A single-site Cu( <scp>ii</scp> / <scp>i</scp> ) transition initiated by photo-doping for enhanced hydrogenation activity

Electronic metal-support interaction (EMSI) is prevalent yet critical for designing heterogeneous catalysts; unfortunately, this effect rapidly decays in regions away from the interface, and it is always coupled with structural changes, bringing great challenges when optimizing the catalytic performance. Here, a reversible Cu(II/I) transition in a single-site Cu catalyst initiated by photo-doping is proposed to regulate EMSI. It is found that electron-rich Cu sites at the interface can effectively stabilize the hydride intermediate, leading to an up to ∼20-fold increase in hydrogenation activity. Photo-induced interfacial doping will open versatile paths for designing heterogeneous catalysts for organic transformations.