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Un marco metálico-orgánico excepcionalmente estable construido a partir de poliedros metálico-orgánicos basados en
Jerika A Chiong1, Jie Zhu1, Jake B Bailey1
1Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093, United States.
Journal of the American Chemical Society
|April 1, 2020
Resumen
Los investigadores desarrollaron un marco orgánico metálico estable (MOF), Fe-HAF-1, utilizando ligandos de hidroxamato. Este material exhibe una notable estabilidad química y adsorbe selectivamente especies cargadas, lo que permite una separación eficiente de tintes y otras moléculas.
Área de la Ciencia:
- Ciencias de los materiales
- Química supramolecular
- Química de coordinación
Sus antecedentes:
- Las estructuras metálicas orgánicas (MOF) ofrecen propiedades ajustables para diversas aplicaciones.
- El desarrollo de MOF con una estabilidad química y hídrica excepcional sigue siendo un desafío importante.
- La química de coordinación basada en el hidroxamato proporciona una ruta hacia materiales de marco robustos.
Objetivo del estudio:
- Diseñar y sintetizar racionalmente un marco metálico orgánico (MOF) estable en agua utilizando poliedros a base de hidroxamato.
- Investigar la estabilidad y las propiedades del nuevo Fe-HAF-1 MOF.
- Explorar el potencial del Fe-HAF-1 para la adsorción y separación selectiva de iones.
Principales métodos:
- Diseño y síntesis racionales del Fe-HAF-1 MOF.
- Caracterización de la estructura y propiedades del Fe-HAF-1.
- Evaluación de la estabilidad química en un amplio rango de pH (1-14) y en álcalis fuertes.
- Investigación de las capacidades de adsorción y separación de iones para especies cargadas y tintes orgánicos.
Principales resultados:
- Síntesis exitosa de un MOF estable en agua, Fe-HAF-1, con nodos mononucleares Fe3+ y ligandos de hidroxamato.
- El Fe-HAF-1 exhibe una estabilidad excepcional en diversos disolventes orgánicos y acuosos, incluido el 5 M NaOH.
- Carga negativa inesperada en los cristales de Fe-HAF-1 por encima del pH 4, atribuida a defectos de cristalización.
- Se ha demostrado la adsorción selectiva de iones cargados positivamente y la separación selectiva del tamaño de los tintes orgánicos.
Conclusiones:
- El Fe-HAF-1 representa un nuevo MOF a base de quelato con una notable estabilidad y propiedades aniónicas únicas.
- La carga inducida por el defecto del marco permite una separación eficiente de las especies cargadas.
- El Fe-HAF-1 amplía la biblioteca de MOF basados en hidroxamato y ofrece una plataforma prometedora para las tecnologías de separación.
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