Selenization of Sb2Se3 absorber layer: An efficient step to improve device performance of CdS/Sb2Se3 solar cells

Sb2Se3 appeared as a very promising solar absorber because of their attractive material, optical and electrical properties. Previously, we reported thermal evaporated superstrate CdS/Sb2Se3 solar cell achieving 1.9% efficiency. In this letter, we improved device performance to 3.7% (Voc = 0.335 V, Jsc = 24.4 mA/cm2, and FF = 46.8%) by an additional selenization step. Careful external quantum efficiency, capacitance-voltage profiling, and photoresponse study indicated selenization probably compensated selenium loss during thermal evaporation, reducing VSe associated recombination loss and improving device performance.