Enhancement of microwaves absorption properties of CuFe₂O₄magnetic nanoparticles embedded in MgO matrix

The nanocomposites of MgO/CuFe₂O₄has been prepared by two steps co-precipitation method at low temperature. The crystal structure, morphology and particle size have been characterized by X-ray Diffraction (XRD) and Transmission electron microscopy (TEM). The average crystallite size lies in the range of 20–32 nm and XRD pattern also confirms the coexistent of both phases without impurity related phases. The TEM images reveal that spherical CuFe₂O₄magnetic nanoparticles are embedded in MgO Matrix. The Fourier Transform Infrared Spectroscopy (FTIR) results show the stretching and bending vibrations of tetrahedral and octahedral sites of ferrites along with vibration mode of MgO. The magnetic characterization has been performed by Vibrating Sample Magnetometer (VSM) at room temperature under the applied field of ±2T. The M-H loop of MgO shows ferromagnetic behavior at low field value of ±0.5 T due to oxygen vacancies defects and diamagnetic behavior at higher field value. On the other hand, the CuFe₂O₄nanoparticles shows normal superparamagnetic behavior with 30.78emu/gm saturation magnetization. Morever with the increase in concentration of MgO, the coercivity remains same but saturation magnetization decreases due to decrease in volume percent of magnetic contents. The electromagnetic wave absorption properties has been measured by vector analyzer in the frequency range of 2–10 GHz and best absorption reach to −25.35  dB at frequency of 8.38 GHz. Furthermore at higher concentration of MgO ≥40%, it covers the whole frequency band below −10 dB. This excellence microwave absorption may be due to the effective complementarities between dielectric and magnetic loss in this novel MgO/CuFe₂O₄nanocomposites.