title: The interactions of oxygen with small gold clusters on nitrogen-doped graphene.
abstract: By means of density functional theory, the adsorption properties of O₂ molecule on both isolated and N-graphene supported gold clusters have been studied. The N-graphene is modeled by a C₆₅NH₂₂ cluster of finite size. The results indicate that the catalytic activity and the O₂ adsorption energies of odd-numbered Au clusters are larger than those of adjacent even-numbered ones. The O₂ molecule is in favor of bonding to the bridge sites of odd-numbered Au clusters, whereas for odd-numbered ones, the end-on adsorption mode is favored. The perpendicular adsorption orientation on N-graphene is preferred than the parallel one for Au₂, Au₃ and Au₄ clusters, while for Au₅, Au₆ and Au₇, the parallel ones are favored. When O₂ is adsorbed on N-graphene supported Au clusters, the adsorption energies are largely increased compared with those on gas-phase ones. The increased adsorption energies would significantly facilitate the electron transfer from Au d-orbital to π* orbital of O₂, which would further weakening the O-O bond and therefore enhancing the catalytic activity. The carbon atoms on N-graphene could anchor the clusters, which could make them more difficult to structural distortion, therefore enhance their stability.
authors.affiliation: College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Chen
authors.forename: Shaorui
authors.initials: S
authors.lastname: Sun
authors.forename: Fan
authors.initials: F
authors.lastname: Li
authors.forename: Xiayan
authors.initials: X
authors.lastname: Wang
authors.forename: Dingguo
authors.initials: D
authors.lastname: Xia
mesh_terms: D000327:Adsorption; D006046:Gold / Q000737:chemistry*; D006108:Graphite / Q000737:chemistry*; D008956:Models, Chemical; D008962:Models, Theoretical; D015394:Molecular Structure; D009584:Nitrogen / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry*
chemical_list: D006046:Gold; D006108:Graphite; D009584:Nitrogen; D010100:Oxygen