First-principles Theoretical Study of Hydrogen Bond Induced NO Dissociation on the Cu(110) Surface

Abstract

In this work, by mean of a plane-wave pseudopotential density functional theory method, we study the physical insights of NO dissociation on the Cu(110) surface and the promotion of NO dissociation by hydrogen bond coupling. Using the climbing-image nudged elastic band method, we find that the hydrogen bond from water molecules reduces the NO dissociation energy barrier significantly. We perform the orbital overlap population analysis, namely Projected Density of State (PDOS) onto molecular orbitals of the adsorbates and Crystal Orbital Overlap Population (COOP) together with the Bader charges to clarify the electronic structure evolution of NO during the dissociation pathway. Our results reveal that NO dissociation on copper surface is enhanced by Π back donation from Cu(110) surface. The bond of NO is broken as the results of 2Π∗ orbital filling. The significant reduction of the energy barrier with the existence of water molecules is promoted by the induction of 2Π∗ orbital filling from the hydrogen bond coupling. Our results are consistent and support the observations of scanning tunneling microscopy experiment.