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Integrating a Triplet-triplet Annihilation Up-conversion System to Enhance Dye-sensitized Solar Cell Response to Sub-bandgap Light
Published on: September 12, 2014
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Aproximándose al límite de espín estadístico en la conversión de fotones visibles a ultravioleta
Axel Olesund1, Jessica Johnsson1, Fredrik Edhborg1
1Department of Chemistry and Chemical Engineering, Chalmers University of Technology, 41296 Gothenburg, Sweden.
Journal of the American Chemical Society
|February 17, 2022
Resumen
Este estudio logró un rendimiento cuántico récord del 16,8% para la conversión ascendente del fotón de aniquilación triple-triple de visible a ultravioleta (UV), acercándose al límite teórico. Este avance avanza las aplicaciones de TTA-UC en áreas como la energía solar y la fotoquímica.
Área de la Ciencia:
- La fotoquímica
- Ciencias de los materiales
- Química Física
Sus antecedentes:
- La conversión de fotones de aniquilación triplet-tripleta (TTA-UC) convierte fotones de baja energía en fotones de mayor energía, crucial para aplicaciones en biología y energía solar.
- Los sistemas TTA-UC existentes de visible a ultravioleta (UV) luchan por lograr altos rendimientos cuánticos, generalmente por debajo del 10%.
Objetivo del estudio:
- Investigar nuevas moléculas aniquiladoras para el TTA-UC visible-UV eficiente.
- Para explorar el rendimiento de TTA-UC utilizando el sensibilizador 2,3,5,6-tetra(9H-carbazol-9-yl) benzonitrilo (4CzBN).
Principales métodos:
- Detección de seis moléculas de aniquiladoras diferentes combinadas con el sensibilizador 4CzBN.
- Medición de los rendimientos cuánticos internos del TTA-UC (ΦUC,g).
- Desarrollo de un nuevo método de determinación de las constantes de velocidad TTA utilizando la resolución temporal de las emisiones.
Principales resultados:
- Se logró un rendimiento cuántico interno TTA-UC del 16,8% para el 1,4-bis (triisopropilsil) etinileftaleno, acercándose al límite estadístico de espín del 20%.
- Se ha demostrado un valor elevado de ΦUC,g por encima del 12% para otros tres aniquiladores, incluido el nuevo uso del 2,5-difenilfurano.
- Se ha aplicado con éxito un método simplificado para la determinación de la constante de velocidad TTA.
Conclusiones:
- Este trabajo establece un nuevo punto de referencia para la eficiencia de TTA-UC visible a UV.
- Los hallazgos allanan el camino para el desarrollo de sistemas TTA-UC altamente eficientes para reacciones fotoquímicas de alta energía y conversión avanzada de energía solar.
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