Density functional study of hydrazine adsorption and its N-N bond cleaving on Fe(110) surface

摘要

We report density-functional-theory-based calculations of hydrazine adsorption and its N-N bond cleaving on clean Fe(110) surface. It is found that hydrazine may adopt several adsorption configurations among which the most energetically stable is the bridging configuration. Adsorption on short bridge site generally has larger adsorption energies than those on long bridge site. N-N bond cleaving is an exothermic process with reaction energies of 1.90 and 1.67 eV on long and short bridge site, respectively. Nudged elastic band method is used to estimate the activation energies of N-N bond cleaving. Our results indicate that N-N bond cleaving on long bridge site has lower activation energy (0.27 eV) compared to that of short bridge site (036 eV). By examining the molecular orbitals of the initial state it is found that this difference stems from stronger bond between the two NH2 fragments adsorbed on short bridge site as compared to long bridge. (C) 2015 Elsevier B.V. All rights reserved.