Enhanced energy storage density by reversible domain switching in acceptor doped ferroelectrics

TL;DR

This study demonstrates that acceptor doping and aging induce reversible domain switching in ferroelectrics, leading to a pinched hysteresis loop with high polarization and low remanence, thereby significantly enhancing energy storage density.

Contribution

It introduces a novel defect engineering approach to achieve reversible domain switching in ferroelectrics, improving energy storage performance.

Findings

Reversible domain switching results in a pinched double hysteresis loop.

Enhanced energy storage density due to reduced remnant polarization.

The mechanism is demonstrated in BaTiO₃-based materials through simulations and experiments.

Abstract

Typical ferroelectrics possess a large spontaneous polarization Ps but simultaneously a large remnant polarization Pr as well, resulting in an inferior energy storage density.A mechanism that can reduce the Pr while maintain the Ps is demanded to enhance the energy storage property of ferroelectrics.In the present study, it is shown that after acceptor doping and aging treatment, the domain switching in ferroelectrics becomes reversible, giving rise to a pinched double hysteresis loop. The pinched loop with a large Ps and a small Pr thus results in an enhanced energy storage density. The physics behind is a defect induced internal field that provides a restoring force for the domains to switch back.The idea is demonstrated through a time-dependent Ginzburg-Landau simulation as well as experimental measurements in BaTiO$_3$ based single crystal and ceramics. The mechanism is general and can be applied to various ferroelectrics, especially the environment-friendly ones.