Development of Economic Benzyl Alcohol-Based Polymers for Full Reaction Photocatalytic Hydrogen Peroxide Production

Porous organic polymers (POPs) have received extensive attention in photocatalytic hydrogen peroxide (H 2 O 2) production. Nonetheless, the main factors contributing to the arrival at practical application are the synthesis complexity, catalytic efficiency, operational stability, synthetic cost, and the long-overlooked water oxidation reaction (WOR). Herein, a series of metal-free photocatalysts were synthesized via a one-step Friedel–Crafts reaction using the inexpensive monomers 1, 4-benzenedimethanol and 4, 4′-bis (chloromethyl) -1, 1′-biphenyl, with a cost of 0. 084 g –1. Importantly, band structure engineering enables concurrent oxygen reduction reaction and WOR activation, achieving a record productivity of 3. 94 mmol g –1 h –1 under air. To facilitate economic scalability and reproducibility, a dual-liquid-phase cyclic system for continuous H 2 O 2 production was equipped to deliver H 2 O 2 in a controllable concentration, highlighting its practical application. This work advances the fundamental understanding of structure–activity correlations in heterogeneous photocatalysis while delivering an engineered solution for sustainable and cost-effective H 2 O 2 synthesis, bridging molecular-level design with scalable applications.