High coverage water adsorption on the CuO(111) surface

Graphical abstract: Mixed H₂O molecular and dissociative coadsorption is favorable on CuO(111) surface at high coverage. - Highlights: • DFT+U calculation and atomic thermodynamics was used to study H₂O adsorption on CuO(111) surface. • H₂O molecule can chirally adsorb on CuO(111) surface. • Probability distribution was analyzed as function of temperature for single adsorbed water. • Phase diagram of water adsorption on CuO(111) surface is predicted at different temperature and water pressure. - Abstract: Water adsorption on the CuO(111) surface at different coverage has been systematically studied by spin-polarized density functional theory calculations (GGA+U) and atomic thermodynamics. Both molecular and dissociative adsorptions are studied. It is found that H₂O molecule can chirally adsorb on CuO(111) surface which maybe play an important role in catalysis field. Molecular H₂O adsorption is preferred for one H₂O molecule, while mixed molecular and dissociative coadsorption is preferred on CuO(111) surface for two, three and four H₂O molecules. Molecular and dissociative H₂O adsorption can coexist at high temperature by using Boltzmann statistics. The phase diagram shows that only three surface configurations are stable thermodynamically: clean CuO(111) surface, two H₂O and four H₂O adsorption. The surface uncoordinated copper and oxygen atoms, and hydrogen bonding contribute to the adsorption energies. H₂O adsorption mechanism has been analyzed by projected density of states (PDOS).