Boosting Photocatalytic H ₂ O ₂ Production via the Synergy of Protonation and Heterojunction in Covalent Organic Frameworks

With high specific surface area, tunable framework structures, and outstanding chemical stability, covalent organic frameworks (COFs) can serve as photocatalysts to convert water into H₂O₂ under light irradiation. However, their low electronic transfer rates and narrow optical response range significantly constrain the application of COFs in photocatalysis research. Herein, a compound with an S-scheme heterojunction structure was synthesized by combining Dma-TAPT COFs with polyaniline (PANI) via a solvothermal method. Furthermore, protonated COFs were used to broaden the light absorption range and enhance charge transport. Owing to the synergistic effect, the photocatalytic H₂O₂ production of PANI-Dma-TAPT after protonation increased by 2.58 times (relative to Dma-TAPT). Under acidic conditions (pH 1), the H₂O₂ yield of H-PANI-Dma-TAPT reached 1171.7 μmol·g^-1, which was 3.7 times higher than that of Dma-TAPT. This study offers both practical insights and theoretical understanding into photocatalytic H₂O₂ production.