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La sintonización de las energías de transferencia de carga en el centro de reacción imita a través de la
Fabian Spänig1, Christian Kovacs, Frank Hauke
1Department of Chemistry and Pharmacy and Interdisciplinary Center of Molecular Materials, Friedrich-Alexander Universität Erlangen Nürnberg, Egerlandstrasse 3, 91058 Erlangen, Germany.
Journal of the American Chemical Society
|May 23, 2009
Resumen
Los investigadores crearon aductos de fullereno (C60) con unidades de ferroceno y porfirina para aumentar la energía del estado del par de iones radicales. Estas moléculas almacenan energía significativa brevemente, influenciadas por la estructura y el disolvente, pero la estabilización sigue siendo un desafío.
Área de la Ciencia:
- Química supramolecular de las moléculas.
- La fotoquímica es la fotoquímica.
- La electroquímica es electroquímica.
Sus antecedentes:
- Los fullerenos (C60) son versátiles bloques de construcción para materiales avanzados.
- El control de la transferencia de carga en los sistemas moleculares es crucial para las aplicaciones de energía.
- Los estados de par de iones radicales ofrecen potencial para el almacenamiento de energía.
Objetivo del estudio:
- Para sintetizar y caracterizar nuevos aductos C60 con unidades de ferroceno y porfirina.
- Investigar los factores que influyen en la transferencia de carga y el almacenamiento de energía en estos sistemas.
- Para explorar el potencial de estas moléculas para crear estados de par de iones radicales de larga vida.
Principales métodos:
- Síntesis de mono- y hexakis-adductos de C60 con ferroceno y porfirina.
- Análisis electroquímico para determinar los potenciales redox y los niveles de energía.
- Estudios fotofísicos (por ejemplo, espectroscopia de absorción transitoria) para sondear la dinámica de transferencia de carga.
- Variación sistemática de la funcionalización C60, la fuerza del donante y la polaridad del disolvente.
Principales resultados:
- Se lograron patrones de adición T (h) -simétricos para los aductos C60.
- Se descubrió que los eventos de transferencia de carga dependen de la funcionalidad de C60, la fuerza del donante, la energía del estado excitado y la polaridad del disolvente.
- Se identificaron unidades de porfirina como clave para conducir estados de pares de iones radicales separados espacialmente.
- Un sistema ZnP-C60-(Fc) 10 almacenado ~ 1.7 eV en un estado de par de iones radicales de vida de un nanosegundo en el benzonitrilo y el DMF.
Conclusiones:
- Novel C60 adducts demuestran propiedades electrónicas sintonizables para la transferencia de carga.
- Los sistemas C60 que contienen porfirina son prometedores para aplicaciones de almacenamiento de energía.
- Los enlaces flexibles facilitan la transferencia de carga a través del espacio, pero limitan la estabilización del estado del par de iones radicales más allá de la escala de tiempo del nanosegundo.
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