Template electrodeposition to cobalt-based alloys nanotube arrays

Parallel uniform arrays of amorphous ferromagnetic Co81Ni19 and Co37Fe63 alloy nanotubes with outer diameter around 325-365 nm, wall thickness of 30-60 nm and length of over 40 mu m were prepared by a direct current electrodeposition with mercury cathode using porous anodic aluminum oxide membrane as template. The morphology, structure, composition and magnetic property were studied. The results showed that mercury cathode is the key factor to form amorphous alloy nanotubes, and the as-prepared nanotube arrays exhibit obvious uniaxial magnetic anisotropy and the easy magnetization direction is perpendicular to the nanotubes axis. The mechanism of formation of Co based alloy nanotubes was also discussed. (C) 2008 Elsevier B.V. All rights reserved.