title: Nitrogen monoxide adsorption on Pt4 clusters coated on gamma-Al2O3 (111) surface.
abstract: The nitrogen monoxide (NO) adsorption on platinum tetramer (Pt4) clusters supported on gamma alumina (gamma-Al2O3) with surface index (111) was investigated by using ab-initio calculation based on density functional theory. The Pt4 geometries used in this study are tetrahedron and planar rhombus. The adsorption of Pt4 on gamma-Al2O3 (111) surface in tetrahedron configuration is energetically more favorable as compared to that of the planar rhombus. However, it was found that NO molecule adheres strongly to Pt4 with planar configuration on gamma-Al2O3(111) surface. In addition, the NO adsorption calculation on the isolated Pt4 clusters also shows similar preference to planar configuration. The local density of states (LDOS) reveals that the difference in reactivity comes from the different hybridization strengths between the electronic states of nitrogen atom and those of platinum tetramers. The results are in good agreement with the experiments which show similar tendency for CO and N2O reactivity to gas-phase platinum clusters.
authors.affiliation: Department of Applied Physics, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
authors.forename: Ferensa
authors.initials: F
authors.lastname: Oemry
authors.forename: Mary Clare
authors.initials: MC
authors.lastname: Escano
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Kishi
authors.forename: Shinichi
authors.initials: S
authors.lastname: Kunikata
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nakanishi
authors.forename: Hideaki
authors.initials: H
authors.lastname: Kasai
authors.forename: Hiroyoshi
authors.initials: H
authors.lastname: Maekawa
authors.forename: Kazuo
authors.initials: K
authors.lastname: Osumi
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Tashiro
mesh_terms: D000327:Adsorption; D000537:Aluminum Oxide / Q000737:chemistry*; D003198:Computer Simulation; D008956:Models, Chemical; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D009569:Nitric Oxide / Q000737:chemistry*; D010984:Platinum / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D009569:Nitric Oxide; D010984:Platinum; D000537:Aluminum Oxide