The adsorption and dissociation of H2O on clean TiO2(110) and metal-deposited W TiO2(110) (M = Pt and Au) surfaces were studied by performing calculations of periodic density-functional theory. M/TiO2(110) surfaces catalytically decompose H2O with barriers (decreased by ca. 15-19 kcal/mol) much smaller than for their clean TiO2(110) counterparts. The Au-deposited TiO2 surface has the least energy barrier (ca. 3.5 kcal/mol less than the Pt analogue), explicable with a Bader charge analysis. (C) 2009 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.