Surfactant assisted synthesis and multifunctional features of Fe_3O_4@ZnO@SiO_2 core-shell nanostructure

摘要

In this study, hybrid core-shell magnetic nanostructure comprising Fe_3O_4 core with multiple shells of zinc oxide and silica having well defined morphologies are produced by a simple synthetic approach based on an effective chemical precipitation technique. Semi-solid and hydro-philic poly ethylene glycol was used as the stabilizing agent to control the particle size of the magnetic nanostructures. 1-Hexadecyltrimethyl ammonium chloride was employed as the surfactant to achieve the core-shell nanostructure. The formation of the core-shell nanostructures were confirmed by X-ray diffraction, Fourier transform infra-red spectroscopy and high resolution transmission electron microscopy respectively. We also observed the pronounced ferromagnetic features of ZnO coated Fe_3O_4 core-shell nanostructure that substantiates the magnetization reversal mechanism of the spinel magnetite. The coating of dense SiO_2 on Fe_3O_4@ZnO was found to shift the magnetic behaviour from ferromagnetic to super-paramagnetic even at room temperature. The optical features of the material are observed by UV-Vis Spectrometer and Photoluminescence spectrometer.