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Fotoswitching reversible de la aniquilación triple-triple de la conversión hacia arriba utilizando interruptores

Xiaoneng Cui¹, Jianzhang Zhao, Yuhan Zhou

¹State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology , E-208 West Campus, 2 Ling-Gong Road, Dalian 116024, P. R. China.

Journal of the American Chemical Society

|June 18, 2014

Resumen

Se logró la conversión de aniquilación triple-triple con fotointercambio reversible (TTA UC) utilizando derivados de dietienilethene. El proceso se puede apagar y encender utilizando longitudes de onda de luz específicas, con DTE de forma cerrada que domina los procesos de apagado.

Área de la Ciencia:

La fotoquímica es la fotoquímica.
La fotónica molecular es la fotónica molecular.
Electrónica orgánica y electrónica orgánica.

Sus antecedentes:

La conversión ascendente de aniquilación triplet-tripleta (TTA UC) es un proceso crucial para la recolección y detección de luz.
Los derivados del dietienileteno (DTE) ofrecen propiedades fotocrómicas, lo que permite la conmutación molecular controlada por la luz.
Los tintes corporales y el perileno son efectivos fotosensibilizadores triplet y aceptores, respectivamente.

Objetivo del estudio:

Para demostrar el fotoswitching reversible de TTA UC utilizando derivados de DTE.
Para investigar el mecanismo de fotoswitching en un sistema DTE-Bodipy-perileno.
Para identificar las vías de apagado dominantes responsables de apagar el proceso TTA UC.

Principales métodos:

Síntesis de los derivados de DTE, 2,6-diiodoBodipy y perileno.
Absorción transitoria con resolución temporal y espectroscopia de fluorescencia.
Espectroscopia de absorción de diferencias transitorias con resolución de tiempo de nanosegundos.

Principales resultados:

Se demostró con éxito el fotoswitching reversible de la TTA UC.
El DTE de forma abierta no afectó a TTA UC, pero el DTE de forma cerrada lo apagó tras la irradiación de 254 nm.
La irradiación de luz visible restauró el proceso de TTA UC.
El DTE de forma cerrada se confirmó como la especie de apagado dominante para el estado excitado del tríplete de perileno.

Conclusiones:

Los derivados DTE fotocrómicos pueden controlar eficazmente los procesos TTA UC.
El mecanismo de conmutación implica el apagado de los estados excitados triplet por el DTE de forma cerrada.
Esto proporciona una vía para el desarrollo de sistemas de conversión ascendente direccionables a la luz.

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