Density Functional Theory Study of the Adsorption of Nitrogen and Sulfur Atoms on Gold (111), (100), and (211) Surfaces

Abstract

Nitrogen and sulfur atom adsorption on flat and stepped gold surfaces are examined by density functional theory. With detailed investigation of adatom location on the (111), (100), and (211) gold surfaces, nitrogen and sulfur atom adsorption are compared with reference to previous work on the oxygen/gold system. Sulfur adsorbed most strongly, followed by oxygen and nitrogen. The results demonstrate the preference for 3-fold over 2-fold and single-fold adatom coordination as well as the role of low coordinated gold surface atoms in increasing the adsorption energy for nitrogen, sulfur, and oxygen atoms. Pseudopotential curves, calculated adsorption energy as a function of surface position, and nudged-elastic band calculations explored adatom diffusion along the surface. The results indicated limited diffusion on the (111) and (211) surfaces. On the other hand, while nitrogen and sulfur atoms remained localized on the (100) surface, oxygen atoms showed facile diffusion. These results provide a reference for...