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Sitio cooperativo para la mejora eficiente de la biomasa combinada con la producción de hidrógeno
Lingyou Zeng1, Yanju Chen2, Mingzi Sun3
1School of Materials Science and Engineering, Peking University, Beijing 100871, China.
Journal of the American Chemical Society
|May 30, 2023
Resumen
Este estudio introduce nuevos catalizadores Rh-O5/Ni(Fe en hidróxidos dobles en capas para la oxidación eficiente del 5-hidroximetilfurfural (HMFOR) y la catálisis de la evolución del hidrógeno (HER). Los catalizadores bifuncionales demuestran una alta actividad y estabilidad en medios alcalinos.
Área de la Ciencia:
- Ciencias de los materiales
- La electroquímica
- Catálisis
Sus antecedentes:
- Los catalizadores bifuncionales eficientes son cruciales para la coproducción de productos químicos de la biomasa y el hidrógeno.
- La adsorción competitiva de las especies de hidroxilo y HMF limita los catalizadores HMFOR y HER actuales.
Objetivo del estudio:
- Diseñar e investigar los sitios atómicos de Rh-O5/Ni (Fe) en hidróxidos dobles con capas nanoporosas para HMFOR y HER mejorados.
- Comprender el mecanismo catalítico y el papel de los centros de adsorción cooperativos.
Principales métodos:
- Síntesis de sitios atómicos de Rh-O5/Ni ((Fe) en hidróxidos dobles en capas tipo malla.
- Pruebas electrocatalíticas para el HMFOR y el HER en medios alcalinos.
- Espectroscopía de absorción de rayos X y infrarrojos.
- Cálculos teóricos (DFT, por sus siglas en inglés).
Principales resultados:
- Alcanza 100 mA cm-2 a una tensión baja de la célula de 1,48 V con una estabilidad de > 100 h.
- Se ha demostrado la adsorción y activación selectiva de HMF en los sitios Rh y la oxidación por OHads en los sitios Ni.
- Se reveló que los sitios de Fe mejoran la estabilidad del catalizador.
Conclusiones:
- El catalizador Rh-O5 / Ni (Fe) muestra una alta actividad y estabilidad para HMFOR y HER integrados.
- Los centros de adsorción cooperativos a escala atómica y las interacciones electrónicas son clave para una catálisis eficiente.
- Este trabajo ofrece información sobre el diseño de catalizadores para reacciones con productos intermedios competidores.
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