Effective Non-Radiative Interfacial Recombination Suppression Scenario Using Air Annealing for Antimony Triselenide Thin-Film Solar Cells

Abstract

Antimony triselenide (Sb2Se3) has become a very promising candidate for next-generation thin-film solar cells due to the merits of their low-cost, low-toxic and excellent optoelectronic properties. Despite Sb2Se3 thin-film photovoltaic technology having undergone rapid development over the past few years, insufficient doping concentration and severe recombination have been the most challenging limitations hindering further breakthroughs for the Sb2Se3 solar cells. Post-annealing treatment of the Sb2Se3/CdS heterojunction was demonstrated to be very helpful in improving the device performance previously. In this work, post-annealing treatments were applied to the Sb2Se3/CdS heterojunction under a vacuum and in the air, respectively. It was found that compared to the vacuum annealing scenario, the air-annealed device presented notable enhancements in open-circuit voltage. Ultimately a competitive power conversion efficiency of 7.62% was achieved for the champion device via air annealing. Key photovoltaic parameters of the Sb2Se3 solar cells were measured and the effects of post-annealing treatments using different scenarios on the devices were discussed.