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Efectos barocalóricos en las sales de haluro de dialquilamonio
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
Resumen
Los haluros de dialquilamonio exhiben efectos barocalóricos significativos para un enfriamiento eficiente en estado sólido. Estas sales orgánicas muestran grandes cambios térmicos reversibles cerca de la temperatura ambiente, ofreciendo una alternativa sostenible a los refrigerantes tradicionales.
Área de la Ciencia:
- Ciencias de los materiales
- La termodinámica
- Física del estado sólido
Sus antecedentes:
- Los efectos barocalóricos ofrecen potencial para la calefacción y refrigeración energéticamente eficientes.
- Los métodos actuales a menudo se basan en refrigerantes volátiles, lo que plantea preocupaciones ambientales.
Objetivo del estudio:
- Investigar los haluros de dialquilamonio como nuevos materiales para aplicaciones barocalóricas.
- Comprender los factores estructurales que impulsan los efectos barocalóricos en estas sales orgánicas.
Principales métodos:
- Calorimetría de alta presión
- Difracción de rayos X
- Espectroscopia de Raman
- La nanocalorimetría
Principales resultados:
- Los haluros de dialquilamonio muestran efectos barocalóricos grandes (> 200 J kg-1 K-1) y ajustables cerca de la temperatura ambiente.
- Se observaron cambios significativos en la entropía y una alta sensibilidad a la presión debido a la flexibilidad molecular.
- Las muestras de película delgada demostraron una excelente ciclabilidad en condiciones agresivas (> 11.000 ciclos).
Conclusiones:
- Los haluros de dialquilamonio son candidatos prometedores para las tecnologías de refrigeración en estado sólido.
- Sus propiedades barocalóricas ajustables y su estabilidad los hacen adecuados para aplicaciones prácticas.
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