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Transporte de carga en oligómeros conjugados definidos por secuencia
Hao Yu1, Songsong Li2,3, Kenneth E Schwieter4
1Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States.
Journal of the American Chemical Society
|February 19, 2020
Resumen
La secuencia de monómeros en polímeros sintéticos tiene un impacto significativo en el transporte de cargas. Secuencias específicas en oligómeros conjugados mejoran la conductividad molecular más de 10 veces al crear vías de carga únicas.
Área de la Ciencia:
- Química de los polímeros
- Ciencias de los materiales
- La electrónica molecular
Sus antecedentes:
- Comprender la relación entre la secuencia de monómeros y las propiedades del material es crucial para los polímeros sintéticos.
- El transporte de carga en oligómeros conjugados es un factor clave en la electrónica molecular.
Objetivo del estudio:
- Investigar cómo la secuencia monomérica primaria afecta el transporte de carga en las uniones de una sola molécula.
- Sintetizar y caracterizar los oligómeros conjugados definidos por secuencia.
Principales métodos:
- Síntesis iterativa utilizando la reacción de van Leusen para crear oligómeros definidos por secuencia (2-7 unidades).
- Caracterización de las propiedades de transporte de carga mediante la técnica de unión de ruptura de microscopio de túnel de barrido (STM-BJ).
- Medición de la conductividad molecular para varias longitudes de oligómero.
Principales resultados:
- Se encontró que las secuencias específicas de monómeros mejoran la conductividad molecular en más de 10 veces.
- Los pentámeros definidos por secuencia con grupos de imidazol o pirrol facilitaron las vías de conducción múltiple.
- El obstáculo estérico y la direccionalidad del heterociclo juegan un papel crítico en el transporte de carga.
Conclusiones:
- La secuencia de monómeros es un parámetro de diseño crítico para controlar el transporte de carga en oligómeros conjugados.
- La adaptación de la estructura molecular puede conducir a un mayor rendimiento en los dispositivos electrónicos moleculares.
- Este estudio proporciona información para el diseño de componentes electrónicos moleculares avanzados.
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