Preparation of DyVO4 by Sol-Gel Method and Research of Its Photocatalytic Activity

Using dysprosium oxide (Dy2O3), ammonium metavanadate (NH4VO3), nitric acid (HNO3) and citric acid (C6H8O7·H2O) as main raw materials, DyVO4 was successfully prepared by sol-gel method. DyVO4 samples were characterized by thermogravimetry differential scanning calorimetry (TG-DSC), X-ray diffraction (XRD), scanning electron microscope (SEM), diffuse reflectance spectrum (DRS) and Fourier transform infrared spectroscopy (FT-IR). Under condition of ultraviolet light, taking 10 mg/L methyl orange solution as simulated sewage, the effects of synthesis temperature and illumination time on the photocatalytic activity of DyVO4 were studied. The results show that pure tetragonal zircon DyVO4 samples can be obtained under calcination conditions of 600 °C to 900 °C. The average grain size is about 2 μm and the breadth of band gap is about 3.52 eV. The sample prepared at 800 °C has the best photocatalytic activity. Under ultraviolet light illumination for 150 min, the degradation rate of 10 mg/L methyl orange can reach nearly 100% in presence DyVO4. DyVO4 prepared by sol-gel method is a photocatalyst which has broad application prospect.