Nanocrystallite Titanium Dioxide Films Made by the Sol-Gel Method Using Reverse Micelles

Reverse micelles have been made by dissolving Triton X-100 in cyclohexane and adding water. Titanium isopropoxide was then introduced in the solution under vigorous stirring yielding a clear sol. If left at ambient temperature the sol gels in a time of a few hours. Gelation has been studied by fluorescence probing. When a glass slide was dipped in the sol at an early stage of gelation, a thin, photometrically uniform film formed, containing both TiO2 and surfactant. The organic substances could then be burned out at 400–450°C. Heating secured total TiO2 formation and permanent attachment to the glass substrate. The ensuing film was studied by electron and AFM microscopy. The film possessed a mesoporous structure characterized by uniformity and particle size monodispersity. It also possessed a high capacity for adsorption of a variety of inorganic particle and ionic species.