Ferroelectric, pyroelectric and dielectric properties of complex perovskite-structured Pb0.84Ba0.16(Zr0.44Ti0.40Fe0.08Nb0.08)O3 ceramics

Relaxor ferroelectrics with A'A"(B'B")O-3 - type perovskite structures have attracted much attention because of their excellent dielectric and electromechanical properties. The physical properties or device parameters of PZT can be tailored by improved synthesis and processing techniques and by making suitable substitutions into the A and/or B sites. In this study, Pb0.84Ba0.16(Zr0.44Ti0.40Fe0.08Nb0.08)O-3 ceramics were prepared by solid state reaction and the effect of the processing parameters on the ferroelectric, dielectric and pyroelectric properties was determined. Optimal dielectric properties were achieved in Pb0.84Ba0.16(Zr0.44Ti0.40Fe0.08Nb0.08)O-3 ceramics by calcination at 1100 degrees C and sintering at 1250 degrees C. Hysteresis loop measurements of these materials indicated a remanent polarization (P,) and spontaneous polarization (P-s) of 15.88 mu C/cm(2) and 26.29 mu C/cm(2), respectively. TEM micrographs showed nano-domains in the calcined powder confirming their ferroelectric properties. The dielectric properties also show ferroelectric behavior, with a Curie temperature of approximately 220 degrees C. The values of pi show a continuous increase with increasing temperature up to a maximum value similar to 800 nC/cm(2) K at similar to 120 degrees C. (c) 2007 Elsevier B.V. All rights reserved.