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Control estérico de la interfaz donante / receptor: implicaciones en la generación de carga fotovoltaica orgánica
Thomas W Holcombe1, Joseph E Norton, Jonathan Rivnay
1Department of Chemistry, University of California Berkeley, Berkeley, California 94720-1460, USA.
Journal of the American Chemical Society
|June 22, 2011
Resumen
Los investigadores mejoraron el rendimiento del dispositivo fotovoltaico orgánico (OPV) mediante la sintonización de sustitutos de polímeros. Esta modificación mejoró la separación de cargas, lo que condujo a una mayor generación de fotocorriente e impulsó la eficiencia de OPV.
Área de la Ciencia:
- La electrónica orgánica es la electrónica orgánica.
- Ciencia de los materiales ciencia de los materiales.
- La energía fotovoltaica es fotovoltaica.
Sus antecedentes:
- El rendimiento del dispositivo fotovoltaico orgánico (OPV) a menudo está limitado por bajas densidades de corriente de cortocircuito.
- La mejora de la transferencia de carga y la separación de excitones es crucial para el avance de la tecnología OPV.
Objetivo del estudio:
- Para investigar cómo el control estérico de la interfaz de separación de carga impacta el rendimiento de OPV.
- Mejorar la generación de fotocorriente en dispositivos OPV a través del diseño molecular.
Principales métodos:
- Modelado computacional para comprender los estados de transferencia de carga.
- Técnicas espectroscópicas para analizar los niveles de energía.
- Química sintética para modificar las columnas vertebrales de polímeros con sustituyentes específicos.
Principales resultados:
- La introducción de sustitutos de octilfenilo en las columnas vertebrales de polímeros aumenta la energía de los estados de transferencia de carga.
- Este aumento de energía reduce la barrera para la separación de cargas, mejorando la fotocorriente.
- Se estableció una relación estructura-propiedad que vincula la estructura del polímero con la eficiencia del dispositivo.
Conclusiones:
- El control estérico de la interfaz es una estrategia viable para mejorar el rendimiento del OPV.
- Este enfoque es particularmente beneficioso para los OPV no fullerenos, abordando sus limitaciones de separación de excitones.
- La adaptación de los sustitutos de polímeros ofrece un camino hacia las células solares orgánicas de mayor eficiencia.
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