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Las capas metálicas orgánicas basadas en cerio catalizan la reacción de evolución del hidrógeno a través de la
Yang Song1, Yunhong Pi1,2, Xuanyu Feng1
1Department of Chemistry, The University of Chicago, 929 East 57th Street, Chicago, Illinois 60637, United States.
Journal of the American Chemical Society
|April 2, 2020
Resumen
Sintetizamos la primera capa metal-orgánica (MOL) basada en cerio, Ce6-BTB, y la funcionalizamos para la evolución del hidrógeno fotocatalítico. Los MOL modificados con complejos de iridio o rutenio lograron una producción eficiente de hidrógeno bajo luz visible.
Área de la Ciencia:
- Ciencias de los materiales
- Catálisis
- La fotoquímica
Sus antecedentes:
- Los materiales a base de cerio como la cería son vitales en la catálisis.
- Las capas metálico-orgánicas (MOL) ofrecen estructuras ajustables para aplicaciones avanzadas.
Objetivo del estudio:
- Síntesis y caracterización de la primera capa metalorgánica a base de cerio (Ce6-BTB).
- Funcionalizar Ce6-BTB para la reacción fotocatalítica de evolución del hidrógeno (HER).
- Investigar el mecanismo de la fotocatálisis en los MOL funcionalizados.
Principales métodos:
- Síntesis de Ce6-BTB utilizando unidades de construcción secundarias (SBU) de Ce6 y enlaces de BTB.
- Modificación post-sintética del Ce6-BTB con fotosensibilizadores de iridio o rutenio.
- Mediciones de la reacción fotocatalítica de evolución del hidrógeno (HER) bajo luz visible.
- Estudios fotofísicos y electroquímicos para elucidar los mecanismos de reacción.
Principales resultados:
- Ce6-BTB fue sintetizado y modificado con éxito para crear Ce6-BTB-Ir y Ce6-BTB-Ru.
- Los MOL funcionalizados demostraron una HER fotocatalítica eficiente con un alto número de rotación (1357 para Ir, 484 para Ru).
- Se identificó una nueva vía de fotoexcitación dual que involucra a las SBU de Ce6 y a los fotosensibilizadores.
Conclusiones:
- Ce6-BTB-Ir y Ce6-BTB-Ru son fotocatalizadores efectivos para el HER bajo luz visible.
- La proximidad de los fotosensibilizadores y las SBU de Ce6 es crucial para una transferencia eficiente de electrones.
- El doble mecanismo de fotoexcitación mejora la actividad fotocatalítica.
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