Halide Perovskite Photocatalysts for Solar Energy Harvesting: Concept, Major Advances, and Challenges

Halide perovskite (HP) semiconductors have attracted considerable attention due to their easy preparation methods and unique optoelectronic properties such as high absorption coefficients, tunable bandgap engineering, and long charge-carrier diffusion lengths. While this class of materials has dominated the field of perovskite solar cells for the past two decades, there is now a shift toward other applications, particularly in solar energy harvesting and conversion as photocatalysts. This concept paper provides insights into the milestones of halide perovskite photocatalysts by highlighting their key properties that determine the catalytic functionality and performance. It briefly reviews the important physicochemical and structural properties of halide perovskites that influence their photocatalytic performances. Finally, it discusses the main challenges and strategies for enhancing their performance and durability.