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Síntesis en la superficie de las nanocintas de carbono porosas de las cadenas de polímeros
Maximilian Ammon1, Tim Sander1, Sabine Maier1
1Department of Physics, Friedrich-Alexander-University Erlangen-Nürnberg , Erwin-Rommel-Strasse 1, 91058 Erlangen, Germany.
Journal of the American Chemical Society
|August 19, 2017
Resumen
Los investigadores sintetizaron nanocintas de carbono porosas en superficies de plata mediante el control de la isomerización y la deshidrogenación de la cadena de polímeros. Este método ofrece una nueva ruta para el diseño de materiales de carbono nanoestructurados.
Área de la Ciencia:
- Ciencias de los materiales
- Química de las superficies
- Nanotecnología
Sus antecedentes:
- La síntesis en la superficie permite la fabricación precisa de nanoestructuras.
- El control de la conformación de la cadena de polímero es crucial para el ensamblaje dirigido.
- Los materiales porosos de carbono tienen diversas aplicaciones.
Objetivo del estudio:
- Para demostrar la síntesis en la superficie de las nanocintas de carbono porosas.
- Investigar el papel de la isomerización de la cadena de polímeros en la formación de nanoestructuras.
- Explorar el uso de reacciones con plantillas metálicas para crear nuevos materiales de carbono.
Principales métodos:
- La polimerización en superficie del 1,3,5-tris3-bromofenilbenceno (mTBPB) en Ag111 utilizando el acoplamiento de tipo Ullmann.
- El recocido térmico para inducir la desbrominación, la conmutación conformacional y el enlace transversal de deshidrogenación.
- Microscopía de túnel de barrido a baja temperatura (LT-STM) para estudiar los mecanismos de reacción.
Principales resultados:
- Prochiral mTBPB polimerizado en cadenas y anillos organometálicos en Ag{111).
- Conmutación conformacional de mTBPB, modelado por los átomos de Ag, formación de la cadena dirigida.
- El tratamiento térmico condujo a la vinculación covalente y la formación de nanocintas de carbono porosas.
- La rotación de las unidades de fenileno fue clave para lograr el control estructural.
Conclusiones:
- La síntesis en la superficie proporciona una vía para las nanocintas de carbono porosas.
- La isomerización y la deshidrogenación de polímeros son estrategias efectivas para el diseño de nanoestructuras.
- Las reacciones con plantilla metálica ofrecen un control preciso sobre las nanoestructuras orgánicas cíclicas.
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