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Cromóforos conjugados de brecha de banda estrecha con longitudes moleculares extendidas
Xiaofeng Liu1, Yanming Sun, Louis A Perez
1Center for Polymers and Organic Solids, University of California, Santa Barbara, California 93106, USA.
Journal of the American Chemical Society
|December 11, 2012
Resumen
La extensión de la longitud molecular en la optoelectrónica orgánica mejora la estabilidad térmica más allá de 200 °C. Esto permite celdas solares de heterounión a granel eficientes con eficiencias de conversión de energía de más del 6% sin aditivos.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Electrónica orgánica y electrónica orgánica.
- La energía fotovoltaica es fotovoltaica.
Sus antecedentes:
- Los dispositivos optoelectrónicos orgánicos requieren materiales con alta estabilidad térmica y transporte de carga eficiente.
- Los cromóforos donante-aceptante son componentes clave en los dispositivos electrónicos orgánicos, que influyen en su rendimiento.
Objetivo del estudio:
- Investigar el impacto de la longitud molecular en los cromóforos donante-aceptante en las propiedades relevantes para la optoelectrónica orgánica.
- Desarrollar nuevos sistemas de brecha de banda estrecha para mejorar el rendimiento del dispositivo.
Principales métodos:
- Síntesis de dos nuevos sistemas cromóforos donante-aceptor de banda estrecha con diferentes longitudes moleculares.
- Fabricación y caracterización de dispositivos de transistor de efecto de campo (FET).
- Fabricación y caracterización de las células solares de heterounión a granel (BHJ).
Principales resultados:
- Los sistemas de mayor peso molecular demostraron una mayor estabilidad térmica, superando los 200 °C en los dispositivos FET.
- Las células solares BHJ fabricadas con estos materiales y PC{61) BM lograron eficiencias de conversión de energía superiores al 6%.
- Se mantuvieron altas eficiencias en varias composiciones de mezclas y sin aditivos de disolventes o recocido post-deposición.
Conclusiones:
- Extender la longitud molecular de los cromóforos donante-aceptante es una estrategia viable para mejorar la estabilidad térmica en dispositivos electrónicos orgánicos.
- Los sistemas de brecha de banda estrecha desarrollados son prometedores para las células solares orgánicas eficientes y estables.
- El rendimiento del dispositivo es robusto, mostrando menos sensibilidad a las condiciones de procesamiento.
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