Ferroelectric Characterization of Vanadium doped SBN

Abstract

SBT and vanadium doped SBT have been synthesized at 1000 °C and 900 °C
respectively by using mixed oxide solid state reaction method according to the compositional formula
SrBi2(Ta1-xVx)2O9 where x=0.00 and 0.15 with approximately 4 wt% excess Bi2O3.. Post sinter
annealing was performed on both virgin and Vanadium doped SBT samples and an effort have been
made to investigate the mechanism of formation of oxygen vacancy in a systematic and detailed
structural, and electrical study of SBT ceramics upon vanadium doping under fast heating rate and
different annealing times, since the electrical properties are strongly influenced by processing
parameters including the precursor preparation, pyrolysis temperature, and final annealing temperature.
XRD analyses indicated that a single phase layered perovskite structure was observed without any
detection of secondary phases up to 15% of vanadium doping in SBT. Low temperature synthesis of SBT
could minimize the high temperature bismuth losses in the material and provide a better profile of high
temperature dielectric loss and dielectric permittivity without even vanadium doping. Annealing also had
a significant impact on ferroelectric hysteresis of doped SBT ceramics. The PE loop analysis of annealed
sample of virgin SBT does not have any effect on hysteresis parameters and a good ferroelectric
hysteresis loop was developed in as sintered samples of SBT. Furthermore, the polarization switching
could not be possible within the applied voltage range even after 7.5 h annealing in case of vanadium
doped samples. Polarization could only be switched after performing 24 h annealing on vanadium doped
SBT sample. Hysteresis behavior was quite in agreement with the observed dielectric properties of the
ceramics.