Template-free synthesis and characterization of novel 3D urchin-like alpha-Fe2O3 superstructures

Novel three-dimensional (3D) urchin-like alpha-Fe2O3 superstructures were successfully prepared by a template-free hydrothermal synthetic route using FeSO4 center dot 7H(2)O and NaClO3 as reagents. The as-obtained products were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Brunauer-Emmett-Teller analysis and vibrating sample magnetometry. It is shown that the superstructures consisted of well-aligned alpha-Fe2O3 nanorods growing radially from the cores of the superstructures. The alpha-Fe2O3 nanorods have an average length of about 800 nm and a mean diameter of about 80 nm. Magnetic hysteresis measurement reveal that the urchin-like alpha-Fe2O3 superstructures display weak ferromagnetic behavior with a remanence of 4.6783x10(-3) emu g(-1) and a coercivity of 92.235 Oe at room temperature. The formation mechanism of the 3D urchin-like alpha-Fe2O3 superstructures was also discussed.