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Permitir la homociralidad y la estabilidad hidrotermal en cristales porosos basados en Zn4
Xiang Zhao1,2, Huajun Yang1, Edward T Nguyen1
1Department of Chemistry and Biochemistry , California State University , Long Beach , California 90840 , United States.
Journal of the American Chemical Society
|October 24, 2018
Resumen
Dos nuevos materiales porosos, CPM-300 y CPM-301, exhiben estructuras únicas y una alta estabilidad. Los pequeños grupos metilo en los ligandos quirales protegen los grupos de zinc, lo que permite aplicaciones en condiciones adversas.
Área de la Ciencia:
- Ciencias de los materiales
- Química
- Nanotecnología
Sus antecedentes:
- El grupo [Zn4O]6+ típicamente forma la topología MOF-5 con ligandos dicarboxilados.
- El control de la topología y la estabilidad de las estructuras metal-orgánicas (MOF) es crucial para sus aplicaciones.
Objetivo del estudio:
- Para investigar el comportamiento topológico y químico de los grupos [Zn4O]6+ en nuevos materiales.
- Desarrollar nuevos materiales porosos homoquirales y hidrotermalmente estables.
Principales métodos:
- Síntesis de dos nuevos materiales, CPM-300 y CPM-301, utilizando un ligando dicarboxilato quiral.
- Caracterización estructural de los materiales.
- Evaluación de la estabilidad hidrotermal y térmica.
Principales resultados:
- El CPM-300 tiene [Zn4O]6+ grupos que forman un marco de tipo MIL-88/MOF-235.
- CPM-301 exhibe la topología MOF-5 con grupos alternados de [Zn4O]6+ y [Zn9(btz)126+.
- Ambos materiales son homoquirales, hidrotermalmente estables en agua hirviendo y alcohol, y térmicamente estables por encima de 440 °C.
Conclusiones:
- Los pequeños grupos de metilo en el ligando quiral protegen eficazmente los grupos [Zn4O]6+ de la degradación del agua a altas temperaturas.
- Estos hallazgos presentan una plataforma prometedora para crear materiales porosos robustos y homoquirales.
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