Enhancement of the Photoelectric Performance of Dye-sensitized Solar Cells by Sol-gel Modified TiO2 Films

Modified TiO2 films have been prepared by combining commercial titania powders (Degussa P25) with sol-gel made by titanium chloride (Ti-sol). The result shows that clusters are formed by nanoparticles and large pores can be seen on the surface of the TiO2 films. The short circuit photocurrent density and photoelectric conversion efficiency of the solar cells are obviously enhanced compared with those without modification. The relationship between the photoelectric conversion efficiency and the amount of Ti-sol was investigated. With the addition of 30 wt% Ti-sol, the photoelectric conversion efficiency as high as 9.75% is achieved, increasing by 28.3% compared with the solar cells without modification.