Indium-sensitized UV Photocatalysts made from Alkali Titanate Microfibers

摘要

Indium-alkali microfibers doped ceramic were prepared by the sol-gel process. The gels preparation samples, were heat treated at 700°C for different length of time. The products were characterized by means of XRD, SEM-EDS and UV-Vis-DRS. The XRD showed the formation of the Na_2Ti_6O_(13) phase whose crystallinity depends on the annealing time. The band gap calculated from the UV-Vis Kubelka-Munk function shows very similar values (3.53-3.55 eV). The SEM images of the indium-alkali titanates show microfiber clumps morphologies of about 5 μm, and the EDS spectra show that In_2O_3 is on the Na_2Ti_6O_(13) surface. The results of the evaluation of the In-Na_2Ti_6O_(13) semiconductors in the 2, 4-dichlorophenoxyacetic acid (2, 4-D) photodecomposition under UV light irradiation, show that the photoactivity depends on the time of heat treatment of the samples.