Adsorption and Diffusion of Oxygen Atom on Pt_3Ni(111) Surface with Pt-Skin

The adsorption and diffusion properties of O atoms on the surface of Pt3Ni(111) with a Pt skin [denoted as"Pt-skin-Pt3Ni(111)"] were studied by the first-principles method based on the density functional theory(DFT).Special attention was paid to the diffusion properties of the adsorbed oxygen on the Pt-skin-Pt3Ni(111) surface as this is important in understanding the high activity of the Pt-skin-Pt3Ni(111) catalyst.We found that O atoms prefered fcc binding sites.Ni atoms in the Pt3Ni catalyst drastically influence the electronic configuration of the system and therefore the binding of oxygen atoms.Nudged elastic band(NEB) calculations were used to determine the diffusion barrier of oxygen atoms on the surface,providing a possible explanation for the distinct catalytic activity of the Pt-skin-Pt3Ni(111) catalyst.