Catalysis Today, Vol.130, No.1, 178-182, 2008
A DFT study on benzene adsorption over a corner site of tungsten sulfides
Benzene adsorption on a model for a comer site of a WS2 slab is considered by periodic DFT calculations. Under typical hydrotreating reaction conditions a fourfold coordination of the comer W atom is thought to be more favorable for benzene adsorption than five- or sixfold coordinated W atoms in conventional edge surfaces. Although no benzene adsorption site was identified on such a comer site, replacement of the W atom adjacent to the W comer site by Ni creates a potential adsorption site around the W corner site. Benzene was found to adsorb with Delta E = -0.19 eV on this Ni-substituted model for the comer site of a WS2 slab. (C) 2007 Published by Elsevier B.V.
Keywords:benzene;adsorption;tungsten sulfides (WS2);hydrogenation (HYD);density-functional theory (DFT);pseudo-corner site;fourfold coordinated tungsten