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Updated: Aug 14, 2026
06:44
From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
Reversible Colossal Barocaloric Effects in Hydrogen Bond-Engineered Plastic Crystals: chCl and [ch]2MnCl4
Yangxin Wang1,2,3, Jiazheng Hao1,3, Fengxia Hu4,5,6
1Institute of High Energy Physics, Chinese Academy of Sciences, Beijing100049, P. R. China.
Journal of the American Chemical Society
|August 12, 2026
Summary
Researchers enhanced sustainable cooling materials by modifying hydrogen bonds in choline-based plastic crystals. This boosts barocaloric performance and refrigeration capacity while reducing thermal hysteresis and transition temperatures.
Area of Science:
- Materials Science
- Thermodynamics
- Sustainable Technologies
Background:
- Plastic crystals offer large entropy changes for sustainable cooling.
- Practical use is limited by thermal hysteresis and unsuitable transition temperatures.
- Molecular structural variation, specifically hydrogen bond network modulation, is proposed for tuning properties.
Purpose of the Study:
- To investigate the effect of substituting chloride with tetrachloromanganate(II) in choline-based ionic plastic crystals.
- To tune the barocaloric performance, thermal hysteresis, and phase transition temperature of these materials.
- To explore the relationship between intermolecular interactions and barocaloric performance for efficient cooling applications.
Main Methods:
- Synthesized a modified choline-based ionic plastic crystal by substituting [Cl]- with [MnCl4]2-.
- Evaluated the barocaloric performance and refrigeration capacity under applied pressures (0.1 GPa).
- Quantified the reduction in thermal hysteresis and the change in phase transition temperature.
Main Results:
- Achieved a 2-fold enhancement in reversible barocaloric performance.
- Observed over a 500% increase in refrigeration capacity at 0.1 GPa.
- Reduced thermal hysteresis by over 68% and lowered the phase transition temperature by 19.5%.
Conclusions:
- Modulating the hydrogen bond network in choline-based ionic plastic crystals effectively tunes phase transition behavior.
- The modified material shows significant improvements in barocaloric performance and cooling capacity.
- This study provides a pathway for developing efficient and sustainable cooling materials.
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