Electrolysis of water on oxide surfaces

In this paper, density functional theory (DFT) calculations are performed to analyze the electrochemical water-splitting process producing molecular oxygen (O-2) and hydrogen (H-2). We investigate the trends in the electro-catalytic properties of (110) surfaces of three rutile-type oxides (RuO2, IrO2, and TiO2). The two first of these oxide anodes show lower O-2-evolving over-potentials than metal anodes, due to weak O binding but strong hydroxyl (HO*) binding on the surface. Furthermore, the binding energies of O, HO, and HOO on the (110) surfaces fulfill universal linear relations similar to those found on metal surfaces. (c) 2006 Elsevier B.V. All rights reserved.