Key Factors on Preparing Superfine Dispersed Spherical TiO 2 Particles by Hydrolysis

The superfine dispersed spherical particles of TiO 2 was prepared by hydrolysis method. The morphology, the size, the crystalline of the partical, were measured by X-ray diffraction and TEM. The effect of anions, pH, concentration of reactant, aging on the formation of spherical particle was studied systematically. The formation domain of spherical particle was given. It is shown that the change of reactant concentration and pH cause the variety of particle shape. The lower concentration, the lower pH values (higher acidty), the easier the formation of spherical particles. When a trace sulfate ion was added to the solution that is in the spherical domain, The spherical particles cann't be gotten. Only the smaller, non-spherical particles can be found. The aging at room temperature was effective to the dispersal. On aging the particles tends to become smaller and well dispersal. The impact of different calcining temperature on the size, morphology and crystalline was investigated. The higher the calcining temperature, the higher the rutile content, and the more dispersion. In this experiment, rutile, spherical and well dispersed TiO 2 particles about 2μm were obtained.