Control synthesis and formation mechanism of sphere-like titanium dioxide

Abstract

Using a simple hydrothermal method without surfactants and templates, different morphologies of titanium dioxide (TiO2) have been synthesised such as nanocubes, nanosheets and microspheres. The effects of the addition of hydrofluoric acid (HF) and hydrogen peroxide (H2O2) in the preparation of TiO2 were studied. It was found that more H2O2 may accelerate the formation of a spherical morphology and that HF has three roles: dissolving Ti powder, retarding the hydrolysis of titanium precursor and reducing surface energy. Reaction time has a significant effect on morphological transformation. The aggregation of microstructures is described, the effects of the addition of HF and H2O2 on the condition of aggregation have been studied. Photocatalysis measurements showed that sphere-like TiO2 consisting of nanocubes exhibited the highest activity for degrading rhodamine B under UV light.