Metal halide perovskites for photocatalytic CO2 reduction: An overview and prospects

Recent advances and perspectives of MHPs are summarized for improving the photocatalysis of CO2 reduction. [Display omitted] •Introduction of the research progress mechanism of photocatalytic CO2 reduction.•The physicochemical properties, synthesis methods and applications of MHPs for photocatalytic CO2 reduction have been summarized.•Key strategies to improve performance of MHPs for photocatalytic CO2 conversion.•Main challenges and prospects of MHPs for photocatalytic CO2 reduction have been discussed. As the increasing consumption of fossil fuels, the CO2 emission rapidly increased, which has severely caused energy crisis and climate problems. Directly converting CO2 to high added value chemical fuels via solar energy harvesting offers a route to alleviate these problems. To realize this goal, a photocatalyst of low cost, high efficiency and practical durability is urgently needed. Metal halide perovskites (MHPs) have been used as important materials for application in photovoltaics field, which also have been considered ideal materials for photocatalytic CO2 reduction recently, since the first report in 2017. This review focuses on the physicochemical properties, synthesis methods, the overview advances of different strategies for MHPs promoting the performance of photocatalytic CO2 conversion to solar fuels, including size and facets effects, ion doping or exchange, anchored cocatalysts, semiconductor heterojunctions and Pb-free MHPs. Based on these advances, the main challenges of stability and toxicity, photocatalytic activity and selectivity, prospects of theoretical calculations, and solar cell device and derived catalytic applications of MHPs are also proposed. This review sheds light on the construction of efficient MHPs toward industrialization applications for CO2 reduction in future.