Effect of MoO3 Addition on the Magnetic Properties and Complex Impedance of Mn-Zn Ferrites with High Bs and High Initial Permeability

Mn-Zn ferrites with high initial permeability (mu(i)) and high saturation magnetic flux density (B-s) were successfully synthesized by using a conventional ceramic processing route with addition of MoO3. The structure, morphology, magnetic properties, and complex impedance of all samples were investigated by X-ray diffraction, scanning electron microscopy, DC magnetic instrument, and precision LCR meter. The addition of MoO3 promotes the growth of larger and more uniform grains and therefore enhances the mu(i). Meanwhile, it improves the density and hence the Bs. Through the analysis of complex impedance spectra by an equivalent circuit model, it is demonstrated that MoO3 mainly exists at grain boundaries and improves the impedance in a wide frequency range.