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La transmutación de los fullerenos
R James Cross1, Martin Saunders
1Department of Chemistry, Yale University, PO Box 208107, New Haven, Connecticut 06520-8107, USA. james.cross@yale.edu
Journal of the American Chemical Society
|March 3, 2005
Resumen
La pirólisis de fullerenos más grandes como C76, C78 y C84 causó pérdida de carbono y formación de fullerenos más pequeños. El helio encapsulado en C76 se perdió en su mayoría, mientras que C60 se mantuvo intacto durante la descomposición a alta temperatura.
Área de la Ciencia:
- La química de los fullerenos es muy compleja.
- Ciencias de los materiales de alta temperatura Ciencias de los materiales de alta temperatura.
Sus antecedentes:
- Los fullerenos son alótropos del carbono con estructuras únicas parecidas a una jaula.
- Comprender la estabilidad del fullereno bajo estrés térmico es crucial para sus aplicaciones.
Objetivo del estudio:
- Para investigar las vías de descomposición térmica de varios fullerenos.
- Para determinar el efecto de la pirólisis en la estructura del fullereno y las especies encapsuladas.
Principales métodos:
- Sublimación de los fullerenos en gas argón.
- Pirólisis en un horno a aproximadamente 1000°C.
- Análisis de los productos de descomposición y retención de helio encapsulado.
Principales resultados:
- C76, C78 y C84 fácilmente perdieron átomos de carbono, formando fullerenos más pequeños.
- Se observó isomerización para C78 durante la pirólisis.
- La pirólisis de (3) He@C76 resultó en una pérdida significativa de helio encapsulado.
- C60 demostró una alta estabilidad térmica, sin descomposición ni pérdida de helio.
Conclusiones:
- Los fullerenos más grandes sufren fácil extrusión de carbono y fragmentación a altas temperaturas.
- La estabilidad de las especies encapsuladas varía significativamente con el tamaño de la jaula de fullereno.
- El C60 exhibe una notable resistencia térmica, lo que lo hace adecuado para entornos de alta temperatura.
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