Synthesis of core/shell/shell Fe3O4/SiO2/ZnO nanostructure composite material with cubic magnetic cores and study of the photo-degradation ability of methylene blue

Abstract

The Fe3O4/SiO2/ZnO cubes were synthesized with core/shell/shell nanostructure through layer-by-layer chemical technique. At first, the Fe3O4 cubic powder was synthesized by the carbon reduction method. In the next step, the SiO2 shell was produced on Fe3O4 cube particles. Then a layer of ZnO was coated using zinc nitrate hexa-hydrate precursor by co-precipitation route. The Fe3O4/SiO2/ZnO cubes were characterized by XRD, FESEM fitted with EDX, FT-IR, and TEM. Magnetic properties of the prepared composite were studied by VSM. The results indicated that magnetite particles have been successfully coated. The saturation magnetization of the prepared Fe3O4 powder and Fe3O4/SiO2 and Fe3O4/SiO2/ZnO composites were 80, 66, and 48.8 emu/g, respectively. The results showed that the change in surface to volume ratio was effective in photo-catalyst properties of cubes. Also, the synthesized composite showed good photo-degradation ability on the removal of methylene blue (MB). The photo-degradation of methylene blue dye was about 55% in the presence of Fe3O4/SiO2/ZnO cubes under UV irradiation time of 90 min. Four consecutive cycles of MB dye degradation were obtained using Fe3O4/SiO2/ZnO composites. Fe3O4/SiO2/ZnO composite could be recovered using a strong magnetic field and the photo-catalyst particles could be re-used.