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La fisión singular intramolecular cuantitativa en las bipentacenas
Samuel N Sanders1, Elango Kumarasamy1, Andrew B Pun1
1†Department of Chemistry, Columbia University, New York, New York 10027, United States.
Journal of the American Chemical Society
|June 24, 2015
Resumen
La fisión de singlet (SF) en bipentacenos logra altos rendimientos de triplet en soluciones diluidas, lo que demuestra que la SF intramolecular es una propiedad molecular intrínseca. Este avance podría aumentar la eficiencia de las células solares más allá de los límites actuales.
Área de la Ciencia:
- La fotofísica y la fotoquímica.
- Ciencia de los materiales Ciencia de los materiales.
- Tecnologías de energía renovable Tecnologías de energía renovable.
Sus antecedentes:
- La fisión singlet (SF) puede aumentar teóricamente la eficiencia de las células solares de una sola unión del 33% al 44%.
- Anteriormente, los altos rendimientos de SF se limitaban a sólidos cristalinos o agregados de oligoaceno.
- El SF eficiente en soluciones diluidas sigue siendo un desafío importante.
Objetivo del estudio:
- Para demostrar y cuantificar la fisión de singleta intramolecular (iSF) en las moléculas de bipentaceno.
- Investigar el papel de la estructura molecular y el acoplamiento electrónico en iSF.
- Explorar el potencial de iSF para mejorar la conversión de energía solar.
Principales métodos:
- La espectroscopia de absorción transitoria es una espectroscopia de absorción transitoria.
- Espectroscopia de fotoluminiscencia ultrarrápida con espectroscopia de la fotoluminiscencia ultrarrápida.
- Estudios de fotosensibilización de triplet en estudios de fotosensibilización de triplet.
Principales resultados:
- Se lograron rendimientos triplet cercanos al 200% por fotón absorbido en bipentacenos a través de iSF.
- Se ha demostrado que la iSF se produce en soluciones diluidas, independientemente de las interacciones intermoleculares.
- La vida útil correlacionada de los pares triplet (0,5 270 ns) con el acoplamiento electrónico entre las unidades de pentaceno.
Conclusiones:
- La fisión de singlet intramolecular es una propiedad intrínseca de los bipentacenos, controlable por diseño molecular.
- iSF en solución ofrece una vía viable para superar las limitaciones de SF en dispositivos de estado sólido.
- Este trabajo allana el camino para el desarrollo de celdas solares de próxima generación con una eficiencia significativamente mejorada.
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