Anti-Ferroelectric Ceramics for High Energy Density Capacitors

Abstract

With an ever increasing dependence on electrical energy for powering modern equipment and electronics, research is focused on the development of efficient methods for the generation, storage and distribution of electrical power. In this regard, the development of suitable dielectric based solid-state capacitors will play a key role in revolutionizing modern day electronic and electrical devices. Among the popular dielectric materials, anti-ferroelectrics (AFE) display evidence of being a strong contender for future ceramic capacitors. AFE materials possess low dielectric loss, low coercive field, low remnant polarization, high energy density, high material efficiency, and fast discharge rates; all of these characteristics makes AFE materials a lucrative research direction. However, despite the evident advantages, there have only been limited attempts to develop this area. This article attempts to provide a focus to this area by presenting a timely review on the topic, on the relevant scientific advancements that have been made with respect to utilization and development of anti-ferroelectric materials for electric energy storage applications. The article begins with a general introduction discussing the need for high energy density capacitors, the present solutions being used to address this problem, and a brief discussion of various advantages of anti-ferroelectric materials for high energy storage applications. This is followed by a general description of anti-ferroelectricity and important anti-ferroelectric materials. The remainder of the paper is divided into two subsections, the first of which presents various physical routes for enhancing the energy storage density while the latter section describes chemical routes for enhanced storage density. This is followed by conclusions and future prospects and challenges which need to be addressed in this particular field.

Pulse discharge properties of PLZST antiferroelectric ceramics compared with ferroelectric and linear dielectrics

“…3(c) illustrates the capacitance C of PLZST10 versus E. At low field the value of C only increase slightly, but when E approaches 8kV/mm, the value of C grows rapidly due to the AFE-FE phase transition. 16,17 According to the expression of I max and equation (6), the increase of both E and C will result in a rise of increase rate of I max . Above 8 kV/mm, the field-induced FE phase becomes stable.…”

Nonequilibrium polarization dynamics in antiferroelectrics

“…Antiferroelectrics display a field induced transition from antipolar to polar dielectric, and they have interesting properties such as the double hysteresis loop and large strains associated with it. These unique properties make antiferroelectric materials very attractive for technological applications involving high-energy supercapacitors [4][5][6][7][8], electrocaloric cooling [9], actuators [10], photovoltaic effects [11], and many other interesting dielectric phenomena. Very recently, experimental evidence of a novel four-state nonvolatile memory effect in antiferroelectrics was reported [12].…”

Ionic Mobility and Phase Transitions in Perovskite Oxides for Energy Application

“…In this manner it is shown that even the diffusion of O vacancies at high dilution, 1%, in the simple cubic SrTiO 3 is far from the diffusion of dispersed isolated vacancies, but involves pairing and formation of larger complexes, possibly longer chains. It is clear that a knowledge of this type is necessary for improving the properties of ionic conductors, but the realistic cases of solid electrolytes for fuel cells, highly doped with acceptors in order to be made oxide or proton conductors, are predictably much more complicated than SrTiO 3 . From the large amount of information contained in the anelastic and dielectric spectra of such materials only a part can be interpreted in relatively direct manner, and much remains to be done.…”

“…Examples are the oxygen and proton conductors as solid electrolytes for fuel cells (SOFCs) [1], and the ferroelectric (FE) and antiferroelectric (AFE) compositions, which may find application in high energy capacitors for energy storage [2,3], efficient electrocaloric cooling [4], and electromechanical energy harvesting [5]. Figure 1 presents the cell of a cubic perovskite ABO 3 and ranges of different properties depending on the choice of the A and B cations. When the −6e charge of the ideally three O 2− atoms per unit cell is not fully compensated by the cation valence v A + v B , then V O are created and this can be exploited for creating a fast ion conductor.…”