Non‐Corrosive, Non‐Absorbing Organic Redox Couple for Dye‐Sensitized Solar Cells

A new colorless electrolyte containing an organic redox couple, tetramethylthiourea (TMTU) and its oxidized dimer tetramethylformaminium disulfide dication ([TMFDS](2+)), is applied to dye-sensitized solar cells (DSCs). Advantages of this redox couple include its non-corrosive nature, low cost, and easy handling. More impressively, it operates well with carbon electrodes. The DSCs fabricated with a lab-made HCS-CB carbon counter-electrode can present up to 3.1% power conversion efficiency under AM 1.5 illumination of 100 mW.cm(-2) and 4.5% under weaker light intensities. This result distinctly outperforms the identical DSCs with a Pt electrode. Corrosive experiments reveal that Al and stainless steel (SS) sheets are stable in the [TMFDS](2+)/TMTU-based electrolyte. Its electrochemical impedance spectrum (EIS) is used to evaluate the influence of different counter-electrodes on the cell performance, and preliminary investigations reveal that carbon electrodes with large surface areas and ideal corrosion-inertness toward the sulfur-containing [TMFDS](2+)/TMTU redox couple exhibit promise for application in iodine-free DSCs.

[1]  Chi-Chao Wan,et al.  Poly(N-vinyl-2-pyrrolidone)-capped platinum nanoclusters on indium-tin oxide glass as counterelectrode for dye-sensitized solar cells , 2006 .

[2]  Timothy D Heidel,et al.  High-Efficiency Organic Solar Concentrators for Photovoltaics , 2008, Science.

[3]  Xiaoming Huang,et al.  Application of carbon counterelectrode on CdS quantum dot-sensitized solar cells (QDSSCs) , 2010 .

[4]  Michael Grätzel,et al.  Solar energy conversion by dye-sensitized photovoltaic cells. , 2005, Inorganic chemistry.

[5]  J. Bisquert.  Interpretation of electron diffusion coefficient in organic and inorganic semiconductors with broad distributions of states. , 2008, Physical chemistry chemical physics : PCCP.

[6]  D. Macfarlane,et al.  Rapid I-/I3 - diffusion in a molecular-plastic-crystal electrolyte for potential application in solid-state photoelectrochemical cells. , 2004, Angewandte Chemie.

[7]  Akira Fujishima,et al.  Fabrication of an efficient solid-state dye-sensitized solar cell , 2003 .

[8]  Michael Grätzel,et al.  Electrochemical studies of the Co(III)/Co(II)(dbbip)2 redox couple as a mediator for dye-sensitized nanocrystalline solar cells , 2004 .

[9]  C. M. Elliott,et al.  Efficient non-corrosive electron-transfer mediator mixtures for dye-sensitized solar cells. , 2006, Journal of the American Chemical Society.

[10]  Thomas W. Hamann,et al.  New architectures for dye-sensitized solar cells. , 2008, Chemistry.

[11]  Yanhong Luo,et al.  Application of carbon materials as counter electrodes of dye-sensitized solar cells , 2007 .

[12]  R. Tscharner,et al.  Photovoltaic technology: the case for thin-film solar cells , 1999, Science.

[13]  Michael Dürr,et al.  Tandem dye-sensitized solar cell for improved power conversion efficiencies , 2004 .

[14]  S. Haque,et al.  Photochemical energy conversion: from molecular dyads to solar cells. , 2006, Chemical communications.

[15]  Jean-François Guillemoles,et al.  Nature of Photovoltaic Action in Dye-Sensitized Solar Cells , 2000 .

[16]  W. Maier,et al.  An Iodine/Triiodide Reduction Electrocatalyst for Aqueous and Organic Media , 1997 .

[17]  Michael Dürr,et al.  Low-temperature fabrication of dye-sensitized solar cells by transfer of composite porous layers , 2005, Nature materials.

[18]  Andreas Georg,et al.  Diffusion in the electrolyte and charge-transfer reaction at the platinum electrode in dye-sensitized solar cells , 2001 .

[19]  L. Peter,et al.  Dye-sensitized nanocrystalline solar cells. , 2007, Physical chemistry chemical physics : PCCP.

[20]  Michael Grätzel,et al.  An alternative efficient redox couple for the dye-sensitized solar cell system. , 2003, Chemistry.

[21]  J. Trancik,et al.  Transparent and catalytic carbon nanotube films. , 2008, Nano letters.

[22]  N. Park,et al.  A highly efficient organic sensitizer for dye-sensitized solar cells. , 2007, Chemical communications.

[23]  H. Pettersson,et al.  The Performance and Stability of Ambient Temperature Molten Salts for Solar Cell Applications , 1996 .

[24]  Peng Wang,et al.  Charge separation and efficient light energy conversion in sensitized mesoscopic solar cells based on binary ionic liquids. , 2005, Journal of the American Chemical Society.

[25]  C. M. Elliott,et al.  Substituted polypyridine complexes of cobalt(II/III) as efficient electron-transfer mediators in dye-sensitized solar cells. , 2002, Journal of the American Chemical Society.

[26]  A. W. Addison,et al.  Conversion constants for redox potentials measured versus different reference electrodes in acetonitrile solutions at 25°C , 2000 .

[27]  T. Hino,et al.  Preparation of functionalized and non-functionalized fullerene thin films on ITO glasses and the application to a counter electrode in a dye-sensitized solar cell , 2006 .

[28]  Lars Kloo,et al.  Ionic liquid electrolytes for dye-sensitized solar cells. , 2008, Dalton transactions.

[29]  Yanhong Luo,et al.  A flexible carbon counter electrode for dye-sensitized solar cells , 2009 .

[30]  N. Papageorgiou,et al.  Counter-electrode function in nanocrystalline photoelectrochemical cell configurations , 2004 .

[31]  Michael Grätzel,et al.  Low cost photovoltaic modules based on dye sensitized nanocrystalline titanium dioxide and carbon powder , 1996 .

[32]  P. Liska,et al.  Acid-Base Equilibria of (2,2'-Bipyridyl-4,4'-dicarboxylic acid)ruthenium(II) Complexes and the Effect of Protonation on Charge-Transfer Sensitization of Nanocrystalline Titania. , 1999, Inorganic chemistry.

[33]  J. Durrant,et al.  Parameters Influencing Charge Separation in Solid‐State Dye‐Sensitized Solar Cells Using Novel Hole Conductors , 2006 .

[34]  J. Werner,et al.  Diffusion-limited transport of I- 3 through nanoporous TiO2-polymer gel networks. , 2004, The Journal of chemical physics.

[35]  S. Zakeeruddin,et al.  CoII(dbbip)22+ Complex Rivals Tri-iodide/Iodide Redox Mediator in Dye-Sensitized Photovoltaic Cells , 2001 .

[36]  Ashraful Islam,et al.  Dye-Sensitized Solar Cells with Conversion Efficiency of 11.1% , 2006 .

[37]  Helena Ribeiro,et al.  Dye-sensitized solar cells: A safe bet for the future. , 2008 .

[38]  Eiichi Abe,et al.  Flexible counter electrodes based on metal sheet and polymer film for dye-sensitized solar cells , 2005 .

[39]  Jae Kwan Lee,et al.  Molecular engineering of organic sensitizers for solar cell applications. , 2006, Journal of the American Chemical Society.

[40]  Hiroshi Matsui,et al.  100 mm × 100 mm large-sized dye sensitized solar cells , 2004 .

[41]  M. Grätzel,et al.  On the relevance of mass transport in thin layer nanocrystalline photoelectrochemical solar cells , 1996 .

[42]  Rainer Kern,et al.  A glass frit-sealed dye solar cell module with integrated series connections , 2006 .

[43]  Jaesung Song,et al.  Nanocarbon counterelectrode for dye sensitized solar cells , 2007 .

[44]  M. Grätzel,et al.  A low-cost, high-efficiency solar cell based on dye-sensitized colloidal TiO2 films , 1991, Nature.

[45]  Brian A. Gregg,et al.  The Photovoltage-Determining Mechanism in Dye-Sensitized Solar Cells , 2000 .

[46]  Monica Lira-Cantu,et al.  Influence of doped anions on poly(3,4-ethylenedioxythiophene) as hole conductors for iodine-free solid-state dye-sensitized solar cells. , 2008, Journal of the American Chemical Society.

[47]  H. Pettersson,et al.  Nanocrystalline dye‐sensitized solar cells having maximum performance , 2007 .

[48]  Adam Heller.  Conversion of Sunlight into Electrical Power and Photoassisted Electrolysis of Water in Photoelectrochemical Cells , 1981 .

[49]  Saif A. Haque,et al.  Interface Engineering for Solid‐State Dye‐Sensitized Nanocrystalline Solar Cells: The Use of Ion‐Solvating Hole‐Transporting Polymers , 2004 .

[50]  Yizhak Marcus,et al.  Ionic radii in aqueous solutions , 1983 .

[51]  Yuji Wada,et al.  Blue copper model complexes with distorted tetragonal geometry acting as effective electron-transfer mediators in dye-sensitized solar cells. , 2005, Journal of the American Chemical Society.

[52]  Yanhong Luo,et al.  Towards Optimization of Materials for Dye‐Sensitized Solar Cells , 2009 .

[53]  Qing Wang,et al.  Highly Efficient Dye-Sensitized Solar Cells Based on Carbon Black Counter Electrodes , 2006 .

[54]  Chao Zhang,et al.  Wire‐Shaped Flexible Dye‐sensitized Solar Cells , 2008 .

[55]  S. Zakeeruddin,et al.  Organic dye-sensitized ionic liquid based solar cells: remarkable enhancement in performance through molecular design of indoline sensitizers. , 2008, Angewandte Chemie.

[56]  Tsutomu Miyasaka,et al.  Low-Temperature Fabrication of Dye-Sensitized Plastic Electrodes by Electrophoretic Preparation of Mesoporous TiO2 Layers , 2004 .

[57]  G. Tulloch,et al.  Light and energy—dye solar cells for the 21st century , 2004 .

[58]  A. J. Frank,et al.  Electrons in nanostructured TiO2 solar cells: Transport, recombination and photovoltaic properties , 2004 .

[59]  D. Kuang,et al.  High Molar Extinction Coefficient Ion‐Coordinating Ruthenium Sensitizer for Efficient and Stable Mesoscopic Dye‐Sensitized Solar Cells , 2007 .

[60]  Yuh‐Lang Lee,et al.  Highly Efficient Quantum‐Dot‐Sensitized Solar Cell Based on Co‐Sensitization of CdS/CdSe , 2009 .

[61]  H. Tributsch,et al.  Dye sensitization solar cells: a critical assessment of the learning curve , 2004 .

[62]  Stephen R. Forrest,et al.  Efficient bulk heterojunction photovoltaic cells using small-molecular-weight organic thin films , 2003, Nature.

[63]  Takurou N. Murakami,et al.  The 2,2,6,6‐Tetramethyl‐1‐piperidinyloxy Radical: An Efficient, Iodine‐ Free Redox Mediator for Dye‐Sensitized Solar Cells , 2008 .

[64]  M. Grätzel.  Photovoltaic and photoelectrochemical conversion of solar energy , 2007, Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences.

[65]  Dong Yoon Lee,et al.  Portable, parallel grid dye-sensitized solar cell module prepared by screen printing , 2007 .

[66]  Hongxia Wang,et al.  Solid-state composite electrolyte LiI/3-hydroxypropionitrile/SiO2 for dye-sensitized solar cells. , 2005, Journal of the American Chemical Society.

[67]  Wenjing Hong,et al.  Transparent graphene/PEDOT–PSS composite films as counter electrodes of dye-sensitized solar cells , 2008 .

[68]  Takayuki Kitamura,et al.  Photocurrent-Determining Processes in Quasi-Solid-State Dye-Sensitized Solar Cells Using Ionic Gel Electrolytes , 2003 .

[69]  Peter Lund,et al.  Initial Performance of Dye Solar Cells on Stainless Steel Substrates , 2008 .

[70]  Juan Bisquert,et al.  Correlation between Photovoltaic Performance and Impedance Spectroscopy of Dye-Sensitized Solar Cells Based on Ionic Liquids , 2007 .

[71]  P. Liska,et al.  Fabrication of thin film dye sensitized solar cells with solar to electric power conversion efficiency over 10 , 2008 .

[72]  Peter C. Searson,et al.  Pseudohalogens for Dye-Sensitized TiO2 Photoelectrochemical Cells , 2001 .