Preparation of B-doped TiO2 and degradation of toxic organic pollutants by visible light-catalysis

TiO2 nanoparticles doped with different content of boron was prepared by hydrothermal crystallization. The effect of synthesis conditions on the activity was researched by photo-degradation of organic pollutants under visible light. The results show that the best conditions of preparation is that the source of titanium is TiCl4, the basification is NH3·H2O, the amount of precursor powders is 65 g/L, the value of pH is 10, the best reaction temperature and time are 120C and 6 h respectively. The B/TiO2 nanoparticles was characterized by x-ray diffraction (XRD), transmission electron microscope (TEM) and UV-vis spectra. When the best mole rate of B and Ti was 0.04 measured by the photoelectron spectroscopy (XPS), the crystal form of B/TiO2 was mixed crystal with rutile phase and anatase phase, and the band gap of B/TiO2 was 2.7 eV. The photo-catalytic degradations of sulforhodamine B (SRB) and 2, 4 dichlorophenol (2, 4-DCP) under visible light were used probe reactions to evaluate photo-catalytic activities. Total organic carbon (TOC) in the degradation process of SRB had also been measured. It indicated that the mineralization rate of SRB was 42.4%.