Enhanced Photocatalytic Activity of Sol-Gel Derived Coral-like TiO2 Nanostructured Thin Film

Abstract

To enhance photocatalytic degradation of organic pollutants, coral-like TiO2 nanostructured thin films were chemically synthesized through the sol-gel method. The fabricated thin films were characterized by Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD), nitrogen sorption isotherms, mercury porosimetry measurements, and UV-Vis Diffuse Reflectance Spectrum (DRS). The coral-like TiO2 structures were assembled from cashew-like nanoparticles, which were composed of numerous highly crystallized in anatase phase. The assembled materials possess a high specific surface area of 167 m2/g and mean pore size diameter of 12.3 nm. The coral-like TiO2 nanostructured thin film shows a significantly higher photocatalytic activity than that of the commercial photocatalyst P25-TiO2 based film on the degradation of Methylene Blue (MB) and Methyl Orange (MO). The high photocatalytic activity of film was ascribed to the large light absorption caused by small particle size, micro/meso, and macropore structures, and pore scattering, reduced band gap energy, and reduced recombination of electron-hole pairs. These findings open up a new approach for promising environmental applications.