Synergistic Cu ₂ and Polyoxometalate Clusters in Metal–Organic Layers Enable Oxidant‐Free CH ₄ Photooxidation

Abstract Methane (CH 4 ) photooxidation under mild conditions represents a transformative approach for sustainable production of fuel and chemicals, however, it remains challenging due to the persistent requirement for exogenous oxidants. Herein, this study reports a series of well‐defined bicluster photocatalysts Cu 2 POF Mn /PCN‐n (n = 1/5/8/10, denoting the mass ratio of PCN: Cu 2 POF Mn ), constructed by integrating [Cu(µ 2 ‐I)] 2 (denoted as Cu 2 ) clusters and MnMo 6 polyoxometalates (POMs) within ultrathin metal–organic layers (MOLs) anchored on PCN nanoflakes. The optimized Cu 2 POF Mn /PCN‐8 photocatalyst achieves efficient CH 4 conversion to HCOOH with 10.5 mmol g POF −1 yield and 95% selectivity without any exogenous oxidant. Comprehensive studies demonstrated that the engineered MOLs architecture enables uniform and ordered assembly of complementary catalytic bicluster, where MnMo 6 POMs act as electron reservoirs to promote charge separation for in situ H 2 O 2 generation, and Cu 2 clusters mimic CH 4 monooxygenase to selectively cleave C−H bonds via forming Cu 2 −O···H···CH 3 intermediate. This work highlights the vital role of MOL‐directed bicluster assembly for C–H functionalization that bypasses the need for sacrificial oxidants in selective CH 4 functionalization.