Alumina phase transformation behavior on titania-doped nano α-alumina by a solid liquid process

摘要

Alumina phase transformation behavior on titania-doped nano α-Al2O3 powder by a solid liquid process was investigated under various conditions, such as different solvent concentrations and calcining temperatures. Three batches of the precursor powders were calcined at three different temperatures of 600 °C, 750 °C and 900 °C for 5 h and a final product of titania-doped nano α-Al2O3 powder was obtained. The product has been identified by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The XRD results show that the alumina phases of the powders were determined to be γ-Al2O3 and α-Al2O3. The optimum calcination temperature of the precursor powder for crystallization of nano α-Al2O3 was found to be 900 °C for 5 h. A higher concentration of solvent used for the sample preparation leads to the formation of a uniform and very smooth particle morphology, and smaller particle grains. The TEM images indicate that the average size of α-Al2O3 grains was ≤ 50 nm and larger grains of TiO2 with 50-250 nm sizes.