Frequency dependent dielectric behaviour of cadmium and chromium co-substituted nickel ferrite

Abstract

The frequency dependent dielectric properties of Ni 1 - x Cd x Cr x Fe 2 - x O 4 (x = 0.0, 0.3, 0.5, 0.7 and 1.0) spinel ferrite system are studied by measuring dielectric constant (e'), dielectric loss (D) and conductivity (σ a , c ) at 300 K in the frequency range 100 Hz-2 MHz. The highest value of σ a . c and e' is observed for x = 0.3 composition. The values e' and σ a . c decrease with increase in frequency for all the compositions, exhibiting normal ferrimagnetic behaviour and are attributed to Maxwell-Wagner type interfacial polarization. The observed broadening of relaxation peak with content in dielectric loss versus frequency curve is due to the strengthening of dipole-dipole interactions.