The synthesis of TiO₂ nanoparticles using sulfuric acid method with the aid of ultrasound

In this study, the authors report the synthesis of titanium dioxide (TiO₂) nanostructures by an ultrasound-assisted method using titanium dioxide particles and sulfuric acid. The synthesis process for titanium dioxide nanoparticles reported herein is simple and easy to reproduce. The structural and microstructural characterizations of titanium dioxide nanoparticles were accomplished using X-ray diffraction, scanning electron microscopy, transmission electron microscopy and Raman scattering spectroscopy. The titanium dioxide nanoparticles were spherical in shape, and the average size of the nanoparticles was in the range of 6–63 nm and depended on the annealing temperature. When the annealing temperature was lower than 650°C, the anatase phase ratio of titanium dioxide was 100%. However, a further increase in the annealing temperature resulted in a rapid increase in the content of the rutile phase. The anatase-to-rutile transformation temperature shifted to a very low level for the nanosize crystallites owing to the high surface energy of the particles. The successful fabrication of titanium dioxide nanosolution will open up new perspectives in the research on modifications and applications of titanium dioxide nanostructures.