A first-principles study of Pt-Ni bimetallic cluster adsorption on the anatase TiO_2 (101) surface: Probing electron effect of Ni in TiO_2 (101 )-bimetallic cluster (Pt-Ni) on the adsorption and dissociation of methanol

摘要

A density functional theory (DFT) based method in conjunction with the projector augmented wave and pseudopotential methods have been applied to investigate the adsorption of Pt_4 and Pt_3Ni on the anatase TiO_2 (101) surface. Two stable Pt_3Ni adsorptions with considerable adsorption energies on the anatase TiO_2 (101) surface were identified. Analysis of the partial density (PDOS) of states and Bader charge suggest that the electronic structure of Pt is modified by Ni due to the electron transfer from Ni to Pt atoms in the Pt_3Ni clusters. The 2cO (3cO)-PtNi-5cTi conformation of the adsorbed Pt_3Ni on the anatase TiO_2 (101) surface provides a more feasible model for electron injection through the Pt_3Ni/TiO_2 interface. The reactivity of Pt_3Ni/TiO_2 is superior to Pt_4/TiO_2 and effectively manifests itself in the eased decomposition of O-H bonds derived by methanol and alleviative CO adsorption.