The synthesis of Fe3O4@SiO2 superparamagnetic materials and mechanism of catalysis

Abstract

Abstract The superparamagnetic Fe3O4 was fabricated by the solvothermal synthesis, in which medium ferric chloride is the iron source and deoxidizer using as ethylene glycol. The core-shell material Fe3O4@SiO2 was fabricated by the scheme which was composed of Anhydrous ethanol, deionized water, ammonia water, and tetraethyl orthosilicate (TEOS). The structural and optical characteristics of the samples Fe3O4 and core-shell Fe3O4@SiO2 was detected by X-ray diffraction (XRD), transmission electron microscope (TEM), Vibrating sample magnetometer (VSM), and UV/VIS/IR spectrophotometer. The conclusions illustrate that the spherical core-shell structure of Fe3O4 and Fe3O4@SiO2 were fabricated with superparamagnetic. The Ostwald ripening effect on structure of sample Fe3O4 was concluded to form inverse spinel polycrystal structure by nanometer particles. The visual-driven photocatalytic properties of Fe3O4 and Fe3O4@SiO2 nanoparticles toward the deposition of methodology blue was studied. The obtained conclusions indicate that Fe3O4@SiO2 after irradiated by visible light, its degradation rate of methodology methylene mlue (MB) was enhanced than Fe3O4 in the presence of H2O2. The samples Fe3O4 and core-shell Fe3O4@SiO2 materials are recycled by external magnetic field and reused for special superparamagnetic property. The sample Fe3O4 and core-shell Fe3O4@SiO2 materials represent higher catalytic property and excellent fixity consistent with the decomposition rate of methodology methylene mlue (MB) after being recycling and reuse severe times. The photocatalytic mechanism was dismissed based on the determined active agent during the process of degraded wastewater.