Single Crystal Fe Nanowire Arrays Encapsulated by SiO2 Nanotubes
Single Crystal Fe Nanowire Arrays Encapsulated by SiO_2 Nanotubes

Aligned silicon dioxide nanotubes with diameter of 60～70 nm were synthesized inside the nanoholes of an anodic Al membrane (AAM) template by pressure impregnating the AAM pores with the SiO2 sol. The SiO2 nanotubes with different wall thickness were produced by repeating the process. Using the second-order template of porous AAM with silicon dioxide nanotubes, it was fabricated the nanostructure of Fe nanowires encapsulated by SiO2 nanotubes by electrochemical deposition. Scanning electron microscope (SEM) and transmission electron microscope (TEM) observations show that the nanotubes and nanocables are compact, continuous and uniform. Selected area electron diffraction (SAED) pattern shows the Fe nanowire is a single crystal. The magnetic properties of these samples were checked by a vibrating sample magnetometer (VSM). The coercivities of the samples are greatly improved compared to the corresponding bulk materials.