Insight into the promotion effect of pre-covered X (C, N and O) atoms on the dissociation of water on Cu(111) surface: A DFT study

Abstract

Based on the density functional theory together with a periodic model, the adsorption and successive dissociation of water on clean and X (X=C,N and O)-covered Cu(111) surfaces have been investigated systematically. Our results indicate that the doping of carbon, nitrogen and oxygen atoms on the clean Cu(111) surface strengthens the interaction of H2O-surface and weakens the interaction of OH-surface. The corresponding adsorption configurations of adsorbates are slightly changed. Compared to that on clean Cu(111) surface, it is revealed that the doped C, N and O atoms can promote the catalytic activity of H2O dissociation and that the adsorbed C and N atoms are beneficial for the dissociation of OH, namely, the joining of C and N atoms on Cu(111) surfaces improve the catalytic activity and selectivity for H2O complete dissociation. Among four types Cu(111) surfaces, C-covered Cu(111) is the most favorable surface both kinetically and thermodynamically.