Research Progress of Construction and Photocatalytic Applications of Black Photocatalysts

Most traditional wide‐bandgap semiconductor photocatalysts only respond to ultraviolet light, leading to extremely low solar energy utilization and severely hindering practical applications. Blackening modification has emerged as a robust strategy to overcome this limitation, as it enables photocatalysts to extend light absorption into visible and near‐infrared regions, remarkably improving both light absorption efficiency and catalytic potential. This review systematically summarizes recent advances in black photocatalysts. It first elaborates on the intrinsic enhancement mechanisms behind blackening behavior, including defect introduction and bandgap narrowing. Subsequently, it categorizes mainstream black photocatalytic systems, including black TiO 2 , black phosphorus (BP), black graphitic carbon nitride (black g‐C 3 N 4 ), and various black material‐based composite heterojunctions, while comprehensively analyzing their structural configurations and optical properties and summarizing multiple feasible preparation strategies. Furthermore, this work demonstrates broad application prospects in diverse fields, covering photocatalytic water splitting for hydrogen production, carbon dioxide photoreduction, organic pollutant mineralization and degradation, as well as photocatalytic nitrogen fixation. Finally, the review concludes the major challenges currently constraining further development, including stability and scalability issues. Based on these, future research priorities and optimized application directions for high‐efficiency black photocatalysts are prospected, aiming to provide valuable theoretical guidance for the subsequent design of advanced photothermal‐coupled photocatalytic materials.