Preparation And Characterization Of Magnetite Micro-powders

In this paper, using the soluble ferrous chloride as iron sources, uniform magnetite octahedrons with different sizes have been successfully synthesized by the means of mixed solvothermal method in the mixture of ethylene glycol and hydrazine hydrate. The chemical compositions, morphologies were characterized by XRD, EDS, SEM measurements and magnetic measurement was conducted by Vibrating Sample Magnetometer (VSM). The effect of experimental factors such as the volume ratio of two different solvents , reaction temperature and surfactant to the products were discussed. It is essential using mixed solvent for obtaining magnetite octahedrons with pure phase and uniform morphology. While the volume ratio of hydrazine hydrate to ethylene glycol was changed in some range, magnetite octahedrons with different size were obtained. Such experimental factors as reaction temperature, also played crucial role for formation of magnetite octahedron. While some amount of surfactant was added, instead of octahedron, magnetite cubic microcrystal was obtained. Magnetic measurements showed that The as-synthesized sample possessed saturation magnetization and coercive field that close to and much lower than that of the bulk respectively. There was no evident dependence between the magnetic properties of different size magnetite octahedrons and their particle size.