Structure and magnetic properties of metastable Co–Cu solid solution nanowire arrays fabricated by electrodeposition

Nanowire arrays of the metastable Cox Cu1–x (0.20 ≤ x ≤ 0.85) solid solution system which can not be obtained by equilibrium methods, were prepared by electrodeposition in pores of anodic aluminum oxide (AAO) template, and subsequently annealed at different temperatures. The as‐deposited samples all show single phase of fcc structure, and lattice parameters decrease with the increase of Co content and fundamentally accord with Vegard's law. The phase transition with heat treatment was investigated by X‐ray diffraction and differential thermal analysis (DTA) which further confirmed the formation of solid solution. With Co content increasing, the coercivity along nanowire axis for as‐deposited samples increases, but it decreases for the annealed samples at 700 °C. This phenomenon was explained considering the interaction of Co particles through Cu in nanowires after phase separation. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)