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Parejas de ácido-base activas de Lewis inducidas por foto en un marco metálico-orgánico para la activación de H2
Bryan Kit Yue Ng1, Zi-Jian Zhou2, Ting-Ting Liu2
1Department of Chemistry, University of Oxford, Oxford OX1 3QR, U.K.
Journal of the American Chemical Society
|August 23, 2023
Resumen
La luz activa catalizadores de rutenio en estructuras orgánicas metálicas para la activación del hidrógeno. Este sistema de par de Lewis frustrado (FLP), formado a través de la transferencia de carga fotoinducida, permite el intercambio H2-D2, superando la inactividad térmica.
Área de la Ciencia:
- Catálisis
- Ciencias de los materiales
- La fotoquímica
Sus antecedentes:
- Los pares de Lewis frustrados (FLPs) son sitios altamente reactivos para la activación de moléculas pequeñas.
- Las estructuras metal-orgánicas (MOF) ofrecen plataformas sintonizables para la catálisis heterogénea.
Objetivo del estudio:
- Investigar la actividad catalítica de los MOF de Ru injertados con enlaces que contienen N para la activación de H2O.
- Explorar el mecanismo de activación del H2 bajo irradiación luminosa.
Principales métodos:
- Injerto de complejos de rutenio en enlaces que contienen N en MOF.
- Reacciones de intercambio isotópico.
- Cálculos de la teoría funcional de la densidad dependiente del tiempo (TDDFT).
- Espectroscopia infrarroja con transformación de Fourier (FTIR) y resonancia magnética nuclear 2D (RMN).
Principales resultados:
- Los Ru MOF injertados no muestran activación térmica H2.
- La iluminación induce la polarización de carga (Ru+-N) a través de la transferencia de carga de metal a ligando.
- Las especies de tipo FLP fotoinducidas catalizan efectivamente el intercambio H2D2.
- FTIR y RMN 2D confirman la formación de productos intermedios reactivos.
Conclusiones:
- El comportamiento del par de Lewis frustrado inducido por la foto en Ru MOFs permite una activación eficiente de H2.
- La luz es crucial para generar sitios catalíticos activos en estos sistemas.
- Este trabajo presenta un nuevo enfoque fotocatalítico para la activación de H2 utilizando catalizadores basados en MOF.
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