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Descriptor mixto de entalpia y entropía para el diseño racional de materiales sintetizables de alta entropía en

Dibyendu Dey¹, Liangbo Liang², Liping Yu^1,3

¹Department of Physics and Astronomy, University of Maine, Orono, Maine 04469, USA.

Journal of the American Chemical Society

|February 14, 2024

Resumen

Un nuevo descriptor predice de manera eficiente los materiales sintetizables de alta entropía (HEM). Este método utiliza factores de entalpía y entropía para identificar nuevos HEM para diversas aplicaciones, acelerando el descubrimiento de materiales.

Área de la Ciencia:

Ciencias de los materiales
Ciencias de los materiales computacionales
Química del estado sólido

Sus antecedentes:

Los materiales de alta entropía (HEM) ofrecen un gran potencial para el diseño de materiales funcionales debido a su amplio espacio de composición.
La identificación de HEM estables y sintetizables y el establecimiento de reglas de diseño fiables siguen siendo desafíos importantes en el campo.

Objetivo del estudio:

Desarrollar un descriptor altamente eficiente y robusto para predecir materiales sintetizables de alta entropía (HEM) en amplios espacios químicos.
Permitir el cribado de alto rendimiento de los HEM utilizando cálculos basados en los primeros principios.

Principales métodos:

Introducción de un descriptor mixto de entalpia y entropía (MEED) basado en la entalpia de formación relativa y el espectro de energía de formación de puntos de defecto.
Aplicación de MEED a los carburos de sal de roca en 3D y a los sulfuros en capas en 2D para validar su capacidad predictiva.

Principales resultados:

El MEED identificó con éxito todos los HEM experimentalmente reportados en los sistemas de materiales estudiados.
Se estableció un criterio de corte específico del sistema para evaluar la sintetizabilidad del HEM.
Se predijeron decenas de nuevos carburos de alta entropía y sulfuros de alta entropía 2D.

Conclusiones:

El MEED proporciona un enfoque eficiente y sólido para predecir los HEM sintetizables.
Los nuevos HEM identificados muestran potencial para aplicaciones en recubrimientos aeroespaciales, conversión/almacenamiento de energía y electrónica flexible.

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