Structure and magnetic properties of Co nanowires in self-assembled arrays

Co nanowire arrays have been electrodeposited into self-assembled anodic aluminium oxide templates. It is found that the crystal structure of the Co nanowires depends on the pH value of the deposition electrolyte. The XRD results show that Co nanowires are fcc structure at pH = 2.7, a mixture of structures of fcc and hcp at pH = 3.5, and hcp structure at pH = 5.0. The effective anisotropy along the nanowire axis of the fcc Co nanowire array is obviously stronger than that of the hcp Co nanowire array, and the coercivity of the fcc structure is also larger than that of the hcp structure when they are the same diameter.