Investigation on structural, magnetic, and FMR properties for hydrothermally-synthesized magnesium-zinc ferrite nanoparticles

Spinel ferrite nanoparticles with compositions of Mg1-xZnxFe2O47 (where x=0.4-0.7) were synthesized by the hydrothermal method from a mixture of metal nitrate hydrate solutions. In this study, the influences of changes in chemical composition (Zn content) on the structural features, magnetic parameters, and ferromagnetic resonance (FMR) characteristics of Mg-Zn ferrite nanoparticles are reported. X-ray diffraction (XRD) examination showed that the synthesized Mg-Zn ferrite nanoparticles had a spinel crystallite structure with an average nanocrystallite size in the range of 7.7-9.3 nm; transmission electron microscopy (TEM) micrographs displayed that the morphology of the nanoparticles was nearly spherical and that the average diameter of selected nanoparticles was in the range of 9.0-10.3 nm. The Raman spectra showed three major Raman modes (A(1g), E-g, and T-2g (2)), which are expected in the spinel ferrite structure. Measured results of magnetization showed that the obtained Mg-Zn ferrite nanoparticles exhibited a feature of soft magnetic materials; the saturation magnetization (M-s) and remanent magnetization (M-r) decreased with increases in Zn content, and the coercive field (H-c) was lower than 35 Oe in the studied range of Zn substitution.