Optimizing lead-free halide perovskites: Strategies for enhanced performance and selectivity in photocatalytic CO2 reduction

Solar energy-powered photocatalytic processes represent a promising avenue for sustainable energy and chemical production. Among these, lead-free halide perovskites (LFHPs) have garnered attention as a next-generation class of photocatalysts for CO₂ reduction, offering the advantages of high light absorption and low toxicity. However, the practical application of LFHPs remains constrained by limited catalytic activity and poor product selectivity. This review discusses the advancements in strategies to enhance the catalytic efficiency of LFHPs, such as compositional engineering, surface passivation, and heterostructure formation. These approaches aim to optimize charge carrier dynamics, reduce recombination rates, and improve stability under reaction conditions. Emphasis is also placed on methods to control product selectivity, including tailored reaction environments, co-catalyst integration, and fine-tuning electronic band structures. The discussion extends to key challenges such as material stability under photocatalytic conditions, scalability for industrial applications, and a deeper understanding of reaction mechanisms at the molecular level. Finally, future prospects highlight the critical role of LFHPs in achieving efficient, scalable, and eco-friendly solar-driven chemical synthesis, highlighting their potential to reshape the landscape of sustainable photocatalysis.