Controlled Li Alloying by Post-Synthesis Electrochemical Treatment of Cu2ZnSn(S, Se)4 Absorbers for Solar Cells Universiteit Hasselt
Li-alloying of Cu2ZnSn(S, Se)4 (CZTSSe) absorbers is widely accepted for its beneficial influence on the performance of CZTSSe-based thin film solar cells. Given the degraded morphology characteristic of absorbers synthesized in the presence of excess Li concentrations, it is speculated that Li may be best incorporated into the absorber after synthesis. Here, we report an innovative method to add Li to synthesized CZTSSe by an electrochemical treatment using a liquid electrolyte. Our approach decouples Li addition from absorber synthesis, allowing one to possibly overcome morphology issues ...