Theoretical Study of Methanol Oxidation on the PtAu(111) Bimetallic Surface: CO Pathway vs Non-CO Pathway

By performing density functional theory calculations, we have studied the CO pathway and non-CO pathway of methanol oxidation on the PtAu(111) bimetallic surface. CO is shown to possess larger adsorption energy on the PtAu(111) surface than that on the pure Pt(111) surface, and the non-CO pathway on the bimetallic surface is found to be energetically more favorable than the CO pathway. These calculated results propose that the improved electrocatalytic activity of PtAu bimetallic catalysts for methanol oxidation should be attributed to the alternation in the major reaction pathway from the CO pathway on the pure Pt surface to the non-CO pathway on the PtAu bimetallic surface rather than the easier removal of CO on PtAu catalysts than on pure Pt catalysts.