The effect of mechanochemical, microwave and hydrothermal modification of precipitated TiO2 on its physical-chemical and photocatalytic properties

Abstract The effects of the microwave (MWT), hydrothermal (HTT) and mechanochemical treatments (MChT) on the structure and physicochemical properties of TiO2 precipitated from titanium sulfate and chloride were investigated. The obtained materials were characterized using the N2 adsorption/desorption, XRD and XRF analysis, FTIR and UV-Vis spectroscopy. Photo- and mechanocatalytic properties of the samples were also studied as regards the rhodamine B (RhB) degradation in the aqueous solution. All types of treatment cause significant changes in the porous structure of the samples. The XRD results showed the improvement of crystalline structure during MWT and HTT. As follows from the investigations, each way of modification results in the shift of the absorption edge towards higher wavelength values and promotes an increase in the photocatalytic activity in the process of rhodamine B degradation under visible irradiation. For the mechanocatalytic degradation, the antibate dependence of the rate constant of RhB degradation on the specific surface area of catalysts was established.