Photocatalytic degradation of MO by complex nanometer particles WO_3/TiO_2

摘要

Complex nanometer particles WO_3/TiO_2 were prepared using a sol-gel process and characterized using XRD spectra. The photocatalytic activity of TiO_2 can be increased by doping W~(6+) with TiO_2 because the doped W~(6+) that entered into the crystal lattices of TiO_2 led to the formation of defects in the crystal lattices of TiO_2 and thereby improved the photocatalytic activity of TiO_2.When WO_3 doped in TiO_2 exceeded 3%, the excess W~(6+) did not enter into the crystal lattices of TiO_2 but were uniformly dispersed in TiO_2 or they covered the surface of TiO_2, which reduced the effective illumination area of TiO_2 and thereby lowered the photocatalytic activity of TiO_2.The relationship among the composition of the catalyst, the amount of photocatalyst, the illumination time, and the decolorizing rate of methyl orange (MO) were discussed. The results show that the decolorizing rate of MO can reach 82.3% using WO_3/TiO_2 as the photocatalyst, with the composition of WO_3/TiO_2 =3:97, the mass of catalyst = 0.400 g, the initial concentration of MO = 20 mg/L, pH = 6.5, and the illumination time = 7 h.