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Diseño de vértices desimetrizados para la síntesis de marcos orgánicos covalentes con estructuras porosas
Youlong Zhu1, Shun Wan2, Yinghua Jin1
1Department of Chemistry and Biochemistry, University of Colorado , Boulder, Colorado 80309, United States.
Journal of the American Chemical Society
|October 20, 2015
Resumen
Se sintetizaron dos nuevos marcos orgánicos covalentes 2D (COF) con estructuras de doble poro únicas. Esta investigación ofrece nuevas vías para crear materiales porosos avanzados con propiedades a medida.
Área de la Ciencia:
- Ciencias de los materiales
- Química de los polímeros
- Nanotecnología
Sus antecedentes:
- Las estructuras orgánicas covalentes (COF) son polímeros porosos cristalinos con estructuras sintonizables.
- El diseño de FOC con arquitecturas complejas de poros sigue siendo un desafío significativo.
- Las estructuras de poros heterogéneos son deseables para aplicaciones de separación y catalización avanzadas.
Objetivo del estudio:
- Para sintetizar nuevos COF 2D con estructuras de poro periódicamente heterogéneas.
- Investigar las características estructurales y las propiedades de estos nuevos COF.
- Demostrar una estrategia de diseño racional para crear polímeros porosos ordenados.
Principales métodos:
- Estrategia de diseño de vértices desimetrizados para la síntesis de monómeros.
- Reacciones de condensación asistida por solvoterma y microondas para la formación de COF.
- Difracción de rayos X en polvo (PXRD), adsorción de gases, RMN en estado sólido, FT-IR, SEM, TEM y simulaciones teóricas para la caracterización.
Principales resultados:
- Síntesis exitosa de dos COFs 2D cristalinos, el HP-COF-1 y el HP-COF-2.
- Confirmación de estructuras de poro hexagonales duales y distintas en ambos COF mediante PXRD y modelado.
- Alta superficie específica y datos de caracterización que confirman la integridad y porosidad del marco.
Conclusiones:
- Una nueva estrategia de diseño de vértices desimetrizados permite la síntesis de COF con estructuras de poros heterogéneos.
- Los HP-COF-1 y HP-COF-2 sintetizados exhiben características únicas de doble poro.
- Este enfoque abre nuevas vías para el diseño racional y la síntesis de polímeros porosos ordenados avanzados.
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