Dual Regulation of Sensitizers and Cluster Catalysts in Metal–Organic Frameworks to Boost H2 Evolution

Photocatalytic efficiency is closely correlated to visible‐light absorption ability, electron transfer efficiency and catalytic center activity of photocatalysts, nevertheless, the concurrent management of these factors to improve photocatalytic efficiency remains underexplored. Herein, we proposed a sensitizer/catalyst dual regulation strategy on the polyoxometalate@Metal−Organic Framework (POM@MOF) molecular platform to construct highly efficient photocatalysts. Impressively, Ni‐Sb9@UiO‐Ir‐C6, obtained by coupling strong sensitizing [Ir(coumarin 6)2(bpy)]+ with Ni‐Sb9 POM with extremely exposed nickel site [NiO3(H2O)3], can drive H2 evolution with a turnover number of 326923, representing a record value among all the POM@MOF composite photocatalysts. This performance is over 34 times higher than that of the typical Ni4P2@UiO‐Ir constructed from [Ir(ppy)2(bpy)]+ and Ni4P2 POM. systematical investigations revealed that dual regulation of sensitizing and catalytic centers endowed Ni‐Sb9@UiO‐Ir‐C6 with strong visible‐light absorption, efficient inter‐component electron transfer and high catalytic activity to concurrently promote H2 evolution. This work opens up a new avenue to develop highly active POM@MOF photocatalysts by dual regulation of sensitizing/catalytic centers at the molecular level.