Decoration of multi-walled carbon nanotubes with Fe_xNi_1-xalloys and their magnetic properties

Multi-walled carbon nanotubes (MWCNTs) decorated with an Fe-Ni alloy using a wet impregnation process, and their magnetic properties are investigated. The composition ratio of the Fe_xNi_1-xalloy particles attached to the MWCNTs surface is controlled by the amount of each metal added during the manufacture of the mixed solution. The saturation magnetization (Ms) and the ratio of saturation magnetization to remanent magnetization (Ms/Mr) are influenced by the Ni and Fe concentrations in the metal alloy. The Fe_xNi_1-x/MWCNTs samples show a transition to soft magnetic materials with increasing Ni content in the metal alloy, and the transition tends to improve as the amount of metal content is increased, showing an increase in Ms and the Ms/Mr ratio. The differences in the magnetic properties between the metal alloys attached to and detached from the MWCNTs are discussed.