Analysis on discharge behavior of antiferroelectric ceramics for pulse capacitors

Abstract

At present, the research on the discharge of antiferroelectric materials is incomprehensive. For purpose of further studying the discharge behavior of antiferroelectric materials for pulse capacitors, (Pb0·98La0.02)(Zr0·45Sn0.55)0.995O3(PLZS) and (Pb0·98La0.02)(Zr0·55Sn0·35Ti0.10)0.995O3(PLZST) with different types of hysteresis loops were prepared, which had “slanted” and “squared” hysteresis loops, respectively. The variation trend of discharge current of them was consistent with that of hysteresis loop. The new method of “equivalent capacitance” was proposed, which was obtained by fitting the discharge curve of the underdamped circuit to calculate the energy storage density. The energy density of PLZS was calculated in different ways, the energy density obtained from the discharge process, Wdis (overdamped, 0.89 J/cm3) and WC (“equivalent capacitance”, 0.74 J/cm3), are smaller than that calculated from the hysteresis loop, Wre (1.31 J/cm3). In addition, because the pulse discharge process is closer to the practical application of dielectric capacitors, the energy density obtained under the pulse discharge process is more reasonable and reliable than that obtained by the hysteresis loop. At the same time, the new method of “equivalent capacitance” could be adopted as a reference for the calculation of energy density.