ROOM TEMPERATURE SELF-ASSEMBLY GROWTH OF COBALT NANOWIRES UNDER MAGNETIC FIELDS

Abstract

Polycrystalline cobalt nanowires, with average diameter of 80 nm and length about 10 μm, were synthesized in the hydrazine hydrate solution at room temperature under magnetic fields. A seed-mediated growth approach was applied. Magnetic fields induced the growth of nanowires via aligned self-assembly of cobalt nanocrystallites. Magnetic measurements showed that the saturation magnetization (Ms) of the cobalt nanowires synthesized under magnetic field was five times larger than that of the samples prepared without magnetic fields; while the coercivity (Hc) of the sample prepared under magnetic fields was half of that of the sample synthesized without magnetic fields. The reasons for the magnetism changes were discussed.