Revealing the Jahn–Teller\nMitigating Complexity\nof Se-Anchored Mn Oxides for Superior SO<sub>2</sub> Resistance in\nGaseous Molecular Oxygen Activation

Manganese oxides have emerged as promising catalysts\nfor the low-temperature\nactivation of molecular oxygen (O<sub>2</sub>), crucial for the catalytic\noxidation and removal of gaseous pollutants. However, the undesired\nJahn–Teller (J-T) effects associated with the Mn<sup>iv</sup>/Mn<sup>iii</sup> redox couple, particularly under SO<sub>2</sub> poisoning, led to the effectiveness of Mn oxides in applications.\nHerein, we construct a highly covalent Se<sup>iv</sup>-O-Mn<sup>iii</sup> structure via the introduction of selenium into α-MnO<sub>2</sub>. Such a structure features high-valence Se<sup>iv</sup> anchored\non the oxygen-terminated (110) plane of α-MnO<sub>2</sub>, facilitates\nthe generation of more active oxygen species, and maintains the continuous\ncycling of oxygen-linked Mn<sup>iv</sup>/Mn<sup>iii</sup>. Such dynamics\nare pivotal for stabilizing manganese activation and mitigating the\nJ-T effect. Through a combination of experimental investigations and\ntheoretical calculations, we demonstrate that the Se<sup>iv</sup>-O-Mn<sup>iii</sup> configuration, characterized by a high degree of Mn–O\nhybridization, significantly enhances CO oxidation, NH<sub>3</sub> oxidation, and elemental mercury (Hg<sup>0</sup>) removal performances,\nand exhibits resistance to SO<sub>2</sub>. This study paves the way\nfor the development of efficient low-temperature O<sub>2</sub> activation\nprocesses for the removal of gaseous pollutants in real-world applications.