Advances and obstacles in pressure-driven solid-state cooling: A review of barocaloric materials

Barocaloric methods offer the widest range among solid-state caloric materials where to pick and choose. However, ideal barocaloric materials do not exist and a trade-off is required; Materials with high refrigerant capacity suffer from poor thermal conductivity and low density, and conversely. Solid-state caloric effects promise since decades a disruptive cooling technology that should be more efficient and cleaner than current vapor compression. However, despite relevant achievements have been made, it is still difficult to foresee the time left for the development and wide implementation of competitive devices. Recent progress in the response of materials under hydrostatic pressure offers hope for overcoming some of the shortcomings posed by other solid-state methods and augurs a good outlook for barocaloric cooling, but there are still many struggles ahead to address in order to demonstrate its viability as a commercial cooling technique. Here we briefly review the milestones achieved in terms of barocaloric materials and discuss the pending challenges and expectations for the oncoming years.