Electronic Structure Tailoring of COFs Photocatalysts via Triazine Moieties for Efficient H2O2 Generation and Water Decontamination
Developing efficient photocatalysts for hydrogen peroxide (H2O2) synthesis is vital for sustainable chemistry, yet optimizing the electronic structure of triazine-based covalent organic frameworks (COFs) through precise spatial engineering remains a challenge. In this work, we constructed four model COFs to systematically decode how the spatial arrangement and incorporation level of triazine moieties regulate the electronic structures and H2O2 production efficiency. Combined experimental and theoretical analyses revealed that FB-AT achieved an optimal donor-acceptor architecture via rational spatial arrangement of triazine and benzene moieties. This configuration established an intramolecular potential gradient, which not only promoted charge separation by suppressing the exciton binding energy but also enriched the electron density at triazine sites. These electron-rich active centers significantly facilitated the oxygen reduction reaction by lowering the thermodynamic energy barrier for *OOH intermediate formation. Consequently, FB-AT exhibited a remarkable H2O2 production rate of 11055 μmol g-1 h-1 in pure water, along with a superior solar-to-chemical conversion efficiency of 1.16%. Additionally, FB-AT enabled complete degradation of phenol, tetracycline, and rhodamine B within 5–15 min of visible light irradiation. This work provides crucial guidance for the rational design of advanced COF photocatalysts for sustainable H2O2 production and water decontamination.