Structural design and property regulation of organic polymers for photocatalytic synthesis of H2O2

Abstract

Hydrogen peroxide (H₂O₂), an environmentally benign oxidizer, finds extensive applications in pulp bleaching, wastewater treatment, and medical sterilization. Photocatalytic H₂O₂ synthesis via water and oxygen activation on semiconductor surfaces presents a sustainable production strategy. Notably, structurally tunable organic photocatalysts have emerged as promising candidates, in which targeted molecular engineering can boost the photocatalytic performance by enlarging specific surface areas, extending light absorption ranges, and facilitating charge carrier transport-separation dynamics. Given the growing significance of organic photocatalysts in H₂O₂ synthesis, a comprehensive review of this field has become imperative. This paper offers a systematic examination of visible-light-driven H₂O₂ synthesis using various organic photocatalysts, including graphitic carbon nitride (g-C₃N₄), resorcinol-formaldehyde (RF) resin, covalent organic frameworks (COFs), and linear conjugated polymers (LCPs). The focus lies on fundamental mechanistic elucidation, design of reaction pathways and active sites, modification strategies, and establishment of efficient photocatalytic systems. Extensive studies have correlated photocatalytic efficiency with interfacial electron transfer kinetics and spatial charge separation. Therefore, we methodically analyze key determinants governing photogenerated carrier dynamics and present engineering strategies for performance enhancement. Furthermore, we discuss emerging application scenarios enabled by photocatalytic H₂O₂ generation. Importantly, this review critically evaluates persistent challenges and cutting-edge solutions in visible-light-mediated H₂O₂ synthesis, ultimately providing design principles for developing high-efficiency organic photocatalysts.