Effect of γ-rays irradiation on the structural, magnetic, and electrical properties of Mg–Cu–Zn and Ni–Cu–Zn ferrites

●Samples of NiCuZn and MgCuZn ferrites, were synthesized by citrate precursor method.●The effect of irradiation dose on the some physical properties have been investigated.●Both samples are promising candidates to be used in manufacturing multilayer chip inductors.

Nanoparticles of Ni0.35Cu0.15Zn0.5Fe2O4 and Mg0.35Cu0.15Zn0.5Fe2O4, have been synthesized by citrate precursor method. Then some of the prepared samples have been irradiated by γ-rays of 60Co radioactive source at room temperature with doses of 1 Mrad and 2 Mrad, at a dose rate of 0.1 Mrad/h to study the effect of γ-rays irradiation on some structural, magnetic and electrical properties of the samples. The X-ray diffraction analysis (XRD), transmission electron microscopy, Fourier transform infrared spectroscopy and vibrating sample magnetometer measurements have been used to investigate the samples. The XRD results show that the irradiation has caused a decrease in the crystallite size and the measured density and an increase in the porosity, specific surface area, and microstrain in the case of Ni–Cu–Zn ferrite whereas in the case of Mg–Cu–Zn ferrite the reverse trend has been noticed. The lattice constant of the investigated samples has been increased with the increase of irradiation due to the conversion of Fe3+ (0.67 Å) to Fe2+ (0.76 Å). The magnetization results show an increase in saturation and remnant magnetizations for the two prepared ferrites after γ-rays irradiation. The main reason of this behavior is most probably due to the redistribution of the cations between A and B sites. The cation distribution has been proposed such that the values of theoretical and experimental magnetic moment are identical and increase as the magnetization increases. Moreover, a theoretical estimation of the lattice constant has been calculated on the basis of the proposed cation distribution for each sample and compared with the corresponding experimental values obtained by XRD analysis; where they have been found in a good agreement with each other. This can be considered as another confirmation of the validity of the cation distribution. Moreover, the cation distribution is thought to play an important role in increasing the values of dc conductivity of all samples with increasing the irradiation dose. The frequency dependence of ac conductivity, dielectric constant and dielectric loss of all samples have been studied. The Cole–Cole plots of (Z″ vs. Z′) give different two overlapping incomplete semi-circles depending upon the electrical parameters. Also, The Cole–Cole plots of (M″ vs. M′) insure that the electric stiffness is the dominant property of the investigated samples.