Preparation of Porous Anatase Coating from Sol-Gel-Derived Titanium Dioxide and Titanium Dioxide-Silica by Water-Vapor Exposure

• Published in: Journal of the American Ceramic Society Vol. 82; no. 9; pp. 2301 - 2304
• Main Authors: Imai, Hiroaki, Hirashima, Hiroshi
• Format: Journal Article
• Language: English
• Published: Westerville, Ohio American Ceramics Society 01.09.1999; Blackwell; Wiley Subscription Services, Inc
• Subjects: Anatase; Ceramics; Chemistry; Coating; Colloidal state and disperse state; Cross-disciplinary physics: materials science; rheology; Crystallization; Exact sciences and technology; Exposure; General and physical chemistry; Liquid phase epitaxy; deposition from liquid phases (melts, solutions, and surface layers on liquids); Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Physics; Porous materials; Silicon dioxide; Titanium dioxide; Water vapor; Inorganic compounds; Anatase; Porous materials; Transition element compounds; Crystallization; Binary compounds; Experimental study; Coatings; Thin films; Titanium oxides; Composite materials; Silicon oxides; Steam; Sol-gel process; Growth from solution
• ISSN: 0002-7820; 1551-2916
• DOI: 10.1111/j.1151-2916.1999.tb02083.x

The effects of water vapor on the crystallization behavior of sol‐gel‐derived titanium dioxide (TiO2) thin films that contained 0‐50 mol% silica (SiO2) were investigated. Anatase formed on exposure to water vapor at 60°‐180°C, with a simultaneous decrease in the concentration of OH groups. An increase in the SiO2 content of the exposed films led to an increase in the average crystalline size. Because crystallization of the exposed films of the films was not accompanied by shrinkage, porous anatase coatings were obtained via exposure at a relatively low temperature. Phase separation of the immiscible TiO2‐SiO2 system was induced with water vapor, which resulted in acceleration of the crystallization of the sol‐gel films.