Density functional theory (DFT) investigation of the adsorption of the CH3OH/Au(100) system

The adsorptionofmethanol onflat Au (100) surfacewith different coverages (theta = 1.0, 0.5 and 0.25monolayer (ML)) is studied using density functional theory. Among the three sites (top, bridge and hollow) and coverages investigated in the present work, no adsorption is stable for theta = 1.0 ML. The most energetically preferred site of adsorption for CH3OH is found to be the hollow site for coverages of 0.25 ML and 0.50ML. We also find that for all adsorption sites, an increase in CH3OH coverage triggers a decrease in the adsorption energy. The geometric parameters, local density of states and work function changes are analysed in detail. The coadsorption ofmethoxy and hydrogen has also investigated. In addition, the dissociation ofmethanol on Au(100) has been studied, and an activation energy was found to be 1.72 eV. This result compare with existing data in the literature for Au(111) surface. Copyright (C) 2013 John Wiley & Sons, Ltd.