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Functionalization of Single-walled Carbon Nanotubes with Thermo-reversible Block Copolymers and Characterization by Small-angle Neutron Scattering

Functionalization of Single-walled Carbon Nanotubes with Thermo-reversible Block Copolymers and Characterization by Small-angle Neutron Scattering

Published on: June 1, 2016

Reactividad dependiente de la estructura de los nanotubos de carbono semiconductores de pared única con sales de

Condell D Doyle¹, John-David R Rocha, R Bruce Weisman

¹Departments of Chemistry and Mechanical Engineering and Materials Science, the R.E. Smalley Institute for Nanoscale Science and Technology, MS-222, Rice University, 6100 Main Street, Houston, Texas 77005, USA.

Journal of the American Chemical Society

|May 6, 2008

Resumen

Las reacciones de las sales de diazonio apagan la fluorescencia de los nanotubos de carbono de una sola pared semiconductores (SWCNT). La reactividad depende de las brechas de banda de SWCNT y los sustitutos de sal, lo que afecta a la separación de SWCNT metálica y semiconductora.

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 (SWCNT) poseen propiedades electrónicas únicas.
La fluorescencia de los SWCNT semiconductores es sensible a las modificaciones químicas.
La funcionalización selectiva es crucial para separar los tipos de SWCNT.

Objetivo del estudio:

Para investigar la reacción de las sales de diazonio con los SWCNTs.
Para comprender la reactividad dependiente de la estructura en la funcionalización de la pared lateral SWCNT.
Evaluar el impacto de estas reacciones en las estrategias de separación de SWCNT.

Principales métodos:

Se utilizó espectroscopia de fluorescencia con resolución espectral.
Estudió las reacciones de varias sales de benzenediazonium 4-sustituidas con SWCNTs.
Se analizó la reactividad de SWCNT en diferentes condiciones de pH (pH 10 y pH 5,5).

Principales resultados:

La adición de sal de diazonium apaga la fluorescencia del infrarrojo cercano SWCNT a través de reacciones en la pared lateral.
La reactividad de SWCNT se correlaciona con el tamaño de la brecha de banda, particularmente a pH 10.
Las tendencias de reactividad se invierten a pH 5.5 para sales específicas (R=OH).
Las reacciones ocurren tanto en los SWCNT semiconductores como en los metálicos.

Conclusiones:

La derivación de SWCNT por sales de diazonio es dependiente de la estructura.
La brecha de banda y el pH influyen en la reactividad relativa de los SWCNTs.
Las reacciones simultáneas en SWCNTs metálicos y semiconductores complican la separación selectiva.
La espectroscopia de fluorescencia es esencial para evaluar las reacciones SWCNT.

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