Synthesis and characterization of monodisperse iron oxides microspheres

Monodisperse alpha-Fe2O3 microspheres of different shapes have been selectively synthesized through the hydrothermal process. The products were characterized by powder X-ray diffraction and scanning electron microscopy. All the alpha-Fe2O3 microspheres have good dispersibility, uniform size, and well-defined shapes. The ferromagnetic investigation of the egg-like alpha-Fe2O3 microspheres gave extremely high coercivity of 3800 Oe at room temperature. The formation mechanism of these microspheres was preliminarily discussed. Nanorods and branched nanorods of a hydroxide precursor Fe8O8(OH)(8)Cl-1.35 have been captured. Monodisperse Fe2O3 microspheres have also been prepared, and their magnetization saturation value is about 40.1 emu/g.