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

• Published in: Solar energy materials and solar cells 2021-03, Vol.221, p.110816, Article 110816
• Main Authors: Ning, Huan, Guo, Huafei, Zhang, Jiayi, Wang, Xin, Jia, Xuguang, Qiu, Jianhua, Yuan, Ningyi, Ding, Jianning
• Format: Article
• Language: English
• Subjects: Absorption; Absorptivity; Antimony; Buffer layers; Cadmium; Cadmium sulfide; Carrier recombination; Crystal structure; Crystallinity; Doping; Dual function; Efficiency; Electromagnetic absorption; Industrial applications; Photoelectricity; Photovoltaic cells; Photovoltaics; Potassium; Potassium doping; Sb2S3; Solar cells; Sulfides; Surface roughness; Thin films
• ISSN: 0927-0248; 1879-3398
• DOI: 10.1016/j.solmat.2020.110816

Antimony sulphide (Sb2S3) 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 Sb2S3 solar cells. Furthermore, the potassium diffused into the Sb2S3 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 Sb2S3 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 Sb2S3 thin-film solar cells for industrial applications. •Potassium doped CdS films were used as a buffer layer to increase the efficiency of Sb2S3 solar cells. The potassium diffused into the Sb2S3 film, increased their crystallinity and light absorption and decreased its surface roughness.•Dual-functional potassium doping helped improve all of the photoelectric parameters of the Sb2S3 solar cells.•Potassium doping can significantly reduce the carrier recombination in Sb2S3 solar cells.•The device efficiency increased from 4.57% to 6.53% (an increase of 42.89%), and the cells delivered a high current density of 15.29 mA.cm-2 was achieved.•Cadmium sulphide (CdS) films were doped with potassium, which increased their crystallinity and optical transmission.•Doping enhance the separation of photoelectron and hole pairs, the interfacial charge transfer ability improved.