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Compuesto ferromagnético Eu2SiO4 con un efecto magnetocalórico de campo bajo récord y una excelente conductividad
Zhaojun Mo1, Jiaxin Jiang1, Lu Tian1
1Key Laboratory of Rare Earths, Ganjiang Innovation Academy, Chinese Academy of Sciences, Ganzhou 341119, China.
Journal of the American Chemical Society
|April 16, 2025
Resumen
El silicato de europio (Eu2SiO4) demuestra un efecto magnetocalórico (MCE) récord para la refrigeración magnética criogénica. Este material también exhibe excelentes propiedades térmicas, lo que lo hace ideal para aplicaciones de temperatura de helio líquido.
Área de la Ciencia:
- Ciencias de los materiales
- La termodinámica
- Física de la materia condensada
Sus antecedentes:
- La refrigeración magnética requiere materiales con gran efecto magnetocalórico (MCE) y buenas propiedades térmicas.
- El desarrollo de refrigerantes eficientes para temperaturas de helio líquido es crucial para los avances tecnológicos.
Objetivo del estudio:
- Investigar las propiedades magnetocalóricas y térmicas del ferromagnético Eu2SiO4.
- Evaluar el Eu2SiO4 como refrigerante magnético criogénico potencial.
Principales métodos:
- Las mediciones del cambio de entropía magnética.
- Medidas de la capacidad térmica.
- Mediciones de la conductividad térmica.
Principales resultados:
- Eu2SiO4 exhibe un cambio máximo de entropía magnética (-ΔSMmax) de 21.6 J·kg-1·K-1 a 0-1 T, un nuevo récord para las temperaturas de helio líquido.
- El calor específico alcanza un pico de 107.9 J·kg-1·K-1 cerca de la temperatura del helio líquido.
- La conductividad térmica es de 1,52 W·m-1·K-1 a 4,2 K, comparable a los materiales regenerativos comerciales.
Conclusiones:
- Eu2SiO4 presenta una combinación excepcional de MCE y propiedades térmicas.
- Este compuesto es un material muy prometedor para aplicaciones de refrigeración magnética criogénica.
- La validación experimental confirma su eficacia como refrigerante magnético en el rango de helio líquido.
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