中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 22 No. 8 August 2012 |
（1. College of material science and technology, Nanjing University of aeronautics and astronautics,
Nanjing 210016, China;
2. Faculty of Material Science and Engineering, Kunming University of Science and Technology,
Kunming 650093, China）
Abstract:Using Ti powder as reagent, TiO2 nanoneedle/nanoribbon spheres were prepared via hydrothermal method in NaOH solution. The samples were characterized by field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) with selected area electron diffraction (SAED), X-ray diffraction (XRD), and UV-visible light absorption spectrum. The results indicate that the growth orientations of the crystals are influenced by the hydrothermal temperature and NaOH concentration. The diameter of the nanoneedle spheres and nanoribbon spheres (40-50 μm) are almost the same as that of Ti powders. TiO2 nanoneedle/nanoribbon sphere powders are anatase after heat treatment at 450 °C for 1 h. Furthermore, methyl orange was used as a target molecule to estimate the photocatalytic activity of the specimens. Under the same testing conditions, the photocatalytic activities of the products decrease in the following order: TiO2 nanoneedle sphere, TiO2 nanoribbon sphere and P25.
Key words: nano-TiO2; microsphere; photocatalytic properties; hydrothermal synthesis; Ti powders
