Single-source thermal evaporation converts anion controllable Sb2(S,Se)3 film for fabricating high-efficiency solar cell

Antimony selenosulfide (Sb-2(S,Se)(3)) is a promising photovoltaic material because of its high chemical stability, optimal optoelectronic properties, and low-cost advantages. However, finding suitable material processing approaches to obtain elemental controlled Sb-2(S,Se)(3) films with suppressed deep-level defects poses fundamental demands and challenges to developing this emerging solar technology. Here, we developed a robust method for tailoring the composition of the film through controlling the anion elements. The films were prepared by evaporating the presintered Sb-2(S,Se)(3) alloy compound via a single-source thermal evaporation process. A quasi-precise estimate of single-phase Sb-2(S,Se)(3) films was made by sintering Sb, S, and Se elemental precursors and adjusting the anion molar ratio in the prefabricated Sb-2(S,Se)(3) alloy compound, and the elemental ratio of the precursor alloy compound was maintained in the as-obtained Sb-2(S,Se)(3) films. A highly efficient Sb-2(S,Se)(3) solar cell with a power conversion efficiency of 8.25% was achieved by introducing low-cost CuPc-doped P3HT as a hole-transporting layer. Here, we demonstrate the dependence of deep-level defects and oriented crystal growth on the S/Se atomic ratios and show how tunability can be used to improve carrier transport for photovoltaic energy conversion. Our study presents a novel approach to fabricating metal chalcogenide semiconducting films and improving the performance of Sb-2(S,Se)(3) solar cells.