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Efecto cooperativo de los cationes y la estructura del catalizador en el ajuste de la evolución del hidrógeno

Akansha Goyal¹, Sheena Louisia¹, Pricilla Moerland¹

¹Leiden Institute of Chemistry, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands.

Journal of the American Chemical Society

|March 7, 2024

Resumen

Los cationes que interactúan con los sitios de paso de platino controlan la actividad de la reacción de evolución del hidrógeno (HER) en medios alcalinos. La optimización de HER requiere adaptar tanto la composición del catalizador como la del electrolito para mejorar la electrólisis del agua.

Área de la Ciencia:

La electroquímica
Ciencias de los materiales
Catálisis

Sus antecedentes:

La reacción de evolución del hidrógeno (HER) es crucial para los electrolizadores de agua alcalina.
Los descriptores de actividad tradicionales no capturan con precisión la cinética de HER en medios alcalinos.
El mecanismo preciso y la fuerza motriz de HER siguen siendo objeto de debate.

Objetivo del estudio:

Para investigar la tasa de HER dependiente del pH y el catión en electrodos de cristal único de platino.
Para aclarar el papel de los cationes y los sitios de paso en la cinética de HER.
Identificar estrategias para optimizar la actividad de HER.

Principales métodos:

Mediciones cinéticas extensas en electrodos de un solo cristal de platino.
Análisis de las tasas de HER bajo diferentes concentraciones de pH y cationes.
Investigación de las interacciones de los cationes con los sitios y las terrazas de los escalones de platino.

Principales resultados:

Los cationes que interactúan con los sitios del paso de platino controlan significativamente la actividad de HER.
Los efectos catiónicos son mínimos en las terrazas de platino (Pt 111, Pt 100).
Las tendencias de actividad divergentes observadas en las superficies escalonadas frente a las terrazas resaltan la influencia de los cationes.

Conclusiones:

La actividad de HER está modulada por las interacciones paso- catión.
La optimización de HER implica ajustar estas interacciones a través de la deposición selectiva de átomos y la composición de electrolitos.
La adaptación sinérgica del catalizador y el electrolito es esencial para maximizar la actividad de HER.

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