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Determining Surface Areas and Pore Volumes of Metal-Organic Frameworks
Published on: March 8, 2024
Funcionalización en sólidos porosos flexibles: efectos sobre la apertura de los poros y las interacciones
Thomas Devic1, Patricia Horcajada, Christian Serre
1Institut Lavoisier, UMR CNRS 8180, Université de Versailles Saint-Quentin-en-Yvelines, 45 avenue des Etats-Unis, 78035 Versailles cedex, France. devic@chimie.uvsq.fr
Journal of the American Chemical Society
|December 30, 2009
Resumen
Los investigadores sintetizaron marcos metálico-orgánicos funcionalizados MIL-53 (Fe) con superficies de poros modificadas. La geometría de la abertura de los poros está vinculada a las interacciones del marco, no al tamaño del sustituyente, con una variante que muestra porosidad accesible.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Química Química es la química.
- Nanotecnología La nanotecnología es la nanotecnología.
Sus antecedentes:
- Las estructuras metal-orgánicas (MOF) ofrecen propiedades sintonizables para diversas aplicaciones.
- MIL-53 ((Fe) es un MOF flexible con potencial para el almacenamiento y la separación de gases.
- La funcionalidad de los enlaces MOF permite la modificación sistemática de los entornos de los poros.
Objetivo del estudio:
- Para sintetizar y caracterizar a escala de gramos el tereftalato de hierro funcionalizado y flexible MIL-53 ((Fe) sólidos.
- Para investigar el impacto de varios grupos químicos en el marco MIL-53 ((Fe) y las propiedades de los poros.
- Para correlacionar la geometría de la abertura de los poros con las interacciones intraestructurales y los efectos de sustitución.
Principales métodos:
- Síntesis en escala de gramos de materiales funcionalizados MIL-53 ((Fe)).
- Difracción de polvo de rayos X (XRPD) para el análisis estructural.
- Simulaciones moleculares y espectrometría de IR in situ y (57) Fe Mössbauer para la caracterización.
- Análisis termogravimétricos (TGA) para la evaluación de la estabilidad térmica.
Principales resultados:
- Todos los sólidos sintetizados adoptaron una forma de poro estrecho, similar al puro MIL-53 ((Fe), tanto en estado seco como hidratado.
- La geometría de la abertura de los poros está dictada principalmente por las interacciones dentro del marco, no por el obstáculo estérico de los sustituyentes.
- MIL-53 ((Fe) - ((CF)) (3)) (2) demostró porosidad accesible con un área de superficie BET de aproximadamente 100 m ((2) g ((-1).
- La adsorción de líquido indujo comportamientos específicos de apertura de poros influenciados por las interacciones huésped-marco.
Conclusiones:
- La funcionalización sistemática de MIL-53 ((Fe) proporciona control sobre las propiedades de la superficie de los poros.
- Las interacciones intraestructurales son el factor dominante que rige la geometría de los poros en estos MOFs flexibles.
- La diferencia de energía entre las formas de poro estrecho y grande, evaluada por simulación molecular, explica los comportamientos de adsorción observados.
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