A simple one-step fabrication of micrometer-scale hierarchical TiO_2 hollow spheres

摘要

Hierarchical TiO_2 hollow spheres had been prepared based on bubble templates by a simple one-step hydrothermal method. The diameter of hollow spheres was about 700 nm and the shell thickness of them was 69 nm. They were composed of similar spindle- or needle-like building units. Furthermore, hydrothermal time had an important influence on the morphology and crystallinity of hollow spheres. Moreover, the UV-Vis diffuse reflectance spectra of TiO_2 hollow spheres heated at 150 ℃ for 10 h showed the strongest absorption in the UV-Vis region and the Raman spectrum demonstrated the anatase sample. Additionally, a possible formation mechanism of TiO_2 hollow spheres was proposed. So this novel and simple method would provide a development direction to fabricate all kinds of inorganic hollow spheres by one-step procedure.