Structural, dielectric and magnetic properties of MWCNTs coated magnesium spinel ferrites nanocomposites

The demand for materials with enhanced dielectric and magnetic properties for high-frequency applications remains a challenge. This study investigates MgFe₂O₄/MWCNTs nanocomposites as a solution to these limitations. In this communication, the magnesium ferrite (MgFe₂O₄) nanoparticles were synthesized by sol gel auto combustion method and their (MgFe₂O₄)_1-x/(MWCNTs)_x; x = 0–0.25 were prepared using ultra-sonication with Multi-walled carbon nanotubes (MWCNTs). MWCNTs were uniformly dispersed within the ferrite matrix by functionalizing them with 50 ml of toluene. The prepared nanocomposites were thoroughly characterized with different techniques. X-ray diffraction (XRD) analysis confirmed the crystalline structure of both the pure nanoparticles and the nanocomposites. The crystallite size decreased from 20.89 nm to 14.02 nm with the incorporation of MWCNTs. Fourier transform infrared spectroscopy (FTIR) was used to investigate the phase formation of the nanocomposite. TEM (Transmission electron microscopy) analysis revealed morphology with a particle size around 15.2 nm. Dielectric and impedance were measured using an impedance analyzer in the frequency range of 1 MHz to 3 GHz at room temperature. These properties have massively changed with addition of the MWCNTs. A detailed study of polarization mechanisms with the effect of the increasing content of MWCNTs on the grain their boundaries have been discussed. The impedance of the nanocomposites has decreased. The Ac conductivity of the nanocomposites revealed an enhancement upon the addition of MWCNTs. At high frequency the peaks appeared in the dielectric properties verified the presence of the resonance effects. VSM was used to analyze the magnetic properties. The hysteresis loops confirmed the magnetic characteristics of the prepared samples. The magnetic parameters including saturation magnetization (M_s), coercivity (H_c) remanence magnetization (M_r), squareness (M_r/M_s) and anisotropic constant (K) were decreased with the addition of the MWCNTs. These results encourage that prepared nanocomposite can be used for microwave absorption properties, energy storage applications at high frequency and water purification applications.