TIO2 AEROGELS FOR PHOTOCATALYTIC DECONTAMINATION OF AQUATIC ENVIRONMENTS

We describe synthesis and applications of nonsupported semiconducting porous structures that can be used as photocatalysts for photodegradation of organic pollutants in aqueous environments. The photocatalysts, TiO2 aerogels, are prepared through the sol-gel method and supercritical point drying. These materials have a porosity of 85%, a BET surface area of 600 m2/g, and a bulk density of 0.5 g/cm3. X-ray diffraction show the anatase crystalline phase with a crystallite size of 50 angstrom. The surface area, pore volume, and pore size distribution of these materials depend on the preparation conditions. The photoassisted oxidation of salicylic acid on these materials was compared to that obtained with commercial (P-25) TiO2 powder. The aerogel shows a much higher photocatalytic activity.