Dye-Sensitized Solar Cells based on SnO2-doped TiO2 photoelectrodes

Abstract

Dye-sensitized solar cells (DSSCs) based on nanocrystalline TiO2 photoelectrodes have attracted considerable interest as potential candidates to replace conventional Si-based solar cells in specialized applications because of low manufacturing cost and easy fabrication. Conversion efficiency has been achieved as high as 11% but is still insufficient for commercialization. One effective method to improve the efficiency is to suppress recombination steps; some electrons in the conduction band of TiO2 travel back to either electrolyte or oxidized dye. In principle, the formation of cascading band structure by adding the other semiconductor material in the TiO2 photoelectrode could help the charge transport and suppress the recombination steps. In this study, TiO2 nanoparticles mixed with SnO2 nanoparticles, which forms the cascading band structure with TiO2, was prepared through hydrothermal process and applied to the photoelectrodes of DSSCs. The influence of the SnO2 amount on the performances of the fabricated cells was investigated and discussed.