Synthesis, characterization and microwave absorbing properties of the novel ferrite nanocomposites

In this study, the synthesis of magnetic nanocomposites with the special stoichiometries of Ba0.34Sr0.34Cd0.16Zn0.16Fe12O19 (S1) and Ba0.69Sr0.17Cd0.07Zn0.07Fe12O19 (S2), having microwave absorbing properties were successfully carried out and reported. These nanoparticles were synthesized using self-assembly reflux reaction followed by heating treatment. The scanning electron microscopy (SEM) images depicted the uniform morphology of particles with the average sizes of 43 and 38 nm for the samples (S1) and (S2), respectively. The saturation magnetizations of 65.09 and 66.59 emu/g were analyzed using a VSM technique at room temperature for these uniform nanoparticles. The X-ray diffraction (XRD) patterns revealed that the matrices of both produced samples have been made from M-type hexagonal structure. The microwave absorbing characteristics were investigated via measuring the absorption of electromagnetic waves by these products with various thicknesses in the frequency range of 8-12 GHz (X-band). These nanocomposites revealed the enhanced reflection loss (R. L.) properties due to calcination process at different temperatures and improvement of the crystalline structures. The reflection losses of -35 and -23 dB were simply obtained for the resulting (S1) and (S2) nanocomposites with the optimum thickness of 2.1 mm. These results suggest that the synthesized magnetic composites can be employed as effective microwave absorbers in various devices. (C) 2012 Elsevier B. V. All rights reserved.