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Espectro óptico asignado por la estructura de los nanotubos de carbono de pared única
Sergei M Bachilo1, Michael S Strano, Carter Kittrell
1Department of Chemistry, Center for Nanoscale Science and Technology, and Center for Biological and Environmental Nanotechnology, Rice University, 6100 Main Street, Houston, TX 77005, USA.
Science (New York, N.Y.)
|December 3, 2002
Resumen
La espectrofluorimetría y la espectroscopia de Raman revelan distintas transiciones ópticas para más de 30 especies semiconductoras de nanotubos de carbono de pared única (SWNT). Esto permite una rápida caracterización de muestras de SWNT, mapeando las transiciones a estructuras específicas de nanotubos.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Nanotecnología La nanotecnología es la nanotecnología.
- La espectroscopia es una técnica de espectroscopia.
Sus antecedentes:
- Los nanotubos de carbono de pared única (SWNT) poseen propiedades electrónicas únicas.
- Caracterizar la diversidad de SWNT en muestras masivas es un desafío.
- La espectroscopia óptica ofrece el potencial para el análisis detallado de SWNT.
Objetivo del estudio:
- Identificar y mapear distintas transiciones electrónicas para numerosas especies de SWNT semiconductores.
- Para correlacionar las transiciones ópticas con estructuras específicas (n,m) de nanotubos.
- Evaluar la utilidad de la espectroscopia óptica para la caracterización de muestras masivas de SWNT.
Principales métodos:
- Mediciones espectrofluorimétricas de SWNT en suspensiones acuosas de surfactantes.
- Espectroscopia de resonancia Raman. espectroscopia de resonancia Raman. espectroscopia de resonancia Raman. espectroscopia de resonancia Raman.
- Combinación de datos ópticos y Raman para el mapeo estructural.
Principales resultados:
- Identificación de distintas transiciones de absorción y emisión para más de 30 especies de SWNT semiconductores.
- Mapeo exitoso de las transiciones ópticas a estructuras específicas de nanotubos (n,m).
- Demostración de la espectroscopia óptica para la determinación rápida del diámetro SWNT y las distribuciones de ángulo quiral.
Conclusiones:
- La espectroscopia óptica, combinada con los datos de Raman, proporciona una poderosa herramienta para el análisis detallado de la composición de SWNT.
- Las frecuencias de transición medidas se desvían de los modelos teóricos simples, lo que sugiere deformación trigonal y efectos excitónicos.
- Este enfoque permite una caracterización rápida y no destructiva de mezclas complejas de SWNT.
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