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Synthesis and Characterization of Supramolecular Colloids
Published on: April 22, 2016
Generar largas vías supramoleculares con una densidad continua de estados mediante la vinculación física de moléculas
Roozbeh Shokri1, Marie-Agnés Lacour, Thibaut Jarrosson
1Institut de Sciences des Matériaux de Mulhouse IS2M, LRC 7228-CNRS-UHA, 4 rue des frères Lumière, 68093 Mulhouse, France.
Journal of the American Chemical Society
|March 23, 2013
Resumen
Los oligómeros conjugados se autoensamblan en cadenas 1D en el grafeno, formando estructuras enlazadas por extremos. Esto preserva la conjugación de electrones, visualizando potencialmente los agregados J a través de la autoorganización molecular.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Química supramolecular de las moléculas.
- Ciencias de la superficie Ciencias de la superficie.
Sus antecedentes:
- Los oligómeros conjugados son cruciales para la electrónica orgánica.
- Controlar el autoensamblaje en las superficies es clave para la fabricación de dispositivos.
- El grafeno ofrece una plataforma única para la autoorganización molecular.
Objetivo del estudio:
- Para investigar el comportamiento de autoensamblaje de los oligómeros a base de 2,5-dialcoxi-fenileno-tienileno en el grafeno.
- Comprender las propiedades estructurales y electrónicas de las estructuras supramoleculares resultantes.
- Explorar el potencial para extender la conjugación electrónica a través de la autoorganización.
Principales métodos:
- Deposición de oligómeros en el vacío ultraalto (UHV, por sus siglas en inglés).
- Microscopía de túnel de barrido a baja temperatura (LT-STM) para imágenes estructurales.
- Espectroscopia de túnel de barrido (STS) (mapas dI/dV) para las propiedades electrónicas.
Principales resultados:
- Formación de largas estructuras unidimensionales (1D) de tipo cadena supramolecular.
- Observación de la unión de extremos a través de la rotación del anillo de tiofeno que permite el apilamiento pi-pi.
- La densidad electrónica continua de los estados dentro de las cadenas sugiere una conjugación preservada a través de moléculas vinculadas.
Conclusiones:
- El autoensamblaje de estos oligómeros en el grafeno conduce a estructuras 1D ordenadas.
- El end-linking físico puede mantener y potencialmente extender la conjugación de electrones.
- Las estructuras observadas pueden representar una visualización directa de los agregados J.
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