DFT Study on CO Oxidation Catalyzed by PtmAun (m + n = 4) Clusters: Catalytic Mechanism, Active Component, and the Configuration of Ideal Catalysts

• DOI: 10.1021/jp101470c
• Publication Date: 2010-08-03T17:43:17Z
• Authors: Fang Wang; Dongju Zhang; Yi Ding
• Keywords: Bimetallic strip; Active center; Peroxide

By performing density functional theory calculations, we show the mechanism details of CO oxidation catalyzed by several PtmAun (m + n = 4) clusters. It is found that in all situations, reaction prefers to proceed via single-center pathway two-center according a two-step mechanism: initial activation O2 molecule form peroxide-like intermediate followed rupture peroxide bond complete reaction. In Pt−Au bimetallic clusters, Pt sites are catalytically active centers, whereas Au "formally spectators" for oxidation. The calculated barriers reactions mediated clusters Pt3Au, Pt2Au2, PtAu3, comparable with monometallic Pt4 cluster, implying catalytic activity centers seems not be dependent on its surroundings. On basis present results, propose an ideal configuration catalysts, where each atom suitably spaced (stabilized) atoms. Such catalysts "less expensive and more efficient" compared corresponding pure at room temperature.