Synthesis And Investigation Of New Electrolyte For Dye-sensitized Solar Cells

Since the development of Dye-Sensitized Solar Cells(DSSC), environment friendlyadvantages arouses scientific research enthusiasm, due to its simple manufacturing process,high conversion efficiency in theory. With the increasing development of science andtechnology, some defects of DSCC has always been proposed, such as liquid electrolyteorganic solvents volatile leakage, battery hard sealing, battery poor stability, short longevity.Beside, the low solid electrolyte conductivity, the pool and the fast attenuated conversionefficiency, the poor contact of solid electrolyte and porous film electrode also limits itspractical application.This paper is aimed the solutions of those problems in liquid electrolyte, such as organicsolvent volatile and the leakage, and poor stability of battery. And design the reasonablecompound organic solvent so as to reduce organic solvent leakage and evaporation, andeventually improve the stability of the battery performance. In this research, I3-/I-redoxelectrolyte couple system, sulfolane and3-methoxypropionitrile mixture were employed aselectrolyte solvents, and4-tert-butylpyridine as additive for preparation of liquid electrolyteusing in the DSSC. I3-/I-redox couple were characterized in electrolyte by using UV-visspectrophotometer, conductivity apparatus was introduced to characterize the electricalconductivity of electrolyte, battery monochromatic light electric conversion efficiency (IPCE)were characterized by spectrophotometer, and I-V curve of the battery and battery stabilitywere characterized by solar simulators. The influences of sulfolane on photoelectricperformances and stability of DSSC were investigated.The results showed that sulfolane and3-methoxy-propionitrile mixed solution, whichserver as the solvent of electrolyte does not affect the presence of the I3-/I-redox couple inelectrolyte redox; as the volume ratio of3-methoxypropionitrile and sulfolane is3:2，theDSSC presents optimum performance, and short current achieved to be7.58mA/cm2,photoelectric conversion efficiency reached to2.79%, and the battery showed the most stable.Compared with the sample not adding sulfone, short-circuit current improved24.5%. As electrolyte solvent, sulfolane can significantly ameliorate organic volatile leak, reduce thevolatile of3-Methoxypropionitrile and4-tert-butylpyridine, thus ensures the effectiveconcentration of redox, and greatly improved the stability of the battery performance.In solid state electrolyte, the poor contact between solid electrolyte and photoanodepresses explore a new type of organic additive. In order to improve the gap filling andelectrical contact properties between electrolyte and electrode surface, CuSCN, sulfolane,DMPII and PEDOT:PSS as solid electrolyte raw material for dye-sensitized solar cells.CuSCN powders were characterized by XRD, testing the IPCE and I-V curve of the battery tocharacterize the performance of the solid electrolyte; and the effect of sulfolane to batteryphotoelectric performance, and battery stability were also investigated.The results show that sulfolane application of p-type semiconductor CuSCN solidelectrolyte is practicable. The electrolyte can better improve the electrode contact withelectrolyte, and the sulfolane can have a certain function of modification of CuSCN crystalsurface, and it can well reduce charge compound of TiO2semiconductor-electrolyte interfaceto improve the battery stability. Adding sulfolane into solid electrolyte of DSSC, thephotoelectric performance and stability of DSSC have got some improvement. When theaddition amount of sulfolane up to0.18g and CuSCN powder to0.25g, the DSSC got betterperformances, that conclude, short circuit current density (Jsc) of3.92mA/cm2, open circuitvoltage (Voc) of0.42V, photoelectric conversion efficiency reached0.86%, and the batteryperformances show a better stable properties.