Fabrication of a lead-free ternary ceramic system for high energy storage applications in dielectric capacitors

Azam Khan; Noor Shad Gul; Mao Luo; Jianbo Wu; Shahan Zeb Khan; Abdul Manan; Xiu-Jian Wang; Taj Malook Khan

doi:10.3389/fchem.2022.1025030

Fabrication of a lead-free ternary ceramic system for high energy storage applications in dielectric capacitors

Front Chem. 2022 Oct 19:10:1025030. doi: 10.3389/fchem.2022.1025030. eCollection 2022.

Authors

Azam Khan¹, Noor Shad Gul^{2

3}, Mao Luo^{2

3}, Jianbo Wu^{2

3}, Shahan Zeb Khan⁴, Abdul Manan⁵, Xiu-Jian Wang¹, Taj Malook Khan^{2

3}

Affiliations

¹ School of Chemistry and Pharmacy, Guangxi Normal University, Guilin, China.
² Drug Discovery Research Center, Southwest Medical University, Luzhou, China.
³ Department of Pharmacology, Laboratory for Cardiovascular Pharmacology, School of Pharmacy, Southwest Medical University, Luzhou, China.
⁴ Department of Chemistry, University of Science and Technology, Bannu, Pakistan.
⁵ Advanced Materials Research Laboratory, Department of Physics, University of Science and Technology Bannu, Bannu, Pakistan.

Abstract

The importance of electroceramics is well-recognized in applications of high energy storage density of dielectric ceramic capacitors. Despite the excellent properties, lead-free alternatives are highly desirous owing to their environmental friendliness for energy storage applications. Herein, we provide a facile synthesis of lead-free ferroelectric ceramic perovskite material demonstrating enhanced energy storage density. The ceramic material with a series of composition (1-z) (0.94Na_0.5Bi_0.5TiO₃-0.06BaTiO₃)-zNd_0.33NbO_3, denoted as NBT-BT-zNN, where, z = 0.00, 0.02, 0.04, 0.06, and 0.08 are synthesized by the conventional solid-state mix oxide route. Microphases, microstructures, and energy storage characteristics of the as-synthesized ceramic compositions were determined by advanced ceramic techniques. Powder X-ray diffraction analysis reveals pure single perovskite phases for z = 0 and 0.02, and secondary phases of Bi₂Ti₂O₇ appeared for z = 0.04 and 0.08. Furthermore, scanning electron microscopy analysis demonstrates packed-shaped microstructures with a reduced grain size for these ceramic compositions. The coercive field (E_c) and remnant polarization (P_r) deduced from polarization vs. electric field hysteresis loops determined using an LCR meter demonstrate decreasing trends with the increasing z content for each composition. Consequently, the maximum energy storage density of 3.2 J/cm³, the recoverable stored energy of 2.01 J/cm³, and the efficiency of 62.5% were obtained for the z content of 2 mol% at an applied electric field of 250 kV/cm. This work demonstrates important development in ceramic perovskite for high power energy storage density and efficiency in dielectric capacitors in high-temperature environments. The aforementioned method makes it feasible to modify a binary ceramic composition into a ternary system with highly enhanced energy storage characteristics by incorporating rare earth metals with transition metal oxides in appropriate proportions.

Keywords: dielectric capacitors; perovskite; pulsed power; recoverable energy; temperature.