Lead‐Free Halide Perovskite Photocatalysts for Photocatalytic CO2 Reduction: A Review

Solar‐driven CO 2 conversion is a promising strategy for solving energy and environmental crises. Developing photocatalysts with high performance is the key to achieve efficient CO 2 conversion. Lead halide perovskite is considered as a promising photocatalyst for solar‐driven CO 2 conversion due to its excellent properties. However, the toxicity of Pb significantly limits their practical applications. Therefore, developing the lead‐free perovskite photocatalysts has full scientific significance in greatly expanding their application scenarios and reducing the risk of environmental damage. At present, the lead‐free perovskite photocatalysts are attracting widespread attention from researchers and is currently a research hotspot in the field of photocatalysis. Herein, this review systematically describes the crystal structure, photochemical characteristics, preparation methods, and photocatalytic properties. Then, based on the mechanisms of photocatalytic CO 2 reduction, this review explores the structure–activity relationship between the microstructure of perovskite and its photocatalytic performance in detail and introduces the modification strategies of lead‐free halide perovskite. Finally, the development prospects and challenges of lead‐free halide perovskite photocatalysts are discussed to fully explore their inherent potential for efficient photocatalytic CO 2 reduction. This work provides insights and reference significance for further development of lead‐free halide perovskite photocatalysts for photocatalytic CO 2 reduction.