Preparation of SrTi0.1Fe0.9O3−δ and its photocatalysis activity for degradation of methyl orange in water

Magnetic perovskite-type SrTi0.1Fe0.9O3−δ was synthesized by stearic acid gel combustion method. The obtained powders were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR), vibrating sample magnetometer (VSM) and UV-Visible absorption spectrum techniques. Mean valence of Fe ion and the concentration of oxygen vacancies in SrTi0.1Fe0.9O3−δ were measured by iodometric method. The magnetic properties of the SrTi0.1Fe0.9O3−δ were measured, and the SrTi0.1Fe0.9O3−δ was also evaluated for its photocatalytic activity towards the degradation of methyl orange (MO) under the sunlight irradiation. The experimental results show that the SrTi0.1Fe0.9O3−δ is the photocatalyst possessing of magnetic property and visible-light activity, i.e., bifunctional photocatalyst. The SrTi0.1Fe0.9O3−δ is applicable to the magnetic separation process and also shows excellent photocatalytic activity for the degradation of MO. The optimal conditions for photocatalytic degradation were methyl orange concentration of 20 mg L−1 at pH 6.0 with the SrTi0.1Fe0.9O3−δ concentration of 7.29 mg L−1 for 3 h. In addition, the SrTi0.1Fe0.9O3 is reusable and maintain relatively high activity. This study could point out a potential way to develop new and more active magnetic perovskite-type photocatalysts.