Advancing Lead-Free Cs2AgBiBr6 perovskite solar cells: Challenges and strategies

Halide perovskite solar cells (PSCs) have become a representative of novel photovoltaic power generation technologies. However, the toxicity and instability problems of lead (Pb) halide perovskite constitute a major obstacle to their commercialization. In recent years, a nontoxic, highly stable lead-free double perovskite Cs2AgBiBr6 cells emerged as a promising alternative to Pb-based PSCs, which is quickly becoming one of the hottest topics in photovoltaics. This review identifies the major challenges faced by Cs2AgBiBr6 PSCs and provides a comprehensive review on corresponding solution strategies for the community. These results will contribute insights and theoretical guidance to the subsequent development of Cs2AgBiBr6 PSCs. Finally, we propose research perspectives toward efficient, eco-friendly, and practical photovoltaic Cs2AgBiBr6 PSCs.