Effect of GO incorporation on microwave characteristics of Zn–Co ferrites nanocomposites

In the present work, we investigated the effect of graphene oxide (GO) concentration (wt. %=0.0, 2.5, 5, 7.5, 10) on microwave absorption properties of ZnxCo1−xFe2O4 ferrite (x = 0.0, 0.1, 0.2, 0.3) synthesized via hummer’s and ball milling method, respectively. The prepared nanoparticles were characterized to determine the structural, magnetic and electromagnetic properties. X-ray diffraction pattern of ferrites and nanocomposites matched well with the space group of cubic-phase. The saturation magnetization increases with Zn doping and decreases with the increase of GO concentration. Microwave absorption parameters were measured using Vector Network Analyzer in the range 12–18 GHz (Ku band). The complex permittivity and permeability were evaluated for different Zn doping and GO concentration. The reflection loss (RL) of −16.6 dB was obtained for Zn-0.3 and with incorporation of GO (wt. % = 7.5) in Zn-0.3, the RL value enhanced to −45.7 dB. The best RL value for Zn0.3-7.5GO resulted from best impedance matching (Z0/Zin). The incorporation of GO in spinel ferrites enhances the microwave absorption which make it as suitable composite for EMI shielding and flexible absorbing sheets.