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Pirólisis confinada dentro de marcos metálico-orgánicos para formar grupos uniformes de Ru para la oxidación
Shufang Ji1, Yuanjun Chen1, Qiang Fu2
1Department of Chemistry, Tsinghua University , Beijing 100084, China.
Journal of the American Chemical Society
|July 12, 2017
Resumen
Los investigadores desarrollaron un nuevo método para crear grupos uniformes de rutenio (Ru3 / CN) utilizando marcos de imidazolato zeolítico. Estos nuevos grupos muestran una actividad catalítica significativamente mejorada para la oxidación del alcohol.
Área de la Ciencia:
- Ciencias de los materiales
- Catálisis
- Nanotecnología
Sus antecedentes:
- Los catalizadores dispersos atómicamente ofrecen una reactividad única.
- El control del tamaño y la estabilidad del racimo es crucial para el rendimiento catalítico.
- Los marcos de imidazolato zeolítico (ZIF) pueden actuar como entornos de reacción a nanoescala.
Objetivo del estudio:
- Desarrollar una nueva estrategia para sintetizar grupos uniformes dispersos atómicamente.
- Para utilizar precursores separados por la jaula para la formación controlada de racimos.
- Para investigar el rendimiento catalítico de los grupos de rutenio sintetizados.
Principales métodos:
- Se empleó una estrategia de preselección y pirólisis de precursores separados por jaula.
- El carbonilo de rutenio (Ru3(CO) 12 bien definido estaba confinado dentro de los marcos de imidazolato zeolítico (ZIF).
- El tratamiento térmico bajo confinamiento produjo racimos de rutenio estabilizados con nitrógeno (Ru3/CN).
Principales resultados:
- Se sintetizaron con éxito racimos uniformes de Ru3 estabilizados por especies de nitrógeno.
- El catalizador Ru3/CN demostró una excelente actividad catalítica (100% de conversión) y quimioselectividad (100% para el 2-aminobenzaldehído).
- Ru3/CN exhibió una frecuencia de rotación significativamente mayor (TOF) de 4320 h-1 en comparación con las partículas pequeñas de Ru (184 h-1).
Conclusiones:
- La estrategia de pirólisis confinada en jaula es efectiva para producir racimos de metal uniformes y dispersos atómicamente.
- El rendimiento catalítico mejorado de Ru3/CN se atribuye a las interacciones únicas Ru-reactivo.
- Este enfoque ofrece una ruta prometedora para el diseño de catalizadores avanzados con una actividad superior.
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