Highly stable Fe–Ni alloy nanoparticles encapsulated in carbon nanotubes: Synthesis, structure and magnetic properties

Highly stable Fe–Ni alloy nanoparticles encapsulated in carbon nanotubes have been synthesized by in situ catalytic decomposition of benzene over Fe–Ni alloy nanoparticles generated through procedures of sol–gel fabrication and hydrogen reduction. The phases of graphite and γ-FeNi solid solution (face centered cubic) were identified by X-ray diffraction. The results of FE-SEM and HRTEM characterization revealed that Fe–Ni nanoparticles encapsulated in carbon nanotubes are generated in large quantity. The composites are highly stable in air and show soft magnetic property, with saturation magnetization affected by the composition of Fe–Ni alloy and the temperature of benzene decomposition.