Fabrication and magnetic properties of ordered 20 nm Co–Pb nanowire arrays

Ordered Co–Pb nanowire arrays embedded in anodic alumina template were successfully fabricated by electrodeposition. Transmission electron microscopy (TEM) and X-ray diffraction (XRD) observations revealed that the Co–Pb nanowires were polycrystalline with uniform diameters around 20 nm and lengths up to several micrometers. Magnetic measurements showed that the coercivity and remanence of the as-deposited Co–Pb nanowires decreased with the increase of the Pb content. After annealing the Co–Pb nanowires present higher coercivities (2.4–2.5 kOe) than that of pure Co nanowires (2.1 kOe) and the dependence of coercivity and remanence on the Pb content is inconspicuous. A phase separation of Co and Pb occurred after annealing. The familiar pinning model was employed to explain the above experimental results.