Covalent Heterojunction Enhances Electron Transfer and Oxygen Activation for Photocatalytic C(sp3)−C(sp2) Cross-Dehydrogenative Coupling Reaction

Abstract

Heterogeneous aerobic photocatalytic oxidation has emerged as a powerful strategy for efficiently organic transformations, thus making O2 activation extremely attractive but challenging due to the spin-prohibited nature of O2. Herein, we construct covalently bonding Type-II heterojunction by integrating PCN-222(Cu) and the triazine framework (TR-1). Specifically, the strong covalent bond between the two components can extend visible-light absorption range and facilitate robust interfacial electron transfer, enabling faster separation of photo-induced charge carriers. Consequently, it can effectively activate O2 through enhanced electron transfer, exhibiting greater catalytic performance with high yields (90%) than the parent compound and those samples without covalent linkage between two components, extensive adaptability for various substrates, and excellent recyclability in the photocatalytic aerobic oxidative C(sp 3 )-C(sp 2 ) crossdehydrogenative coupling reaction. We believe that this is a powerful approach for boosting photocatalytic O₂ activation and offers new insights into manufacturing more composite materials for organic transformations.