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Updated: Jul 5, 2025
08:12
Low Pressure Vapor-assisted Solution Process for Tunable Band Gap Pinhole-free Methylammonium Lead Halide Perovskite Films
Published on: September 8, 2017
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Barocaloric Effects in Dialkylammonium Halide Salts.
Jinyoung Seo1, Rahil Ukani1, Juanjuan Zheng2
1Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States.
Journal of the American Chemical Society
|January 16, 2024
Summary
Dialkylammonium halides exhibit significant barocaloric effects for efficient solid-state cooling. These organic salts show large, reversible thermal changes near room temperature, offering a sustainable alternative to traditional refrigerants.
Area of Science:
- Materials Science
- Thermodynamics
- Solid-state physics
Background:
- Barocaloric effects offer potential for energy-efficient heating and cooling.
- Current methods often rely on volatile refrigerants, posing environmental concerns.
Purpose of the Study:
- To investigate dialkylammonium halides as novel materials for barocaloric applications.
- To understand the structural factors driving barocaloric effects in these organic salts.
Main Methods:
- High-pressure calorimetry
- X-ray diffraction
- Raman spectroscopy
- Nanocalorimetry
Main Results:
- Dialkylammonium halides display large (>200 J kg-1 K-1) and tunable barocaloric effects near ambient temperature.
- Significant entropy changes and high pressure sensitivity were observed due to molecular flexibility.
- Thin-film samples demonstrated excellent cyclability under aggressive conditions (>11,000 cycles).
Conclusions:
- Dialkylammonium halides are promising candidates for solid-state cooling technologies.
- Their tunable barocaloric properties and stability make them suitable for practical applications.
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