title: CO oxidation at the perimeters of an FeO/Pt(111) interface and how water promotes the activity: a first-principles study.
abstract: The catalytic role of the Pt--Fe cation ensemble presented at the perimeters of the FeO film supported on Pt(111) for low-temperature CO oxidation and the promotion of water on activity were studied by using DFT calculations. We found that the perimeter sites along the edge of the FeO islands on Pt provided a favorable ensemble that consisted of coordinatively unsaturated ferrous species and nearby Pt atoms for O(2) and H(2) O activation free from CO poison. A dissociative oxygen atom at the Pt--Fe cation ensemble reacts easily with CO adsorbed on nearby Pt. The OH group from water dissociation not only facilitates activation of the oxygen molecule, more importantly it opens a facile reaction channel for CO oxidation through the formation of the carboxyl intermediate. The presence of the OH group on the FeO film strengthens interfacial interactions between FeO and Pt(111), which would make the FeO film more resistant to further oxidation. The importance of the Pt--Fe cation ensemble and the role of water as a cocatalyst for low-temperature CO oxidation is highlighted.
authors.affiliation: State Key Laboratory of Catalysis and Center for Theoretical and Computational Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Zhongshan Road 457, Dalian 116023, PR China.
authors.forename: Xiang-Kui
authors.initials: XK
authors.lastname: Gu
authors.forename: Runhai
authors.initials: R
authors.lastname: Ouyang
authors.forename: Dapeng
authors.initials: D
authors.lastname: Sun
authors.forename: Hai-Yan
authors.initials: HY
authors.lastname: Su
authors.forename: Wei-Xue
authors.initials: WX
authors.lastname: Li
mesh_terms: D000327:Adsorption; D002248:Carbon Monoxide / Q000737:chemistry*; D005290:Ferric Compounds / Q000737:chemistry*; D006878:Hydroxides / Q000737:chemistry; D008958:Models, Molecular; D008968:Molecular Conformation; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry; D010984:Platinum / Q000737:chemistry*; D014867:Water / Q000737:chemistry*
chemical_list: D005290:Ferric Compounds; D006878:Hydroxides; D014867:Water; C000499:ferric oxide; D010984:Platinum; D002248:Carbon Monoxide; C031356:hydroxide ion; D010100:Oxygen