Electromagnetic and microwave absorbing properties of Ni 0.5Zn 0.5Fe 2O 4/bamboo charcoal core–shell nanocomposites

Abstract

Bamboo charcoal coated with nanoparticles Ni 0.5Zn 0.5Fe 2O 4 spinel ferrite, forming a core–shell structure, were synthesized by utilizing hydrothermal method at different bamboo charcoal content (10, 20 and 30 wt%) and introduced into epoxy resin to be a microwave absorber. Structural characterization by Fourier transform infrared, X-ray diffraction, scanning electron microscopy and transmission electron microscopy proved that nanometer-sized Ni 0.5Zn 0.5Fe 2O 4 in the composites was responsible for the ferromagnetic behavior of the composites. The electromagnetic properties of the Ni 0.5Zn 0.5Fe 2 O 4/bamboo charcoal composites exhibited super-paramagnetic behavior and low blocking temperatures. The reflection loss of composites measured in the microwave frequency range of 2–18 and 18–40 GHz showed that microwave absorbing properties of the Ni 0.5Zn 0.5Fe 2O 4/bamboo charcoal composite were higher than that of Ni 0.5Zn 0.5Fe 2O 4 and bamboo charcoal.