Halogen adsorption on Pt(111) and palladium monolayer electrocatalysts: DFT study

Abstract

Adsorption of halogen atoms (Cl, Br and I) on Pt(111), Pd(111) and palladium monolayer electrocatalysts surfaces was investigated using periodic DFT-GGA calculations. The adsorption trends were established and possible consequences of halogen adsorption on the electrocatalytic activity of surfaces were discussed. The nature of halogen-metal bonding was investigated too, using Δd-PDOS analysis. A large covalent contribution in bonding of all three studied halogen atoms was found. Surface mobility of adatoms along the Pd-terminated surfaces was estimated. It was found that the mobility decreases with the increase in surface strain. Finally, for vibrational frequencies of adsorbed halogens, a pronounced dependence on the surface electronic structure was demonstrated. ©The Electrochemical Society.