Preparation of GdCoO3 by Sol-Gel Method and Its Photocatalytic Activity

Using gadolinium nitrate, cobalt acetate, citric acid as main raw materials, GdCoO3 was successfully prepared by sol-gel method. The prepared samples were characterized by thermogravimetric differential scanning analysis (TG-DSC), X-ray diffraction analysis (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy(FT-IR). Using methyl orange solution as simulated sewage, it was investigated that the effects of synthesis temperature and illumination time on photocatalytic activity of GdCoO3. The results show that the pure cubic perovskite GdCoO3 samples can be prepared at calcination temperature of 700 °C to 1000 °C. The GdCoO3 calcined at 900 °C has uniform particles and an average grain size of about 0.5 μm to 1 μm. The photocatalytic performance of GdCoO3 calcined at 900 °C sample was the best. Under the condition of UV-light for 120 min, the photocatalytic degradation rate of methyl orange reached more than 96% in presence GdCoO3 calcined at 900 °C. This indicates that GdCoO3 has good photocatalytic performance.