Antiferroelectricity in a family of pyroxene-like oxides with rich polymorphism

Hugo Aramberri,Jorge Íñiguez

doi:10.1038/s43246-020-00051-9

Abstract

Antiferroelectrics have potential applications in energy conversion and storage, but are scarce, particularly among oxides that otherwise display rich ferroic behaviours. A question then arises whether potential antiferroelectrics are being overlooked, simply because their corresponding ferroelectric phase has not been discovered yet. Here we report a first-principles study suggesting that this is the case for a family of ABO3 pyroxene-like materials, characterised by chains of corner-sharing BO4 tetrahedra, a well-known member being KVO3. The irregular tetrahedra have an electric dipole associated to them. In the most stable polymorph, the dipoles display an antipolar pattern with zero net moment. However, upon application of an electric field, half of the tetrahedra rotate, flipping the corresponding dipoles and reaching a ferroelectric state. We discuss the unique possibilities for tuning and optimisation of antiferroelectricity that these materials offer. We suggest that the structural features enabling this antiferroelectric behaviour can also be found in other all-important mineral families.

Highlights

Antiferroelectrics have potential applications in energy conversion and storage, but are scarce, among oxides that otherwise display rich ferroic behaviours
Applications of antiferroelectrics rely on their unique response to an applied electric bias, featuring a double hysteresis loop that is the result of a fieldinduced phase transition to a polar state
In order to identify stable structures, we run first-principles molecular dynamics simulations of several alkali vanadates

Summary

Introduction

Antiferroelectrics have potential applications in energy conversion and storage, but are scarce, among oxides that otherwise display rich ferroic behaviours. Applications of antiferroelectrics rely on their unique response to an applied electric bias, featuring a double hysteresis loop that is the result of a fieldinduced phase transition to a polar state. One could proceed as follows: chosen a materials family and a pertinent high-symmetry structure (e.g. the ideal cubic phase of perovskite oxides ABO3), one could use first-principles simulations to find compositions that present strong polar and antipolar phonon instabilities of this parent phase. Any such compound is likely to present metastable polar and antipolar polymorphs of similar energy. The chains can alternatively follow a 1D battlement-like (BM) pattern along the [010]

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Results

Conclusion