Thin film AgBiS2 solar cells with over 10 % power conversion efficiency enabled by vapor-assisted solution process treatment

Abstract

Recently, thin film photovoltaic solar energy has grown rapidly with new materials for achieving high conversion efficiency and long-term stability. Especially, silver bismuth sulfide (AgBiS) nanocrystal-based quantum-dots have emerged as viable absorber for cost-effective photovoltaic. However, a thick AgBiS quantum-dots layer always faces the dilemma of entailing the charge carrier collection and trap-assisted recombination. Here we show a vapor-assisted solution process to fabricate high crystallinity submicron-grain AgBiS films. The resultant devices with small active area (0.06 cm) achieved a record-breaking power conversion efficiency of 10.20 % and large active area (1.00 cm) achieved an efficiency of 9.53 % under 100 mW cm standard AM 1.5 global sunlight simulation, both of which are the highest reported for thin film AgBiS solar cells to date. Notably, the solar cells based on submicron-grain AgBiS thin films showed an exceptional durability, maintaining over 94 % of the initial PCE for 3000 h in ambient air, along with excellent stability under extreme conditions, including exposure to 85 °C and 85 % relative humidity.