Abstract: TiO₂ films with nano-porous structures were obtained by adding the poly-ethylene glycol(PEG) in the TiO₂ colloid. Then the as-prepared films were sensitized by the trithiophene carboxylic diacid(TTDA), pentathiophene carboxylic diacid(PTDA), N3[Ru(Ⅱ)L₂(SCN)₂, L=2,2′-bipyridyl-4,4′-dicarboxylate] dye and the mixture of PTDA and N3 dye, respectively. After fabricating the films into devices, the I-V curves were determined and their photovoltaic properties were studied. The results show that the porous TiO₂ films can be sensitized by both TTDA and PTDA effectively, while the film sensitized by the mixture of PTDA and N3 dye has a maximum photo-electric conversion efficiency.

Key words: Oligo-thiophene carboxylic acid, Dye sensitization, Porous TiO₂ films, Photo-electric conversion