Synthesis of Magnetic Particles and Silica Coated Core-Shell Materials

Abstract

Ferrite particles were prepared by hydrothermal process at high temperature. The characterization of ferrite was examined by XRD, Mössbauer spectrum, and SEM. The XRD and Mössbauer spectrum confirmed that ferrite particles have a Fe 3 O 4 inverse spinel structure, the SEM results show that each Fe 3 O 4 particles were composed of many smaller magnetite nanoparticles. The as-synthesized Fe 3 O 4 particles were modified by sodium citrate then further coated with SiO2 layer through the modified stöber method. The composited Fe 3 O 4 @SiO 2 microspheres exhibited outstanding monodispersity and magnetic property.