Giant room-temperature barocaloric effects in PDMS rubber at low pressures

TL;DR

This paper reports giant barocaloric effects in PDMS rubber at low pressures near room temperature, with significant entropy and temperature changes, suggesting potential for solid-state cooling applications.

Contribution

It demonstrates unprecedented barocaloric effects in PDMS elastomer at low pressures, expanding the scope of materials for cooling technologies.

Findings

Adiabatic temperature changes up to 28.5 K at 390 MPa

Entropy change exceeding 140 J kg-1 K-1

Barocaloric effects surpass previous materials at room temperature

Abstract

The barocaloric effect is still an incipient scientific topic, but it has been attracting an increasing attention in the last years due to the promising perspectives for its application in alternative cooling devices. Here, we present giant values of barocaloric entropy change and temperature change induced by low pressures in PDMS elastomer around room temperature. Adiabatic temperature changes of 12.0 K and 28.5 K were directly measured for pressure changes of 173 MPa and 390 MPa, respectively, associated with large normalized temperature changes (~70 K GPa-1). From adiabatic temperature change data, we obtained entropy change values larger than 140 J kg-1 K-1. We found barocaloric effect values that exceed those previously reported for any promising barocaloric materials from direct measurements of temperature change around room temperature. Our results stimulate the study of the barocaloric effect in elastomeric polymers and broaden the pathway to use this effect in solid-state cooling technologies.