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Preparation and Characterization of C60/Graphene Hybrid Nanostructures
Published on: May 15, 2018
Nuevas fases de c60 sintetizadas a alta presión
Science (New York, N.Y.)
|June 10, 1994
Resumen
La alta presión y temperatura transforman el fullereno C ((60) en dos estructuras metastables. Estas fases vuelven a la forma original de C60) cuando se calientan, lo que indica el potencial de nuevos materiales de carbono.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Química Química es la química.
- Física del estado sólido Física del estado sólido
Sus antecedentes:
- El fullereno C ((60) es un alotrópico único de carbono con una estructura esférica.
- Comprender el comportamiento de alta presión y alta temperatura del C60) es crucial para el desarrollo de nuevos materiales de carbono.
Objetivo del estudio:
- Para investigar las transformaciones estructurales del fullereno (C60) bajo alta presión y temperatura.
- Para caracterizar las fases metestables resultantes y sus propiedades.
Principales métodos:
- Síntesis de las fases de C60) a 5 gigapascales y temperaturas que oscilan entre 300°C y 800°C.
- Caracterización estructural utilizando difracción de rayos X (implicado por parámetros de celosía).
- Análisis espectroscópico que incluye infrarrojo (IR), Raman y resonancia magnética nuclear (RMN).
Principales resultados:
- Se formaron dos estructuras metastables distintas: una fase cúbica centrada en la cara (300-400 ° C) y una fase romboédrica (500-800 ° C).
- La fase romboédrica exhibe parámetros de red hexagonal a(o) = 9.22 Å y c(o) = 24.6 Å.
- Los datos espectroscópicos indican una reducción significativa en la simetría icosaédrica, lo que sugiere un enlace intermolecular.
Conclusiones:
- El fullereno C ((60) puede convertirse en fases metastables inducidas por la presión y la temperatura.
- Estas fases se caracterizan por una simetría reducida y un enlace químico potencial entre las moléculas de C60.
- Las fases sintetizadas vuelven a su estado original de 60 °C al calentarse a 300 °C a presión ambiente.
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