Preparation of Magnetic Composite Photocatalyst Fe3O4/SiO2/Bi2WO6 and Its Photocatalytic Activity

The magnetically recoverable photocatalyst Fe3O4/SiO2/Bi2WO6 was synthesized by a three-step approach. After a hydrothermal process of preparing ferroferric oxide (Fe3O4), these Fe3O4 nanoparticles were coated with SiO2 by a sol-gel method. Finally, Fe3O4/SiO2 nanoparticles were immobilized onto the surface of Bi2WO6 by a second hydrothermal process. The morphology, structure and properties of the composite were characterized by XRD, SEM, PL spectra and UV-vis absorption spectrum. The results show that the Bi2WO6 nanosheet structures with an average diameter of 500 nm are further decorated by Fe3O4 nanoparticles with an average diameter of 500 nm. The photocatalytic activity of Fe3O4/SiO2/Bi2WO6 to degrade rhodamine B is close to that of pure Bi2WO6. The photocatalyst with appropriate superparamagnetism can be easily re-collected by applying an external magnetic field. It shows potential applications in pollutant degradation. © 2018, Science Press. All right reserved.