Ethanol adsorption on Ni doped Mo2C(001): A theoretical study

Abstract

Ethanol adsorption on Ni/Mo2C (001) surface at low coverage is studied using Density Functional theory calculations (with van der Waals corrections). The Mo2C surface is modeled from the hexagonal closed-packed (HCP) phase carbide (β-Mo2C). Based on the lower surface energy, we considered the Mo termination and a single Ni as an adatom. The most favorable location for Ni is a FCC site and some charge is transferred from the surface to this atom. Ethanol is then adsorbed on top of this Ni site with − 1.39 eV. The electronic structure (DOS) of Mo2C presents a metallic character and Ni a narrow d band shifted above the Fermi level by the carbide influence. The DOS of ethanol-based states are stabilized to lower energies after adsorption. The most affected are those states from −OH group. A bond is formed between Ni-O at about 2Å while the -OH distance shows an elongation of only 1.7%.