Photocatalytic activity of sol-gel derived titania converted into nanocrystalline powders by supercritical drying

Nanocrystalline (14-18 nm) anatase TiO2 powders with high photocatalytic activity are synthesized by a sol-gel method followed by supercritical drying in isopropanol. The photocatalytic behavior is studied in the model reaction of phenol photodegradation in water. The relationship between photoactivity, crystal structure, texture, charge-carrier lifetimes, bandgap energies and thermal treatment of products is discussed. The effective method of synthesis of photocatalysts based on TiO2-sol-gel method followed by supercritical drying in isopropanol is presented. It shows, that the obtained powders can be used in photocatalytical depollution without additional thermal treatment.