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El estado de transferencia de carga frente a la disociación del excitón caliente en las células solares mezcladas de
Jiye Lee1, Koen Vandewal, Shane R Yost
1Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Journal of the American Chemical Society
|August 10, 2010
Resumen
La disociación del excitón caliente tiene un impacto mínimo en las células solares de polímero-fullereno. Los estudios muestran que los rendimientos cuánticos internos son similares para los excitones y la excitación directa de transferencia de carga, lo que sugiere que los procesos calientes no son significativos.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- La energía fotovoltaica es fotovoltaica.
- Química Física es la química física.
Sus antecedentes:
- Las células solares de polímero-fullereno son una tecnología clave para la energía renovable.
- La disociación del excitón es un paso crítico en la conversión de la luz en electricidad.
- La disociación del excitón caliente es un mecanismo propuesto para la generación eficiente de carga.
Objetivo del estudio:
- Para investigar el papel de la disociación del excitón caliente en las células solares arquetípicas de polímero y fullereno.
- Para determinar si los procesos en caliente contribuyen significativamente a la fotogeneración de la portadora.
- Para comparar la eficiencia de la disociación del excitón caliente con la excitación directa de transferencia de carga.
Principales métodos:
- Análisis experimental de dos células solares arquetípicas de mezcla de polímero y fullereno.
- Medición de los rendimientos cuánticos internos para la fotogeneración de la portadora.
- Análisis de la dependencia de temperatura de las características de tensión-corriente.
Principales resultados:
- Se encontró que los rendimientos cuánticos internos eran similares tanto para los excitones como para la excitación del estado de transferencia de carga directa.
- La dependencia de temperatura de las características de tensión-corriente indicó un impacto insignificante de la disociación del excitón caliente.
- La disociación del excitón caliente no parece ser una vía dominante para la generación de carga en estos sistemas.
Conclusiones:
- La importancia de la disociación del excitón caliente en las células solares de polímero-fullereno es insignificante.
- La generación de carga se produce principalmente a través de vías establecidas, no por la disociación del excitón caliente.
- Puede ser necesario realizar más investigaciones para explorar mecanismos o sistemas de materiales alternativos.
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