Photocatalytic degradation of phenol by TiO2 thin films prepared by sputtering

TiO2 thin films were prepared by direct current (dc) reactive sputtering, u sing various kinds of supports such as glass, silicon, alumina, and glass c oated with indium-tin oxide. Samples were characterized by X-ray diffractio n (XRD), and atomic force microscopy (AFM). Different TiO2-x stoichiometrie s, crystal structures and morphologies were obtained by changing the parame ters of the reactive gas. The photocatalytic properties of the samples were tested on the degradation of phenol. The best efficiency in respect with p henol mineralization was obtained for samples prepared using an Ar-H2O mixt ure as the reactive gas. Indium-tin oxide supports provide the most efficie nt thin films. The catalytic efficiency per unit area of the sputtered film s is at least one order of magnitude better than that of a 50 m(2) g(-1), r eference TiO2 powder. (C) 2000 Elsevier Science B.V. All rights reserved.