A DFT study on benzene adsorption over a corner site of tungsten sulfides

Benzene adsorption on a model for a corner site of a WS2 slab is considered by periodic DFT calculations. Under typical hydrotreating reaction conditions a fourfold coordination of the corner 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 corner site, replacement of the W atom adjacent to the W corner site by Ni creates a potential adsorption site around the W corner site. Benzene was found to adsorb with ΔE = −0.19 eV on this Ni-substituted model for the corner site of a WS2 slab.