Ordered arrays of nickel nanowires covered by polystyrene nanotubes have been synthesized for the first time by combined electrochemical and chemical routes into anodic alumina templates. The achieved long-range hexagonal ordering of nanowire-nanotube composite mimics that of the precursor anodic alumina oxide template. The resulting cylindrical composite, 25 μm in length, consists of a polymer nanotube shell of 280 nm outer diameter filled with a metallic magnetic nanowire core of 140 nm diameter. The magnetic characterization of the nanowire-nanotube composite array indicates the presence of an effective magnetization easy axis parallel to the nanowires, ascribed mostly to the shape anisotropy of Ni nanowires. Moreover, individual composite nanowires can be chemically released from the membrane which opens a new line of technological development in which single composite nanowires profit from their polymeric functionalization while being simultaneously oriented/displaced under suitable magnetic field.

Financial support from the Spanish Ministerio de Economia y Competitividad under Projects MAT2011-24797 and MAT2014-53437-C2-1 at ICTP/CSIC is acknowledged. Research at ICMM/CSIC was supported by the Spanish National Research Council under Project 201460E014 and the Regional Government of Madrid under Project S2013/MIT- 2850 NANOFRONTMAG-CM.

Peer Reviewed