Research progress of heterogeneous photocatalyst for H2O2 production: A mini review

H 2 O 2 is an excellent green oxidant with important applications in many fields. The conventional anthraquinone process for synthesizing H 2 O 2 is usually accompanied by high economic costs and stringent process requirements. The photocatalytic production of H 2 O 2 via heterojunction semiconductors has proven to overcome these limitations, which is a promising alternative to the conventional anthraquinone process. In this review, we provide a comprehensive summary of the semiconductor heterojunction materials that have been attempted to be used in the photocatalytic generation of H 2 O 2 in recent years. Firstly, a brief description of the photoreaction mechanisms of different types of heterojunctions in the photocatalytic process is presented, focusing on the generation pathways and competing reactions for the photoproduction of H 2 O 2 . Then, the types of heterojunctions applied for photoproduction of H 2 O 2 are comprehensively summarized. Among them, the four most widely used types of heterojunctions, including type-II heterojunctions, Z-scheme systems, S-scheme systems, and Schottky heterojunctions, and their current applications in the reaction of photoproduction of H 2 O 2 are highlighted. By comparing the differences in the internal electric fields of different types of heterojunctions, different charge transfer pathways of various types of heterojunctions in the photoproduction of H 2 O 2 are distinguished. Furthermore, the great potential of other types of heterojunctions, such as p-n heterojunctions, in photocatalysis is further outlined. Finally, the challenges as well as opportunities for the development of novel heterostructural photocatalysts for H 2 O 2 production are outlined. We sincerely hope this minireview can attract more attention from scientific research workers in the field of photocatalytic H 2 O 2 generation, making them valuable for environmental remediation and industrial applications in the future. Photocatalytic production of H 2 O 2 via heterojunction semiconductors has been shown to be a promising alternative to the conventional anthraquinone process. In this review, we provide a comprehensive summary of the semiconductor heterojunction materials and their advances for photocatalytic production of H 2 O 2 in recent years.