Trends and Regularities for Halogen Adsorption on Various Metal Surfaces

Abstract

Work function changes induced by adsorbates play an important role in electrochemistry, where specially adsorbed ions directly influence the electrode potential through this parameter. Systematic density functional theory calculations were performed for fluorine, chlorine, bromine, and iodine adsorption on 29 close-packed metal surfaces. Through a large number of calculations, it was shown that similar geometry adsorption sites have very good linear relationships in terms of adsorption energies, the vertical distances between halogen atoms and the metal surfaces, the Bader net charges of the adsorbates, and the induced work function changes. Additionally, there is a linear relationship between bromine and chlorine for these surface properties. The fact that nearly half of the cases we investigated exhibit the work function decrease behavior indicates its generality in halogens adsorption situations.