A strategy for single-step elaboration of V2O5-grafted TiO2 nanostructured photocatalysts with evenly distributed pores

V2O5-TiO2 nanostructured porous layers were grown through micro arc oxidation of titanium in vanadate containing electrolytes. This study sheds light on the effect of the electric current type on the photocatalytic performance of the layers. Surface morphology of the layers was investigated by SEM. The results revealed a porous structure with a pores size of 30-180nm depending on the frequency and the duty cycle. A uniform porous structure was obtained under the pulse-DC regime. Topographical investigations revealed a rough surface which is favorable for catalytic applications. Our XRD and XPS results showed that the layers consisted of anatase, rutile, and vanadium oxide phases whose fraction was observed to change depending on the electric variables. Finally, methylene blue was selected as a model material in order to evaluate the photocatalytic performance of the grown layers. The layers which were fabricated under pulse current, especially those synthesized at the frequency of 500 Hz and duty cycle of 5%, exhibited higher photocatalytic efficiency under ultraviolet and visible illuminations on account of their higher surface area and anatase/rutile fraction. (C) 2011 Elsevier B.V. All rights reserved.