Doping Strategies in Sb2S3 Thin Films for Solar Cells

Sb2S3 is an attractive solar absorber material that has garnered tremendous interest because of its fascinating properties for solar cells including suitable band gap, high absorption coefficient, earth abundance, and excellent stability. Over the past several years, intensive efforts have been made to enhance the photovoltaic efficiencies of Sb2S3 solar cells using many promising approaches including interfacial engineering, surface passivation, additive engineering, and band-gap engineering of the charge transport layers and active light absorbing Sb2S3 materials. Recently, doping strategies in Sb2S3 light absorbers have gained attention as they promise to play important roles in controlling band gap, regulating film morphology, and passivating grain boundaries, and thus resulting in enhanced carrier transport, which is one of the most challenging issues in this cutting-edge research field. In this review, after a brief introduction to Sb2S3, an overview of Sb2S3 solar cells and their fundamental properties are provided. Recent advances in doping strategies in Sb2S3 thin films and solar cells are then discussed to provide in-depth understanding of the effects of various dopants on the photovoltaic properties of Sb2S3 materials. In conclusion, the personal perspectives and outlook to the future development of Sb2S3 solar cells are provided.