Enhancement of coercivity, permeability, and dielectric properties of Co0.2Zn0.3Ni0.5EuxFe2–xO4 ferrites for memory and high frequency devices

Abstract

Spinel cubic ferrites have huge applications in memory and high frequency devices. For the improvement of these modern devices, the magnetic coercivity, permeability, and dielectric properties of a ferrite are the important issues. This article focuses on improving the magnetic coercivity, magnetic permeability, and dielectric properties of Co0.2Zn0.3Ni0.5EuxFe2–xO4 ferrites, where x = 0.00, 0.06, and 0.10. The X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX), vibrating sample magnetometer (VSM), and an impedance analyzer were used to characterize the structural, magnetic, and dielectric properties of the samples. The XRD patterns indicate the formation of spinel cubic structure of the samples with a secondary peak (EuFeO3) for Eu doped samples. The densities and porosities of the samples follow an inverse trend, where the doped samples’ lattice parameters are increased with the increment of rare earth Eu concentration. The FTIR analysis also proves the spinel cubic phase of the samples. The average grain size of the ferrites is obtained via FESEM images, and it is increased from 121 to 198 nm. VSM analysis confirms that doping of the Eu content also changes other hysteresis loop properties of Co0.2Zn0.3Ni0.5EuxFe2–xO4 ferrites. Particularly, the coercivity of the Eu doped samples is greater than that of the mother alloy (x = 0.00). The EDX study shows that there is no impurity contamination in the ferrites. The permeability and dielectric measurements show an improved quality factor of the Eu-doped samples with low magnetic and dielectric losses. Frequency dependent resistivity and impedance analysis also show the improved nature. From the observed properties of the samples, all the investigated ferrites might be strong candidates for potential applications in memory devices, magnetic sensors, and high frequency applications.