Processing and photocatalytic properties of transparent 12 tungsto(VI) phosphoric acid -: TiO2 hybrid films

Using the layer-by-layer method, 12 tungsto(VI) phosphoric acid (PW12) and TiO2 hybrid thin films were prepared. In 2-propanol decomposition, two-bilayer thin films (ca. 15 nm) showed more rapid decomposition than control TiO2 and PW12 films under both UV and Visible light illumination. Visible light illumination was required for continuous 2-propanol decomposition. Photocatalytic decomposition activity depends on the number of bilayer coatings, the top coating, and the organic compounds for decomposition. On the basis of the wavelength dependence of the hybrid thin films, a reaction scheme for this system was discussed.