Development strategies and improved photocatalytic CO2 reduction performance of metal halide perovskite nanocrystals

In recent years, photocatalytic CO2 reduction reaction (CRR) has attracted much scientific attention to overcome energy and environmental issues by converting CO2 into high-value-added chemicals utilizing solar energy. Metal halide perovskite (MHP) nanocrystals (NCs) are recognized as an ideal choice for CRR owing to their outstanding optoelectronic properties. Although great efforts have been devoted to designing more effective photocatalysts to optimize CRR performance, severe charge recombination, instability, and unsatisfactory activity have become major bottlenecks in developing perovskite-based photocatalysts. In this review, we mainly focus on the recent research progress in the areas of relevance. First, a brief insight into reaction mechanisms for CRR and structural features of MHPs are introduced. Second, efficient modification approaches for the improvement of the photocatalytic activity and stability of the perovskite-based catalysts are comprehensively reviewed. Third, the state-of-the-art achievements of perovskite-based photocatalysts for CRR are systematically summarized and discussed, which are focused on the modification approaches, structure design, and the mechanism of the CO2 reduction process. Lastly, the current challenges and future research perspectives in the design and application of perovskite materials are highlighted from our point of view to provide helpful insights for seeking breakthroughs in the field of CRR. This review may provide a guide for scientists interested in applying perovskite-based catalysts for solar-to-chemical energy conversion.