FENG Guo ¹, BAO Yi ¹, JIANG Weihui ^{1, 2, 3}, LIU Jian min ¹, ZHANG Quan ¹, WU Qian ¹, MIAO Lifeng ¹,
(1. National Engineering Research Center for Domestic & Builing Ceramics, Jingdezhen Ceramic Institute, Jingdezhen 333001,
Jiangxi, China; 2. Department of Material Science and Engineering, Jingdezhen Ceramic Institute, Jingdezhen 333403,
Jiangxi, China; 3. Jiangxi Key Laboratory of Advanced Materials, Jingdezhen 333001, Jiangxi, China)

Abstract: Aluminum titanate films were coated on silicon carbide substrate via non-hydrolytic sol-gel (NHSG) method and citric acid assisted sol-gel method at 750 °C. These films were characterized by XRD and FE-SEM, and the sol-gel transition processes of these two preparation methods were studied by means of FT-IR. It is found that uniform, compact aluminum titanate films without defects can be prepared via both non-hydrolytic sol-gel method and citric acid-assisted sol-gel method at 750 °C. The sol-gel transition process of the NHSG method is that titanium chloride and anhydrous aluminum chloride react with ethanol and form sol which contains chlorinated titanium alkoxide and chlorinated aluminum ethoxide that are further polycondensed into gel with Al-O-Ti bond in the process of the films drying at 110 °C. And the sol-gel transition process of the citric acid-assisted sol-gel method is that aluminum and titanium precursors first hydrolyze with the inhibition of citric acid until the polarity of the intermediates hold it up, and they form a sol. Then the non-hydrolytic condensation reaction occurs with the formation of Al-O-Ti bond in the 110 °C drying process of film to form the gel.

Key words: aluminum titanate; film; non-hydrolytic sol-gel method; citric acid assisted sol-gel method; sol-gel transition process,