Exploring the structural, magnetic, dielectric and electrical properties of solid state method synthesized Mn3+ substituted Co–Zn ferrites

Abstract

Co–Zn ferrites have already been familiar for their outstanding properties, including large saturation magnetization and high permeability over a broad frequency range. Herein, Co–Zn ferrites with the partial substitution of Mn in place of Fe have been prepared by solid state method for sintering temperature 1200 °C in air for 3 h and their structural, magnetic, dielectric and electrical properties have been investigated. The synthesized Mn-free and Mn-doped Co–Zn ferrites show a single phase with cubic spinel structure. The lattice parameter exhibited an increasing trend whereas the grain size showed an opposite manner with the increase in Mn substitutions in place of Fe. An enhanced saturation magnetization is noted after substituting 1 wt% Mn for Fe. Additionally, all the ferrite samples showed low coercivity (~ 12–40 Oe) values, indicating they belong to the family of soft ferrites. The permeability values are observed to decline gradually with the substitution of Mn, which can be attributed to the decrease in grain size as well as bulk density. The quality factor showed a gradual reduction with Mn substitution, however shifted toward higher frequencies. The dielectric dispersion exhibited a rapid decrease in the lower frequency range before practically remaining constant in the high frequency region beyond that a random nature. The explored dielectric behavior is an usual characteristics of ferrite materials, which can be realized by the Maxwell–Wagner interfacial polarization and Koop’s theory. The AC resistivity is obtained in the order of ~ 10⁵–10⁶ Ω-m at low frequency region, indicating a semiconducting nature of the samples. Overall investigations suggest that Mn-substituted Co–Zn ferrites can be a good candidate to use in modern electromagnetic devices operating for high frequency regions.