Preparation of ultrafine crystalline TiO2 powders from aqueous TiCl4 solution by precipitation

다국어 초록 (Multilingual Abstract)

Ultrafine crystalline TiO_(2) powders were prepared by just heating and stirring aqueous TiOCl_(2), solution with a Ti^(+4) concentration of 0.5 mol/ℓ at room temperature to 100℃ under one atmosphere. The crystallinity, the phase transformation and the particle shape of ultrafine TiO_(2) powders obtained by this simple precipitation method were analyzed using an X-ray diffractometer (XRD). transmission electron microscopy (TEM), differential thermal analyzer (DTA), and scanning electron microscope (SEM). TiO_(2) crystalline precipitates with a pure rutile phase were formed below 65℃. then TiO_(2) crystalline precipitates with an anatase phase started forming at temperatures higher than 65℃. which ends with the pure anatase phase at 100℃. The direct formation of TiO_(2) crystalline precipitates from an aqueous TiO_(2) solution is due to the existence of the OH- ions in distilled water which cause the crystallization of TiOCl_(2) to TiO_(2) without hydrolyzation to Ti(OH)_(4). Conventionally, rutile-phase TiO_(2) is obtained at much higher temperatures. However, in this study a stable rutile-phase TiO_(2) was obtained by a simple method at close to room temperature.

목차 (Table of Contents)

• 1. Introduction
• 2. Experimental Procedure
• 3. Results and Discussion
• 4. Conclusions