Photocatalytic activity of porous anatase layers monitored with the linear optical response

The photocatalytic activity of different porous layers of anatase nanocomposites; has been monitored by measuring changes of the optical response of Rhodamine 6G water solution under UV irradiation in the presence of anatase films. We have produced series of porous anatase films with different methods to investigate their photocatalytic activity and its dependence on the parameters of the layers. Integrated sphere transmission and reflection spectra (200 - 1000 mn) with 3D angular resolved light scattering data gave a possibility to estimate the correct intrinsic absorption coefficient, the dispersion of the refractive index, the porosity (32 - 39 %) and the thickness (90 - 1340 nm) of the samples. We have estimated the energy of the optical band-gap for both direct (3.66 - 4 eV) and indirect (3.33 - 3.4 eV) transitions. It has been shown that the photocatalytic activity depends sensitively on the nanopores which is determined by the molecular weights of pore agents.