Enhancing the efficiency of Sb2S3 solar cells using dual-functional potassium doping

Antimony sulphide (Sb 2 S 3 ) thin films have attracted considerable research interest as a photovoltaic absorber material owing to their suitable band gap, large absorption coefficient, and excellent photoelectronic properties. In this study, cadmium sulphide (CdS) films were doped with potassium , which increased their crystallinity and optical transmission . These films were then used as a buffer layer to increase the efficiency of Sb 2 S 3 solar cells. Furthermore, the potassium diffused into the Sb 2 S 3 film, which increased their crystallinity and light absorption and decreased its surface roughness. Dual-functional potassium doping helped improve all of the photoelectric parameters of the Sb 2 S 3 solar cells. Specifically, the device efficiency increased from 4.57% to 6.53% (an increase of 42.89%), and a high current density of 15.29 mA cm −2 was achieved. These findings are expected to facilitate the further development of Sb 2 S 3 thin-film solar cells for industrial applications.