The Enhanced Photovoltaic Performance of Sb 2 S 3 Solar Cells by Thermal Decomposition of Antimony Ethyl Xanthate with Thiourea Doping

The thermal decomposition method is regarded as a simple and effective way to prepare Sb 2 S 3 films. Herein, Sb 2 S 3 films are prepared by thermal decompositions of antimony ethyl xanthate (Sb(xt) 3 ). During the thermal decompositions process, sulfur vacancy defects are easily formed because of high temperatures. To reduce the sulfur vacancy defects in the final Sb 2 S 3 films, thiourea (TU) is introduced in the Sb(xt) precursor. By doping with TU, the crystallinity of the Sb 2 S 3 films improves and dense Sb 2 S 3 films are formed. With the decrease in sulfur defects, the carrier concentrations are greatly increased from 2.5 × 10 16 to 6.2 × 10 16  cm −3 . Compared with the no‐doping Sb 2 S 3 solar cells, the power conversion efficiency of Sb 2 S 3 solar cells with doping 25% TU is improved from 2.85% to 3.70%.