Sb2Se3 solar cells fabricated via close-space sublimation

Abstract

Antimony selenide (Sb2Se3) is regarded as an excellent photovoltaic absorber material due to its suitable bandgap, large light absorption coefficient, abundant raw material reserves, and environmental friendliness. However, the commonly used rapid thermal evaporation strategy for deposition of Sb2Se3 films results in low film quality, which is undesirable from the perspective of photovoltaic performance. Herein, we fabricate highly efficient and stable Sb2Se3 solar cells via a close-space sublimation (CSS) process, which allows separate control of the source and substrate temperatures, leading to high-quality thin films and better solar cell performance. Four growth patterns of Sb2Se3 thin films are optimized by controlling the source temperature of CSS. It is found that the Sb2Se3 thin film prepared at 475 °C has the best crystallinity, smoothest surface, and best density. Moreover, solar cells based on ZnO/Sb2Se3 thin films can achieve maximum efficiency with VOC of 0.312 V, JSC of 27.91 mA/cm2, fill fact of 41.35%, and power conversion efficiency of 3.61%. The performance of the devices was not adversely affected by the air environment, and thus, they were shown to exhibit appropriate stability.