Ab initio study of interaction between the OH hydroxyl and Ptn (n = 1–10) clusters

The different PtnOH (n = 1–10) models have been calculated by ab initio method. The result shows that the binding energy of the PtOH varies with adsorption sites (atop, bridge and hollow) in range of −1.0 to −10.7 eV. It is also found that there exists strong repulsion among the surface OH species and differently charged hydroxyl species can be formed on the Pt surface (the formal charge varies in range of +0.055 to −0.660). On the basis of the calculation result, it is concluded that the variation of the activation energy with the O2H2 ratio results from the manifold bond strengths of the PtnOH (n = 1–10) and the interaction among the adsorbates (OH), which elucidates the experimental observation very well.