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Clusters de titanio (III) - óxo en un marco metálico-orgánico de apoyo de catalizadores de hidrógeno de co (II)

Pengfei Ji¹, Yang Song¹, Tasha Drake¹

¹Department of Chemistry, University of Chicago , 929 E. 57th Street, Chicago, Illinois 60637, United States.

Journal of the American Chemical Society

|December 7, 2017

Resumen

Las estructuras orgánicas metálicas (MOF) proporcionan un modelo molecular para comprender los soportes del catalizador de titanio (TiO2). El nodo Ti8 en Ti-BDC MOF permite la catálisis de hidróxido de CoII, lo que demuestra que TiIII

Área de la Ciencia:

Catálisis
Ciencias de los materiales
Química de las superficies

Sus antecedentes:

El titanio (TiO2) es un catalizador crucial en la industria química, conocido por sus fuertes interacciones con el metal.
Los mecanismos moleculares detrás de la eficacia catalítica de TiO2 son poco conocidos debido a las especies de superficie complejas.
Las estructuras metal-orgánicas (MOF) ofrecen estructuras definidas con precisión para modelar sistemas catalíticos.

Objetivo del estudio:

Desarrollar un modelo molecularmente preciso de soportes de TiO2 utilizando MOF.
Investigar el papel de los grupos de Ti-oxo en la catálisis heterogénea.
Elucidar el mecanismo de hidrogenación del areno catalizado por hidrógeno de CoII en un modelo de TiO2.

Principales métodos:

Síntesis de Ti-BDC MOF (MIL-125) que incluye un nodo Ti8 ((μ2-O) 8 ((μ2-OH) 4).
Inmovilización de catalizadores de hidróxido de carbono de un solo sitio en el nodo MOF.
Evaluación de la actividad catalítica en las reacciones de hidrogenación de arenos.
Correlación del rendimiento catalítico con el estado de reducción del grupo de Ti-oxo.

Principales resultados:

El nodo Ti8 de Ti-BDC MOF sirve como modelo de un solo sitio para soportes de TiO2.
Los catalizadores de hidruro de CoII soportados en el Ti-BDC MOF muestran una alta actividad en la hidrogenación de areno.
La actividad catalítica depende directamente de la reducción del grupo Ti-oxo a TiIII.
Esto confirma el papel crítico de TiIII en el rendimiento del catalizador.

Conclusiones:

El Ti-BDC MOF proporciona una plataforma molecularmente definida para el estudio de los catalizadores soportados por TiO2.
El estudio demuestra el papel fundamental de TiIII en las interacciones fuertes con el soporte metálico.
Este trabajo ofrece información fundamental sobre el mecanismo de los catalizadores heterogéneos soportados por TiO2.

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