Direct measurement of giant electrocaloric effect in BaTiO3 multilayer thick film structure beyond theoretical prediction

TL;DR

This study directly measured the electrocaloric effect in BaTiO3 multilayer thick films, revealing a significantly higher effect than theoretical predictions, indicating potential for advanced cooling applications.

Contribution

It provides the first direct measurement of the electrocaloric effect in multilayer BaTiO3 films, showing effects beyond theoretical expectations.

Findings

Measured electrocaloric effect of 0.91J/g at 80°C

The effect exceeds theoretical prediction of 0.32J/g

Differences attributed to polarization and elastic energy changes

Abstract

The electrocaloric effect of BaTiO3 multilayer thick film structure was investigated by direct measurement and theoretical calculation. The samples were prepared by the tape-casting method, which had 180 dielectric layers with an average thickness of 1.4\mu m. The thermodynamic calculation based on the polarization- temperature curves predicted a peak heat adsorption of 0.32J/g at 80^\circC under 176kV/cm electric field. The direct measurement via differential scanning calorimeter showed a much higher electrocaloric effect of 0.91J/g at 80^\circC under same electric field. The difference could result from the different trends of changes of electric polarization and lattice elastic energy under ultrahigh electric field.