Impedance Spectroscopy Characterization of ZnCo₂O₄ Ceramics Obtained by the Sol-Gel Method

In this article, structural, morphological and electrical properties of ZnCo2O4 ceramics sample were studied. ZnCo2O4 nanoparticles were synthesized using sol-gel method. Structural and morphological properties of the sample were analyzed using X-ray diffraction and scanning electron microscope. Conductance, capacitance and impedance spectroscopy characterization of ZnCo2O4 ceramics sample were analyzed in 3 kHz-1.5 MHz frequency range and 300-500 K temperature range. Nyquist diagrams of impedance and the equivalent circuit were studied for ZnCo2O4 ceramics in the temperature range of 300-500 K. Cole-Cole curves of the impedance data were found to show a semicircular arc in both low and high temperature areas, which is expressed by the equivalent electrical circuit R-s (RgC (g))(R(gb)QC(gb) ). Relaxation behavior was identified to be of non-Debye type. The Cole-Cole curve showed the negative temperature coefficient of resistance type behavior. Values of the activation energy corresponding to relaxation processes were found as 0.054 eV below 360 K and 0.561 eV above 360 K.