Arrays of α-Fe2O3 nanowires embedded in anodic alumina membranes were obtained after heat-treating β-FeOOH nanowire arrays fabricated by electrochemical deposition. Haematite polycrystalline nanowires with maximum length of about 7μm and average diameter of about 120nm were characterized by means of x-ray diffraction and transmission electron microscopy. The Morin temperature below 80 K and N´eel temperature of about 350K for the α-Fe2O3 nanowire arrays, far lower than those of bulk material, were measured by Mössbauer spectroscopy and using a Magnetic Property Measurement System.

Detailed fabrication, structure, and magnetic properties of Fe1-xNix nanowire arrays were investigated. The dependence of structural variation on the Ni content was determined by x-ray diffraction, showing different behaviors of nanowire arrays from the bulk and particle systems. The magnetic properties in the temperature range of 5 to 300 K were studied and results show the coercivity at 300 K does not monotonically decrease as Ni content increases. When the applied field is along the long axis, the temperature dependence of coercivity for Fe0.68Ni0.32 and Fe0.19Ni0.81 nanowire arrays shows a linear decreasing with increasing temperature, which can be understood by a phenomenological nucleate model.