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Una descripción realista de la función de onda portadora de carga en semiconductores de polímero microcristalino
D L Cheung1, D P McMahon, A Troisi
1Department of Chemistry and Centre of Scientific Computing, University of Warwick, CV4 7AL Coventry, UK.
Journal of the American Chemical Society
|July 23, 2009
Resumen
La química computacional revela portadores de carga localizados y trampas de larga vida en los polímeros semiconductores de poli 3-hexiltiofeno (P3HT). Esto explica el transporte activado en fases poliméricas ordenadas, detallando los estados atrapados por primera vez.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Química computacional es la química computacional.
- La ciencia de los polímeros es la ciencia de los polímeros.
Sus antecedentes:
- El poli ((3-hexiltiofeno) (P3HT) es un polímero semiconductor ampliamente utilizado.
- Comprender el comportamiento del portador de carga es crucial para la electrónica de polímeros.
- Los modelos existentes a menudo carecen de detalles microscópicos.
Objetivo del estudio:
- Para aclarar la estructura electrónica de los portadores de carga en P3HT.
- Explicar los mecanismos detrás del transporte activado en fases poliméricas ordenadas.
- Para proporcionar una descripción químicamente detallada de los estados atrapados.
Principales métodos:
- Combinación de métodos computacionales químicos clásicos y cuánticos.
- Análisis de la localización de la portadora de carga.
- Investigación de los estados atrapados en la P3HT cristalina.
Principales resultados:
- Los portadores de carga en P3HT están localizados debido a las trampas de larga vida.
- Estas trampas existen incluso en la fase cristalina.
- El transporte activado en P3HT ordenado se explica independientemente de la energía polaron.
- Los estados atrapados se describen con un detalle químico sin precedentes.
Conclusiones:
- La química computacional cierra la brecha entre las descripciones fenomenológicas y microscópicas del transporte de carga en polímeros.
- El estudio proporciona una comprensión detallada de la localización del portador de carga y los mecanismos de transporte en P3HT.
- Este trabajo ofrece una base para el diseño de polímeros semiconductores mejorados.
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