Abstract: Different crystal and crystalline type titania nanoparticles were prepared by using the hydrothermal method and controlling the pH values of solution, ratios of the reactants, temperature and time of hydrothermal reaction. The experimental results show clearly that uniform rod-like titania particles in an average aspect ratio of 4:1 could be obtained under the condition of the pH=11, n(TBOT):n(TEA)=1:2, hydrothermal treatment at 150 ℃ for 48 h. When the pH of the solution was less than 10, spherical titania nanoparticles could be obtained; but when the time was changed to 24 h, spindle titania particles could be obtained. The nanoparticles prepared above are all anatase, but when the pH more than 12, the particles turn to brookite. Phenol in polluted water was used as the degeneration model and the photocatalytical activity of titania with different morphologies was tested in this article.

Key words: TiO₂, Hydrothermal synthesis, Nanoparticle, Anatase, Brookite, Phenol degradation