Activation of CO over Ultrathin Manganese Oxide Layers Grown on Au(111)

作者：Yifan Li, Le Lin, Rentao Mu, Yijing Liu, Rankun Zhang, Chao Wang, Yanxiao Ning, Qiang Fu, Xinhe Bao · 发表于：ACS Catalysis · 年份：2021 · DOI：10.1021/acscatal.0c04302 · 被引用次数：36 · 研究领域：Catalytic Processes in Materials Science、Catalysis and Oxidation Reactions、Magnetic and transport properties of perovskites and related materials

Well-defined manganese oxide (MnO x ) overlayers with a controlled chemical state and coverage were deposited on Au(111), and CO activation at the model MnO x / Au(111) surfaces was explored by combining treatments in high-pressure (up to 100 mbar) CO at elevated temperatures and in situ surface characterizations. We find that all MnO x nanostructures transformed into reduced MnO states (MnO 1– y, 0 < y < 1) in the near-ambient pressure CO atmosphere, and dissociation of CO to carbon deposit occurs above 473 K. A volcano curve of the carbon deposit amount as a function of MnO coverage is clearly presented, indicating that MnO island edges are the active centers. Density functional theory calculations show that MnO/Au(111) interfaces provide edge Mn atoms coordinated with two oxygen atoms, where CO disproportionation occurs facilely through the CO dimer and further CCO* intermediates.