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arXiv · 1903.12010

Colossal barocaloric effects near room temperature in plastic crystals of neopentylglycol

Pol Lloveras·Araceli Aznar·María Barrio·Philippe Negrier·Catalin Popescu·Antoni Planes·Lluís Mañosa·Enric Stern-Taulats·Alex Avramenko·Neil D. Mathur·Xavier Moya·Josep-Lluís Tamarit
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Abstract

There is currently great interest in replacing the harmful volatile hydrofluorocarbon fluids used in refrigeration and air-conditioning with solid materials that display magnetocaloric, electrocaloric or mechanocaloric effects. However, the field-driven thermal changes in all of these caloric materials fall short with respect to their fluid counterparts. Here we show that plastic crystals of neopentylglycol (CH3)2C(CH2OH)2 display unprecedentedly large pressure-driven thermal changes near room temperature due to molecular reconfiguration, and that these changes are comparable with those exploited commercially in hydrofluorocarbons. Our discovery of colossal barocaloric effects in a plastic crystal should bring barocaloric materials to the forefront of research and development in order to achieve safe environmentally friendly cooling without compromising performance.

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Pol Lloveras, Araceli Aznar, María Barrio, Philippe Negrier, Catalin Popescu, Antoni Planes, Lluís Mañosa, Enric Stern-Taulats, Alex Avramenko, Neil D. Mathur, Xavier Moya, Josep-Lluís Tamarit. 2019-03-28. Colossal barocaloric effects near room temperature in plastic crystals of neopentylglycol. https://doi.org/10.1038/s41467-019-09730-9

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