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Extreme barocaloric effect at dissolution
Kun Zhang1,2, Yifang Liu1,2, Ying Gao3
1Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang, China.
Nature
|January 21, 2026
Summary
A novel barocaloric refrigeration method using ammonium thiocyanate (NH4SCN) aqueous solutions offers a sustainable, low-carbon alternative. This approach achieves unprecedented cooling capacity and efficiency, surpassing existing caloric materials for practical cooling applications.
Area of Science:
- Materials Science
- Thermodynamics
- Sustainable Energy
Background:
- Vapour-compression refrigeration dominates but uses harmful fluorocarbons.
- Solid-state caloric refrigeration is a promising low-carbon alternative but faces challenges.
- Existing methods suffer from limited cooling capacity and inefficient heat transfer.
Purpose of the Study:
- To explore a novel barocaloric effect in NH4SCN aqueous solutions.
- To overcome limitations of current refrigeration technologies.
- To develop a high-capacity, efficient, and sustainable cooling solution.
Main Methods:
- Investigated pressure-tuned dissolution and precipitation in NH4SCN aqueous solutions.
- Demonstrated an extreme barocaloric effect.
- Designed and simulated a Carnot-like cycle for the system.
Main Results:
- Achieved an in situ temperature drop of 26.8 K at room temperature.
- Reported a cooling capacity of 67 J g⁻¹ per cycle.
- Attained a second-law efficiency of 77% with direct heat transfer.
Conclusions:
- NH4SCN aqueous solutions exhibit an extreme barocaloric effect for efficient refrigeration.
- The dissolution-based approach offers a sustainable alternative to conventional refrigerants.
- This method presents a promising pathway for practical, high-performance, and eco-friendly cooling systems.
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