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Updated: Sep 9, 2025
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Published on: December 6, 2021
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Una red interfacial robusta de enlaces de hidrógeno en sitios duales de Ru-N-Ni con carga positiva impulsa la
Longyu Qiu1, Fenyang Tian1, Lin He1
1State Key Laboratory of Urban Water Resource and Environment, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, 150001, China.
Advanced materials (Deerfield Beach, Fla.)
|September 2, 2025
Resumen
Este estudio presenta catalizadores de doble sitio con puente de nitrógeno para la electrocatálisis de hidrógeno mejorada. Estos catalizadores mejoran la transferencia de masa y la estabilidad en las reacciones de oxidación y evolución del hidrógeno (HOR y HER).
Área de la Ciencia:
- Ciencias de los materiales
- La electroquímica
- Catálisis
Sus antecedentes:
- Los catalizadores de doble ubicación basados en rutenio (Ru) son prometedores para la electrocatálisis de hidrógeno alcalino.
- Los desafíos incluyen la transferencia de masa insuficiente y la dificultad para manipular la estructura del agua interfacial.
- La optimización de la adsorción de los intermedios de reacción es crucial para la eficiencia del catalizador.
Objetivo del estudio:
- Desarrollar un nuevo diseño de catalizador para reacciones mejoradas de oxidación y evolución de hidrógeno alcalino (HOR y HER).
- Investigar el papel de la estructura de agua interfacial y las redes de enlace de hidrógeno en el rendimiento del catalizador.
- Para mejorar la transferencia de masa y la estabilidad en las reacciones de hidrógeno electrocatalíticas.
Principales métodos:
- Síntesis de catalizadores de doble ubicación de Ru y Ni cargados positivamente con puente de nitrógeno (Ru-Ni3N).
- Investigación de la orientación interfacial del agua y de la formación de redes de enlaces de hidrógeno.
- Pruebas electrocatalíticas para HOR y HER, incluidas las mediciones de actividad de masa y estabilidad.
- Análisis de los canales de transferencia de carga y las propiedades electrónicas de los sitios Ru y Ni.
Principales resultados:
- Los catalizadores Ru-Ni3N exhiben una orientación de agua ordenada con una configuración "O-down" favorable.
- Una red de enlaces de hidrógeno interfacial mejorada promueve la transferencia de masa.
- La transferencia eficiente de carga a través de puentes Ru-N-Ni estabiliza los intermedios y mejora el envenenamiento por anti-CO.
- Se logró una actividad de masa de 60,6 A g-1 para HOR, entre las más altas para los catalizadores basados en Ru.
- Se ha demostrado la baja tensión de la célula (1,79 V a 1 A cm-2) para los electrolizadores de agua con membrana de intercambio aniónico y la estabilidad a largo plazo (> 550 h a 500 mA cm-2).
Conclusiones:
- La estrategia desarrollada de catalizador de doble ubicación con puente de nitrógeno mejora efectivamente la electrocatálisis de hidrógeno alcalino.
- La modulación de la red de enlaces de hidrógeno interfacial es un enfoque viable para mejorar la transferencia de masa y la actividad catalítica.
- Esta estrategia tiene un potencial significativo para aplicaciones en pilas de combustible de hidrógeno y en la electrólisis del agua.
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