Studies of electrical and magnetic properties of Mn-, Zn- and Ti-substituted lithium ferrites

Substituted lithium ferrite with the formula Li_0.375−xZn_0.15Ti_0.05Mn_xFe_2.375−xO₄ with x ranging from 0.00 to 0.10 with a step size of 0.02 was prepared with the help of solid-state ceramic method. The samples were sintered at 1000 °C for 2 h with the help of resistive heating. X-ray diffraction (XRD) studies confirmed the single phase with spinel structure in all the prepared samples. Rietveld analysis was used to analyse the XRD data obtained. The bulk density of the prepared samples was measured with the help of Archimedes principle and along with the data obtained from X-ray density, respective porosities were calculated. The Curie temperature was determined using the sample drop method which showed a decrease with the increase in Mn concentration. Frequency variation of electrical parameters such as dielectric constant, dielectric loss, real impedance and imaginary impedance were traced in the range of 20 to 5 MHz and a dispersive spectrum was obtained. Nyquist impedance plot studies helped in the understanding of conduction mechanisms. The initial permeability and permeability loss traced as a function of frequency are found to exhibit resonance. M–H loops were traced for the samples and showed an increase in coercivity with the incorporation of Mn ions. The findings obtained have been examined in the paper.