Synthesis and characterization of Cr substituted Mn-Zn nanoferrites with improved dielectric, electrical conductivity and impedance properties for electronic device applications

In the present study, the impact of Cr ion substitution on Mn-Zn soft nanoferrites has enhanced the dielectric, electrical conductivity, and impedance properties. The nanoferrites have been synthesized via a non-conventional wet chemical-based co-precipitation technique. Raman scattering confirms the spinel nature and also reveals a positive frequency shift with the Cr ion substitution. As Cr ion concentration increases, the dielectric constant (epsilon') increases significantly at room temperature. At 100 Hz, x= 0.5 [Mn0.5Cr0.5Fe2O4] resulted in higher value of epsilon' similar to 10(4) and a lower value of loss (tan delta) similar to 3.9. Frequency modulated ac conductivity rises with increasing Cr substitution in Mn-Zn nanoferrites. Electric modulus, impedance spectra, and conduction nature were found to improve with increasing Cr ions. The Nyquist plot shows two semicircle responses in the high and mid-frequency regions, which is due to a conduction mechanism of charges (Fe2+<-> Fe3+) that is related to bulk grains and grain boundary contribution, respectively. High dielectric constants and minimum electric loss in soft nanoferrite materials are useful for electronic device applications.