International. A team of researchers from the Metals Research Institute of the Chinese Academy of Sciences found that one class of materials, plastic crystals, exhibited high temperature variations at low pressure and near room temperature.
These barocaloric effects (cooling effects of pressure-induced phase transitions) occur when entropy is exchanged between a material and the environment due to pressure change.
In the study led by Professor Li Bing, the team of researchers found that typical entropy changes with plastic crystals reach several hundred J/kg. K (joules per kilogram per kelvin).
For example, the advertised entropy change for the plastic crystal "neopentyl glycol" near room temperature is around 390 J kg-1 K-1, resulting in a high temperature change (50K).
Generally tested materials are about ten times less efficient.
The applications of these plastic crystals could be very promising because they are cheap, easy to produce, lightweight and non-toxic.
Source: www.nature.com
