Synergy between monomer oxygen vacancies and oxygen vacancy clusters in MnO₂ enables efficient catalytic...

Direct catalytic decomposition is a promising method to alleviate the greenhouse gas N₂O. Transition metal oxides are competitive candidates, but their satisfactory catalytic efficiency is often constrained by the accumulation of intermediate oxygen species (*O₂). Here, we devised dual-active sites to isolate N₂O activation and *O₂ desorption instead of single-active sites responsible for these two steps. Based on the differences in the crystal structures of MnO₂, we synthesized a dual-active site catalyst (MnO₂-600) composed of monomer oxygen vacancies and oxygen vacancy clusters, as well as a single-active site catalyst (MnO₂-0) consisting solely of monomer oxygen vacancies. Experimental and theoretical analyses indicate that the oxygen vacancy clusters in MnO₂-600 are effective sites for N₂O adsorption and activation, whereas monomer oxygen vacancies accelerate the rapid desorption of *O₂ species owing to their low oxygen desorption energy. As demonstrated, MnO₂-600 with dual-active sites exhibited improved reaction activity, achieving up to 90 % N₂O conversion at 386 °C, which is 100 °C lower than that of MnO₂-0 with single-active sites. This study proposes a strategy to promote the catalytic decomposition of N₂O by constructing synergistic dual-active sites, and provides an important extension of defect engineering.