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Integrating a Triplet-triplet Annihilation Up-conversion System to Enhance Dye-sensitized Solar Cell Response to Sub-bandgap Light
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Ingeniería molecular de cromóforos para permitir la conversión ascendente de aniquilación de tripletes
Kealan J Fallon1, Emily M Churchill1, Samuel N Sanders2
1Department of Chemistry, Columbia University, New York, New York 10027, United States.
Journal of the American Chemical Society
|November 11, 2020
Resumen
La ingeniería molecular aumenta significativamente los rendimientos de conversión ascendente de aniquilación triple-triple (TTA-UC) al optimizar las energías de estado excitado. Este avance mejora la eficiencia de conversión de luz para aplicaciones como la recolección de energía solar.
Área de la Ciencia:
- Procesos fotofísicos
- Cromóforos orgánicos
- Conversión de energía
Sus antecedentes:
- La conversión ascendente por aniquilación de tripletes (TTA-UC) convierte la luz de baja energía en fotones de alta energía.
- TTA-UC es crucial para la energía solar, la fotoquímica y la optogenética.
- Los rendimientos dependen de las energías de los estados excitados singlet y triplet.
Objetivo del estudio:
- Mejorar el rendimiento cuántico de TTA-UC a través de la ingeniería molecular.
- Para mejorar la cinética de aniquilación triplet-triplet y el decaimiento radiativo del excitón singlet.
- Lograr sistemas TTA-UC de alta eficiencia con emisión de rojo.
Principales métodos:
- Ingeniería molecular de cromóforos orgánicos aromáticos.
- Adaptación selectiva de las energías de estado excitado singlet y triplet más bajas.
- Optimización de la vía de aniquilación triple y triple y decaimiento radiativo.
Principales resultados:
- Se obtienen mejoras de hasta 40 veces en el rendimiento cuántico TTA-UC.
- Se observó una aniquilación triple-triple mejorada y una desintegración radiativa.
- Se obtienen altos rendimientos de conversión hacia arriba con emisión roja y estabilidad química.
Conclusiones:
- La ingeniería molecular ofrece una estrategia general y efectiva para la mejora de la TTA-UC.
- Optimizar las energías de estado excitado es clave para maximizar la eficiencia de TTA-UC.
- La estrategia desarrollada da lugar a sistemas TTA-UC de emisión roja altamente eficientes y estables.
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