The role of water in photocatalytic dissociation of methanol on rutile TiO2(110)-(1 x 1)

We have performed a surface photocatalysis study of the molecularly adsorbed forms of methanol on a vacuum-annealed rutile TiO2(110)-(1 x 1) surface using temperature-programmed desorption both with and without coadsorbed water to investigate the effect of water and methanol on the photocatalytic dissociation of each other on rutile TiO2(110)-(1 x 1). Our experimental results show conclusively that methanol has no effect on photocatalytic water splitting with water covered rutile TiO2(110)-(1 x 1) surface. Further experimental results also show that water does not affect the process of photocatalytic methanol dissociation but does suppress photo-induced desorption of the formaldehyde product of methanol photocatalysis and can enhance the formation of the methyl formate product. (C) 2014, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved