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Supermolecular-cromóforo-sensibilizado de infrarrojo cercano a fotones visibles conversión hacia arriba conversión
Tanya N Singh-Rachford1, Animesh Nayak, Maria L Muro-Small
1Department of Chemistry and Center for Photochemical Sciences, Bowling Green State University, Bowling Green, Ohio 43403, USA.
Journal of the American Chemical Society
|September 11, 2010
Resumen
Este estudio demuestra la conversión ascendente de fotones del infrarrojo cercano al visible utilizando un sensibilizador de supermolécula de rutenio (II), logrando una ganancia de energía anti-Stokes récord a través de la fotoquímica de aniquilación triple-triple.
Área de la Ciencia:
- La fotoquímica es la fotoquímica.
- Ciencia de los materiales Ciencia de los materiales.
- La espectroscopia es una técnica de espectroscopia.
Sus antecedentes:
- La conversión ascendente de fotones permite generar fotones de mayor energía a partir de fotones de menor energía.
- La aniquilación tripleta-tripleta (TTA) es un mecanismo clave para una eficiente conversión ascendente de fotones.
- El desarrollo de sistemas estables y eficientes de conversión de NIR a visible es crucial para diversas aplicaciones.
Objetivo del estudio:
- Para demostrar y caracterizar la conversión ascendente de fotones de NIR a visible utilizando un nuevo sensibilizador de supermoléculas de rutenio (II).
- Para investigar la fotoquímica subyacente de la aniquilación triple-triple (TTA).
- Para lograr una ganancia de energía anti-Stokes significativa y evaluar la estabilidad del sistema.
Principales métodos:
- Excitación selectiva en el infrarrojo cercano (NIR) a 780 nm.
- Utilizando una supermolécula de rutenio (Pyr) como sensibilizador con PDI o tetraceno.
- Monitoreo de fluorescencia convertida hacia arriba y absorción en estado excitado.
- Determinación de parámetros cinéticos como las constantes de apagado y las constantes de velocidad TTA.
- Medir el rendimiento cuántico y evaluar la fotoestabilidad.
Principales resultados:
- Se logró una sustancial ganancia de energía anti-Stokes (0,70 eV para el PDI, 0,86 eV para el tetraceno).
- Se confirmó la fotoquímica de la aniquilación tripleta-tripleta (TTA) sensibilizada por Pyr(1) RuPZn(2).
- Se obtuvo un cambio anti-Stokes récord de 0.86 eV para TTA sensibilizado.
- Se ha demostrado una excelente fotostabilidad del sistema Pyr{1) RuPZn{2) / PDI durante varias horas.
Conclusiones:
- La supermolécula de rutenio (II) sensibiliza efectivamente el TTA para una eficiente conversión de fotones de NIR a visible.
- El sistema logra un récord de ganancia de energía anti-Stokes, mostrando su potencial.
- La combinación Pyr{1) RuPZn{2) / PDI exhibe una fotoestabilidad notable, adecuada para aplicaciones prácticas.
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