Core-shell CoFe۲O۴-ZnO nanocomposite for electromagnetic wave absorption application

The rapid development of electromagnetic communication and electronic technology has led to significant challenges related to electromagnetic interference (EMI) and radiation. Electromagnetic waves pose serious threats to military safety, high-frequency electronic components, and precision instruments, underscoring the urgent need for the development of electromagnetic wave (EMW) absorbing materials for protection. In this study, a co-precipitation method was employed to synthesize a core-shell structure of cobalt ferrite@zinc oxide (CoFe۲O۴@ZnO) nanocomposite. The structural, morphological and electromagnetic wave absorption properties of the synthesized nanocomposites were characterized using X-ray diffraction (XRD), vibrating sample magnetometry (VSM), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and vector network analysis (VNA). The performance of the prepared nanocomposites for microwave absorption in the X-band range was investigated through the transmission line method via an X-band waveguide to measure EM parameters of the nanocomposites. To evaluate the electromagnetic wave absorption properties, two parameters‒ sample thickness and core-to-shell ratio content‒ were selected. The results indicated that the electromagnetic wave absorption performance of the nanocomposite was optimal at a CoFe۲O۴:ZnO of ۲:۱ and sample thickness of ۱ mm, achieving a maximum of reflection loss of −۱۱ dB and alongside a broad effective bandwidth across the entire X-band. This performance is attributed to the synergistic effects of dielectric magnetic losses between CoFe۲O۴ and ZnO, enhanced interface polarization, improved reflection, and scattering pathways of electromagnetic waves within the core-shell nanocomposite.

کلیدواژه ها:

Electromagnetic wave absorption ، Cobalt ferrite ، Reflection loss ، Core-shell ، Nanocomposit