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Dímero de tetraceno: una plataforma para la conversión intramolecular hacia abajo y hacia arriba

Yifan Bo¹, Yuxuan Hou², Dominik Thiel¹

¹Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials (ICMM), Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstr. 3, 91058 Erlangen, Germany.

Journal of the American Chemical Society

|August 2, 2023

Resumen

Los investigadores exploraron cómo los dímeros de tetraceno pueden convertir la energía de los fotones utilizando la fisión singleta (SF) y la aniquilación tripleta-tripleta (TTA-UC). Caracterizaron la interacción entre estos procesos y el impacto de la temperatura en su eficiencia.

Área de la Ciencia:

Ciencias de los materiales
La fotoquímica
Energía renovable

Sus antecedentes:

La conversión de energía fotónica es crucial para la eficiencia de las células solares.
La fisión de singlet (SF) y la aniquilación triplet-triple up-conversion (TTA-UC) son dos procesos clave.
El tetraceno presenta un potencial tanto para el SF como para el TTA-UC.

Objetivo del estudio:

Diseñar y caracterizar dímeros de tetraceno con acoplamiento electrónico variable.
Investigar la interacción entre el SF intramolecular y el TTA-UC.
Explorar la fotoexcitación indirecta del TTA-UC y los efectos de la temperatura.

Principales métodos:

Síntesis de dimeros de tetraceno ligados al meta-dietinilefenileno y al 1,3-dietiniledamantilo.
Espectroscopia de absorción y fluorescencia en estado estacionario y con resolución temporal.
Mediciones dependientes de la temperatura y fotoexcitación indirecta mediante Pd-ftalocianina.

Principales resultados:

Dímero de tetraceno diseñado con acoplamiento electrónico distinto para el estudio de la intra-SF y la intra-TTA-UC.
Caracterizó la interacción entre los procesos intramoleculares de SF y TTA-UC.
Se ha demostrado la fotoexcitación indirecta del intra-TTA-UC y se han analizado los efectos térmicos.

Conclusiones:

Los dímeros de tetraceno ofrecen una plataforma para estudiar las vías de conversión de energía de fotones competidores.
Comprender la interacción de SF y TTA-UC es vital para optimizar la recolección de energía solar.
La temperatura influye significativamente en la eficiencia de estos procesos intramoleculares.

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