Autocatalytic Water Dissociation on Cu(110) at Near Ambient Conditions

Autocatalytic dissociation of water on the Cu(110) metal surface is demonstrated on the basis of X-ray photoelectron spectroscopy studies carried out in situ under near ambient conditions of water vapor pressure (1 Torr) and temperature (275−520 K). The autocatalytic reaction is explained as the result of the strong hydrogen-bond in the H2O−OH complex of the dissociated final state, which lowers the water dissociation barrier according to the Brønsted−Evans−Polanyi relations. A simple chemical bonding picture is presented which predicts autocatalytic water dissociation to be a general phenomenon on metal surfaces.