A time-saving method to prepare monodisperse Fe₃0₄ microspheres with controllable sizes and morphologies

Monodisperse Fe₃O₄ microspheres with tunable diameters and high magnetic saturation were synthesized by a solvothermal reduction method. It was found that the morphology and structure of the Fe₃O₄ microspheres could be tuned by simply altering the amount of the reactants such as ferric chloride, sodium acetate, water, and the reaction time. The Fe₃0₄ microspheres obtained via this method possessed high purity, crystallinity, and a nearly spherical shape. Furthermore, they were monodispersed and no aggregation was found. Such monodisperse Fe₃O₄ microspheres had tunable diameters of 400-700 nm and the fabrication time was only 2-4 h. The products showed high magnetic saturation values, and their yields were typically more than 94%.