Densification, magnetic and dielectric investigations of Mg-substituted Li–Zn ferrites

A series of Li_0.5Zn_0.2Mg _x Fe_2.3−x O_4−σ (0 ≤ x ≤ 0.20) ferrites were successfully synthesized by sol–gel method, and the lattice structure, densification, surface morphology, magnetic and dielectric properties were investigated. The XRD results showed that the lattice constant increases linearly with the increase in Mg content. Moreover, the magnetic properties of Mg-substituted Li–Zn ferrite were also strongly dependent on Mg content. The saturation magnetization (M _s) and initial permeability (µ _i ) first decrease and then increase with the increase in concentration of Mg. This phenomenon can be ascribed to the variation of A–B interactions. Differently, the coercivity (H _c) of samples increases significantly and Curie temperature (T _c) decreases gradually. Both dielectric constant and dielectric loss show reduction with the increase in Mg content, and they remain stable at high frequency.