Composition dependent ferro-piezo hysteresis loops and energy density properties of mechanically activated (Pb1−xLax)(Zr0.60Ti0.40)O3 ceramics

Abstract

In the present study, ferroelectric and piezoelectric nature of La substituted lead zirconate titanate was investigated to decide the optimum La content. (Pb1−xLax)(Zr0.60Ti0.40)O3 (hereinafter PLZT x/60/40) ceramics were synthesized using novel processing approach of high energy ball milling and cold isostatic pressing (CIP). This study deals with two types of hysteresis loops, polarization (P–E) and strain vs. electric field (S–E) loops. Energy density properties, remanent polarization (Pr), coercive field (Ec), piezoelectric charge coefficient (d33), internal macroscopic electric field (Ein), domain switching current (Imax) and strain hysteresis, normalized strain coefficient (Smax/Emax) were also calculated to study the behaviour of PLZT x/60/40 ferroelectrics. In addition, current vs. electric field (I–E) curves were traced not only to support P–E studies and determination of the Ec but also to confirm the ferroelectricity and domain switching characteristics studies. The PLZT 8/60/40 electro-ceramics not only show the highest Pr ~ 29.1 μC/cm2, Imax ~ 2 mA, unipolar strain ~ 0.25% and average d33 ~ 632 pm/V but also the lowest Ec ~ 9.4 kV/cm and strain hysteresis loss ~ 4%.