Abstract
Nanocrystalline TiO2 is of great interest owing to its potential applications in many aspects such as solar energy conversion, photocatalysis, sensors, and photochromic devices. Among the diferent synthetic approaches developed in the last few years, the nonhydrolytic processes is particularly successful to synthesize crystalline TiO2. In spite of the progress, the synthesis of nanocrystalline TiO2 remains time- and energy-consuming. One possibility to accelerate the synthetic process is the use of microwave irradiation, which allows a more e?cient and homogeneous heating of the reaction mixture. Microwave-assisted synthesis routes for inorganic materials are not yet as popular as for organic compounds. In this study, the nonhydrolytic sol̈gel chemistry was combined with microwave heating to synthesize highly crystalline TiO2 nanoparticles in good yields within 3 hours. Several parameters including temperature, reaction time and the ratio of titanium precursor to solvent were found to influence the properties of TiO2. The synthesized titanium dioxides are further characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), scanning electron microscope (SEM), N2 adsorption and desorption. From XRD results, the TiO2 nanocrystallines are mainly anatase phase with the grain size of 5.7 nm. The specific surface area is about 150 m2/g. Electron microscopic images demonstrated that the TiO2 nanoparticles are near monodisperse. In addition, the photocatalytic activity of TiO2 was examined by using methylene blue as the target compound. A good photodegradation efficiency was obtained when 10 mg/L methylene blue was illuminated with 305 nm UV light.