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Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry
Published on: October 18, 2019
Acoplamiento de olefinas a monocapas mixtas de metilo / tienila en las superficies de Si ()
Leslie E O'Leary1, Michael J Rose, Tina X Ding
1Beckman Institute and Kavli Nanosciences Institute, Division of Chemistry and Chemical Engineering, 210 Noyes Laboratory, California Institute of Technology, Pasadena, California 91125, USA.
Journal of the American Chemical Society
|June 28, 2013
Resumen
Los investigadores utilizaron la reacción de Heck para funcionalizar superficies de silicio con moléculas orgánicas, reduciendo significativamente la velocidad de recombinación de la superficie. Este método permite un acoplamiento electrónico robusto para fotoelectrodos de silicio avanzados.
Área de la Ciencia:
- Química de las superficies.
- Ciencia de los materiales Ciencia de los materiales.
- Electrónica orgánica y electrónica orgánica.
Sus antecedentes:
- Las superficies de silicio (Si) son cruciales para los dispositivos electrónicos, pero son propensas a la recombinación superficial.
- La funcionalización de las superficies de Si puede mejorar sus propiedades electrónicas y permitir nuevas aplicaciones.
Objetivo del estudio:
- Desarrollar un método para la fijación de moléculas pequeñas a las superficies de Si{111} utilizando la reacción de Heck.
- Para investigar el impacto de la funcionalización de la superficie en la transferencia de carga y la velocidad de recombinación de la superficie.
- Para crear enlaces robustos para los fotoelectrodos de silicio.
Principales métodos:
- Funcionalización de Si(111) con monocapas mixtas de metilo y tienila.
- Acoplamiento hexagonal de las olefinas a la superficie de Si funcionalizada.
- Bromado y activación catalizada por paladio de las superficies de haluro de arilo.
- Acoplamiento de varios sustratos orgánicos (4-fluorostireno, vinilferroceno, estero dimetilo de protoporfirina IX).
Principales resultados:
- Las superficies mezcladas CH3 / SC4H3-Si111) mostraron una velocidad de recombinación superficial significativamente reducida (S = 27 ± 9 cm s(-1)) en comparación con las superficies de solo tienila (S = 670 ± 190 cm s(-1)).
- El acoplamiento exitoso del vinilferroceno demostró una fácil transferencia de electrones y un vínculo superficial robusto.
- Las superficies finales acopladas a Heck mantuvieron un bajo valor de S (70 cm s(-1)), lo que indica una alta calidad.
Conclusiones:
- La reacción de Heck proporciona una ruta versátil para crear superficies de silicio funcionalizadas con propiedades electrónicas mejoradas.
- Este enfoque sintético de varios pasos permite la unión robusta de pequeñas moléculas a los fotoelectrodos de silicio.
- El método desarrollado es prometedor para la fabricación de dispositivos electrónicos y optoelectrónicos basados en silicio de alto rendimiento.
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