Complex impedance and modulus studies of cerium doped barium zirconium titanate solid solution

Abstract

Nanocrystalline powders of (Ba1-xCe x)(Zr0.52Ti0.48)O3 [x = 0.1 and 0.2] have been synthesized by conventional solid state reaction method. X-ray diffraction patterns confirm the formation of single phase cubic crystal symmetry. The increase in grain size reveals the influence of Ce ions on microstructure. The electrical behavior of sintered pellets investigated by impedance spectra showed frequency dependent behavior. The complex impedance plots display a single semicircle highlighting the influence of grain resistance on the electrical behavior. The modulus curve illustrates the possibility of non-exponential type conductivity. The values of activation energy calculated from both plots of Z? and M? confirms that the oxygen vacancies play an important role in the conduction. The temperature dependant dc-resistivity depicts a negative temperature coefficient of resistance behavior of synthesized ceramics. The ac conductivity of both ceramics increases as a function of frequency due to relaxation phenomenon arisen due to mobile charge carriers. © 2012 Elsevier B.V. All rights reserved.