Hollow magnetite spheres: Synthesis, characterization, and magnetic properties

Magnetite (Fe3O4) hollow spheres have been synthesized in ethylene glycol (EG) solution without adding any additives, using FeCl3 · 6H2O and urea as the starting materials. The experimental results reveal that the solvent and reaction temperature have the important influences on the phase and morphology of the products based on XRD and TEM characterization. The magnetic properties of magnetite hollow spheres exhibit a ferromagnetic behavior according to the magnetic hysteresis curve measured at room temperature. It is noticeable that β-FeOOH nanorods and α-Fe2O3 nanocrystallites can be selectively fabricated by adjusting the reaction solvents.