Reinforcing Oxygen Activation of Spinel Oxide via Mn─O Covalency Engineering for VOCs Oxidation

ABSTRACT Removing VOCs efficiently demands catalysts that activate oxygen at low temperatures. Here, Mn─O covalency in MnCo spinel is strategically modulated through an in situ hard‐templating method to incorporate Si and generate active oxygen species. Si incorporation induces Mn─O bond elongation and charge redistribution, weakening Mn─O covalency and forming Mn 4+ ─O─Co 3+ centers that promote dual activation of molecular and lattice oxygen. The optimized catalyst achieves T 90 of 168, 226, and 260°C for ethyl acetate, toluene, and propane, respectively, with excellent water resistance and long‐term stability (100 h) for ethyl acetate oxidation. Combined in situ spectroscopy (DRIFTS and EXAFS) studies and DFT calculations reveal that weakened Mn─O covalency can accelerate the rate‐limiting step of acetate oxidation to boost performance. This strategy can also be extended to synthesize MnO x , Co 3 O 4 , and MnCeO x for efficient VOC oxidation. Our work offers a new strategy to enhance oxygen activation via metal‐oxygen covalency modulation for low‐temperature VOC abatement.