Adsorption and dissociation of H2O monomer on ceria(111): Density functional theory calculations

Abstract

The adsorption properties of isolated H2O molecule on stoichiometric and reduced ceria(111) surfaces are theoretically investigated by first-principles calculations and molecular dynamics simulations. We find that the most stable adsorption configurations form two hydrogen bonds between the adsorbate and substrate. The water molecule is very inert on the stoichiometric surface unless up to a high temperature of 600 K. For the reduced surface, we find that the oxygen vacancy enhances the interaction. Moreover, simulations at low temperature of 100 K confirm that it is facilitated for water to dissociate into H and OH species.