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Funcionalización de la pared lateral covalente de los nanotubos de carbono de pared única
Rajesh K Saini1, Ivana W Chiang, Haiqing Peng
1Center for Nanoscale Science and Technology, Rice Quantum Institute, Department of Chemistry, Rice University, Houston, Texas 77005, USA.
Journal of the American Chemical Society
|March 20, 2003
Resumen
Los grupos alquilo se pueden unir a los nanotubos de fluoro utilizando reactivos de alquilitio. Los nanotubos de diámetro más pequeño se funcionalizan más fácilmente, y esta alquilación es reversible a 500°C.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Nanotecnología La nanotecnología es la nanotecnología.
- Química orgánica es la química orgánica.
Sus antecedentes:
- La funcionalización de los nanotubos de carbono es crucial para adaptar sus propiedades.
- Los reactivos de alquillitio ofrecen una vía para la modificación de la pared lateral de los nanotubos de carbono fluorados de pared única (SWNT).
Objetivo del estudio:
- Para medir cuantitativamente el grado de alquilación en SWNTs fluoro.
- Para comparar la eficiencia de alquilación de SWNTs preparados a través de diferentes métodos.
- Para investigar la estabilidad térmica y la reversibilidad del proceso de alquilación.
Principales métodos:
- La alquilación de SWNT fluoro utilizando reactivos de alquillitio.
- Análisis gravimétrico térmico (TGA) junto con espectroscopia UV-NIR para la evaluación cuantitativa de la funcionalidad.
- La termólisis en la atmósfera de argón seguida del análisis por espectrometría de masas TGA (TGA-MS).
Principales resultados:
- La medición cuantitativa del grado de alquilación de la pared lateral se logró utilizando TGA-UV-vs-NIR.
- Los SWNT producidos por el método HiPco mostraron una mayor eficiencia de alquilación en comparación con los SWNT producidos por horno láser.
- Se demostró la reversibilidad de la alquilación, con firmas espectrales de SWNT prístinas restauradas después del calentamiento a 500°C en argón.
- El análisis TGA-MS de SWNTs n-butilados identificó 1-buteno y n-butano como productos de termólisis.
Conclusiones:
- Los reactivos de alquillitio funcionalizan eficazmente las paredes laterales SWNT fluoro.
- Los SWNT de diámetro más pequeño, como los de HiPco, son más fácilmente alquilados.
- El proceso de alquilación es térmicamente reversible, lo que permite una posible regeneración de las propiedades prístinas de SWNT.
- La comprensión de los productos de dealquilación proporciona información sobre la estabilidad de la funcionalización.
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