FT-IR LIQUID ATTENUATED TOTAL REFLECTION STUDY OF TIO2-SIO2 SOL-GEL REACTION

The FT-IR liquid attenuated total reflection (ATR) method was successively used to analyze binary TiO2-SiO2 sol-gel reactions between various titanium alkoxide chelates and three silicon alkoxides of different reactivities at various pH. The homogeneity of the gels was evaluated by the peak intensity of Ti-O-Si band. The stability of hydrolyzed titanium alkoxide chelates against condensation and the reactivity of silicon alkoxide affected the homogeneity, but the stability of titanium alkoxide chelates against hydrolysis did not. Acidic conditions are favorable to form Ti-O-Si bonds, while the hydrolyzed forms of titanium and silicon alkoxides are both stable against homo-condensation.