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Ajuste de la fluorescencia y la transferencia de carga intramolecular de los derivados dipolares y cuadrupolares de

Yogajivan Rout¹, Chiara Montanari², Erika Pasciucco²

¹Department of Chemistry, Indian Institute of Technology, Indore 453552, India.

Journal of the American Chemical Society

|June 23, 2021

Resumen

La modulación de la oxidación del azufre en los sistemas de fenotiazina-naftalimida mejora las propiedades ópticas. La funcionalización de oxígeno aumenta la fluorescencia para los OLED, mientras que las versiones sin oxígeno ayudan a la fotovoltaica orgánica.

Área de la Ciencia:

Química orgánica
Ciencias de los materiales
La fotofísica

Sus antecedentes:

Los sistemas push-pull basados en naftalimida y fenotiazina son cruciales para las aplicaciones optoelectrónicas.
El ajuste de las propiedades electrónicas a través de la modificación estructural es clave para optimizar el rendimiento del material.

Objetivo del estudio:

Diseñar y sintetizar nuevos sistemas de empuje y tracción de fenotiazina-naftalimida con estados de oxidación de azufre modulados.
Investigar el impacto de la oxidación del azufre en las propiedades espectrales, fotofísicas y electroquímicas.
Explorar las relaciones estructura-propiedad para aplicaciones optoelectrónicas a medida.

Principales métodos:

Reacción de acoplamiento cruzado de Sonogashira catalizada por Pd para la síntesis.
Espectroscopia de absorción y emisión en estado estacionario.
Voltametría cíclica y cálculos mecánicos cuánticos.
Espectroscopia ultrarrápida (absorción transitoria, conversión de la fluorescencia hacia arriba).

Principales resultados:

La funcionalización de oxígeno mejora significativamente las propiedades ópticas, incluida la eficiencia de absorción y fluorescencia.
La fenotiazina es un donante de electrones más fuerte que sus formas oxidadas; la naftalimida actúa como un aceptor fuerte.
Los compuestos oxigenados forman estados de transferencia de carga intramolecular plana (PICT), lo que lleva a una alta fluorescencia.
Los compuestos libres de oxígeno forman estados de transferencia de carga intramolecular retorcida (TICT), apagando la fluorescencia.

Conclusiones:

La funcionalización del oxígeno es una estrategia eficaz para ajustar la fotofísica de los materiales basados en fenotiazina.
Los compuestos altamente fluorescentes oxigenados son adecuados para diodos orgánicos emisores de luz (OLED).
Los sistemas libres de oxígeno con transferencia de carga fotoinducida eficiente son prometedores para la energía fotovoltaica orgánica (OPV).

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