Diffusion and adsorption of Au and Pt adatoms on ideal and missing row reconstructed surfaces of Au(110): DFT and EAM calculations

摘要

Density-functional theory (DFT) and embedded atom method (EAM) are used to study the adsorption and diffusion on unreconstructed (1 x 1) and reconstructed (1 x 2), (1 x 3) and (1 x 4) surfaces for homogenous Au/Au(110) and heterogeneous Pt/Au(110) systems. Adsorption energies show a strong binding for Pt than Au on all considered geometries. Additionally, adsorption on the (111) microfacet of the (1 x 2), (1 x 3) and (1 x 4) geometries is investigated. Surprisingly the adsorption of Pt on the top hcp sites of the (111) microfacet of the (1 x 2), (1 x 3) and (1 x 4) geometries leads to the exchange phenomenon. The diffusion via hopping and metastable walk is investigated for both the homo and heterogeneous systems. The hopping diffusion barrier show a slight dependence on the reconstruction order and the diffusion is found to be more costly on the missing row reconstructed surface than the unreconstructed surfaces. The potential energy profile for the diffusion via metastable walk mechanism on the (1 x 2) missing row reconstructed geometry indicates that the metastable walk diffusion is more favorable to homogeneous system than to heterogeneous system.