Theoretical study on water behavior on the copper surfaces.

We calculated the adsorption of H, O, OH, and H2O and the dissociation of H2O molecule on the Cu(111), Cu(100), and Cu(110) surfaces using density functional theory. H, O, and OH tend to adsorb stably at the highly coordinated dh and h sites on the Cu(111) and Cu(100) surfaces. OH and H tend to adsorb on sb site on the Cu(110) surface. The more charge transfer of the adsorbed substance, the more stable the adsorption. The dissociation product is O+H on the Cu(111) surface, while the dissociation product is OH+H on the Cu(100) and Cu(110) surfaces. Due to the different geometric structures of initial state (IS), transition state (TS), and final state (FS) in the dissociation reaction, the dissociation of water on the copper surface does not establish a linear Brønsted-Evans-Polanyi (BEP) relationship. These results provide theoretical support for the understanding of the interaction between water and metals as well as the behavior of water molecules.