Photocatalytic degradation of phenol by TiO2 thin films prepared by sputtering

TiO2 thin films were prepared by direct current (dc) reactive sputtering, using various kinds of supports such as glass, silicon, alumina, and glass coated with indium–tin oxide. Samples were characterized by X-ray diffraction (XRD), and atomic force microscopy (AFM). Different TiO2 − x stoichiometries, crystal structures and morphologies were obtained by changing the parameters of the reactive gas. The photocatalytic properties of the samples were tested on the degradation of phenol. The best efficiency in respect with phenol mineralization was obtained for samples prepared using an Ar–H2O mixture as the reactive gas. Indium–tin oxide supports provide the most efficient thin films. The catalytic efficiency per unit area of the sputtered films is at least one order of magnitude better than that of a 50 m2 g−1, reference TiO2 powder.