Title :
Fe-Co and Fe-Ni Nanocluster Wires by Hydrogen Reduction in Nanoporous Alumina Templates
Author :
Cui, B.Z. ; Gonzales, Brian ; Marinescu, Mariana ; Liu, J.F.
Author_Institution :
Electron Energy Corp., Landisville, PA, USA
Abstract :
This paper reports the fabrication, formation mechanism, nanostructure and magnetic properties of Fe50Co50, Fe65Co35 and Fe50Ni50 (at.%) nanocluster wires (NCWs) with different aspect ratios fabricated by thermal decomposition of metal nitrates and subsequent hydrogen reduction in nanoporous anodized aluminum oxide (AAO) templates. The as-synthesized NCWs have diameters in the range of 80-360 nm, and lengths in the range of 0.5-10 μm. The NCWs are composed of roughly round-shaped nanoclusters in the range of about 5-50 nm in size and a weighted average size of 14 nm with a mixture of single-crystal and poly-crystalline structures. The Fe-Co NCWs have a bcc structure while the Fe50Ni50 NCWs have an fcc structure. An intrinsic coercivity at room temperature iHc of 1.15 kOe was obtained for the Fe65Co35 NCWs. The NCWs exhibit the easy magnetization direction along the length of the nanowires as a result of the shape anisotropy.
Keywords :
cobalt alloys; coercive force; iron alloys; magnetic anisotropy; mixtures; nanofabrication; nanomagnetics; nanoporous materials; nanowires; nickel alloys; pyrolysis; AAO templates; FeCo; FeNi; bcc structure; fcc structure; hydrogen reduction; intrinsic coercivity; magnetic properties; magnetization direction; metal nitrates; nanoporous alumina templates; nanoporous anodized aluminum oxide templates; nanostructure fabrication; nanowire length; poly-crystalline structures; roughly round-shaped nanoclusters; shape anisotropy; single-crystal mixture; size 80 nm to 360 nm; temperature 293 K to 298 K; thermal decomposition; Anisotropic magnetoresistance; Hydrogen; Iron; Nanowires; Nickel; Wires; Coercivity; Fe-Co and Fe-Ni nanocluster wires; hydrogen reduction; magnetic shape anisotropy; thermal decomposition;
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2013.2247575