Polymer semiconductors: A unique platform for photocatalytic hydrogen peroxide production

Hydrogen peroxide (H2O2) has attracted considerable attention as an environmentally friendly oxidant and a potential energy carrier. In comparison to the traditional anthraquinone method, photocatalytic H2O2 synthesis from molecular oxygen and water offers an appealing route for sustainable and costeffective H2O2 synthesis. Recently, polymer semiconductors have emerged as a promising class of metal-free photocatalysts for H2O2 production owing to their abundant building blocks and versatile synthetic methods. These distinctive features allow for the rational molecular design of organic semiconductors and the modulation of their photophysical and photocatalytic properties, making them ideal candidates for high-efficiency photocatalysis. Herein, we summarize the latest advances in the development of polymer semiconductors for photocatalytic H2O2 production. This review starts with a brief introduction of the fundamental principles and reaction systems involved in photocatalytic H2O2 production. Subsequently, the molecular design strategies of polymer photocatalysts are discussed in detail for enhancing charge separation and promoting surface catalytic reactions. At last, the existing challenges and possible opportunities in this field are presented. This review aims to provide detailed insights and guidelines for the rational design of innovative organic semiconductors for efficient photocatalytic H2O2 production.