Comparison of Physicochemical Properties of Three Nanostructure Composite TiO<SUB>2</SUB> Films and Their Photocatalytic Properties

Abstract

Three type of photocatalytic composite films, MPC500SGF-MC, ANPSGF-MC and P25SGF-MC, have been synthesized by a modified sol-gel method using different particle size of TiO2 nanopowder MPC500, ANP and P25, respectively. Methyl cellulose (MC) was added as a template to the sol for stress reduction which improved not only the amount of crystalline material immobilized on the support, but also the nanosize of the films calcined at 500 degrees C. The physicochemical properties, including surface morphology, crystallinity, crystal size and adhesion on glass substrate, of the three types of films were investigated by SEM, XRD and the scratch test. The photocatalytic activities of the films were compared using methyl orange (MO) as a model organic contaminant in water. The results on photocatalytic degradation of MO showed that the increase in photocatalytic activity for P25SGF-MC, compared with that of MPC500SGF-MC and ANPSGF-MC composite films. The optimum degradation conditions of MO solution are determined. This study proves that particle size of starting TiO2 material is important for the preparation of nanostructured TiO2 composite film with enhanced photocatalytic activity and excellent adhesion on the glass substrate.