Preparation and characterisation of TiO2 thin films with special optical properties

Thin films of TiO2 were coated onto optical glass substrate from a medium containing metal alkoxide precursors, chelating agent and solvents. In order to prepare TiO2 films with controllable porosity or special optical properties, polyethylene glycol and europium nitrate were added into the coating bath. Multiple TiO2 layers were deposited by dip-coating method and they were annealed in air, at 550 degrees C. Thermal analysis, FT-IR spectroscopy and surface area measurements were used to characterise the precursor powders. The optical properties of TiO2 films were studied by UV-Vis absorption/reflection spectroscopy and photoluminescence measurements while the film morphology was evaluated by scanning electronic microscopy (SEM).