Photoredox catalysis over semiconductors for light-driven hydrogen peroxide production

Hydrogen peroxide (H₂O₂) is a commodity chemical applied in diverse products and industries. Nevertheless, its current industrial production process is not sustainable. Photoredox catalysis over semiconductors is a very promising and green process that can harness solar energy for the sustainable production of H₂O₂from just water (H₂O) and oxygen (O₂). From the viewpoint of photochemical reactions, this review presents the latest advances in light-driven H₂O₂production by three kinds of semiconductor materials,i.e., homogeneous photocatalysts, heterogeneous photocatalysts, and photoelectrochemical catalysts. Starting with a brief introduction to photocatalysis, it then presents the main pathways (oxygen reduction, water oxidation, and integrated dual-channel pathway) involved in light-driven H₂O₂generation. The latest photocatalysts for H₂O₂production are elucidated thereafter. Finally, an outlook on the most urgent challenges and corresponding unexplored research opportunities of light-driven H₂O₂production by semiconductors is provided. This review aims to provide in-depth insights and guidelines to stimulate the development of innovative semiconductor materials for sustainable H₂O₂productionviaphotoredox catalysis reactions.