Correlation between dispersion properties of TiO2 colloidal sols and photoelectric characteristics of TiO2 films

摘要

TiO_2 film for use as dye-sensitized solar cell was prepared using the TiO_2 colloidal sols(unpeptized sol and peptized sol).The optical properties and photocurrent-voltage characteristics of the resultant films were investigated.The optical transmittance of TiO_2 thin film prepared from the peptized colloidal sol was over 90%,while that of TiO_2 film from the unpeptized sol was under 80%.The TiO2 photoelectrode prepared from the peptized colloidal sol showed low photoelectric conversion efficiency(eta),1.30%,whereas the efficiency of photoelectrode from the unpeptized sol was 2.21%.The high optical transmittance and low conversion efficiency of TiO_2 film from the peptized sol are discussed in terms of dense microstructure due to the drying nature of well-dispersed colloidal sol.