Heterointerface of\nMonodispersed Ultrathin-MnO<sub>2</sub>@Amorphous Carbon to Attain\nDurable Lattice Oxygen Redox Chemistry\nthrough Creation of Dual Lattice Oxygens

Lattice oxygen (O<sub>L</sub>) redox chemistry is a key\nto alleviating\nthe energy and environmental crisis, but it faces challenges in activating\nthe O<sub>L</sub> while ensuring structural stability. We disclosed\nherein that engineering a heterogeneous interface between ultrathin\noxide and amorphous carbon can attain the durable O<sub>L</sub> redox\nchemistry without introducing catalytically impure sites. To this\nend, we proposed a green strategy to grow ∼3.9 nm-thickness\nwrinkled δ-MnO<sub>2</sub> nanosheets that are rich in defects\nand are vertically aligned on amorphous carbon spheres. Experiments\nand calculations reveal that the electrons can easily migrate from\nthe amorphous carbon to MnO<sub>2</sub> at the δ-MnO<sub>2</sub>@C heterointerface. The heterogeneous interfaces can not only regulate\nthe Mn–O bond and create oxygen defects in δ-MnO<sub>2</sub> but also introduce lattice oxygen with varying reactivities.\nSpecifically, the δ-MnO<sub>2</sub>@C structure carries more\nactivated lattice oxygen that contributes to the enhanced activity\non catalytic oxidation of bioderived 5-hydroxymethylfurfural (HMF)\nto 2,5-furandicarboxylic acid (FDCA), with a high FDCA formation rate\nof 1759 μmol gcat<sup>–1</sup> h<sup>–1</sup> and\na high selectivity of 95%. The heterogeneous interface of MnO<sub>2</sub>@C also brings inert lattice oxygen, so that it manifests\nhigh structural stability during the oxidation reactions. This work\ndeepens the fundamental understandings in the engineering of lattice\noxygen for durable lattice oxygen redox chemistry and showcases an\neffective interface technique in creating advanced catalysts for clean\nsustainable energy.