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Construcción de un catalizador de impresión molecular altamente activo y selectivo para la hidrogenación

Dongcheng He^1,2, Teng Li¹, Xingchao Dai¹

¹State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, No. 18, Tianshui Middle Road, Lanzhou 730000, China.

Journal of the American Chemical Society

|September 18, 2023

Resumen

La impresión molecular superficial mejora las reacciones catalíticas mediante la creación de cavidades precisas y nuevos sitios activos. Este nuevo enfoque mejora tanto la selectividad como la actividad del catalizador para la hidrogenación de compuestos de nitro.

Área de la Ciencia:

Catálisis
Ciencias de los materiales
Química de las superficies

Sus antecedentes:

La impresión molecular de superficie (IM) es clave para las reacciones catalíticas selectivas.
El IM tradicional sacrifica los sitios activos, reduciendo la actividad del catalizador.
Hay una necesidad de catalizadores con mayor actividad y selectividad.

Objetivo del estudio:

Desarrollar catalizadores de impresión molecular (MIC) con mejor actividad y selectividad.
Investigar la formación de nuevos sitios activos y cavidades de impresión.
Para mejorar la hidrogenación de los compuestos de nitro.

Principales métodos:

Adsorción secuencial de las moléculas de impresión (compuestos de nitro, N) y el ligando (1,10-fenantrolina, L) en Cu/Al2O3.
Preparación de las MIC de Cu/Al2O3-N-L.
Caracterización mediante investigaciones experimentales y cálculos DFT.

Principales resultados:

Los MIC desarrollados muestran una mayor selectividad catalítica y actividad para la hidrogenación de compuestos de nitro.
Formación de cavidades de impresión de precisión a partir de la presorción de N.
Creación de nuevos sitios activos de Cu-N en la interfaz cobre/L.

Conclusiones:

El efecto de impresión molecular se atribuye a nuevos sitios activos de Cu-N y cavidades de impresión.
Estas características promueven tanto la selectividad como la actividad catalítica.
El estudio presenta una estrategia para diseñar MICs altamente eficientes.

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