Fabrication of TiO2 nanostructured films by spray deposition with high photocatalytic activity of methylene blue

TiO2 films were successfully deposited onto hot quartz substrates by airbrush spraying using an aqueous dispersion. The films consisting of cubic or cauliflower-shaped structures expressed higher photodegradation efficiencies of methylene blue than those with prism-, flower- or fan-blade-shaped morphology due to the difference in the optical band gap energy. The photodegradation obeyed the pseudo-first-order Langmuir-Hinshelwood kinetic model with apparent rate constants ranging from 3.95 x 10(-3) to 19.38 x 10(-3) min(-1) based on the film surface morphology. (C) 2010 Elsevier B.V. All rights reserved.