Enhancement of the electrocaloric cooling by electric field reversal: simulation and experiment

TL;DR

This paper introduces a novel electrocaloric cooling cycle that uses electric field reversal to significantly improve cooling efficiency, supported by simulations and experiments demonstrating over 20% enhancement.

Contribution

The study proposes and validates a new thermodynamic cycle employing electric field reversal to enhance electrocaloric cooling efficiency in ferroelectric materials.

Findings

Cooling efficiency increased by more than 20%

Effective in both standard and relaxor ferroelectrics

Validated through simulations and experimental measurements

Abstract

An improved thermodynamic cycle is proposed, where the cooling effect of an electrocaloric refrigerant is enhanced by applying a reversed electric field. In contrast to conventional adiabatic heating or cooling by on-off cycles of the external electric field, applying a reversed field is significantly improving the cooling efficiency, since the variation in configurational entropy is increased. By comparing results from computer simulations using Monte-Carlo algorithms and experiments using direct electrocaloric measurements, we show that the electrocaloric cooling efficiency can be enhanced by more than 20\% in standard ferroelectrics and also relaxor ferroelectrics, like Pb(Mg$_{1/3}$/Nb$_{2/3}$)$_{0.71}$Ti$_{0.29}$O$_3$.