Bi-Based Metal Halide Perovskites and Their Photocatalytic Properties: A Review

Semiconductor photocatalysis is a sustainable technology to address environmental pollution problems by efficiently utilizing solar energy. Developing efficient photocatalysts is particularly important. Recently, metal halide perovskites, especially lead halide perovskites (LHPs), have garnered widespread interest in photocatalytic fields due to their unique optoelectronic properties. However, the high toxicity of elemental lead has become a significant obstacle restricting the practical application of LHPs. In response, bismuth halide perovskites (BHPs) have emerged as a promising alternative. This review summarizes recent advances in this exciting area. First, we examine the wet-chemical synthesis methods for various BHPs. The physicochemical properties of BHPs are then discussed, with special emphasis on their stability. Methods to enhance stability, including composition engineering, surface engineering, and packaging engineering, are described. Emerging applications of BHPs in photocatalytic hydrogen production (H2), carbon dioxide (CO2) reduction, oxynitride (NOx) oxidation, organic synthesis and pollutant dye degradation are also reviewed. Finally, the challenges faced by BHPs and future research directions are analyzed and prospected.