The research of CaO/TiO2 nanocrystalline film for dye-sensitized solar cell

Solar cell is the most effective form to use solar energy. The researchers focused on the dye-sensitized solar cell (DSSC) due to its low cost and high transformation efficiency. TiO₂ photoanode was modified by doping the wide band gap semiconductor of CaO into TiO₂ matrix. The influence of modification on DSSC was discussed in this paper. The results indicated that most CaO could pass into the surface structure of TiO₂ and the particle size of CaO was close to TiO₂. The forbidden band structure of TiO₂ was changed by the energy barrier of the CaO/TiO₂ core-shell film. The interface effect between CaO and TiO₂ could increase the transmission path of light inside the film and the absorbance was enhanced. Under the surface modification of CaO, the absorption capacity of N3 dye, absorbance and conversion efficiency were highly improved. Especially, the photoelectric conversion efficiency was increased 18.94% compared with pure TiO₂. Thus, we can improve the photoelectrical performance of DSSC by using surface modification.