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Updated: Sep 29, 2025
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A Simple, Low-cost, and Robust System to Measure the Volume of Hydrogen Evolved by Chemical Reactions with Aqueous Solutions
Published on: August 17, 2016
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Procesos de Volmer/Tafel con derrame de hidrógeno que permiten la reacción de evolución de hidrógeno alcalino de
Huai Qin Fu1, Min Zhou2, Peng Fei Liu3
1Centre for Catalysis and Clean Energy, Gold Coast Campus, Griffith University, Gold Coast, QLD 4222, Australia.
Journal of the American Chemical Society
|March 18, 2022
Resumen
Este estudio introduce un nuevo electrocatalizador Ni3S2/Cr2S3 para una reacción eficiente de evolución del hidrógeno (HER) en la electrólisis del agua alcalina. El catalizador logra altas densidades de corriente optimizando la disociación del agua y la formación de hidrógeno a través del derrame de hidrógeno.
Área de la Ciencia:
- La electroquímica
- Ciencias de los materiales
- Catálisis
Sus antecedentes:
- La producción industrial de hidrógeno a través de la electrólisis del agua alcalina requiere electrocatalizadores eficientes para la reacción de evolución del hidrógeno (HER).
- Los electrocatalizadores HER existentes luchan por mantener el rendimiento a altas densidades de corriente debido a problemas como la alta cobertura de hidrógeno y los bajos potenciales excesivos.
- El desarrollo de catalizadores que funcionen eficazmente a densidades de corriente a nivel de amperios es crucial para las aplicaciones prácticas.
Objetivo del estudio:
- Desarrollar un nuevo electrocatalizador para la electrólisis del agua alcalina capaz de operar a densidades de corriente relevantes para la industria, a nivel de amperios.
- Aclarar las vías mecanicistas que permiten un alto rendimiento, abordando específicamente la disociación del agua y la formación de hidrógeno.
- Para superar las limitaciones de la alta cobertura de hidrógeno en los sitios de disociación de agua bajo altas densidades de corriente.
Principales métodos:
- Hibridación sinérgica de Ni3S2 y Cr2S3 para crear sitios activos duales.
- Estudios experimentales y teóricos para investigar los mecanismos de reacción, incluida la adsorción de agua, la disociación y el derrame de hidrógeno.
- Mediciones electroquímicas para evaluar el rendimiento del catalizador, centrándose en la densidad de corriente y el exceso de potencial en medios alcalinos.
Principales resultados:
- El electrocatalizador híbrido Ni3S2/Cr2S3 facilita la disociación del agua y la formación de hidrógeno.
- El catalizador mitiga efectivamente la inhibición de la alta cobertura de hidrógeno y promueve las vías de reacción Volmer/Tafel.
- Se logra una alta densidad de corriente de 3,5 A cm -2 a un bajo sobrepotencial de 251 ± 3 mV en 1,0 M KOH.
Conclusiones:
- El electrocatalizador Ni3S2/Cr2S3 demuestra un rendimiento excepcional para la reacción de evolución del hidrógeno a altas densidades de corriente.
- El efecto sinérgico y el mecanismo de derrame de hidrógeno son clave para superar las limitaciones de rendimiento en la electrólisis del agua alcalina.
- Este trabajo ofrece una estrategia prometedora para el diseño de electrocatalizadores avanzados para la producción de hidrógeno a gran escala.
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