Low-Cost Fabrication of Sb2S3 Solar Cells: Direct Evaporation from Raw Stibnite Ore

Antimony sulfide is an emerging 1D nontoxic Earth-abundant photovoltaic material with favorable wide bandgap as a suitable top-cell candidate for multijunction tandem solar cells. However, the current fabrication technology for Sb 2 S 3 solar cells relies heavily on a high-purity Sb 2 S 3 source, which limits its large-scale deployment. Therefore, it is attractive to fabricate the Sb 2 S 3 solar cells directly from the raw stibnite source, which can be cost effective by avoiding the complicated, costly purification and refinement process of the stibnite ore, while reducing process-emitted pollution. Herein, high-quality Sb 2 S 3 films (thickness: ≈1 μm) by the vapor transport deposition of raw stibnite ore powder are obtained, followed by a sulfurization process to remove the surface oxides and facilitate alkali element redistribution. In this way, the particle size is increased from ≈500 nm to ≈1.5 μm, the carrier concentration of the Sb 2 S 3 film is increased from ≈10 15 to ≈10 16 cm −3 , and the power conversion efficiency of Sb 2 S 3 solar cell is increased by more than two times. Through the elemental distribution analysis, it is found that it is the redistribution of alkali elements introduced from the natural stibnite ore that induces the grain growth, contributes toward defect suppression, and leads toward enhanced device performance.