Photocatalysis of methylene blue on titanium dioxide nanoparticles synthesized by modified sol-hydrothermal process of TiCl4.

Titanium dioxide nanoparticles were synthesized by the hydrolysis and condensation of TiCl4, an economic titanium precursor, in a mixed solvent of iso-propyl alcohol and water. As-prepared powders were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FE-SEM), energy filtering transmission electron microscopy (EF-TEM). To examine the photocatalytic activity of the as-prepared TiO2, the photodegradation of MB which is a typical dye resistant to biodegradation has been investigated on TiO2 powders in aqueous heterogeneous suspensions. The photocatalytic activity of TiO2 powders prepared by the hydrolysis of TiCl4 in the mixed solutions of iso-PrOH/H2O exceeded that of commercial TiO2 powders. The apparent first order rate constants ( k app) for the photodegradation of methylene blue (MB) showed a good correlation with the absorbance area obtained by UV-VIS DRS on wavelength in the limits of used lamp emission 300∼420 nm. [ABSTRACT FROM AUTHOR]