dyes are greater than 650 nm among the newly designed dyes. In particular, BUCT27 exhibits a 234 nm redshift and the maximum molar extinction coefficient with an increment of about 80% compared to the SH-6 dye. BUCT19 exhibits not only a 269 nm redshift and higher molar extinction coefficient with an increment of about 50% compared to the SH-6 dye, but the extremely broad absorption spectrum covering the entire visible range up to the near-IR region of 1200 nm. It is expected that this work can provide a new strategy and guidance for the investigation of these dye-sensitized devices.

  7. Spectral sensitization of nanocrystalline solar cells

    DOEpatents

    Spitler, Mark T.; Ehret, Anne; Stuhl, Louis S.

    2002-01-01

    This invention relates to dye sensitized polycrystalline photoelectrochemical solar cells for use in energy transduction from light to electricity. It concerns the utility of highly absorbing organic chromophores as sensitizers in such cells and the degree to which they may be utilized alone and in combination to produce an efficient photoelectrochemical cell, e.g., a regenerative solar cell.

  8. Wrinkled silica/titania nanoparticles with tunable interwrinkle distances for efficient utilization of photons in dye-sensitized solar cells

    PubMed Central

    Kang, Jin Soo; Lim, Joohyun; Rho, Won-Yeop; Kim, Jin; Moon, Doo-Sik; Jeong, Juwon; Jung, Dongwook; Choi, Jung-Woo; Lee, Jin-Kyu; Sung, Yung-Eun

    2016-01-01

    Efficient light harvesting is essential for the realization of high energy conversion efficiency in dye-sensitized solar cells (DSCs). State-of-the-art mesoporous TiO2 photoanodes fall short for collection of long-wavelength visible light photons, and thus there have been efforts on introduction of scattering nanoparticles. Herein, we report the synthesis of wrinkled silica/titania nanoparticles with tunable interwrinkle distances as scattering materials for enhanced light harvesting in DSCs. These particles with more than 20 times larger specific surface area (>400 m2/g) compared to the spherical scattering particles (<20 m2/g) of the similar sizes gave rise to the dye-loading amounts, causing significant improvements in photocurrent density and efficiency. Moreover, dependence of spectral scattering properties of wrinkled particles on interwrinkle distances, which was originated from difference in overall refractive indices, was observed. PMID:27488465

  9. Fabrications and characterizations of dye-sensitized solar cells (DSSCs) with sol-gel derived gel electrolytes

    NASA Astrophysics Data System (ADS)

    Sukmawati Arsyad, Wa Ode; Pujiarti, Herlin; Tola, Pardi Sampe; Herman, Hidayat, Rahmat

    2013-09-01

    Dye Sensitized Solar Cells (DSSCs) have been fabricated by using sol-gel derived polymer gel electrolytes incorporating imidazolium ionic liquid. Two kinds of polymer gel electrolytes have been prepared. The first one is composed of siloxane polymer only, while the second one is composed of blend of siloxane and ethylene glycol polymers. The fabricated DSSC have the same structure configuration, namely ITO/Ti:ZnO/TiO2/Ru-dye/gelelectrolyte/Pt/ITO. DSSCs with the second type of gel electrolyte were found to exhibit much better photovoltaic performance in comparison to those with the first type of gel electrolyte. This fact is in agreement with the results from impedance spectroscopy measurements, which indicate more facile charge transfer process and much smaller ionic polarizations in the cell with the second type of gel electrolyte.

  10. Nanocomposite of tin sulfide nanoparticles with reduced graphene oxide in high-efficiency dye-sensitized solar cells.

    PubMed

    Yang, Bo; Zuo, Xueqin; Chen, Peng; Zhou, Lei; Yang, Xiao; Zhang, Haijun; Li, Guang; Wu, Mingzai; Ma, Yongqing; Jin, Shaowei; Chen, Xiaoshuang

    2015-01-14

    A nanocomposite of SnS2 nanoparticles with reduced graphene oxide (SnS2@RGO) had been successfully synthesized as a substitute conventional Pt counter electrode (CE) in a dye-sensitized solar cell (DSSC) system. The SnS2 nanoparticles were uniformly dispersed onto graphene sheets, which formed a nanosized composite system. The effectiveness of this nanocomposite exhibited remarkable electrocatalytic properties upon reducing the triiodide, owning to synergistic effects of SnS2 nanoparticles dispersed on graphene sheet and improved conductivity. Consequently, the DSSC equipped with SnS2@RGO nanocomposite CE achieved power conversion efficiency (PCE) of 7.12%, which was higher than those of SnS2 nanoparticles (5.58%) or graphene sheet alone (3.73%) as CEs and also comparable to the value (6.79%) obtained with pure Pt CE as a reference.

  11. Efficient Dye-Sensitized Solar Cells Made from High Catalytic Ability of Polypyrrole@Platinum Counter Electrode.

    PubMed

    Ma, Xingping; Yue, Gentian; Wu, Jihuai; Lan, Zhang

    2015-12-01

    Polypyrrole@platinum (PPy@Pt) composite film was successfully synthesized by using a one-step electrochemical method and served as counter electrode (CE) for efficient dye-sensitized solar cells (DSSCs). The PPy@Pt CE with one-dimensional structure exhibited excellent electrocatalytic activity and superior charge transfer resistance for I(-)/I3 (-) electrolyte after being the cyclic voltammetry and electrochemical impedance spectroscopy tested. The photocurrent-photovoltage curves were further used to calculate the theoretical photoelectric performance parameters of the DSSCs. The DSSC based on the PPy@Pt CE achieved a remarkable power conversion efficiency of 7.35 %, higher about 19.9 % than that of conventional Pt CE (6.13 %). This strategy provides a new opportunity for fabricating low-cost and highly efficient DSSCs.

  12. Efficient Dye-Sensitized Solar Cells Made from High Catalytic Ability of Polypyrrole@Platinum Counter Electrode

    NASA Astrophysics Data System (ADS)

    Ma, Xingping; Yue, Gentian; Wu, Jihuai; Lan, Zhang

    2015-08-01

    Polypyrrole@platinum (PPy@Pt) composite film was successfully synthesized by using a one-step electrochemical method and served as counter electrode (CE) for efficient dye-sensitized solar cells (DSSCs). The PPy@Pt CE with one-dimensional structure exhibited excellent electrocatalytic activity and superior charge transfer resistance for I-/I3 - electrolyte after being the cyclic voltammetry and electrochemical impedance spectroscopy tested. The photocurrent-photovoltage curves were further used to calculate the theoretical photoelectric performance parameters of the DSSCs. The DSSC based on the PPy@Pt CE achieved a remarkable power conversion efficiency of 7.35 %, higher about 19.9 % than that of conventional Pt CE (6.13 %). This strategy provides a new opportunity for fabricating low-cost and highly efficient DSSCs.

  13. Biological construction of single-walled carbon nanotube electron transfer pathways in dye-sensitized solar cells.

    PubMed

    Inoue, Ippei; Watanabe, Kiyoshi; Yamauchi, Hirofumi; Ishikawa, Yasuaki; Yasueda, Hisashi; Uraoka, Yukiharu; Yamashita, Ichiro

    2014-10-01

    We designed and mass-produced a versatile protein supramolecule that can be used to manufacture a highly efficient dye-sensitized solar cell (DSSC). Twelve single-walled carbon-nanotube (SWNT)-binding and titanium-mineralizing peptides were genetically integrated on a cage-shaped dodecamer protein (CDT1). A process involving simple mixing of highly conductive SWNTs with CDT1 followed by TiO2 biomineralization produces a high surface-area/weight TiO2 -(anatase)-coated intact SWNT nanocomposite under environmentally friendly conditions. A DSSC with a TiO2 photoelectrode containing 0.2 wt % of the SWNT-TiO2 nanocomposite shows a current density improvement by 80% and a doubling of the photoelectric conversion efficiency. The SWNT-TiO2 nanocomposite transfers photon-generated electrons from dye molecules adsorbed on the TiO2 to the anode electrode swiftly.

  14. Analysis of dye-sensitized solar cells with current collecting electrodes using electrochemical impedance spectroscopy, with a finite element method

    NASA Astrophysics Data System (ADS)

    Shitanda, Isao; Inoue, Kazuya; Hoshi, Yoshinao; Itagaki, Masayuki

    2014-02-01

    The internal resistances of dye-sensitized solar cells (DSCs) with and without current collecting electrodes (CCEs) were analyzed using electrochemical impedance spectroscopy (EIS) with a finite element method (FEM). Three different DSC models with or without current collecting electrodes were designed. Theoretical values of the internal resistance were estimated by FEM on changing the position and size of the current collecting electrodes. Large DSCs with current collecting electrodes were fabricated using a screen-printing technique, and experimental values of the internal resistance were analyzed by EIS and compared with the theoretical values. The internal resistances obtained from the impedance measurements were in good agreement with those obtained by simulation. The internal resistance was found to decrease with increasing width and thickness of the CCEs, below a threshold value. EIS was found to be extremely useful for evaluating CCE design for improved DSCs.

  15. Enhanced performance of dye-sensitized solar cells based on P25/Ta2O5 composite films

    NASA Astrophysics Data System (ADS)

    Jiang, Qingsong; Gao, Jian; Yi, Lin; Hu, Guang; Zhang, Jun

    2016-04-01

    In this paper, novel titanium dioxide/tantalum pentoxide (P25/Ta2O5) composite films have been successfully fabricated and applied to dye-sensitized solar cells (DSSCs). Ta2O5 nanoparticles are synthesized by a simple low-temperature solvothermal method. The influence of Ta2O5 nanoparticles on photovoltaic performance of DSSCs is systematically investigated. As a result, the DSSC based on 10 wt% Ta2O5 incorporated P25 film exhibits excellent photovoltaic performance with a power conversion efficiency (PCE) as high as 5.85 %. Compared to a reference DSSC based on the pure P25 film (4.93 %), the PCE of DSSCs has been remarkably enhanced by 19 %. Such enhancement can be mainly attributed to the higher electron collection efficiency in P25/Ta2O5 composite films, which result from the suppression of the electron recombination at the photoanode/electrolyte interface.

  16. Wrinkled silica/titania nanoparticles with tunable interwrinkle distances for efficient utilization of photons in dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Kang, Jin Soo; Lim, Joohyun; Rho, Won-Yeop; Kim, Jin; Moon, Doo-Sik; Jeong, Juwon; Jung, Dongwook; Choi, Jung-Woo; Lee, Jin-Kyu; Sung, Yung-Eun

    2016-08-01

    Efficient light harvesting is essential for the realization of high energy conversion efficiency in dye-sensitized solar cells (DSCs). State-of-the-art mesoporous TiO2 photoanodes fall short for collection of long-wavelength visible light photons, and thus there have been efforts on introduction of scattering nanoparticles. Herein, we report the synthesis of wrinkled silica/titania nanoparticles with tunable interwrinkle distances as scattering materials for enhanced light harvesting in DSCs. These particles with more than 20 times larger specific surface area (>400 m2/g) compared to the spherical scattering particles (<20 m2/g) of the similar sizes gave rise to the dye-loading amounts, causing significant improvements in photocurrent density and efficiency. Moreover, dependence of spectral scattering properties of wrinkled particles on interwrinkle distances, which was originated from difference in overall refractive indices, was observed.

  17. Ni(III)/(IV) Bis(dicarbollide) as a Fast, Noncorrosive Redox Shuttle for Dye-Sensitized Solar Cells

    SciTech Connect

    Li, Tina C.; Spokoyny, Alexander M.; She, Chunxing; Farha, Omar K.; Mirkin, Chad; Marks, Tobin J.; Hupp, Joseph T.

    2010-04-07

    Nickel bis(dicarbollide) is used as a fast, one-electron outer sphere redox couple in dye-sensitized solar cells. Device performances with this anionic shuttle are investigated with different electrolyte concentrations and additives, using only 0.030 M of the Ni(III) bis(dicarbollide) to efficiently regenerate the ruthenium dye. Atomic layer deposition of Al{sub 2}O{sub 3} on the nanoparticulate TiO{sub 2} photoanodes is further used to improve device performances, increasing current densities almost 2-fold and attaining power conversion efficiencies 10× greater than its metallocene analogue, ferrocene/ferrocenium. Open-circuit voltage decay is used to probe the kinetics of the Ni(III)/(IV) bis(dicarbollide) redox couple, and electron interception is found to be 10{sup 3}× slower than ferrocene/ferrocenium, explaining the large discrepancy in open-circuit voltage potentials between these two redox shuttles.

  18. Ni(III)/(IV) Bis(dicarbollide) as a Fast, Noncorrosive Redox Shuttle for Dye-Sensitized Solar Cells

    SciTech Connect

    Li, Tina C.; Spokoyny, Alexander M.; Chunxing, She; Farha, Omar K.; Mirkin, Chad A.; Marks, Tobin J.; Hupp, Joseph T.

    2010-01-01

    Nickel bis(dicarbollide) is used as a fast, one-electron outer sphere redox couple in dye-sensitized solar cells. Device performances with this anionic shuttle are investigated with different electrolyte concentrations and additives, using only 0.030 M of the Ni(III) bis(dicarbollide) to efficiently regenerate the ruthenium dye. Atomic layer deposition of Al₂O₃ on the nanoparticulate TiO₂ photoanodes is further used to improve device performances, increasing current densities almost 2-fold and attaining power conversion efficiencies ~10× greater than its metallocene analogue, ferrocene/ferrocenium. Open-circuit voltage decay is used to probe the kinetics of the Ni(III)/(IV) bis(dicarbollide) redox couple, and electron interception is found to be ~10₃× slower than ferrocene/ferrocenium, explaining the large discrepancy in open-circuit voltage potentials between these two redox shuttles.

  19. Improvement in performance of dye-sensitized solar cells with porous TiO2 electrodes using squid ink particles

    NASA Astrophysics Data System (ADS)

    Matsuura, Toshihiko; Nagai, Sakura; Ogasawara, Kou; Minato, Ken-ichi; Sakai, Mitsuo; Ueno, Takashi

    2016-06-01

    A potentially appealing alternative to the traditional fabrication process of TiO2 film electrodes for dye-sensitized solar cells (DSSCs) was presented by utilizing water-soluble TiO2 composite pastes containing size-controlled ink particles (SIPs) isolated from the squid. The mixture ratios of SIPs in the paste formulations affected the photoelectric conversion efficiency (PCE). The highest PCE was achieved when the mixture ratio of SIPs was 20%. The process is highly reproducible and leads to a 35% increase in PCE compared with that in the DSSC without SIP addition. The utilization of SIPs in the fabrication of TiO2 film electrodes enhanced the performance of DSSCs.

  20. Role of functionalized acceptors in heteroleptic bipyridyl Cu(I) complexes for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Lu, Xiaoqing; Shao, Yang; Li, Ke; Zhao, Zigang; Wei, Shuxian; Guo, Wenyue

    2016-09-01

    The intrinsic optoelectronic properties of heteroleptic bipyridyl Cu(I) complexes bearing functionalized acceptor subunits have been investigated by density functional theory and time-dependent DFT. The Cu(I) complexes exhibit distorted trigonal-pyramidal geometries and typical metal-to-ligand electron transfer characteristics at the long wavelength region. Replacing carboxylic acid with cyanoacrylic acid in acceptor subunits stabilizes the LUMO levels, thus lowering the HOMOLUMO energy gaps and facilitating favorable donor-to-acceptor intramolecular electron transfer and charge separation. Introduction of heteroaromatic groups and cyanoacrylic acid significantly improves the light-harvesting capability of the complexes. Our results highlight the effect of functionalized acceptors on the optoelectronic properties of bipyridyl Cu(I) complexes and provide a fresh perspective on screening of efficient sensitizers for dye-sensitized solar cells.

  1. In situ Poly(methyl methacrylate)/Graphene Composite Gel Electrolytes for Highly Stable Dye-Sensitized Solar Cells.

    PubMed

    Kang, Yu-il; Moon, Jun Hyuk

    2015-11-01

    Dye-sensitized solar cells (DSCs) with long-term stability are produced using polymer-gel electrolytes (PGEs). In this study, we introduce the formation of PGEs using in situ gelation with poly(methyl methacrylate) (PMMA) particles and graphene fillers that are pre-deposited on the counter electrodes. We obtain a high concentration PMMA-based PGEs (i.e., over 10 wt%). A DSC composed of a PMMA/graphene composite PGEs exhibits an 8.49% photon-to-electric conversion efficiency, which is comparable to conventional liquid electrolyte DSCs. This finding is attributed to increased ion diffusivity and conductivity of the PMMA-based PGEs resulting from the incorporation of graphene nanofillers. The PMMA-based PGE DSCs exhibit highly stable long-term efficiencies, maintaining up to 90% of their initial efficiency during thermal soaking, whereas the efficiencies of liquid electrolyte cells decrease significantly, by up to 60%. PMID:26471468

  2. Novel 4'-functionalized 4,4''-dicarboxyterpyridine ligands for ruthenium complexes: near-IR sensitization in dye sensitized solar cells.

    PubMed

    Koyyada, Ganesh; Botla, Vinayak; Thogiti, Suresh; Wu, Guohua; Li, Jingzhe; Fang, Xiaqin; Kong, Fantai; Dai, Songyuan; Surukonti, Niveditha; Kotamarthi, Bhanuprakash; Malapaka, Chandrasekharam

    2014-10-28

    Novel ruthenium complexes (MC113-MC117), obtained by modifying the terpyridine ligand of the black dye (N749), have been evaluated as sensitizers for dye sensitized solar cells (DSSCs). The modification is carried out by attaching selected chromophores, with varying electron donating strength, covalently to the central ring of the ligand. The complexes, compared to the parent dye, show red shifted absorption covering visible and near IR regions and higher molar extinction coefficients. We report in this work synthesis of a series of these ruthenium complexes with chromophores such as tert-butyl phenyl, triphenylamine, bithiophene, phenoxazine and phenothiazine. Detailed experimental characterization using optical, electrochemical and photovoltaic techniques has been carried out and complemented by density functional theory studies. The fill factors (ff) obtained for these dyes are larger than those of the parent black dye. In spite of these superior properties, the dyes show only moderate to good power conversion efficiencies. The possible reasons for this have been investigated and discussed.

  3. Mesoporous titania-vertical nanorod films with interfacial engineering for high performance dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Ahmed, Irfan; Fakharuddin, Azhar; Wali, Qamar; Zainun, Ayib Rosdi Bin; Ismail, Jamil; Jose, Rajan

    2015-03-01

    Working electrode (WE) fabrication offers significant challenges in terms of achieving high-efficiency dye-sensitized solar cells (DSCs). We have combined the beneficial effects of vertical nanorods grown on conducting glass substrate for charge transport and mesoporous particles for dye loading and have achieved a high photoconversion efficiency of (η) > 11% with an internal quantum efficiency of ˜93% in electrode films of thickness ˜7 ± 0.5 μm. Controlling the interface between the vertical nanorods and the mesoporous film is a crucial step in attaining high η. We identify three parameters, viz., large surface area of nanoparticles, increased light scattering of the nanorod-nanoparticle layer, and superior charge transport of nanorods, that simultaneously contribute to the improved photovoltaic performance of the WE developed.

  4. Synthesis and Characterization of Phenothiazine-Based Platinum(II)-Acetylide Photosensitizers for Efficient Dye-Sensitized Solar Cells.

    PubMed

    Siu, Chi-Ho; Lee, Lawrence Tien Lin; Yiu, Sze-Chun; Ho, Po-Yu; Zhou, Panwang; Ho, Cheuk-Lam; Chen, Tao; Liu, Jianyong; Han, Keli; Wong, Wai-Yeung

    2016-03-01

    Three new unsymmetrical phenothiazine-based platinum(II) bis(acetylide) complexes PT1-PT3 with different electron-donating arylacetylide ligands were synthesized and characterized. Their photophysical, electrochemical, and photovoltaic properties have been fully investigated and the density functional theory (DFT) calculations have been carried out. Under AM 1.5 irradiation (100 mW cm(-2)), the PT1-based dye-sensitized solar cell (DSSC) device exhibited an attractive power conversion efficiency (η) up to 5.78 %, with a short-circuit photocurrent density (J(sc)) of 10.98 mA cm(-2), an open-circuit photovoltage (V(oc)) of 0.738 V, and a fill factor (ff) of 0.713. These findings provide strong evidence that platinum-acetylide complexes have great potential as promising photosensitizers in DSSC applications. PMID:26660631

  5. 1D nanorod-planted 3D inverse opal structures for use in dye-sensitized solar cells.

    PubMed

    Park, Yesle; Lee, Jung Woo; Ha, Su-Jin; Moon, Jun Hyuk

    2014-03-21

    The effectiveness of the 1D nanorod (NR)-planted 3D inverse opal (IO) structure as an electrode for dye-sensitized solar cells (DSSCs) is demonstrated here. The NRs were grown on the surface of a macroporous IO structure and their longitudinal growth increased the surface area of the structure proportional to the growth duration. NR/IO electrodes with various NR growth times were compared. A remarkable JSC was obtained for the DSSCs utilizing a NR/IO electrode. The improvement of the JSC was analyzed in terms of its efficiency in light harvesting and electron transport. The growth of the NRs improved the dye adsorption density and scattering property of the electrode, resulting in an improvement in the light harvesting efficiency. Electrochemical impedance analysis revealed that the NRs also improved its electron transport properties. Further growth of the NRs tended to limit the increase of the JSC, which could be attributed to an overlap between them. PMID:24356878

  6. Absorbency and conductivity of quasi-solid-state polymer electrolytes for dye-sensitized solar cells: A characterization review

    NASA Astrophysics Data System (ADS)

    Mohamad, Ahmad Azmin

    2016-10-01

    The application of quasi-solid state electrolytes for dye-sensitized solar cells opens up an interesting research field to explore, which is evident from the increasing amount of publications on this topic. Since 2010, significant progress has been made with new and more complicated quasi-solid-states materials being produced. The optimization of new materials requires specific characterizations. This review presents a comprehensive overview and recent progress of characterization methods for studying quasi-solid-state electrolytes. Emphasis is then placed on the absorbency and conductivity characterizations. Each characterization will be reviewed according to the objective, experimental set-up, summary of important outcomes, and a few case studies worth discussing. Finally, strategies for future characterizations and developments are described.

  7. The Structure-property Relationships of D-π-A BODIPY Dyes for Dye-sensitized Solar Cells.

    PubMed

    Mao, Mao; Song, Qin-Hua

    2016-04-01

    BODIPY dyes have attracted considerable attention as potential photosensitizers in dye-sensitized solar cells (DSSCs) owing to their excellent optical properties and facile structural modification. This account focuses on recent advances in the molecular design of D-π-A BODIPY dyes for applications in DSSCs. Special attention has been paid to the structure-property relationships of D-π-A BODIPY dyes for DSSCs. The developmental process in the modified position at the BODIPY core with a donor/acceptor is described. The devices based on 2,6-modified BODIPY dyes exhibit better photovoltaic performance over other modified BODIPY dyes. Meanwhile, the research reveals the correlation of molecular structures (various donor chromophores, extended units, molecular frameworks, and long alkyl groups) with their photophysical and electrochemical properties and relates it to their performance in DSSCs. The structure-property relationships give valuable information and guidelines for designing new D-π-A BODIPY dyes for DSSCs. PMID:26846846

  8. Ytterbium oxide nanodots via block copolymer self-assembly and their efficacy to dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Park, Kwang-Won; Ahn, Sungwoo; Lim, Sung-Hwan; Jin, Ming Hao; Song, Jeemin; Yun, Seung-Young; Kim, Hyeon Mo; Kim, Gi Jeong; Ok, Kang Min; Hong, Jongin

    2016-02-01

    In this study, we develop a novel phosphor, Yb2O3, to be used as the spectral converter in dye-sensitized solar cells (DSSCs) for the efficient capture of ultraviolet light via down-conversion. These zero-dimensional nanodots with a high refractive index also allow more light to be trapped and can prevent charge recombination at the interfaces in the DSSCs. Compared to DSSCs without the nanodots, the DSSCs fabricated with the Yb2O3 nanodots exhibits higher power-conversion efficiencies for both the N719 (10.5%) and CSD-01 (20.5%) dyes. The multifunctionality of the Yb2O3 nanodots provides a new route for improving the performance of DSSCs.

  9. Interaction of YD2 and TiO₂ in dye-sensitized solar cells (DSSCs): a density functional theory study.

    PubMed

    Mendizabal, Fernando; Lopéz, Alfredo; Arratia-Pérez, Ramiro; Inostroza, Natalia; Linares-Flores, Cristian

    2015-09-01

    The interaction of the dye YD2 with a cluster of (anatase-phase) TiO2 (which is utilized in dye-sensitized solar cells, DSSCs) and electron injection by the dye into the cluster were studied by performing density functional theory (DFT) calculations at the B3LYP, PBE, and TPSS levels of theory, including dispersion effects. We studied and quantified the interaction of the metallomacrocycle with the TiO2 cluster and the electronic spectrum of the complex. TDDFT calculations using the B3LYP functional were found to be the most suitable for describing the observed absorption energy bands of YD2 and YD2-TiO2. Our calculations show that the diarylamino groups act as electron donors in the photon-induced injection that occurs in DSSCs. The free-energy changes that take place during electron injection support the good performance of YD2 on TiO2 clusters.

  10. Effect of TiO2 blocking layer on TiO2 nanorod arrays based dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Sivakumar, R.; Paulraj, M.

    2016-05-01

    Highly ordered rutile titanium dioxide nanorod (TNR) arrays (1.2 to 6.2 μm thickness) were grown on TiO2 blocking layer chemically deposited on fluorine doped tin oxide (FTO) substrate and were used as photo-electrodes to fabricate dye sensitized solar cells (DSSC's). Homogeneous layer of TiO2 on FTO was achieved by using aqueous peroxo- titanium complex (PTC) solutions via chemical bath deposition. Structural and morphological properties of the prepared samples were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM) measurements. TNR arrays (6.2 μm) with TiO2 blocking layer showed higher energy conversion efficiency (1.46%) than that without TiO2 blocking layer. The reason can be ascertained to the suppression of electron-hole recombination at the semiconductor/electrolyte interface by the effect of TiO2 blocking layer.

  11. Facet-Dependent Catalytic Activity of Platinum Nanocrystals for Triiodide Reduction in Dye-Sensitized Solar Cells

    PubMed Central

    Zhang, Bo; Wang, Dong; Hou, Yu; Yang, Shuang; Yang, Xiao Hua; Zhong, Ju Hua; Liu, Jian; Wang, Hai Feng; Hu, P.; Zhao, Hui Jun; Yang, Hua Gui

    2013-01-01

    Platinum (Pt) nanocrystals have demonstrated to be an effective catalyst in many heterogeneous catalytic processes. However, pioneer facets with highest activity have been reported differently for various reaction systems. Although Pt has been the most important counter electrode material for dye-sensitized solar cells (DSCs), suitable atomic arrangement on the exposed crystal facet of Pt for triiodide reduction is still inexplicable. Using density functional theory, we have investigated the catalytic reaction processes of triiodide reduction over {100}, {111} and {411} facets, indicating that the activity follows the order of Pt(111) > Pt(411) > Pt(100). Further, Pt nanocrystals mainly bounded by {100}, {111} and {411} facets were synthesized and used as counter electrode materials for DSCs. The highest photovoltaic conversion efficiency of Pt(111) in DSCs confirms the predictions of the theoretical study. These findings have deepened the understanding of the mechanism of triiodide reduction at Pt surfaces and further screened the best facet for DSCs successfully. PMID:23670438

  12. Insights into aggregation effects on optical property and electronic coupling of organic dyes in dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Feng, Shuai; Li, Quan-Song; Yang, Li-Na; Sun, Zhu-Zhu; Niehaus, Thomas A.; Li, Ze-Sheng

    2015-01-01

    Combining density functional theory (DFT), time-dependent DFT, and density functional tight binding (DFTB) methods, we present a computational investigation on the aggregation effects of two organic dyes, WS-2 and WS-6, which are used as sensitizers in dye sensitized solar cells (DSSCs). The calculated absorption and emission spectra in solution and on TiO2 agree well with the experimental observations, which demonstrate WS-6 is less prone to aggregation due to a hexyl substituent on the thiophene ring compared to WS-2. Importantly, our results predict strong aggregation interactions inducing larger electronic coupling between the stacking dimers, which may be detrimental for electronic injection from dye to TiO2 and partly responsible for the loss of photo-voltaic efficiency. The deeper understanding of the dye aggregation effects shed lights on a better knowledge about the complex factors determining the function of DSSC and rational design of high efficiency sensitizers.

  13. Bifacial dye-sensitized solar cells from covalent-bonded polyaniline-multiwalled carbon nanotube complex counter electrodes

    NASA Astrophysics Data System (ADS)

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

    2015-02-01

    Exploration of cost-effective counter electrodes (CEs) and enhancement of power conversion efficiency have been two persistent objectives for dye-sensitized solar cells (DSSCs). In the current work, polyaniline-multiwalled carbon nanotube (PANi-MWCNT) complexes are synthesized by a reflux method and employed as CE materials for bifacial DSSCs. Owing to the high optical transparency of PANi-MWCNT complex CE, the incident light from rear side can compensate for the incident light from TiO2 anode. The charge-transfer ability and electrochemical behaviors demonstrate the potential utilization of PANi-MWCNT complex CEs in robust bifacial DSSCs. The electrochemical properties as well as photovoltaic performances are optimized by adjusting MWCNT dosages. A maximum power conversion efficiency of 9.24% is recorded from the bifacial DSSC employing PANi-8 wt‰ MWCNT complex CE for both irradiation, which is better than 8.08% from pure PANi CE.

  14. Effect of incorporation of reduced graphene oxide on ZnO-based dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Song, Jun-Ling; Wang, Xiu

    2016-07-01

    Here, we demonstrate a facile method to improve the cell performance of ZnO-based dye sensitized solar cell by incorporating different amount of reduced graphene oxide (rGO). Overall photo-to-current conversion-efficiency (PCE) of the device 3 with 0.75 mL rGO exhibits a 1.3 times improvement compared to bare ZnO. The electrochemical impedance spectroscopy (EIS) measurements show that the enhancement could be attributed to the improvement of electron transport/injection and the decrease of the charge recombination in the device, which arise from the formation of rGO-based Schottky junction in ZnO-photoanode.

  15. Wrinkled silica/titania nanoparticles with tunable interwrinkle distances for efficient utilization of photons in dye-sensitized solar cells.

    PubMed

    Kang, Jin Soo; Lim, Joohyun; Rho, Won-Yeop; Kim, Jin; Moon, Doo-Sik; Jeong, Juwon; Jung, Dongwook; Choi, Jung-Woo; Lee, Jin-Kyu; Sung, Yung-Eun

    2016-01-01

    Efficient light harvesting is essential for the realization of high energy conversion efficiency in dye-sensitized solar cells (DSCs). State-of-the-art mesoporous TiO2 photoanodes fall short for collection of long-wavelength visible light photons, and thus there have been efforts on introduction of scattering nanoparticles. Herein, we report the synthesis of wrinkled silica/titania nanoparticles with tunable interwrinkle distances as scattering materials for enhanced light harvesting in DSCs. These particles with more than 20 times larger specific surface area (>400 m(2)/g) compared to the spherical scattering particles (<20 m(2)/g) of the similar sizes gave rise to the dye-loading amounts, causing significant improvements in photocurrent density and efficiency. Moreover, dependence of spectral scattering properties of wrinkled particles on interwrinkle distances, which was originated from difference in overall refractive indices, was observed. PMID:27488465

  16. Enhanced performance of TiO2 nanoparticle and aerogel composite electrode for dye sensitized solar cell.

    PubMed

    Kim, Chang-Yeoul; Park, Yu-Sik; Hwang, Hae-Jin

    2012-04-01

    To evaluate the effects of specific surface area to the photocurrent conversion efficiency of dye-sensitized solar cell (DSC), we adopted TiO2 aerogel (TA)/nanoparticle (TP) composite as a photoelectrode. We prepared three types of photoelectrodes, TPs, TAs, and TATPs (1:1 TAs and TPs composite photoelectrode). The performance of TATP composite electrode was compared with that of TP and TAs. TATPs showed the improved cell efficiency, more than 0.5%, compared with a reference TPs below 15 micrometer thickness. Although the introduction of TAs increases the specific surface area for the dye adsorption, DSC composed of only TAs does not show the best efficiency result due to the crack generation. In conclusion, to produce the best photocurrent conversion efficiency, the high specific surface area of TiO2 photoelectrode for high dye adsorption should be balanced with proper control of the good electron transfer path. PMID:22849065

  17. Synthesis of nanostructured CuInS2 thin films and their application in dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Zhao, Yu; Luo, Fazhi; Zhuang, Mixue; Liu, Zhen; Wei, Aixiang; Liu, Jun

    2016-03-01

    CuInS2 (CIS) nanostructure thin films were successfully synthesized on FTO conductive glass substrates by solvothermal method. It is found that the surface morphology and microstructure of CIS thin films can be tailored by simply adjusting the concentration of oxalic acid. CIS nanostructure films with texture of "nanosheet array" and "flower-like microsphere" were obtained and used as Pt-free counter electrode for dye-sensitized solar cells (DSSCs). The nanosheet array CIS was found to have a better electrocatalytic activity than the flower-like microsphere one. DSSCs based on nanosheet array CIS thin film counter electrode show conversion efficiency of 3.33 %, which is comparable to the Pt-catalyzed DSSCs. The easy synthesis, low cost, morphology tunable and excellent electrocatalytic property may make the CuInS2 nanostructure competitive as counter electrode in DSSCs.

  18. In situ Poly(methyl methacrylate)/Graphene Composite Gel Electrolytes for Highly Stable Dye-Sensitized Solar Cells.

    PubMed

    Kang, Yu-il; Moon, Jun Hyuk

    2015-11-01

    Dye-sensitized solar cells (DSCs) with long-term stability are produced using polymer-gel electrolytes (PGEs). In this study, we introduce the formation of PGEs using in situ gelation with poly(methyl methacrylate) (PMMA) particles and graphene fillers that are pre-deposited on the counter electrodes. We obtain a high concentration PMMA-based PGEs (i.e., over 10 wt%). A DSC composed of a PMMA/graphene composite PGEs exhibits an 8.49% photon-to-electric conversion efficiency, which is comparable to conventional liquid electrolyte DSCs. This finding is attributed to increased ion diffusivity and conductivity of the PMMA-based PGEs resulting from the incorporation of graphene nanofillers. The PMMA-based PGE DSCs exhibit highly stable long-term efficiencies, maintaining up to 90% of their initial efficiency during thermal soaking, whereas the efficiencies of liquid electrolyte cells decrease significantly, by up to 60%.

  19. Channeling of electron transport to improve collection efficiency in mesoporous titanium dioxide dye sensitized solar cell stacks

    SciTech Connect

    Fakharuddin, Azhar; Ahmed, Irfan; Yusoff, Mashitah M.; Jose, Rajan E-mail: joserajan@gmail.com; Khalidin, Zulkeflee

    2014-02-03

    Dye-sensitized solar cell (DSC) modules are generally made by interconnecting large photoelectrode strips with optimized thickness (∼14 μm) and show lower current density (J{sub SC}) compared with their single cells. We found out that the key to achieving higher J{sub SC} in large area devices is optimized photoelectrode volume (V{sub D}), viz., thickness and area which facilitate the electron channeling towards working electrode. By imposing constraints on electronic path in a DSC stack, we achieved >50% increased J{sub SC} and ∼60% increment in photoelectric conversion efficiency in photoelectrodes of similar V{sub D} (∼3.36 × 10{sup −4} cm{sup 3}) without using any metallic grid or a special interconnections.

  20. Gd-doped BiFeO3 nanoparticles - A novel material for highly efficient dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Lotey, Gurmeet Singh; Verma, N. K.

    2013-06-01

    This communication reports a novel idea on dye-sensitized solar cells (DSSCs) fabricated using Gd-doped BiFeO3 nanoparticles with particle size between 26 and 30 nm. The effect of Gd-doping and smaller size of synthesized nanoparticles on the structural, morphological, optical and photo-electrochemical properties have been investigated. The high energy-conversion efficiency, 3.85%, has been achieved for 12% Gd-doped BiFeO3 DSSCs, which is more than 100% higher than the undoped BiFeO3. The possible origin of the observed performance of DSSCs has been explained on the basis of smaller size of the synthesized nanoparticles, doping of Gd and structural transformation with doping in BiFeO3.

  1. Thiourea-succinonitrile based polymer matrix for efficient and stable quasi solid state dye sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Grover, Rakhi; Jauhari, Himanshi; Saxena, Kanchan

    2016-05-01

    Dye sensitized solar cells (DSSCs) are considered to be emerging alternatives to the low cost indoor photovoltaic technologies. However, to make the application of these cells economically feasible, the stability of the cells need to be enhanced. This can be achieved by employing solid or quasi solid state electrolytes to reduce the leakage and sealing problems in DSSCs. In the present work, a gel state electrolyte composition was successfully prepared using thiourea and solid state ionic conductor succinonitrile along with other components. The composition has been used for the fabrication of quasi solid state DSSCs using Eosin B as the sensitizer material. The cells fabricated exhibited consistent photovoltaic properties even after 24 hours of storage under ambient conditions without sealing. The present work therefore, demonstrates a rapid and simple preparation of electrolyte medium for quasi solid state DSSCs.

  2. The Structure-property Relationships of D-π-A BODIPY Dyes for Dye-sensitized Solar Cells.

    PubMed

    Mao, Mao; Song, Qin-Hua

    2016-04-01

    BODIPY dyes have attracted considerable attention as potential photosensitizers in dye-sensitized solar cells (DSSCs) owing to their excellent optical properties and facile structural modification. This account focuses on recent advances in the molecular design of D-π-A BODIPY dyes for applications in DSSCs. Special attention has been paid to the structure-property relationships of D-π-A BODIPY dyes for DSSCs. The developmental process in the modified position at the BODIPY core with a donor/acceptor is described. The devices based on 2,6-modified BODIPY dyes exhibit better photovoltaic performance over other modified BODIPY dyes. Meanwhile, the research reveals the correlation of molecular structures (various donor chromophores, extended units, molecular frameworks, and long alkyl groups) with their photophysical and electrochemical properties and relates it to their performance in DSSCs. The structure-property relationships give valuable information and guidelines for designing new D-π-A BODIPY dyes for DSSCs.

  3. Broadband light absorption enhancement in dye-sensitized solar cells with Au-Ag alloy popcorn nanoparticles

    NASA Astrophysics Data System (ADS)

    Xu, Qi; Liu, Fang; Liu, Yuxiang; Cui, Kaiyu; Feng, Xue; Zhang, Wei; Huang, Yidong

    2013-07-01

    In this paper, we present an investigation on the use of Au-Ag alloy popcorn-shaped nanoparticles (NPs) to realise the broadband optical absorption enhancement of dye-sensitized solar cells (DSCs). Both simulation and experimental results indicate that compared with regular plasmonic NPs, such as nano-spheres, irregular popcorn-shaped alloy NPs exhibit absorption enhancement over a broad wavelength range due to the excitation of localized surface plasmons (LSPs) at different wavelengths. The power conversion efficiency (PCE) of DSCs is enhanced by 16% from 5.26% to 6.09% by incorporating 2.38 wt% Au-Ag alloy popcorn NPs. Moreover, by adding a scattering layer on the exterior of the counter electrode, the popcorn NPs demonstrate an even stronger ability to increase the PCE by 32% from 5.94% to 7.85%, which results from the more efficient excitation of the LSP mode on the popcorn NPs.

  4. Efficient Dye-Sensitized Solar Cells Made from High Catalytic Ability of Polypyrrole@Platinum Counter Electrode.

    PubMed

    Ma, Xingping; Yue, Gentian; Wu, Jihuai; Lan, Zhang

    2015-12-01

    Polypyrrole@platinum (PPy@Pt) composite film was successfully synthesized by using a one-step electrochemical method and served as counter electrode (CE) for efficient dye-sensitized solar cells (DSSCs). The PPy@Pt CE with one-dimensional structure exhibited excellent electrocatalytic activity and superior charge transfer resistance for I(-)/I3 (-) electrolyte after being the cyclic voltammetry and electrochemical impedance spectroscopy tested. The photocurrent-photovoltage curves were further used to calculate the theoretical photoelectric performance parameters of the DSSCs. The DSSC based on the PPy@Pt CE achieved a remarkable power conversion efficiency of 7.35 %, higher about 19.9 % than that of conventional Pt CE (6.13 %). This strategy provides a new opportunity for fabricating low-cost and highly efficient DSSCs. PMID:26272804

  5. Effects of heat treatment on the dye adsorption of ZnO nanorods for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Yun, Won Suk; Choi, Seok Cheol; Sohn, Sang Ho; Oh, Sang Jin

    2012-11-01

    Well-aligned ZnO nanorods for the photoelectrode of dye-sensitized solar cells (DSSCs) were grown via a sonochemical method, and the heat-treatment effects on the dye adsorption in the DSSCs were studied. The heat treatment of well-aligned ZnO nanorods was performed at 200 ˜ 500 °C for 1 h, which was immediately followed by the dye adsorption. The dye amounts adsorbed in the ZnO nanorods were estimated from the UV-Vis absorbance by using Beer-Lambert's law. The efficiency of the DSSCs with ZnO nanorods was measured to investigate the heat-treatment effects of ZnO nanorods on the dye adsorption properties. The heat-treatment of ZnO nanorods was found to yield a change in their dye adsorption ability, resulting in a change in the efficiency of the DSSCs.

  6. Dye-sensitized solar cell based on spray deposited ZnO thin film: Performance analysis through DFT approach

    NASA Astrophysics Data System (ADS)

    Parthiban, R.; Balamurugan, D.; Jeyaprakash, B. G.

    2015-02-01

    A dye-sensitized solar cell based on a spray deposited zinc oxide (ZnO) photoanode with Evans blue as a sensitizer was fabricated. Structural analysis confirms the hexagonal wurtzite phase of the ZnO photoanode with c-axis orientation. Surface morphology of the ZnO photoanode shows uniform distribution of spherically-shaped grains, ranging from 18 nm to 25 nm. The power conversion efficiency of the device was measured as 0.1%. Density functional theory was adopted to study the observed photovoltaic performance of the fabricated device. The analysis of the electronic properties of Evans blue dye showed that it has a pronounced effect on the observed device performance.

  7. Dye-sensitized solar cell based on spray deposited ZnO thin film: performance analysis through DFT approach.

    PubMed

    Parthiban, R; Balamurugan, D; Jeyaprakash, B G

    2015-02-01

    A dye-sensitized solar cell based on a spray deposited zinc oxide (ZnO) photoanode with Evans blue as a sensitizer was fabricated. Structural analysis confirms the hexagonal wurtzite phase of the ZnO photoanode with c-axis orientation. Surface morphology of the ZnO photoanode shows uniform distribution of spherically-shaped grains, ranging from 18 nm to 25 nm. The power conversion efficiency of the device was measured as 0.1%. Density functional theory was adopted to study the observed photovoltaic performance of the fabricated device. The analysis of the electronic properties of Evans blue dye showed that it has a pronounced effect on the observed device performance. PMID:25459624

  8. Conducting glasses recovered from thin film transistor liquid crystal display wastes for dye-sensitized solar cell cathodes.

    PubMed

    Chen, C-C; Chang, F-C; Peng, C Y; Wang, H Paul

    2015-01-01

    Transparent conductive glasses such as thin film transistor (TFT) array and colour filter glasses were recovered from the TFT-liquid crystal display panel wastes by dismantling and sonic cleaning. Noble metals (i.e. platinum (Pt)) and indium tin oxide (ITO) are generally used in the cathode of a dye-sensitized solar cell (DSSC). To reduce the DSSC cost, Pt was replaced with nano nickel-encapsulated carbon-shell (Ni@C) nanoparticles, which were prepared by carbonization of Ni²⁺-β-cyclodextrin at 673 K for 2 h. The recovered conductive glasses were used in the DSSC electrodes in the substitution of relatively expensive ITO. Interestingly, the efficiency of the DSSC having the Ni@C-coated cathode is as high as 2.54%. Moreover, the cost of the DSSC using the recovered materials can be reduced by at least 24%. PMID:25399759

  9. A versatile chemical conversion synthesis of Cu2S nanotubes and the photovoltaic activities for dye-sensitized solar cell

    PubMed Central

    2014-01-01

    A versatile, low-temperature, and low-cost chemical conversion synthesis has been developed to prepare copper sulfide (Cu2S) nanotubes. The successful chemical conversion from ZnS nanotubes to Cu2S ones profits by the large difference in solubility between ZnS and Cu2S. The morphology, structure, and composition of the yielded products have been examined by field-emission scanning electron microscopy, transmission electron microscopy, and X-ray diffraction measurements. We have further successfully employed the obtained Cu2S nanotubes as counter electrodes in dye-sensitized solar cells. The light-to-electricity conversion results show that the Cu2S nanostructures exhibit high photovoltaic conversion efficiency due to the increased surface area and the good electrocatalytical activity of Cu2S. The present chemical route provides a simple way to synthesize Cu2S nanotubes with a high surface area for nanodevice applications. PMID:25246878

  10. Conducting glasses recovered from thin film transistor liquid crystal display wastes for dye-sensitized solar cell cathodes.

    PubMed

    Chen, C-C; Chang, F-C; Peng, C Y; Wang, H Paul

    2015-01-01

    Transparent conductive glasses such as thin film transistor (TFT) array and colour filter glasses were recovered from the TFT-liquid crystal display panel wastes by dismantling and sonic cleaning. Noble metals (i.e. platinum (Pt)) and indium tin oxide (ITO) are generally used in the cathode of a dye-sensitized solar cell (DSSC). To reduce the DSSC cost, Pt was replaced with nano nickel-encapsulated carbon-shell (Ni@C) nanoparticles, which were prepared by carbonization of Ni²⁺-β-cyclodextrin at 673 K for 2 h. The recovered conductive glasses were used in the DSSC electrodes in the substitution of relatively expensive ITO. Interestingly, the efficiency of the DSSC having the Ni@C-coated cathode is as high as 2.54%. Moreover, the cost of the DSSC using the recovered materials can be reduced by at least 24%.

  11. Mesoporous titania-vertical nanorod films with interfacial engineering for high performance dye-sensitized solar cells.

    PubMed

    Ahmed, Irfan; Fakharuddin, Azhar; Wali, Qamar; Bin Zainun, Ayib Rosdi; Ismail, Jamil; Jose, Rajan

    2015-03-13

    Working electrode (WE) fabrication offers significant challenges in terms of achieving high-efficiency dye-sensitized solar cells (DSCs). We have combined the beneficial effects of vertical nanorods grown on conducting glass substrate for charge transport and mesoporous particles for dye loading and have achieved a high photoconversion efficiency of (η) > 11% with an internal quantum efficiency of ∼93% in electrode films of thickness ∼7 ± 0.5 μm. Controlling the interface between the vertical nanorods and the mesoporous film is a crucial step in attaining high η. We identify three parameters, viz., large surface area of nanoparticles, increased light scattering of the nanorod-nanoparticle layer, and superior charge transport of nanorods, that simultaneously contribute to the improved photovoltaic performance of the WE developed. PMID:25687409

  12. Mesoporous nitrogen-doped TiO2 sphere applied for quasi-solid-state dye-sensitized solar cell

    PubMed Central

    2011-01-01

    A mesoscopic nitrogen-doped TiO2 sphere has been developed for a quasi-solid-state dye-sensitized solar cell [DSSC]. Compared with the undoped TiO2 sphere, the quasi-solid-state DSSC based on the nitrogen-doped TiO2 sphere shows more excellent photovoltaic performance. The photoelectrochemistry of electrodes based on nitrogen-doped and undoped TiO2 spheres was characterized with Mott-Schottky analysis, intensity modulated photocurrent spectroscopy, and electrochemical impedance spectroscopy, which indicated that both the quasi-Fermi level and the charge transport of the photoelectrode were improved after being doped with nitrogen. As a result, a photoelectric conversion efficiency of 6.01% was obtained for the quasi-solid-state DSSC. PMID:22115421

  13. A novel approach to titania nanowire arrays as photoanodes of back-illuminated dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Tao, Ru-Hua; Wu, Jin-Ming; Xue, Hong-Xing; Song, Xiao-Mei; Pan, Xu; Fang, Xia-Qin; Fang, Xiao-Dong; Dai, Song-Yuan

    Titania nanowire arrays have been deposited on Ti foils through direct oxidizing the Ti substrate with aqueous hydrogen peroxide solutions containing melamine and nitric acid, and the applicability of such nanowire arrays to back-illuminated dye-sensitized solar cells studied in parallel with titania nanotube arrays on Ti foils. The low-temperature nitrogen adsorption measurement reveals that the film with nanowires 25 nm in diameter and 1 μm in length possesses a BET specific surface area of 59.0 m 2 g -1, a value much larger than 26 m 2 g -1 calculated for the nanotube with an inner diameter of 80 nm, an outer diameter of 120 nm and a total length of 3 μm. Assuming an indirect transition between band gaps, the nanowire film exhibits a bandgap of 3.1 eV, slightly larger than that of 3.0 eV for the nanotube one. A detailed electrochemical study suggests that, in comparison with the nanotube film, the nanowire one exhibits much lower saturated photocurrent and poorer conductivity under the Xe-lamp irradiation. However, when utilized to construct back-side illuminated dye-sensitized solar cells, the cell with the 2 μm-thick nanowire photoanode possesses significantly higher efficiency than the one with the 3 μm-thick nanotube photoanode. The relatively high energy conversion efficiency is contributed to the high specific surface area and the unique mesoporous structure of the titania nanowire arrays, which favors the adsorption of dye molecules.

  14. Influence of the auxiliary acceptor on the absorption response and photovoltaic performance of dye-sensitized solar cells.

    PubMed

    Wu, ZhiFang; Li, Xin; Li, Jing; Hua, JianLi; Agren, Hans; Tian, He

    2014-12-01

    Three new dyes with a 2-(1,1-dicyanomethylene)rhodanine (IDR-I, -II, -III) electron acceptor as anchor were synthesized and applied to dye-sensitized solar cells. We varied the bridging molecule to fine tune the electronic and optical properties of the dyes. It was demonstrated that incorporation of auxiliary acceptors effectively increased the molar extinction coefficient and extended the absorption spectra to the near-infrared (NIR) region. Introduction of 2,1,3-benzothiadiazole (BTD) improved the performance by nearly 50 %. The best performance of the dye-sensitized solar cells (DSSCs) based on IDR-II reached 8.53 % (short-circuit current density (Jsc)=16.73 mA cm(-2), open-circuit voltage (Voc)=0.71 V, fill factor (FF)=71.26 %) at AM 1.5 simulated sunlight. However, substitution of BTD with a group that featured the more strongly electron-withdrawing thiadiazolo[3,4-c]pyridine (PT) had a negative effect on the photovoltaic performance, in which IDR-III-based DSSCs showed the lowest efficiency of 4.02 %. We speculate that the stronger auxiliary acceptor acts as an electron trap, which might result in fast combination or hamper the electron transfer from donor to acceptor. This inference was confirmed by electrical impedance analysis and theoretical computations. Theoretical analysis indicates that the LUMO of IDR-III is mainly localized at the central acceptor group owing to its strong electron-withdrawing character, which might in turn trap the electron or hamper the electron transfer from donor to acceptor, thereby finally decreasing the efficiency of electron injection into a TiO2 semiconductor. This result inspired us to select moderated auxiliary acceptors to improve the performance in our further study.

  15. Facile and effective synthesis of hierarchical TiO2 spheres for efficient dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Ye, Meidan; Chen, Chang; Lv, Miaoqiang; Zheng, Dajiang; Guo, Wenxi; Lin, Changjian

    2013-06-01

    Three-dimensional (3D) crystalline anatase TiO2 hierarchical spheres were successfully derived from Ti foils via a fast, template-free, low-temperature hydrothermal route followed by a calcination post-treatment. These dandelion-like TiO2 spheres are composed of numerous ultrathin nanoribbons, which were subsequently split into fragile nanoflakes as a result of the decomposition of Ti-complex intermediates to TiO2 and H2O at high temperature. The dye-sensitized solar cells (DSSCs) employing such hierarchically structured TiO2 spheres as the photoanodes exhibited a light-to-electricity conversion efficiency of 8.50%, yielding a 28% enhancement in comparison with that (6.64%) of P25-based DSSCs, which mainly benefited from the enhanced capacity of dye loading in combination with effective light scattering and trapping from hierarchical architecture.Three-dimensional (3D) crystalline anatase TiO2 hierarchical spheres were successfully derived from Ti foils via a fast, template-free, low-temperature hydrothermal route followed by a calcination post-treatment. These dandelion-like TiO2 spheres are composed of numerous ultrathin nanoribbons, which were subsequently split into fragile nanoflakes as a result of the decomposition of Ti-complex intermediates to TiO2 and H2O at high temperature. The dye-sensitized solar cells (DSSCs) employing such hierarchically structured TiO2 spheres as the photoanodes exhibited a light-to-electricity conversion efficiency of 8.50%, yielding a 28% enhancement in comparison with that (6.64%) of P25-based DSSCs, which mainly benefited from the enhanced capacity of dye loading in combination with effective light scattering and trapping from hierarchical architecture. Electronic supplementary information (ESI) available: FESEM images of samples prepared in other control experiments and a cross-sectional view of the three films. See DOI: 10.1039/c3nr01604h

  16. Development of Anti-Reflection Coating Layer for Efficiency Enhancement of ZnO Dye-Sensitized Solar Cells.

    PubMed

    Chanta, E; Bhoomanee, C; Gardchareon, A; Wongratanaphisan, D; Phadungdhitidhada, S; Choopun, S

    2015-09-01

    In this research, we investigated the effects of ZnO anti-reflection coating layers on power conversion efficiency enhancement of ZnO dye-sensitized solar cells. ZnO thin films were prepared by rf-magnetron sputtering by varying sputtering time of 10, 30, 60, 80, 100 min. Surface morphology, thickness and optical reflective index were investigated by field emission scanning electron microscopy and ellipsometry. Then, transmittance and reflectance were investigated by UV-vis spectroscopy. Furthermore, we found that ZnO anti-reflection coating layers with sputtering time of 30 and 60 min showed lower reflection and higher transmission than that of reference film. In addition, ZnO anti-reflection coating layers have rough surface with sputtering rate has 2.14 nm/min. Thus, the ZnO anti-reflection coating layers with sputtering time in the range of 10-60 min have a potential as anti-reflection coating applications. The ZnO anti-reflection coating layers were used in ZnO dye-sensitized solar cells and exhibited a short circuit current density of 5.16 mA/cm2 and the maximum power conversion efficiency of 1.54% from a sample with sputtering time at 60 min while the reference cell exhibited 3.88 mA/cm2 and 1.19%, respectively. Thus, we suggested an alternative improvement of ZnO DSSCs by adding the ZnO anti-reflection coating layers.

  17. Hybrid structure of polyaniline/ZnO nanograss and its application in dye-sensitized solar cell with performance improvement

    SciTech Connect

    Zhu Shibu; Wei Wei; Chen Xiangnan; Jiang Man; Zhou Zuowan

    2012-06-15

    Polyaniline (PANI) hybridized ZnO photoanode for dye-sensitized solar cell (DSSC) was primarily prepared via a two-step process which involved hydrothermal growth of ZnO nanograss on the fluorine-doped tin oxide (FTO) substrate and subsequently chemisorption of PANI on the surfaces of the ZnO nanorods. The PANI hybridized ZnO nanograss films were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD) and Fourier transform infrared spectra (FT-IR), and the results indicated that there were chemical interactions between PANI and ZnO. Both pure ZnO nanograss and PANI hybridized ZnO nanograss were applied to DSSC. The results of photoelectrochemical measurement showed that the photocurrent density of PANI (100 mg/L) hybridized ZnO nanograss photoanode was significantly enhanced, and the overall light-conversion efficiency increased by 60%. The electrochemical impedance spectra (EIS) displayed that the electron densities in photoanodes of PANI hybridized ZnO nanograss were larger than that in pure ZnO nanograss. This is ascribed to more effective charge separation and faster interfacial charge transferring occurred in the hybrid photoanode. - Graphical abstract: Operational principle of the DSSC: the introduced hybridizing PANI layer performs effective charge separation and faster interfacial charge transferring. Highlights: Black-Right-Pointing-Pointer PANI/ZnO nanograss hybrid materials as photoanode in Dye-sensitized solar cell. Black-Right-Pointing-Pointer Photoelectric conversion efficiency after hybridization was enhanced by 60%. Black-Right-Pointing-Pointer PANI hybridizing ZnO nanograss induced a rapid charge separation.

  18. Co-sensitization of natural dyes for improved efficiency in dye-sensitized solar cell application

    NASA Astrophysics Data System (ADS)

    Kumar, K. Ashok; Subalakshmi, K.; Senthilselvan, J.

    2016-05-01

    In this paper, a new approach of co-sensitized DSSC based on natural dyes is investigated to explore the possible way to improve the power conversion efficiency. To realize this purpose 10 DSSC devices were fabricated using mono-sensitization and co-sensitization of ethanolic extracts of natural dye sensitizers obtained from Cactus fruit, Jambolana fruit, Curcumin and Bermuda grass. The optical absorption spectrum of the mono and hybrid dye extracts were studied by UV-Visible absorption spectrum. It shows the characteristic absorption peaks in visible region corresponds to the presence of natural pigments of anthocyanin, betacyanin and chlorophylls. Absorption spectrum of hybrid dyes reveals a wide absorption band in visible region with improved extinction co-efficient and it is favorable for increased light harvesting nature. The power conversion efficiency of DSSC devices were calculated using J-V curve and the maximum efficiency achieved in the present work is noted to be ~0.61% for Cactus-Bermuda co-sensitized DSSC.

  19. Tunable localized surface plasmon-enabled broadband light harvesting enhancement for high-efficiency panchromatic dye-sensitized solar cells

    PubMed Central

    DANG, XIANGNAN; QI, JIFA; KLUG, MATTHEW T.; CHEN, PO-YEN; YUN, DONG SOO; FANG, NICHOLAS X.; HAMMOND, PAULA T.; BELCHER, ANGELA M.

    2014-01-01

    In photovoltaic devices, light harvesting (LH) and carrier collection have opposite relations with the thickness of the photoactive layer, which imposes a fundamental compromise for the power conversion efficiency (PCE). Unbalanced LH at different wavelengths further reduces the achievable PCE. Here, we report a novel approach to broadband balanced LH and panchromatic solar energy conversion using multiple-core-shell structured oxide-metal-oxide plasmonic nanoparticles. These nanoparticles feature tunable localized surface plasmon resonance frequencies and the required thermal stability during device fabrication. By simply blending the plasmonic nanoparticles with available photoactive materials, the broadband LH of practical photovoltaic devices can be significantly enhanced. We demonstrate a panchromatic dye-sensitized solar cell with an increased PCE from 8.3% to 10.8%, mainly through plasmon-enhanced photo-absorption in the otherwise less harvested region of solar spectrum. This general and simple strategy also highlights easy fabrication, and may benefit solar cells using other photo-absorbers or other types of solar-harvesting devices. PMID:23339821

  20. Carbonate Doping in TiO2 Microsphere: The Key Parameter Influencing Others for Efficient Dye Sensitized Solar Cell

    PubMed Central

    Seddigi, Zaki S.; Ahmed, Saleh A.; Sardar, Samim; Pal, Samir Kumar

    2016-01-01

    Four key parameters namely light trapping, density of light harvesting centre, photoinduced electron injection and electron transport without self-recombination are universally important across all kinds of solar cells. In the present study, we have considered the parameters in the context of a model Dye Sensitized Solar Cell (DSSC). Our experimental studies reveal that carbonate doping of TiO2 mesoporous microspheres (doped MS) makes positive influence to all the above mentioned key parameters responsible for the enhanced solar cell efficiency. A simple method has been employed to synthesize the doped MS for the photoanode of a N719 (ruthenium dye)-based DSSC. A detail electron microscopy has been used to characterize the change in morphology of the MS upon doping. The optical absorption spectrum of the doped MS reveals significant shift of TiO2 (compared to that of the MS without doping) towards maximum solar radiance (~500 nm) and the excellent scattering in the entire absorption band of the sensitizing dye (N719). Finally, and most importantly, for the first time we have demonstrated that the solar cells with doped MS offers better efficiency (7.6%) in light harvesting compared to MS without doping (5.2%) and also reveal minimum self recombination of photoelectrons in the redox chain. PMID:26984765

  1. First principles study of organic sensitizers for dye sensitized solar cells: effects of anchoring groups on optoelectronic properties and dye aggregation.

    PubMed

    Nachimuthu, Santhanamoorthi; Chen, Wei-Chieh; Leggesse, Ermias Girma; Jiang, Jyh-Chiang

    2016-01-14

    We have designed a new set of D-π-A type organic dye sensitizers with different acceptor and anchoring groups, and systematically investigated their optoelectronic properties for efficient dye sensitized solar cell applications. Particularly, we have focused on the effects of anchoring groups on the dye aggregation phenomenon. TDDFT results indicate that the dyes with CSSH anchoring groups exhibit improved optoelectronic properties compared to other dyes. Further, molecular dynamics simulations have been performed to describe the formation of dye aggregation due to intermolecular hydrogen bonding. The observed results indicate that dyes with CSSH anchoring groups are less prone to aggregate because of their very weak intermolecular interactions.

  2. Structural and optical properties of Purpurin for dye-sensitized solar cells.

    PubMed

    Ranjitha, S; Rajarajan, G; Gnanendra, T S; Anbarasan, P M; Aroulmoji, V

    2015-10-01

    In this work, we reported a combined experimental and theoretical study on molecular structure, vibrational spectra and Homo-Lumo analysis of Purpurin and TiO2/Purpurin. The geometries, electronic structures, molecular orbital analysis of natural dye sensitizer Purpurin were studied based on density functional theory (DFT) using the hybrid functional B3LYP. Fourier transform infrared (FT-IR) and FT-Raman spectra have been recorded and extensive spectroscopic investigations have been carried out on Purpurin. The optimized geometries, wave number and intensity of the vibrational bands of Purpurin have been calculated using density functional level of theory (DFT/B3LYP) employing 6-311G (d,p) basis set. Based on the comparison between calculated and experimental results, assignments of the fundamental vibrational modes are examined. Features of the electronic absorption spectrum in the visible and near-UV regions were assigned based on TD-DFT calculations. The calculated results suggest that the three excited states with the lowest excited energies in 1,2,4, trihydroxy 9-10 anthraquinone was due to photo-induced electron transfer processes. Frontier molecular orbitals (FMO), LUMO, HOMO, and energy gap, of these dyes have been analyzed to show their effect on the process of electron injection and dye regeneration. Interaction between HOMO and LUMO of Purpurin are investigated to understand the recombination process and charge transfer process involving these dyes. We also performed analysis of I-V characteristics to investigate the role of charge transfer and the stability of the dye molecule. PMID:26037779

  3. Anatase TiO(2) nanosheets with exposed (001) facets: improved photoelectric conversion efficiency in dye-sensitized solar cells.

    PubMed

    Yu, Jiaguo; Fan, Jiajie; Lv, Kangle

    2010-10-01

    Dye-sensitized solar cells (DSSCs) are fabricated based on anatase TiO(2) nanosheets (TiO(2)-NSs) with exposed {001} facets, which were obtained by a simple one-pot hydrothermal route using HF as a morphology controlling agent and Ti(OC(4)H(9))(4) as precursor. The prepared samples were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, UV-vis absorption spectroscopy and N(2) adsorption-desorption isotherms. The photoelectric conversion performances of TiO(2)-NSs solar cells are also compared with TiO(2) nanoparticles (TiO(2)-NPs) and commercial-grade Degussa P25 TiO(2) nanoparticle (P25) solar cells at the same film thickness, and their photoelectric conversion efficiencies (η) are 4.56, 4.24 and 3.64%, respectively. The enhanced performance of the TiO(2)-NS solar cell is due to their good crystallization, high pore volume, large particle size and enhanced light scattering. The prepared TiO(2) nanosheet film electrode should also find wide-ranging potential applications in various fields including photocatalysis, catalysis, electrochemistry, separation, purification and so on.

  4. Anatase TiO2 nanosheets with exposed (001) facets: improved photoelectric conversion efficiency in dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Yu, Jiaguo; Fan, Jiajie; Lv, Kangle

    2010-10-01

    Dye-sensitized solar cells (DSSCs) are fabricated based on anatase TiO2 nanosheets (TiO2-NSs) with exposed {001} facets, which were obtained by a simple one-pot hydrothermal route using HF as a morphology controlling agent and Ti(OC4H9)4 as precursor. The prepared samples were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, UV-vis absorption spectroscopy and N2 adsorption-desorption isotherms. The photoelectric conversion performances of TiO2-NSs solar cells are also compared with TiO2 nanoparticles (TiO2-NPs) and commercial-grade Degussa P25 TiO2 nanoparticle (P25) solar cells at the same film thickness, and their photoelectric conversion efficiencies (η) are 4.56, 4.24 and 3.64%, respectively. The enhanced performance of the TiO2-NS solar cell is due to their good crystallization, high pore volume, large particle size and enhanced light scattering. The prepared TiO2 nanosheet film electrode should also find wide-ranging potential applications in various fields including photocatalysis, catalysis, electrochemistry, separation, purification and so on.

  5. Correction: Dye adsorption mechanisms in TiO2 films, and their effects on the photodynamic and photovoltaic properties in dye-sensitized solar cells.

    PubMed

    Hwang, Kyung-Jun; Shim, Wang-Geun; Kim, Dajung; An, Jongdeok; Im, Chan; Kim, Youngjin; Kim, Gunwoo; Choi, Chulmin; Kang, Sang Ook; Cho, Dae Won

    2016-02-21

    Correction for 'Dye adsorption mechanisms in TiO2 films, and their effects on the photodynamic and photovoltaic properties in dye-sensitized solar cells' by Kyung-Jun Hwang et al., Phys. Chem. Chem. Phys., 2015, 17, 21974-21981.

  6. Pulse-reverse electrodeposition of transparent nickel phosphide film with porous nanospheres as a cost-effective counter electrode for dye-sensitized solar cells.

    PubMed

    Wu, Mao-Sung; Wu, Jia-Fang

    2013-12-01

    A Ni2P nanolayer with porous nanospheres was directly coated on fluorine-doped tin oxide glass by pulse-reverse deposition as a low-cost counter electrode catalyst for dye-sensitized solar cells, and the photoelectron conversion efficiency of the cell was increased to 7.32% by using a porous nanosphere catalyst due to the significantly improved ion transport.

  7. Theoretical investigation of self-assembled donor-acceptor phthalocyanine complexes and their application in dye-sensitized solar cells.

    PubMed

    Yu, Lijuan; Lin, Li; Liu, Yuwen; Li, Renjie

    2015-06-01

    A theoretical investigation of self-assembled donor-acceptor dyads (ZnPca, ZnPcb and ZnPcc) formed by axial coordination of zinc phthalocyanines appended with 4-carboxyl pyridine has been conducted with the density functional theory (DFT) method and time-dependent DFT (TD-DFT) calculations. A comparison between the molecular structures, atomic charges, molecular orbitals, UV-vis spectra and infrared (IR) spectra has been studied. Further, as sensitizers for the TiO2-based dye-sensitized solar cells, the photovoltaic performances have been investigated. The ZnPcc-sensitized solar cell exhibits a higher conversion efficiency than the ZnPcb and ZnPca-sensitized ones under AM 1.5G solar irradiation, while the ZnPca-sensitized cell performs the poorest due to the lack of peripheral substituents (n-butyoxyl groups) which can be confirmed by the result of the theoretical research. It shows that the directionality of charge transfer in the self-assembled donor-acceptor dyads is important and benefit for the efficiency of the DSSC.

  8. Organic sensitizers featuring a planar indeno[1,2-b]-thiophene for efficient dye-sensitized solar cells.

    PubMed

    Lim, Kimin; Ju, Myung Jong; Song, Juman; Choi, In Taek; Do, Kwangsuk; Choi, Hyeju; Song, Kihyung; Kim, Hwan Kyu; Ko, Jaejung

    2013-08-01

    An efficient organic sensitizer (JK-306) featuring a planar indeno[1,2-b]thiophene as the π-linker of a bridging unit for dye-sensitized solar cells (DSSCs) was synthesized. The sensitizer had a strong molar absorption coefficient and a red-shifted absorption band compared with JK-305, which resulted in a significant increase in the short-circuit photocurrent density. We incorporated a highly congested bulky amino group into the 2',4'-dihexyloxybiphenyl-4-yl moiety, an electron donor, to diminish the charge recombination and to prevent aggregation of the sensitizer. Under standard AM 1.5G solar conditions, JK-306-sensitized cells in the presence of co-adsorbents chenodeoxycholic acid (CDCA) and 4-[bis(9,9-dimethyl-9H-fluoren-2-yl)amino]benzoic acid (HC-A), which afforded an overall conversion efficiency of 8.37% and 8.52%, respectively. Upon changing the I(-) /I3 (-) electrolyte to the Co(II) /Co(III) redox couple, the cell gave rise to a significantly improved conversion efficiency of 10.02% with the multifunctional HC-A, which is one of the highest values reported for DSSCs with a cobalt-based electrolyte. Furthermore, the JK-306-based solar cell with a polymer gel electrolyte revealed a high conversion efficiency of 7.61%, which is one of the highest values for cells based on organic sensitizers.

  9. Excitation energy transfer from long-persistent phosphors for enhancing power conversion of dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Puntambekar, Ajinkya; Chakrapani, Vidhya

    2016-06-01

    Incorporation of inorganic phosphors to improve the spectral absorption range of a dye-sensitized solar cell (DSSC) is a promising strategy to enhance efficiency beyond 15%. However, only marginal improvements have been achieved so far, which is mainly due to the use of nonoptimized device architecture and the lack of understanding of the energy transfer mechanism. Here we report results of DSSCs employing long-persistence phosphor coupled to the sensitizing dye. Detailed time-resolved photoluminescence measurements suggest that excitation energy is transferred radiatively as opposed to Förster resonance energy transfer. As a result of efficient energy transfer, large-area solar cells show a 63% increase in the photocurrent density along with a 54% increase in power conversion efficiency. In addition, the device works as a "nighttime solar cell" with generation of 52 μ W c m-2 power density in the dark. Under short-circuit conditions, the device can output 300 mV for 30 h in the dark.

  10. Pulsed microwave heating method for preparation of dye-sensitized solar cells for greener, faster, cheaper production of photovoltaic materials

    NASA Astrophysics Data System (ADS)

    Murphy, Clifford B.; Cotta, Robert; Blais, Timothy; Hall, Charles B.

    2015-05-01

    Microwave heating methods are very popular for developing chemical syntheses that are achieved much more rapidly or with less solvent than via conventional heating methods. Their application to solar cell development has been primarily in developing improvements in the synthesis of dyes and curing of polymer substrates, but not in assisting the photoanode construction of dye-sensitized solar cells. Microwave heating of conducting substrates can lead to arcing of electricity in the reactor, which in turn, can lead to extensive degradation or complete destruction of the photoanode. Here we present our work in applying a pulsed microwave heating method that affords quicker dye deposition times in comparison to conventional heating (μw 40 min, conventional 60 min) with similar dye concentrations as characterized by UV-Vis absorbance, contact angle measurements, and cyclic voltammetry. Our photoanodes are constructed with anatase TiO2 cured onto FTO glass, and deposition of the N719 ruthenium dye either directly to the TiO2 layer or through amide bond formation to a silane layer that has been deposited on the TiO2 layer. Modest improvements in the solar energy conversion efficiency are shown through the microwave method in comparison to conventional heating (μw 0.78% vs. conventional 0.25% reported by K. Szpakolski, et. Al. Polyhedron, 2013, 52, 719-732.)

  11. Counter electrodes from polymorphic platinum-nickel hollow alloys for high-efficiency dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Wang, Jing; Tang, Qunwei; He, Benlin; Yang, Peizhi

    2016-10-01

    Precious platinum counter electrode (CE) has been an economic burden for future commercialization of dye-sensitized solar cells (DSSCs). Low-platinum alloy CE catalysts are promising in bringing down the solar cell cost without reducing photovoltaic performances. We present here a facile strategy of fabricating ZnO nanorods assisted platinum-nickel (PtNi) alloy microtube CEs for liquid-junction DSSCs. By adjusting the concentration of zinc precursors, the ZnO nanostructures and therefore PtNi alloys are optimized to maximize the electrocatalytic behaviors toward triiodide reduction reaction. The maximal power conversion efficiency is determined as high as 8.43% for liquid-junction DSSC device with alloyed PtNi microtube CE synthesized at 75 mM Zn(NO3)2 aqueous solution, yielding a 32.8% enhancement in cell efficiency in comparison with the solar cell from pristine platinum electrode. Moreover, the dissolution resistance and charge-transfer ability toward redox couples have also been markedly enhanced due to competitive dissolution reactions and alloyed effects.

  12. Performance optimization in dye-sensitized solar cells with β-NaYF4:Er3+/Yb3+ and graphene multi-functional layer hybrid composite photoanodes

    NASA Astrophysics Data System (ADS)

    Luoshan, Mengdai; Li, Meiya; Liu, Xiaolian; Guo, Kaimo; Bai, Lihua; Zhu, Yongdan; Sun, Beilei; Zhao, Xingzhong

    2015-08-01

    The β-NaYF4:Er3+/Yb3+ hexagonal submicro-prisms coated with SiO2 forming core-shell structures (NYFYE@SiO2) and graphene oxide have been synthesized via a hydrothermal route. These NYFYE@SiO2 prisms and graphene were both introduced into TiO2 nanocrystalline films to form multi-functional-layers hybrid composite photoanodes and their dye-sensitized solar cells (DSSCs). The influence of various hybrid architectures of the composite photoanodes on the performances of the photoanodes and DSSCs were explored. Studies revealed that the graphene doping obviously increased the dye absorbed in the photoanode, the short-circuit current density (Jsc) and photoelectric conversion efficiency (η) of the DSSC. The adding of the NYFYE@SiO2 prisms significantly increased the light scattering and near-infrared light harvesting of the photoelectrode, among which the SiO2 coating layer on the prisms played an important role in reducing the photoelectron recombination and thus increasing the Jsc of the DSSC. The Jsc and η of the DSSC were significantly enhanced due to the complementary role between the UC of the NYFYE@SiO2 and the graphene. The optimal properties with a Jsc of 14.63 mA/cm2 and η of 7.16% are obtained in the DSSC with the codoped composite photoanode, increasing significantly by 21.5% and 25.6%, respectively, in comparison with those of the DSSC with pure TiO2 photoanode. Our studies demonstrated that codoping in photoanode with materials of complementary functions is an effective way to improve the performance of DSSCs.

  13. Structural color-tunable mesoporous bragg stack layers based on graft copolymer self-assembly for high-efficiency solid-state dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Lee, Chang Soo; Park, Jung Tae; Kim, Jong Hak

    2016-08-01

    We present a facile fabrication route for structural color-tunable mesoporous Bragg stack (BS) layers based on the self-assembly of a cost-effective graft copolymer. The mesoporous BS layers are prepared through the alternating deposition of organized mesoporous-TiO2 (OM-TiO2) and -SiO2 (OM-SiO2) films on the non-conducting side of the counter electrode in dye-sensitized solar cells (DSSCs). The OM layers with controlled porosity, pore size, and refractive index are templated with amphiphilic graft copolymers consisting of poly(vinyl chloride) backbones and poly(oxyethylene methacrylate) side chains, i.e., PVC-g-POEM. The morphology and properties of the structural color-tunable mesoporous BS-functionalized electrodes are characterized using energy filtered transmission electron microscopy (EF-TEM), field emission-scanning electron microscopy (FE-SEM), spectroscopic ellipsometry, and reflectance spectroscopy. The solid-state DSSCs (ssDSSCs) based on a structural color-tunable mesoporous BS counter electrode with a single-component solid electrolyte show an energy conversion efficiency (η) of 7.1%, which is much greater than that of conventional nanocrystalline TiO2-based cells and one of the highest values for N719 dye-based ssDSSCs. The enhancement of η is due to the enhancement of current density (Jsc), attributed to the improved light harvesting properties without considerable decrease in fill factor (FF) or open-circuit voltage (Voc), as confirmed by incident photon-to-electron conversion efficiency (IPCE) and electrochemical impedance spectroscopy (EIS).

  14. Enhanced electron collection in TiO{sub 2} nanoparticle-based dye-sensitized solar cells by an array of metal micropillars on a planar fluorinated tin oxide anode.

    SciTech Connect

    Yang, Z.; Xu, T.; Gao, S.; Welp, U.; Kwok, W.-K.; Materials Science Division; Northern Illinois Univ.

    2010-01-01

    Charge collection efficiency exhibits a strong influence on the overall efficiency of nanocrystalline dye-sensitized solar cells. It highly depends on the quality of the TiO{sub 2} nanoparticulate layer in the photoanode, and hence most efforts have been directed on the improvement and deliberate optimization of the quality the TiO{sub 2} nanocrystalline layer. In this work, we aim to reduce the electron collection distance between the place of origin in the TiO{sub 2} layer to the electron-collecting TCO anode as an alternative way to enhance the charge collection efficiency. We use an array of metal micropillars on fluorine-doped tin oxide (FTO) as the collecting anode. Under the same conditions, the Ni micropillar-on-FTO-based dye-sensitized solar cells (DSSCs) exhibit a remarkably enhanced current density, which is approximately 1.8 times greater compared with the bare FTO-based DSSCs. Electron transport was investigated using the electrochemical impedance spectroscopy technique. Our results reveal that the electron collection time in Ni micropillar-on-FTO-based DSSCs is much shorter than that of bare FTO-based DSSCs, indicating faster electron collection due to the Ni micropillars buried in TiO{sub 2} nanoparticulate layer that serve as electron transport shortcuts. As a result, the charge collection efficiency was enhanced by 15?20% with respect to that of the bare FTO-based DSSCs. Consequently, the overall energy conversion efficiency was found to increase from 2.6% in bare FTO-based DSSCs to 4.8% in Ni micropillar-on-FTO-based DSSCs for a 6 {micro}m-thick TiO{sub 2} NP film.

  15. Theoretical design and screening of alkyne bridged triphenyl zinc porphyrins as sensitizer candidates for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Zhang, Xianxi; Chen, Qianqian; Sun, Huafei; Pan, Tingting; Hu, Guiqi; Ma, Ruimin; Dou, Jianmin; Li, Dacheng; Pan, Xu

    2014-01-01

    Alkyne bridged porphyrins have been proved very promising sensitizers for dye-sensitized solar cells (DSSCs) with the highest photo-to-electric conversion efficiencies of 11.9% solely and 12.3% co-sensitized with other sensitizers achieved. Developing better porphyrin sensitizers with wider electronic absorption spectra to further improve the efficiencies of corresponding solar cells is still of great significance for the application of DSSCs. A series of triphenyl zinc porphyrins (ZnTriPP) differing in the nature of a pendant acceptor group and the conjugated bridge between the porphyrin nucleus and the acceptor unit were modeled and their electronic and spectral properties calculated using density functional theory. As compared with each other and the experimental results of the compounds used in DSSCs previously, the molecules with a relatively longer conjugative linker and a strong electron-withdrawing group such as cyanide adjacent to the carboxyl acid group seem to provide wider electronic absorption spectra and higher photo-to-electric conversion efficiencies. The dye candidates ZnTriPPE, ZnTriPPM, ZnTriPPQ, ZnTriPPR and ZnTriPPS designed in the current work were found promising to provide comparable photo-to-electric conversion efficiencies to the record 11.9% of the alkyne bridged porphyrin sensitizer YD2-o-C8 reported previously.

  16. Effect of Al Doping on Performance of CuGaO2 p-Type Dye-Sensitized Solar Cells

    NASA Astrophysics Data System (ADS)

    Ursu, D.; Vaszilcsin, N.; Bănica, R.; Miclau, M.

    2016-01-01

    The p-type semiconductor Cu(I)-based delafossite transparent conducting oxides are good candidates to be used as hole collectors in dye-sensitized solar cells. The Al-doped CuGaO2 has been synthesized by hydrothermal method and its properties have been investigated as cathode elements in ruthenium dye N719-sensitized solar cells. The photocurrent density ( J sc) and the open-circuit voltage ( V oc) for 5% Al-doped CuGaO2 microparticles using N719 dye were approximately two times higher than undoped CuGaO2 microparticles. The integration of aluminum dopants in the delafossite structure improves the photovoltaic performance of CuGaO2 thin films, due to the excellent optical transparency of CuGaO2 in the visible range as well as the improved electrical conductivity caused by the apparition of the intrinsic acceptor defect associate (Al Cu •• 2O i ″ )″ with tetrahedrally coordinated Al on the Cu-site.

  17. Effect of swift heavy ion (SHI) irradiation on transparent conducting oxide electrodes for dye-sensitized solar cell applications

    NASA Astrophysics Data System (ADS)

    Singh, Hemant Kr.; Avasthi, D. K.; Aggarwal, Shruti

    2015-06-01

    Transparent conducting oxides (TCOs) are used as electrodes in dye-sensitized solar cells (DSSCs) because of their properties such as high transmittance and low resistivity. In the present work, the effects of swift heavy ion (SHI) irradiation on various types of TCOs are presented. The objective of this study is to investigate the effect of SHI on TCOs. For the present study, three different types of TCOs are considered, namely, (a) FTO (fluorine-doped tin oxide, SnO2:F) on a Nippon glass substrate, (b) ITO (indium tin oxide, In2O3:Sn) coated on polyethylene terephthalate (PET) on a Corning glass substrate, and (c) ITO on a Corning glass substrate. These films are irradiated with 120 MeV Ag+9 ions at fluences ranging from 3.0 × 1011 ions/cm2 to 3.0 × 1013 ions/cm2. The structural, morphological, optical and electrical properties are studied via X-ray diffraction (XRD), atomic force microscopy (AFM), UV-Vis absorption spectroscopy and four-probe resistivity measurements, respectively. The ITO-PET electrode is found to exhibit superior conductivity and transmittance properties in comparison with the others after irradiation and, therefore, to be the most suitable for solar cell applications.

  18. Ultrafast charge separation dynamics in opaque, operational dye-sensitized solar cells revealed by femtosecond diffuse reflectance spectroscopy

    NASA Astrophysics Data System (ADS)

    Ghadiri, Elham; Zakeeruddin, Shaik M.; Hagfeldt, Anders; Grätzel, Michael; Moser, Jacques-E.

    2016-04-01

    Efficient dye-sensitized solar cells are based on highly diffusive mesoscopic layers that render these devices opaque and unsuitable for ultrafast transient absorption spectroscopy measurements in transmission mode. We developed a novel sub-200 femtosecond time-resolved diffuse reflectance spectroscopy scheme combined with potentiostatic control to study various solar cells in fully operational condition. We studied performance optimized devices based on liquid redox electrolytes and opaque TiO2 films, as well as other morphologies, such as TiO2 fibers and nanotubes. Charge injection from the Z907 dye in all TiO2 morphologies was observed to take place in the sub-200 fs time scale. The kinetics of electron-hole back recombination has features in the picosecond to nanosecond time scale. This observation is significantly different from what was reported in the literature where the electron-hole back recombination for transparent films of small particles is generally accepted to occur on a longer time scale of microseconds. The kinetics of the ultrafast electron injection remained unchanged for voltages between +500 mV and -690 mV, where the injection yield eventually drops steeply. The primary charge separation in Y123 organic dye based devices was clearly slower occurring in two picoseconds and no kinetic component on the shorter femtosecond time scale was recorded.

  19. Porous (001)-faceted anatase TiO2 nanorice thin film for efficient dye-sensitized solar cell

    NASA Astrophysics Data System (ADS)

    Shah, Athar Ali; Umar, Akrajas Ali; Mat Salleh, Muhamad

    2016-01-01

    Anatase TiO2 structures with nanorice-like morphology and high exposure of (001) facet has been successfully synthesized on an ITO surface using ammonium Hexafluoro Titanate and Hexamethylenetetramine as precursor and capping agent, respectively, under a microwave-assisted liquid-phase deposition method. These anatase TiO2 nanoparticles were prepared within five minutes of reaction time by utilizing an inverter microwave system at a normal atmospheric pressure. The morphology and the size (approximately from 6 to 70 nm) of these nanostructures can be controlled. Homogenous, porous, 5.64 ± 0.002 μm thick layer of spongy-nanorice with facets (101) and (001) was grown on ITO substrate and used as a photo-anode in a dye-sensitized solar cell (DSSC). This solar cell device has emerged out with 4.05 ± 0.10% power conversion efficiency (PCE) and 72% of incident photon-to-current efficiency (IPCE) under AM1.5 G illumination.

  20. Bifacial dye-sensitized solar cells: A strategy to enhance overall efficiency based on transparent polyaniline electrode

    PubMed Central

    Wu, Jihuai; Li, Yan; Tang, Qunwei; Yue, Gentian; Lin, Jianming; Huang, Miaoliang; Meng, Lijian

    2014-01-01

    Dye-sensitized solar cell (DSSC) is a promising solution to global energy and environmental problems because of its clean, low-cost, high efficiency, good durability, and easy fabrication. However, enhancing the efficiency of the DSSC still is an important issue. Here we devise a bifacial DSSC based on a transparent polyaniline (PANI) counter electrode (CE). Owing to the sunlight irradiation simultaneously from the front and the rear sides, more dye molecules are excited and more carriers are generated, which results in the enhancement of short-circuit current density and therefore overall conversion efficiency. The photoelectric properties of PANI can be improved by modifying with 4-aminothiophenol (4-ATP). The bifacial DSSC with 4-ATP/PANI CE achieves a light-to-electric energy conversion efficiency of 8.35%, which is increased by ~24.6% compared to the DSSC irradiated from the front only. This new concept along with promising results provides a new approach for enhancing the photovoltaic performances of solar cells. PMID:24504117