Ab initio study of the adsorption of 3d transition metals on Ni(100) surface

Abstract

Nickel based catalysis has shown high activity, selectivity and stability more than mono-Ni surface catalysis in energy and environmental applications. First principle calculations based on Density Functional Theory and the Generalized Gradient Approximation are performed to investigate the structural, electronic, and magnetic properties of M/Ni(100); M=Fe, Co, and Cu systems at 0.25, 0.50 and 1.00 monolayer coverage. Ferromagnetic (FM) configuration is found to be more stable than non-magnetic configuration for all studied elements. Adsorption of Fe and Co on Ni(100) surface enhances the FM properties of admetal and substrate at all coverage. Whereas, Cu decreases the FM properties of the topmost Ni(100) surface atom and kept almost non-magnetic. The d band center is calculated for the admetal and topmost Ni surface atom at all coverages. The obtained results are explained by Hammer-Nørskov model to predict the change on the reactivity of Ni surface by adding the adsorbed metals. The calculations reveal that there is no clear relationship between the d band-center and the magnetic moments of the Ni surface layer.