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Disminución de las transiciones de brecha de banda de los nanotubos de carbono de pared única en complejación con
K A Shiral Fernando1, Yi Lin, Wei Wang
1Department of Chemistry, Howard L. Hunter Chemistry Laboratory, Clemson University, Clemson, SC 29634-0973, USA.
Journal of the American Chemical Society
|August 19, 2004
Resumen
La complejación no covalente de nanotubos de carbono con moléculas aromáticas activa y desactiva de manera reversible sus bandas de absorción de casi IR. Este hallazgo ofrece nuevas posibilidades para controlar las propiedades ópticas de los nanotubos.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Nanotecnología La nanotecnología es la nanotecnología.
- Química Física es la química física.
Sus antecedentes:
- Los nanotubos de carbono de pared única semiconductores exhiben bandas de absorción características en el infrarrojo cercano (IR cercano).
- Estas bandas corresponden a las transiciones electrónicas en las singularidades de van Hove (S11 y S22) en su densidad de estados.
Objetivo del estudio:
- Investigar el efecto de la complejación no covalente en el espectro de absorción de luz casi infrarroja de los nanotubos de carbono semiconductores de pared única.
- Explorar la reversibilidad de los cambios espectrales inducidos por la complicación.
Principales métodos:
- Complejación no covalente a base de solución de nanotubos de carbono de pared única con moléculas aromáticas planas (por ejemplo, pirenos).
- Monitoreo de los espectros de absorción del infrarrojo cercano para observar cambios en las bandas S11 y S22.
Principales resultados:
- La complejación con moléculas aromáticas lleva a la desaparición de las bandas de absorción S11 y S22.
- Los cambios espectrales observados son reversibles, lo que permite recuperar las bandas tras la eliminación de las moléculas aromáticas.
Conclusiones:
- La complejación no covalente proporciona un método reversible para modular las propiedades ópticas casi IR de los nanotubos de carbono semiconductores.
- Este control de las propiedades ópticas abre caminos para aplicaciones en dispositivos ópticos sintonizables y sensores.
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