Perylene diimide-based photocatalysts: from molecular design to emerging applications

Perylene diimide (PDI)-based semiconductor materials show significant promise for photocatalytic environmental decontamination and the conversion of energy resources but suffer from inefficient photocarrier separation which greatly limits their activity. Consequently, designing PDI-based photocatalysts to enhance carrier separation has become a major research focus. This persistent challenge has positioned the rational design of PDI-based architectures to enhance carrier dissociation kinetics and elevate functional efficacy as a central focus point of research in the field of contemporary photocatalysis. This review firstly examines recent progress in the rational design of PDI-based photocatalysts and their charge transfer mechanism. Then, advances in the fabrication of PDI photocatalysts and associated electron/hole transfer mechanisms are discussed. It systematically evaluates their enhanced activity in key applications: water splitting, CO₂ reduction, N₂ fixation, and pollutant degradation etc. Subsequently, the fundamental photocatalytic mechanism inherent to PDI-based materials is scrutinized in depth. Finally, outstanding issues and prospective uses for PDI-based photocatalysts are also discussed. It is believed that this review provides a valuable direction for engineering advanced PDI-based photocatalytic systems.