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Control de la brecha de banda en oligómeros conjugados a través de ácidos de Lewis
Gregory C Welch1, Robert Coffin, Jeff Peet
1Center for Polymers and Organic Solids, Department of Chemistry & Biochemistry, University of California, Santa Barbara, California 93106, USA.
Journal of the American Chemical Society
|July 10, 2009
Resumen
Los investigadores desarrollaron un nuevo método para controlar las brechas de banda óptica utilizando una molécula única y ácidos de Lewis. Esta estrategia permite espectros de absorción sintonizables en materiales para aplicaciones electrónicas.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Química orgánica es la química orgánica.
- La fotofísica es la fotofísica.
Sus antecedentes:
- El control de la brecha de banda óptica es crucial para el diseño de materiales avanzados.
- Los semiconductores orgánicos de pequeñas moléculas ofrecen propiedades electrónicas sintonizables.
Objetivo del estudio:
- Demostrar una estrategia simple y efectiva para el control de la brecha de banda óptica.
- Para investigar la interacción entre una nueva molécula aceptor / donante / aceptor y los ácidos de Lewis.
Principales métodos:
- Síntesis de una nueva molécula aceptora/donante/aceptora (1) que incluye dietienolesilole donante y unidades aceptoras de benzo-2,1,3-tiadiazol (BT).
- Adición de cantidades estequiométricas de ácidos de Lewis del grupo 13 de diferentes intensidades a la molécula 1.
- Caracterización mediante espectroscopia UV-Vis, espectroscopia de Resonancia Magnética Nuclear (RMN) y difracción de rayos X.
Principales resultados:
- Formación de adductos de Lewis tras la adición de ácidos de Lewis a la molécula 1.
- Se observaron bandas de absorción de transferencia de carga primaria desplazadas progresivamente hacia el rojo con un aumento de la fuerza del ácido de Lewis.
- Los espectros de absorción de los complejos se acercaron a los de los copolímeros conjugados conocidos.
- La RMN y la difracción de rayos X confirmaron que la molécula 1 se une a dos equivalentes de ácido de Lewis en el nitrógeno de la unidad BT.
Conclusiones:
- El estudio presenta un método fácil para ajustar la brecha de banda óptica de los materiales orgánicos.
- Las interacciones ácido-base de Lewis proporcionan una poderosa herramienta para modificar las propiedades electrónicas y ópticas de las moléculas pequeñas.
- La estrategia desarrollada muestra potencial para aplicaciones en electrónica orgánica y optoelectrónica.
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