Al2O3-coated SnO2/TiO2 composite electrode for the dye-sensitized solar cell

A novel Al2O3-coated SnO2/TiO2 composite electrode has been applied to the dye-sensitized solar cell. In such an electrode, two kinds of energy barriers (SnO2/TiO2 and TiO2/Al2O3) were designed to suppress the recombination processes of the photo-generated electrons and holes. After the SnO2 was modified by colloid TiO2, the photoelectric conversion efficiency of the SnO2/TiO2 composite cell increased to 2.08% by a factor of 2.8 comparing with that of the SnO2 cell. The Al2O3 layer on the SnO2/TiO2 composite electrode further suppressed the generation of the dark current, resulting in 37% improvement in device performance comparing with the SnO2/TiO2 cell.