Role of hydrothermal temperature on crystallinity, photoluminescence, photocatalytic and gas sensing properties of TiO2 nanoparticles

TiO2 nanoparticles were synthesised by hydrothermal method. The degree of crystallinity and phase purity were confirmed from the Raman spectra and X-ray diffraction. By increasing the hydrothermal temperature, crystallinity and AC conductivity of the TiO2 nanoparticles increase. Nitrogen adsorption-desorption measurements confirmed that the samples were mesoporous with an average pore diameter of 4.4-7.45 nm. Photocatalytic activity of TiO2 nanoparticles was evaluated and the sample hydrothermally treated at 160 degrees C has the highest photocatalytic activity. In gas sensing measurements, sensitivity increases as a function of concentration and the response to ethanol vapour was better compared to other gases for the sample synthesised at 160 degrees C.