Effects of a TiO2:CaO barrier layer on the back electron transfer in TiO2-based solar cells

All the performance parameters of the DSSC with Ti:Ca(3:7)-TiO2/FTO electrode, which was prepared from a mixed solution with a molar ratio of 3:7 (TiCl4:CaCl2), were increased, compared to those of the reference device with a TiO2-only overlayer. This led to an about 17% enhancement in power conversion efficiency.