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Updated: May 28, 2026
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Microfluidic-based Synthesis of Covalent Organic Frameworks (COFs): A Tool for Continuous Production of COF Fibers and Direct Printing on a Surface
Published on: July 10, 2017
Un marco orgánico covalente 2D con poros de 4,7 nm y una visión de su apilamiento entre capas
Eric L Spitler1, Brian T Koo, Jennifer L Novotney
1Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA.
Journal of the American Chemical Society
|October 22, 2011
Resumen
Los investigadores sintetizaron un nuevo marco orgánico covalente 2D (COF) con poros de tamaño récord para un transporte de carga eficiente. Los cálculos avanzados revelaron un único apilamiento entre capas, que difiere de las típicas estructuras eclipsadas.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Nanotecnología La nanotecnología es la nanotecnología.
- Química orgánica es la química orgánica.
Sus antecedentes:
- Los marcos orgánicos covalentes en capas bidimensionales (2D COFs) ofrecen sistemas ordenados de electrones π beneficiosos para el transporte de excitones y cargas.
- Su porosidad permanente permite una funcionalidad versátil.
- El desarrollo de COF con propiedades estructurales mejoradas es crucial para aplicaciones avanzadas.
Objetivo del estudio:
- Para sintetizar un COF 2D con los poros más grandes reportados hasta la fecha.
- Para preparar el COF tanto en polvo microcristalino como en formas de película delgada orientada verticalmente.
- Para investigar el espaciamiento entre capas y el apilamiento del COF. sintetizado.
Principales métodos:
- Reacción de condensación entre el 2,3,6,7,10,11-hexahidroxitrifenileno (HHTP) y el 4,4'-difenilbutadienebis (ácido borónico) (DPB).
- Preparación de polvo microcristalino y películas delgadas sobre sustratos de grafeno/sílice fundida.
- Dinámica molecular y cálculos de la teoría funcional de la densidad (DFT).
Principales resultados:
- Síntesis exitosa de un COF 2D con poros sin precedentes de gran tamaño.
- Caracterización del COF como un polvo de gran superficie y una película delgada orientada verticalmente.
- El análisis computacional indicó un desplazamiento horizontal de 1.7-1.8 Å entre capas adyacentes, desviándose del apilamiento de AA eclipsado.
Conclusiones:
- El COF 2D sintetizado posee poros excepcionalmente grandes, avanzando en el diseño de COF.
- La preparación del material en forma de película delgada sobre el grafeno abre vías para la integración de dispositivos.
- El desplazamiento entre capas descubierto proporciona nuevos conocimientos sobre el polimorfismo estructural y el empaque de COF.
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