Impedance analysis, dielectric relaxation and modulus behaviour of ZnO-Sn2O3 ceramics

We report the synthesis of Sn2O3-ZnO composites by solid-state reaction method for 0 wt%, 5 wt%, 10 wt% and 15 wt% of Sn2O3 amount. The effect of interstitial tin incorporation on structural, dielectric and electrical properties of ZnO pellets was investigated. The microstructure of the ZnO pellets is characterized by means of the X-ray diffraction (XRD). The electrical response of ZnO-Sn2O3 pellets were analyzed using impedance spectroscopy. The impedance spectra were explored with the help of an equivalent circuit including CPE capacitor which indicate a significant contribution of grain boundary resistance. The real part (ε′) of the complex permittivity and the dielectric loss (ε″) were studied as the function of frequency and composition. Impedance and modulus study reveals non-Debye type relaxation phenomenon. Dielectric studies depicted promising dielectric properties. And the results of activation energy suggest different kinds of defects in the grain boundary region.