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Coalescencia de ciclocarbono: mecanismos para la formación de fullerenos hechos a la medida
Science (New York, N.Y.)
|March 12, 1993
Resumen
Los mecanismos de formación de los fullerenos se aclaran a través de la coalescencia de carbono ciclo[n]. Los precursores específicos del anillo de carbono, como el ciclo-C, producen selectivamente diferentes tamaños de fullereno, lo que permite una producción a medida.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Química Física es la química física.
- Nanotecnología La nanotecnología es la nanotecnología.
Sus antecedentes:
- Los fullerenos, alótropos esféricos de carbono, son ampliamente estudiados, pero sus mecanismos de formación siguen sin estar claros.
- Se dispone de cantidades macroscópicas de fullerenos, lo que impulsa la investigación sobre su síntesis y propiedades.
Objetivo del estudio:
- Para dilucidar los mecanismos que rigen la formación de fullerenos.
- Para investigar el papel de los ciclo[n] carbonos en la síntesis selectiva de tamaño de los fullerenos.
- Explorar el potencial para el control de la distribución de tamaño fullereno.
Principales métodos:
- Análisis de la evidencia espectral de masas. análisis de pruebas espectral de masas.
- Estudio de la formación de fullereno a través de la coalescencia de ciclo[n] carbono (por ejemplo, ciclo-C[30], ciclo-C[18], ciclo-C[24])).
Principales resultados:
- Se obtuvo evidencia de crecimiento de fullereno selectivo por tamaño a través de la coalescencia de carbono ciclo[n].
- La coalescencia del ciclo-C 30 produce predominantemente buckminsterfullereno (C 60).
- Los anillos más pequeños, el ciclo-C18 y el ciclo-C24, producen preferentemente el fullereno C70 a través de distintos intermediarios.
Conclusiones:
- El estudio proporciona nuevos conocimientos sobre las vías de formación de fullerenos.
- La adaptación de las distribuciones de tamaño de los fullerenos puede lograrse modificando las propiedades de los precursores.
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