Synthesis of core–shell Fe3O4@SiO2@MS (M = Pb, Zn, and Hg) microspheres and their application as photocatalysts

In this work, we report the fabrication of core–shell Fe3O4@SiO2@MS (M = Pb, Zn, and Hg) microspheres through a wet-chemical approach. The Fe3O4@SiO2@MS microspheres have both ferromagnetic and photocatalytic properties. The sulfide nanoparticles on the surfaces of microspheres can degrade organic dyes under the illumination of UV light. Furthermore, the microspheres are easily separated from the solution after the photocatalytic process due to the ferromagnetic Fe3O4 core. The photocatalysts can be recycled for further use with slightly lower photocatalytic efficiency.

► We prepared core–shell magnetic composite microspheres.
► These composites are multifunctional.
► They can serve as recyclable photocatalysts for wastewater treatment.