Correlation of Surface Properties and Photocatalytic Activity of Nanocrystalline TiO₂ on the Synthesis Route

Present work describes the synthesis of nanocrystalline TiO₂ photocatalyst using sol-gel and solution combustion methods and their characterisation by powder X-ray Diffraction, Diffuse Reflectance Spectroscopy, surface area measurement, FT-IR, FT-Raman, Thermo Gravimetric Analysis, and Transmission Electron Microscopy. Their photocatalytic activity was evaluated by the degradation of two nitro aromatic pollutants, viz. para-nitroaniline (PNA) & meta-dinitrobenzoic acid (DNBA) commonly observed in nitroaromatic plants. Performance of the synthesized catalysts was compared with commercial Degussa P25 sample. The photocatalytic degradation and total mineralization were monitored using UV/VIS spectrophotometer and total organic carbon content analysis respectively. The materials properties such as crystallinity and surface hydroxyl group on the nanocrystalline TiO₂ played crucial role for the total mineralization of the nitroaromatics.