Refrigeration thanks to plastic crystals

Researchers have found that "plastic crystals" undergo particularly high temperature variations when subjected to pressure changes. These materials could be used for the development of the promising technology of barocaloric refrigeration.

A team of researchers at the Institute of Metals Research at the Chinese Academy of Sciences discovered that a class of materials, plastic crystals, exhibited high temperature variations under low pressure and near room temperature.

These barocaloric effects occur when entropy is exchanged between a material and the environment due to pressure change.

In the study1 led by Professor Li Bing, the team of researchers found that typical entropy changes with plastic crystals reach several hundred J / kg.K.

For example, the entropy change announced for the "neopentylglycol" plastic crystal near ambient temperature is about 390 J kg-1 K-1, resulting in a high temperature change (50K).

The materials usually tested are about ten times less efficient.

The applications of these plastic crystals could therefore be very promising because they are cheap, easy to produce, light and non-toxic.

1 Colossal barocaloric effects in plastic crystals. Bing Li, Yukinobu Kawakita, Seiko Ohira-Kawamura, et al. Nature. 2019, vo. 567, pp. 506-510. Available following this link.