SiC–Fe3O4dielectric–magnetic hybrid nanowires: controllable fabrication, characterization and electromagnetic wave absorption

Controllable dielectric–magnetic coaxial hybrid nanowires, having a core of SiC nanowires and a shell of Fe3O4 nanoparticles, have been synthesized using a straightforward polyol approach. The morphology, microstructure and magnetic properties of the SiC–Fe3O4 hybrid nanowires have been characterized by transmission electron microscope, powder X-ray diffractometer and vibrating sample magnetometer. The characterization confirms that monodisperse Fe3O4 nanoparticles of core size 10 nm have been successfully coated on the surface of SiC nanowires. The coverage density of the nanoparticles may be adjusted simply by changing the weight ratio of the precursors. Measurement of the electromagnetic (EM) parameters indicates that the Fe3O4 nanoparticles increase the magnetic loss and improve the impedance matching conditions compared to untreated SiC nanowires. When the coverage density of Fe3O4 is optimal, the reflection loss of an EM wave can be as low as −51 dB. By changing the loading density of Fe3O4, the best microwave absorption state was obtained in the 2–18 GHz band. These results suggest that SiC–Fe3O4 hybrid nanowires will be valuable in EM absorption applications.