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Crecimiento selectivo de matrices de nanotubos de carbono de pared única de diámetro subnanométrico en CVD sin
Lixing Kang1,2,3, Shibin Deng1, Shuchen Zhang1
1Center for Nanochemistry, Beijing Science and Engineering Center for Nanocarbons, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University , Beijing 100871, P. R. China.
Journal of the American Chemical Society
|September 23, 2016
Resumen
Los investigadores desarrollaron un método para el cultivo de matrices de nanotubos de carbono de pared única de pequeño diámetro (SWNT) con quiralidad controlada utilizando catalizadores de carburo de molibdeno sólido. Este avance es crucial para los dispositivos optoelectrónicos de alto rendimiento en el infrarrojo cercano.
Área de la Ciencia:
- Ciencias de los materiales
- Nanotecnología
- Física de la materia condensada
Sus antecedentes:
- Los nanotubos de carbono de pared única (SWNT) son cruciales para los dispositivos optoelectrónicos avanzados.
- El control del diámetro y la quiralidad de SWNT es clave para optimizar sus propiedades ópticas y electrónicas.
- Los SWNT de diámetro subnanométrico con espacios de banda más grandes son particularmente deseables para aplicaciones cercanas al infrarrojo.
Objetivo del estudio:
- Desarrollar un método de crecimiento selectivo para matrices SWNT de diámetro subnanométrico bien alineadas.
- Para lograr una distribución estrecha de la quiralidad en los SWNT cultivados.
- Para mejorar la densidad de SWNT para la fabricación de dispositivos prácticos.
Principales métodos:
- Utilizando catalizadores de carburo de molibdeno sólido (Mo2C) para el crecimiento de SWNT.
- Utilizando alimentación baja en carbono y tiempos de crecimiento cortos en un entorno libre de hidrógeno de deposición de vapor químico (CVD).
- Investigar el papel del tamaño del catalizador y los procesos de recocido en las características del SWNT.
- Caracterización del diámetro, la densidad y la distribución de la quiralidad de SWNT.
Principales resultados:
- Se crearon con éxito matrices SWNT alineadas con diámetros subnanométricos (∼84% entre 0,75 y 0,95 nm).
- Se obtiene una distribución de quiralidad estrecha, con quiralidades específicas dominantes (> 73%).
- Control demostrado del crecimiento de SWNT mediante la manipulación del tamaño del catalizador y la velocidad de alimentación de carbono.
- Aumento de la densidad de SWNT a ∼15 tubos/μm en sustratos de zafiro mediante recocido.
Conclusiones:
- Los catalizadores sólidos de Mo2C permiten el crecimiento selectivo y a corto plazo de SWNT de subnanómetros con quiralidad controlada.
- El método ofrece una vía para adaptar las propiedades de SWNT a aplicaciones específicas.
- Esta investigación proporciona información valiosa para el control estructural de los SWNT alineados en la nanoelectrónica.
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