Single O Atom Doped Ag Cluster Cations for CO Oxidation: An O‑Doped Superatom Ag15O+ with Remarkable Stability
journal contributionposted on 25.03.2021, 21:29 by Qiuying Du, Jin Hu, Xiaopeng Xing, Si Zhou, Jijun Zhao
Silver-based materials are reported to have remarkable catalytic activity toward CO oxidation after O2 pretreatment, which are less expensive in comparison with conventional catalysts such as gold and platinum. However, the regulatory role of atomic O that is inevitably present on silver surface remains unclear due to the complicated circumstances in condensed phases. Here we investigated CO oxidation on silver clusters doped by a single O atom AgnO+ (n = 7–11, 15, 19, 22) by experimental mass spectrometry combined with ab initio calculations. We found two types of O species having high cluster size selectivity and determining the oxidation products. A higher d-band center of AgnO+ leads to larger reaction barrier. Remarkably, an extremely stable Ag15O+ superatom with a unique meteor dart structure and satisfying the 18 valence electrons configuration (1S21P61D102S0) was discovered, which is the first reported O-doped transition metal cluster with superatomic character. This work provides important knowledge for balancing the stability and activity of silver-based catalysts at atomic precision for oxidation reactions.