Performance improvement of nanocrystalline Cu2O-based counter electrons for dye-sensitized solar cells by Sn alloying

Cu2O is considered as a good potential alternative material of Pt as the counter electrode in dye-sensitized solar cell. While for Cu2O-based dye-sensitized solar cells (DSSCs), the counter electrode is unstable, and the photoelectric conversion efficiency (PCE) is still very unsatisfactory. In this work, we tried alloy Sn to Cu2O for improvement. It turns out that Sn-alloyed Cu2O can produced uniform nanoholes in the counter electrode film, which can increase the specific surface area of electron transport. The process annealing can play important role for decrease the band gap of the film. The reaction time of Sn alloying has a key influence on the PCE of Sn-alloyed Cu2O-based DSSCs. Generally, more reaction time makes better PCE, of which in our experiments, the 8 h one has the best PCE than others, which has improved more than 5 times of the pure Cu2O one.

Automated summary

In this study, Sn-alloyed Cu2O was used as a potential alternative material for the counter electrode in dye-sensitized solar cells. It was found that Sn-alloyed Cu2O can increase the specific surface area of electron transport and decrease the band gap of the film through the annealing process. The reaction time of Sn alloying has a significant influence on the photoelectric conversion efficiency of the cells.