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Developing Photosensitizer-Cobaloxime Hybrids for Solar-Driven H2 Production in Aqueous Aerobic Conditions
Published on: October 5, 2019
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Diseño racional de híbridos de marco orgánico covalente para la evolución mejorada del hidrógeno fotocatalítico
Kerstin Gottschling1,2,3,4, Gökcen Savasci1,2,3,4, Hugo Vignolo-González1
1Max Planck Institute for Solid State Research, Heisenbergstrasse 1, 70569 Stuttgart, Germany.
Journal of the American Chemical Society
|June 23, 2020
Resumen
Las estructuras orgánicas covalentes (COF) funcionalizadas con cocatalizadores de cobaloxima demuestran una mayor estabilidad y una actividad prolongada para la evolución del hidrógeno. Este avance ofrece una alternativa prometedora a los catalizadores basados en platino para las tecnologías de combustible solar.
Área de la Ciencia:
- Ciencias de los materiales
- Catálisis
- Energía renovable
Sus antecedentes:
- Los marcos orgánicos covalentes (COF) ofrecen andamios sintonizables para las reacciones químicas, incluida la imitación de la fotosíntesis natural.
- Se necesitan alternativas eficientes, estables y económicas a los cocatalizadores basados en platino para la evolución del hidrógeno impulsado por la luz.
- Los complejos de cobaloxima se exploran como potenciales cocatalizadores de la evolución del hidrógeno.
Objetivo del estudio:
- Desarrollar e investigar nuevos catalizadores de cobalxima respaldados por COF para mejorar la evolución del hidrógeno fotocatalítico.
- Comprender el mecanismo detrás de la actividad mejorada y la estabilidad de los cocatalizadores inmovilizados.
Principales métodos:
- Síntesis de cobalosimas cloropiridina funcionalizadas inmovilizadas en una columna vertebral de COF-42 a base de hidrazona.
- Los experimentos de evolución del hidrógeno fotocatalítico.
- Cálculos avanzados de RMN en estado sólido y cuántico-químicos para dilucidar la estructura del sitio activo y la fotorreactividad.
Principales resultados:
- Los materiales de COF-42 atados a la cobalxima mostraron una actividad fotocatalítica mejorada y prolongada en comparación con los sistemas fisicorbados.
- Una verdadera interacción entre la columna vertebral de COF y la cobaloxima facilitó la coordinación del catalizador, aumentando la reactividad y obstaculizando la degradación.
- Los catalizadores inmovilizados demostraron una excelente estabilidad y una reactividad prolongada.
Conclusiones:
- Los materiales de COF atados a la cobalxime son catalizadores eficaces y estables de la evolución del hidrógeno.
- Los hallazgos ponen de relieve el potencial de los materiales basados en COF para futuras tecnologías de combustible solar.
- El estudio proporciona información sobre el mecanismo de mejora de la actividad catalítica a través de interacciones específicas COF-cocatalizador.
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