摘要 |
Provided is a synthesis method for acicular titanium oxide powder that has excellent temperature stability in the crystal phase thereof. It is possible to synthesize acicular titanium oxide powder that has excellent temperature stability in the crystal phase thereof by: synthesizing (step 1) an acicular alkali-Ti-oxide as an intermediate, by using a strong alkali aqueous solution and performing hydrothermal synthesis in a range greater than or equal to 375°C and 22.5MPa, which is in the supercritical state of water; and heat-treating (step 2) the acicular alkali-Ti-oxide, the intermediate obtained in the previous step, by exchanging the alkali ions with hydrogen ions in a mildly acidic aqueous solution, and then heat-treating at a temperature of 300-500°C in the atmosphere. It is preferable for the temperature and pressure ranges during the hydrothermal synthesis to be 375-430°C and 22.5-40MPa, and for the concentration in the strong alkali aqueous solution to be 8-13 mol/L. |