K. S. Srikanth

Engineered microstructure for tailoring the pyroelectric performance of Ba0.85Sr0.15Zr0.1Ti0.9O3 ceramics by 3BaO-3TiO2-B2O3 glass addition

3BaO-3TiO2-B2O3 (BTBO) glass-added ferroelectric Ba0.85Sr0.15Zr0.1Ti0.9O3 (BST-BZT) ceramics were synthesized using a conventional solid state reaction route. BTBO glass settled at grain boundaries which has been confirmed from energy dispersive X-ray spectroscopy (EDX). Such effects were observed to benefit properties like the pyroelectric coefficient from 3.4 × 10−4 C/m2 K (0% glass) to 4.29 × 10−4 C/m2 K (2% by wt. glass) at 303 K. The dielectric constant decreased from 2937 to 2514 with 2% glass addition at 303 K (1 kHz). However, this reduction in dielectric constant increases the pyroelectric figure of merits (FOMs) for high current responsivity ( F i), voltage responsivity ( F v), detectivity ( F d), energy harvesting ( F e), and ( F e *) by 50%, 126%, 49%, 81%, and 76%, respectively, for 2% glass sample as compared with 0% glass at 303 K. Some of the FOMs even surpass the reported FOMs of well-known pyroelectric ceramics.

Effect of sintering parameters on the dynamic hysteresis scaling behavior of Ba0.85Sr0.15Zr0.1Ti0.9O3 ceramics

ABSTRACT This article presents the effect of processing parameters on the ferroelectric hysteresis behavior of Ba0.85Sr0.15Zr0.1Ti0.9O3 (BSZT) ceramics. The ferroelectric hysteresis scaling relations for coercive field (Ec) and remnant polarization (Pr) as a function of temperature have been proposed. The power law temperature exponents based on scaling were systematically established for all the hysteresis parameters. The temperature dependent scaling of Ec and Pr at sintering temperature of 1400, 1425, 1450 and 1475°C yields EcαT0.43, EcαT0.84, EcαT0.50, EcαT0.37 and PrαT−1.73, PrαT−1.55, PrαT−1.73, PrαT−1.69 respectively. Additionally, the scaling relations for the samples sintered at 1450°C at different time intervals of 3, 4, 5 and 6 hrs were also established. Finally, to understand the domain dynamics, back switching polarization (Pbc) as a function of temperature (T) was also estimated by Arrhenius law and the average activation energy was evaluated.