A DFT study on the adsorption and dissociation of methanol over MoS2 surface

The adsorption and subsequent dissociative reaction of methanol on the bald Mo-edge, 50% Mo-edge, and 50% S-edge of MoSx clusters were investigated by using density functional theory (DFT). The calculation results showed that the adsorption of methanol molecule through its oxygen atom prefers the corner sites to the edge sites of MoSx surfaces. The pathways of methanol dissociation via C-H, C-O and O-H bond scissions are considered and O-H bond scission is found to be the most favorable pathway on the MoS2 surface: the activation barrier is 0.45 eV on the bald Mo-edge and about 1.0 eV on the 50% Mo-edge and 50% S-edge. Among the intermediates formed from methanol dissociation, CH3O is the dominant surface species after the MoS2 surface is exposed to methanol. (C) 2011 Elsevier B.V. All rights reserved.