Structural and dielectric behaviour of barium substituted lead zinc niobate ceramics at low temperature

Abstract

The polycrystalline samples of (Pb(1-x)Ba(x))(Zn(1/3)Nb(2/3))O(3) (PBZN) ceramics have been synthesis by the columbite precursor method. X-ray diffraction analysis of PBZN synthesized For x = 0.15, 0.25, 0.35 and 0.50 shows a cubic perovskite phase at room temperature. The changes in the structures arc observed with increasing Ba contents in PBZN. The dielectric dispersion of the solid solutions has been studied as a function of temperature in the frequency range 100 Hz-1MHz. The temperature variation of the real components (epsilon') at different frequencies of the dielectric permittivity shows a broad maximum. The diffuse peaks in epsilon' versus T confirm the relaxor behaviour of PBZN. The changes in the relaxor properties of the compounds arc found to be compositional dependent. The frequency dependence of T(m) in these compounds with barium substitution is modeled using Vogel-Fulcher relation.