Kinetic electrocaloric effect and giant net cooling of lead-free ferroelectric refrigerants

TL;DR

This paper reports a giant electrocaloric effect in BaTiO3 multilayer films, with a significant temperature change and net cooling dependent on the rate of electric field variation, offering new insights for ferroelectric refrigeration.

Contribution

It introduces the kinetic electrocaloric effect in lead-free ferroelectric films and demonstrates its potential for efficient micro-refrigeration applications.

Findings

Temperature change up to 4.0°C under high electric field

Net cooling of approximately 0.37 J/g due to rate-dependent effects

Dependence of electrocaloric effect on the rate of electric field variation

Abstract

Giant electrocaloric (EC) effect is observed in BaTiO3 multilayer thick film structure. The temperature change is as high as 4.0 oC under an applied electric field of 352 kV/cm. Most importantly, the EC effect is found to depend on the varying rate of the applied field. Based on the giant net cooling (~0.37 J/g) resulting from the difference in the varying rates of rising and falling fields, the kinetic EC effect provides an effective solution for the design of refrigeration cycle in ferroelectric micro-refrigerator.