Preparation of Titania from Tetrakis(diethylamino)titanium via Hydrolysis

• Published in: Journal of sol-gel science and technology Vol. 19; no. 1-3; pp. 365 - 369
• Main Authors: Ishikawa, Yoshizumi, Honda, Hideyasu, Sugahara, Yoshiyuki
• Format: Journal Article
• Language: English
• Published: New York Springer Nature B.V 01.12.2000
• Subjects: Amorphous materials; Anatase; Brookite; Crystallization; Hydrolysis; Roasting; Tetrahydrofuran; Titanium; Titanium dioxide
• ISSN: 0928-0707; 1573-4846
• DOI: 10.1023/A:1008718723502

The conversion of tetrakis(diethylamino)titanium (Ti(NEt2)4) into titania via either a combination of hydrolysis (Ti(NEt2)4 : THF : H2O = 1 : 10 : x, x = 2, 4, 10) at ambient conditions and calcination (method A) or hydrolysis in a water-tetrahydrofuran (THF) mixture (Ti(NEt2)4 : THF : H2O = 1 : 10 : 100) at reflux (method B) was investigated. Titanium tertiary butoxide (Ti(OtBu)4) was also used as a substitute for Ti(NEt2)4. The hydrolysis via method A resulted in the formation of amorphous solids containing organics. Thermal analyses showed that the hydrolysis products showed mass losses up to 500°C probably due to the presence of diethylamine (Et2NH) formed via the hydrolysis of Ti(NEt2)4 in the hydrolysis products, while a mass loss of the hydrolysis product from Ti(OtBu)4 was completed up to about 200°C. After calcination at ≥600°C, anatase or a mixture of anatase and rutile was obtained. The crystallization behavior of the hydrolysis products from Ti(NEt2)4 was different from that of the hydrolysis product from Ti(OtBu)4. The hydrolysis via method B gave only an amorphous material from Ti(NEt2)4, while a crystalline titania (anatase and brookite) formed from Ti(OtBu)4.