Low Temperature Synthesis of TiO2 Nanoparticles with Tuneable Phase Composition and their Photocatalytic Activity

The effect of TiCl4 concentration on the phase transformations among the TiO2 polymorphs was studied using in situ powder X-ray diffraction and Raman spectroscopy. Interestingly, the primarily amorphous TiO2 solid obtained after thermolysis of TiCl4 at 80°C contained some anatase and rutile phases for low (≤18 mM) and high (≥27 mM) TiCl4 concentrations, respectively. These samples produced anatase or rutile dominated samples of TiO2 after hydrothermal treatment. The tricrystalline TiO2 sample fabricated with 18 mM TiCl4 solution showed the highest photocatalytic activity for the degradation of phenol, as a result of high surface area.