TiO2 inverse opal based CdS/CdSe quantum dot co-sensitized solar cells

CdS and CdSe quantum dots were introduced as co-sensitizers into TiO2 inverse opal quantum dot sensitized solar cells. Herein, the three-dimensionally ordered porous TiO2 inverse opal film leads to a better infiltration of both sensitizers and hole transporting material, and the smaller surface area of TiO2 inverse opal film is effectively offset by the incorporating of co-sensitization. It was found that the presence of CdS/CdSe co-sensitizers provides enhanced light absorption, and leads to a lower recombination rate of the electrons due to the stepwise structure of band edge in TiO2/CdS/CdSe, which resulted in the observed enhanced photocurrent and energy conversion efficiency of the solar cells. A cell efficiency of 1.01 % has been attained.