Modeling oxide-metal interfaces from density-functional theory: Platinum adsorption on tetragonal zirconia

A density-functional-theory- (DFT-) based method for the description of metal-oxide interfaces is presented. By superposition of the potential energy surface (PES) of an isolated metal atom on the oxide surface, predictions can be made for the optimal adsorption mode of arbitrary metal structures. The scheme is tested first for the adsorption of small Pt clusters on a tetragonal zirconia surface. There good agreement with a DFT-calculated PES for the cluster is achieved. The same cluster configuration is investigated for yttrium-stabilized zirconia, too, for which stronger bonding is predicted. Further, the scheme is applied for a Pt film on the same surface, where a complicated root7xroot7 Pt structure on a c(2x2) oxide structure is predicted, in excellent agreement with experimental data.