•  
  •  
 
Journal of Advanced Ceramics

Keywords

ferrimagnetic ceramics, impedance spectroscopy, electric modulus, temperature dependence

Abstract

The electrical properties of Ni0.27Cu0.10Zn0.63Fe2O4 (NCZF) prepared from auto combustion synthesis of ferrite powders have been studied by impedance and modulus spectroscopy. We studied frequency and temperature dependencies of impedance and electric modulus of NCZF in a wide frequency range (20 Hz–5 MHz) at different measuring temperatures TSM (30–225 ℃). The complex impedance spectra clearly showed both grain and grain boundary effects on the electrical properties. The observed impedance spectra indicated that the magnitude of grain boundary resistance Rgb becomes more prominent compared to grain resistance Rb at room temperature, and with the increase in TSM, Rgb decreases faster than the intrinsic Rb. The frequency response of the imaginary part of impedance showed relaxation behavior at every TSM, and the relaxation frequency variation with TSM appeared to be of Arrhenius nature and the activation energy has been estimated to be 0.37 eV. A complex modulus spectrum was used to understand the mechanism of the electrical transport process, which indicated that a non-Debye type of conductivity relaxation characterizes this material.

Publisher

Tsinghua University Press

Share

COinS