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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
Transferencia eficiente de electrones y regeneración del sensibilizador en células solares estables pi-extendidas
Sophie Wenger1, Pierre-Antoine Bouit, Qianli Chen
1Laboratory of Photonics and Interfaces, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Federale de Lausanne (EPFL), Station 6, CH-1015 Lausanne, Switzerland.
Journal of the American Chemical Society
|March 24, 2010
Resumen
Los sensibilizadores orgánicos libres de metales son cruciales para las células solares sensibilizadas con tintes. Los nuevos derivados del tetratiofulvaleno demuestran una regeneración eficiente, permitiendo dispositivos fotovoltaicos funcionales incluso con una pequeña fuerza impulsora de regeneración.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- La electroquímica es electroquímica.
- La energía fotovoltaica es fotovoltaica.
Sus antecedentes:
- Los sensibilizadores orgánicos libres de metales son esenciales para el avance de la tecnología de células solares sensibilizadas por colorante (DSSC).
- Lograr una conversión fotovoltaica eficiente requiere una cuidadosa consideración de las propiedades del sensibilizador y su interacción con los mediadores redox.
Objetivo del estudio:
- Desarrollar y caracterizar nuevos derivados estables de tetratiofulvaleno (TTF) como sensibilizantes orgánicos libres de metales para las DSSC.
- Investigar las propiedades electroquímicas y cinéticas de estos sensibilizadores TTF y su eficiencia de regeneración.
Principales métodos:
- Síntesis y caracterización de nuevos derivados del tetratiofulvaleno.
- Fabricación de dispositivos fotovoltaicos utilizando películas mesoporosas de TiO2 y sensibilizadores de TTF.
- Espectroscopia con resolución de tiempo para estudiar la cinética de regeneración de sensibilizadores foto-oxidados por un mediador redox yoduro/tri-yoduro.
Principales resultados:
- Se logró una exitosa conversión fotovoltaica con los nuevos sensibilizadores orgánicos basados en TTF.
- Se observó una regeneración altamente eficiente de los sensibilizadores de TTF fotooxidados, incluso con una fuerza impulsora de regeneración tan baja como aproximadamente 150 mV.
- El estudio demostró que los sensibilizadores con una pequeña fuerza motriz pueden operar de manera efectiva en DSSCs.
Conclusiones:
- Los nuevos derivados del tetratiofulvaleno representan una clase prometedora de sensibilizantes orgánicos libres de metales para las células solares sensibilizadas con tintes.
- Se puede lograr una regeneración eficiente de los sensibilizadores con una fuerza motriz mínima, ofreciendo una estrategia para reducir las pérdidas de fotovoltaica.
- Este trabajo proporciona una prueba de concepto crucial para el desarrollo de DSSC de alto rendimiento con una mejor alineación energética.
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