Structural and Initial Permeability Studies of Li-Zn-Co Ferrites.

A series of cobalt substituted lithium zinc ferrites having the compositional formula Li0.4-0.5xZn0.2CoxFe2.4-0.5xO4, where 0.00 ≤ x ≤ 0.1 in steps of 0.02, was prepared by the citrate precursor method. Structural studies on the prepared samples were carried out by using XRD and SEM measurements. Spinel phase structure of the samples was confirmed by XRD. From the XRD data the lattice parameter and the theoretical density were calculated. The experimental density was also determined using the Archimedes principle. Lattice parameter was observed to increase with increasing Co2+ ion concentration. The densification in both the cases, theoretical and experimental, shows an increase with composition. SEM studies carried out show that average grain diameter are in the range of 300 nm-650 nm and a fall is observed with increasing Co2+ ion content. The investigation on initial permeability as a function of composition and frequency were also undertaken. It is seen that there is decrease in the value of initial permeability with addition of Co content. The initial permeability and permeability loss show dispersion with frequency. Possible mechanisms contributing to the above processes are discussed. [ABSTRACT FROM AUTHOR]