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Oscilación del pH local inducida por la polarización Promueve la hidrogenación de CO2 catalizado por Pd
Jaeyune Ryu1, Yogesh Surendranath1
1Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States.
Journal of the American Chemical Society
|July 7, 2020
Resumen
La polarización eléctrica impulsa la catálisis no faradaica creando fluctuaciones locales de pH. Este método aumenta significativamente la hidrogenación de CO2 para formar, ofreciendo una nueva vía para una catálisis eficiente.
Área de la Ciencia:
- La electroquímica
- Catálisis
- Química Física
Sus antecedentes:
- La polarización electroquímica mejora las reacciones catalíticas no faradaicas en las interfaces sólido-líquido.
- La base mecanicista de esta promoción no se entiende bien.
- Las reacciones no faradaicas se producen sin transferencia directa de electrones desde el electrodo.
Objetivo del estudio:
- Establecer un marco mecanicista para la promoción no faradaica en medios acuosos.
- Investigar el fomento de la hidrogenación de CO2 para formar mediante polarización eléctrica.
- Comprender cómo los entornos locales influyen en la cinética de la reacción.
Principales métodos:
- Examinó la cinética de la hidrogenación de CO2 catalizada por el paladio para formar.
- Utilizó la polarización electroquímica para crear un ambiente local sin equilibrio.
- Investigó los efectos de las fluctuaciones locales del pH y las concentraciones de los reactivos.
Principales resultados:
- Se estableció un marco mecanicista basado en fluctuaciones locales de pH inducidas por reacciones faradaicas.
- La alta alcalinidad y la alta concentración de CO2, obtenidas a través de la polarización eléctrica, promueven la reacción.
- La tasa de hidrogenación de CO2 no faradaico a formato aumentó en casi tres órdenes de magnitud.
Conclusiones:
- Las fluctuaciones locales de pH inducidas por reacciones faradaicas concurrentes son clave para la promoción no faradaica.
- La polarización eléctrica puede superar las limitaciones de electrolitos a granel para crear condiciones de reacción óptimas.
- Este trabajo proporciona una base para mejorar la catálisis de hidrogenación en condiciones suaves.
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