Theoretical Study on Platinum-catalyzed Isotope Exchange Reaction Mechanism of Hydrogen and Liquid Water

Based on electron and vibration approximate means and the density function theory B3LYP,the ΔG° and equilibrium pressures of adsorption and dissociation reactions of H2 and water vapor on Pt surface have been calculated.The adsorption,dissociation and coadsorption actions of H2 and water were analyzed.According to the ΔG°,hydrogen molecule combines with metal atoms in single atom,and water vapor molecule has no tendency to dissociate on Pt surface.The dissociation of hydrogen molecule would hold back the direct adsorption of water vapor molecules on Pt surface.The structures of Pt-H(OH2)+n(n=1,2,3)hydroniums were optimized.According to the mulliken overlap populations,Pt-H(OH2)+ is not stable or produced.Hydrogen isotope exchange occurs between hydration layer and D atoms which adsorb on Pt surface via intermediates(H2O)nD+(ads)(n≥2)