Preparation of Magnetic Fe3O4 Microspheres Using Different Surfactant and Silica-coated Magnetic Particles

Magnetic nanomaterials have received tremendous attention in the past years due to their unique magnetic responsiveness and corresponding wide applications in many fields.Herein this paper presents several methods to prepare monodisperse magnetic microspheres through a facile hydrothermal technique.The added surfactants were sodium dodecyl benzene sulfonate (SDBS), poly(vinylpyrrolidone) (PVP), trisodium citrate (TSC), and polyethylene glycol (PEG).Transmission electron microscopy (TEM) reveals the monodispersed magnetite (Fe 3 O 4 ) microspheres with narrow size distribution can be obtained using SDBS as the surfactant.In addition, Fe 3 O 4 @SiO 2 was prepared by modified Stöber methods resulting in the microspheres with more smooth surface and better dispersion.