Quasi-solid-state cells

Wang P, Zakeeruddin SM, Moser JE, Nazeeruddin MK, Sekiguchi T, Gratzel M (2003) A stable-quasi-solid state dye-sensitized solar cell with amphiphilic ruthenium sensitizer and polymer gel electrolyte. Nature Mater 2 402-406... 

Kubo, W. et al.. Quasi-solid-state dye-sensitized solar cells using room temperature molten salts and a low molecular weight gelator, Chem. Commun., 374, 2002. 

The use of quasi-solid-state electrolytes usually reaches the goal of a superior thermal stability with respect to liquid electrolytes cells can survive prolonged periods (accelerated aging of 1000 h) at relatively high temperatures (55-80°C) under... 

Another type of lithium solid state cell which reached the quasi-commercial stage was developed in the mid-1980s by Eveready. This cell used a vitreous inorganic electrolyte formed by a mixture of Lil and Li8P4Oo,25S 13.75. This solid electrolyte had a reasonably high conductivity which allowed cell operation at ambient temperatures. A disadvantage was its high reactivity which imposed the use of severe fabrication controls (e.g. assembly in a strictly moisture-free environment). 

Quasi-solid state dye-sensitized solar cells (DSCs) have been constructed using a new polymeric ionic fluid as the electrolyte.119 The electrolyte was synthesized by the sol-gel route using MTMSPI+I as the precursor that was made by derivatizing methylimidazolium with triethyoxysilane. Condensation of this material in the presence of formic acid and in the absence of water led to Si-O-Si-O-type polymerization and formation of a polysilsesquioxane-type structure. When this material was mixed with iodine, it served as a redox electrolyte for DSCs. The DSCs made this way are robust and easy to assemble but their efficiency of 3.1% is relatively low. However, possible improvement lies in modification of the organic groups attached to the polysilsesquioxane backbone. 

DSSCs prepared from this quasi-solid-state ionic liquid gel were stable under light at 60 °C for 1,000 h and had an efficiency of 6.3 % under simulated AM 1.5 frill sunlight, and the gelator had no influence on the performance of the solar cell. It was proposed that, after complete dissolution of the organogelator at elevated temperatures, the gelator molecules built up nanoscale fibrils due to the formation of hydrogen bonds by the amide and urea units and thus formed a three-dimensional network. This led to gelation of the ionic liquid mixture and hindered flow of the liquid. 

Li M, Feng S, Fang S, Xiao X, Li X, Zhou X, Lin Y (2007) Quasi-solid state dye-sensitized solar cells based on p3uidine or imidazole containing copolymer chemically crosslinked gel... 

A few research conducted to fabricate the Electrospun PVDF-HFP membrane by electrospinning process from asolutionofpoly(vinylidenefluoride-cohexafluoropropylene) in a mixture of acetone/N, N-dimethylacetamide to encapsulate electrolyte solution [45, 46], Although the solar eneigy-to electricity conversion efficiency of the quasi-solid-state solar cells with the electrospun PVDF-HFP membrane was slightly lower than the value obtained from the conventional liquid electrolyte solar cells, this cell exhibited better long-term durability because of the prevention of electrolyte solution leakage. 

Wang Zakeeruddin SM. Comte Exnarl. Gratzel M. Gelation of Ionic Liquid-based Electrolytes with Silica Nanoparticles for Quasi-solid-state Dye-sensitized Solar Cells, J. American Chemical society 2003,125, 1166-1167. 

Balraju P, Kumar M, Deol YS et al (2010) Photovoltaic performance of quasi-solid state dye sensitized solar cells based on perylene dye and modified Ti02 photo-electrode. Synth Met... 

Wang, P., Zakeeruddin, S.M., Comte, P., Exnar, I., and Graetzel, M. (2003) Gelation of ionic liquid-based electrolytes with silica nanoparticles for quasi-solid-state dye-sensitized solar cells. /. Am. Chem. Soc., 125, 1166-1167. 

Many groups have focused on the substitution of the liquid electrolyte by solid or gel electrolytes, which could aid in reducing costs and make assembly of dye-sensitized solar cells easier. The development of solid-state electrolytes is generally divided into two main parts quasi-solid-state electrolyte and solid-state electrolyte. 

An electrospun membrane was prepared from a 16 wt% solution of poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) in a mixture of acetone/AA -dimethylacetamide (7 3 wt%) at an applied voltage of 12 kV [90]. The electrospun membrane was then activated by immersing it in 0.6 M l-hexyl-2,3-dimethylimidazolium iodide, 0.1 M Lil, 0.05 M I2, and 0.5 M 4-tert-butylpyridine in ethylene carbonate/propylene carbonate (1 1 wt%) to obtain the corresponding membrane electrolyte with an ionic conductivity of 10 S cm at 25 °C. On the basis of this electrospun membrane electrolyte, quasi-solid-state dye-sensitized solar cells were fabricated, which showed an open-circuit voltage of 0.76 V, a All factor of 0.62, and a short-circuit current density of 15.57 mA cm at an incident... 

Song MY, Ahn YR, Jo SM, Kim DY, Ahn JP (2005) T102 single-crystalline nanorod electrode for quasi-solid-state dye-sensitized solar cells. Appl Phys Lett 87(11) 113113... 

M. Biancardo, K. West, and F. G. Krebs. 2007. Quasi-solid-state dye-sensitized solar cells Pt and PEDOT PSS counter electrodes applied to gel electrolyte assemblies. / Photochem Photobiol A 187 395 01. 

Some authors reported the stability of DSSC assembled with polymer electrolytes with different compositions and related this behavior to the properties of the electrolyte. For example, solar cells were assembled with electrolytes combining the ionic liquid l-methyl-3-propylimidazolium iodine and PEO, poly(propylene oxide) or the copolymer poly(ethylene oxide)-block-poly(propylene oxide)-block-poly(ethylene oxide). After introducing less than 10 wt% of the polyether into the liquid electrolyte, the parameters of these quasi-solid state solar cells were still comparable to those of the liquid photochemical cells. It was believed that the polymer can contribute to the maintenance of the efficiency of the solar cells by holding the organic solvent. All devices were sealed with paraffin wax. The cell assembled with liquid electrolyte lost half of the conversion efficiency after 5 days, while the cells fabricated with the polyether-electrolytes had... 

Biancardo and co-workers assembled a semitransparent quasi-solid state dye-sensitized solar module connecting in series solar cells assembled with a gel electrolyte. Each individual cell presented an efficiency of 1% under 100 mW cm" . The efficiency of the whole module composed 23 cells (active area of 625 cm ) reached 0.3%. The authors claimed that, although the efficiency was higher for modules assembled with liquid electrolytes, the use of the gel electrolyte clearly improved the performance of the cells after 1 month, leading to devices with extended lifetime. ... 

STATHATOS, E., LiANOs. p., suRCAVUK, A., OREL, B., Optimization of a quasi-solid-state dye-sensitized photoelectrochemical solar cell employing a ureasil/sulfo-lane gel electrolyte, Aifv. Funct. Mater., 2004,14,45-8. 

An efficient organogelator for ionic liquids to prep>are stable quasi-solid-state dye-sensitized solar cells. J. Mater. Chem., 16,2978-2983. 

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