Rational Construction of Donor–Acceptor Covalent Organic Framework Heterojunction for High-Performance Photocatalytic Production of H 2 O 2

H 2 O 2 production via dual channels based on both the oxygen reduction reaction (ORR) and water oxidation reaction (WOR) remains significantly challenging while meaningful. Here, we rationally constructed electron donor–acceptor COFs@COFs, i.e., D@A-COF, by in situ growth of electron-acceptor COF (A-COF) on electron-donor COF (D-COF) for efficient H 2 O 2 production according to the synergetic donor–acceptor (D–A) and heterojunction strategies. A specific S-scheme of heterojunction was formed favorably at the boundary, and the stable C═N covalent bonds connected D-COF and A-COF, and hence as-prepared D@A-COF exhibited a wider light range, stronger absorption, and faster electron–hole separation and transfer ability than the primitive COFs. Impressively, the photocatalytic H 2 O 2 production rate of D@A-COF was up to 5462 μmol h –1 g –1, significantly higher than the counterpart D-COF (325 μmol h –1 g –1 ), A-COF (1860 μmol h –1 g –1 ), D-A-COF-1 (657 μmol h –1 g –1 ), and D-A-COF-2 (201 μmol h –1 g –1 ). The results showed that the overall photocatalytic production of H 2 O 2 by D@A-COF was carried out simultaneously through dual channels of the ORR and WOR, and the ORR likely occurred in D-COF, while the WOR was mostly located in A-COF. This work highlights the rational construction of donor–acceptor COFs@COFs heterojunction, providing unique insight into efficient photocatalysts for H 2 O 2 production.