| Summary: | Dehydrogenation of H<sub>3</sub>COH and H<sub>2</sub>O are key steps of methanol steam reforming on transition metal surfaces. Oxhydryl dehydrogenation reactions of H<i><sub>x</sub></i>COH (<i>x</i> = 0–3) and OH on Ni (111) were investigated by DFT calculations with the OptB88-vdW functional. The transition states were searched by the climbing image nudged elastic band method and the dimer method. The activation energies for the dehydrogenation of individual H<i><sub>x</sub></i>COH* are 68 to 91 kJ/mol, and reduced to 12–17 kJ/mol by neighboring OH*. Bader charge analysis showed the catalysis role of OH* can be attributed to the effect of hydrogen bond (H-bond) in maintaining the charge of oxhydryl H in the reaction path. The mechanism of H-bond catalysis was further demonstrated by the study of OH* and N* assisted dehydrogenation of OH*. Due to the universality of H-bond, the H-bond catalysis shown here, is of broad implication for studies of reaction kinetics.
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