Photodegradation of Methyl Orange in Water on Ho~(3+)-doped TiO_2 Nanoparticles under Ultraviolet Light Irradiation

摘要

The un-doped and Ho~(3+)-doped TiO_2 nanoparticles were prepared by sol-gel method with Ti (OC_4H_9)_4 as raw materials and characterized with X-ray diffraction (XRD) and UV-Vis absorption spectra, and their photocatalytic activities were investigated by photocatalytic oxidation of methyl orange in water. It is found that the Ho doping reduces crystallite size, and expands crystal matrix of TiO_2, which helps to improving the photocatalytic activity of TiO_2. In the experiment condition, the optimum Ho~(3+) concentration is about 0.3%. And a tiny blue-shift of the absorption profile and two absorption peaks about at 450 and 540 nm respectively were found in Ho~(3+)-doped TiO_2.