(FexCo1-x)-alloy filled vertically aligned carbon nanotubes grown by thermal chemical vapor deposition

Aligned Fe-Co alloy filled multi-walled carbon nanotubes (MWNTs) were synthesized on silicon substrates via the pyrolysis of a ferrocene/cobaltocene mixture. The nanotubes are aligned normal to the substrate surface. The encapsulated metal nanowires have diameters of 10-20 nm and a length of up to a few micrometers. They consist of single crystals with BCC structure. Alternating gradient magnetometry investigations show that the magnetic wires exhibit a clear ferromagnetic behavior at room temperature. An enhanced coercivity of about 126mT and uniaxial magnetic anisotropy with the easy axis of magnetization along the wire axis were observed. (c) 2004 Elsevier B.V. All rights reserved.