Las propiedades ópticas y de transporte de carga de los materiales discoticos con grandes núcleos de hidrocarburos aromáticos
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Excitonic Hamiltonians for Calculating Optical Absorption Spectra and Optoelectronic Properties of Molecular Aggregates and Solids
Published on: May 27, 2020
Michael G Debije1, Jorge Piris, Matthijs P de Haas
1Radiation Chemistry Department, IRI, Delft University of Technology, Mekelweg 15, 2629 JB Delft, The Netherlands.
Journal of the American Chemical Society
|April 9, 2004
Resumen
Este estudio investigó el transporte de carga en moléculas discoticas con diferentes tamaños de núcleos aromáticos policíclicos. Se observó una alta movilidad de carga unidimensional, pero no aumentó con el tamaño del núcleo como se hipotetizó anteriormente.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Electrónica orgánica y electrónica orgánica.
- Química Física es la química física.
Sus antecedentes:
- Las moléculas discóticas son prometedoras para la electrónica orgánica debido a su autoensamblaje en columnas unidimensionales.
- Comprender el transporte de carga en estos materiales es crucial para el rendimiento del dispositivo.
Objetivo del estudio:
- Investigar las propiedades de absorción óptica y transporte de carga de moléculas discoticas con diferentes tamaños de núcleos aromáticos policíclicos.
- Para determinar el efecto del tamaño del núcleo en la movilidad unidimensional de la carga intracolumnar.
Principales métodos:
- Síntesis de moléculas discóticas con núcleos aromáticos policíclicos de tamaños n = 24, 42, 60, 78, 96 y 132 átomos de carbono.
- Espectroscopia de absorción óptica en solución diluida y películas delgadas.
- Técnica de conductividad de microondas con resolución de tiempo de pulso-radiólisis para medir la movilidad de carga intracolumnar unidimensional (Σμ1D).
Principales resultados:
- El máximo de absorción (λmax) aumentó linealmente con el tamaño del núcleo (n) como λmax = 280 + 2n.
- La movilidad unidimensional de la carga (Σμ1D) en sólidos cristalinos osciló entre 0,4 y 1,0 cm2/Vs.
- En las mesofasas discoticas, la Σμ1D osciló entre 0,080,38 cm2/Vs, más baja que en los sólidos cristalinos.
- Las movilidades observadas fueron más altas de lo que se había informado anteriormente para los derivados de trifenileno discótico.
Conclusiones:
- El estudio demuestra una alta movilidad de carga en moléculas discoticas con grandes núcleos aromáticos policíclicos.
- Contrariamente a las hipótesis anteriores, la movilidad de la carga no mostró una clara tendencia al aumento con el aumento del tamaño del núcleo en esta serie.
- Estos hallazgos proporcionan información valiosa sobre las relaciones estructura-propiedad para el diseño de semiconductores orgánicos.
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