Tunable Magnetic Anisotropy Of Cobalt-based Magnetic Nanowire Arrays

Quasi-one-dimensional nanostructural materials have attracted an increasing interest due to their unique properties and potential applications in optics and electronics. Magnetic anisotropy is an important property of magnetic materials and determines their potential application values. The shape anisotropy and magnetocrystalline anisotropy dominate the total magnetic anisotropy of nanowire arrays, so the total magnetic anisotropy can be tuned by choosing proper magnetic materials, changing the shape anisotropy, such as preparing multilayer nanowires, and synthesizing magnetic composites, such as coaxial nanocables.Based on anodic aluminum oxide templates, cobalt nanowire arrays, Co/Cu multilayer nanowire arrays and Co/NiZn ferrite coaxial nanocable arrays can be synthesized by alternating current electrochemical deposition, direct current electrochemical deposition and a novel method combining an improved sol-gel template method and alternating current electrochemical deposition, respectively. The main conclusions are as follows:1. Co/Cu multilayer nanowire arrays have been synthesized by alternating current electrochemical deposition. The influence of the texture of HCP structured cobalt and the thickness of the magnetic layer and the nonmagnetic layer on the magnetic properties have been investigated.2. The texture of the HCP structural cobalt nanowires can be tuned by adding citric acid or sodium citrate. The texture can be changed from (002) texture to (101) texture, then to (100) texture with the increasing quantity of sodium citrate.3. Co/NiZn ferrite coaxial nanocable arrays have been synthesized via a novel method combining an improved sol-gel template method and alternating current electrochemical deposition for the first time. The influence of the thickness of the NiZn ferrite nanotubes on the magnetic properties has been investigated.