Manipulation of carbon nanotube magnetism with metal-rich iron nanoparticles

Abstract

Metallic Fe nanoparticles (NPs) were electrodeposited onto ozone functionalized carbon nanotubes (CNTs) to produce ferromagnetic carbon nanomaterials. Chemical and structural characterisation of these nanomaterials as a function of iron deposition time was undertaken and related to their magnetic properties. Density functional theory calculations of the Fe and CNT system were also undertaken and showed that in the initial stages of electroplating CNT oxygen sites were favoured. At short deposition times, individual NPs were observed. As electrodeposition continues, individual crystalline NPs began to overlap and fine grain films were formed. It is evident that the plating conditions influence iron crystallinity and oxygen levels, producing Fe–CNT materials with wide ranging coercivity.