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Catálisis monoatómica asistida por la superestructura en carburos de tungsteno para reacciones bifuncionales con

Hongguan Li^1,2,3, Wu Wang⁴, Sikang Xue⁵

¹School of Metallurgy, Northeastern University, Shenyang 110819, Liaoning, People's Republic of China.

Journal of the American Chemical Society

|March 22, 2024

Resumen

Desarrollamos un nuevo catalizador de un solo átomo asistido por superestructura en carburos de tungsteno para baterías de zinc-aire mejoradas. Este catalizador aumenta significativamente la cinética de la reacción de oxígeno, logrando una brecha de potencial baja y una alta densidad de potencia.

Área de la Ciencia:

Ciencias de los materiales
La electroquímica
Nanotecnología

Sus antecedentes:

La catálisis de un solo átomo (SAC) es crucial para los electrocatalizadores de alto rendimiento en las baterías de zinc-aire.
El diseño de SAC con suficiente fuerza motriz para las reacciones de oxígeno multielectrónico sigue siendo un desafío importante.

Objetivo del estudio:

Desarrollar un nuevo catalizador monoatómico asistido por superestructura (SAC) en carburos de tungsteno para reacciones bifuncionales de oxígeno.
Investigar el papel de las superestructuras ordenadas en la mejora de la actividad catalítica.

Principales métodos:

Fabricación de un SAC asistido por la superestructura en carburos de tungsteno.
Caracterización experimental de la estructura y las propiedades del catalizador.
Cálculos teóricos (por ejemplo, DFT) para comprender los mecanismos de reacción y la energía.

Principales resultados:

Descubrimiento de superestructuras de cobalto altamente ordenadas en la interfaz de carburo de tungsteno, induciendo deformación.
Efectos sinérgicos demostrados entre las superestructuras y los sitios atómicos individuales, reduciendo la energía de adsorción intermedia y el sobrepotencial.
Se logró una brecha de potencial ultrabaja de 0.623 V para las reacciones de oxígeno bifuncional.
Las baterías de zinc-aire ensambladas ofrecían una alta densidad de potencia de 188,5 mW cm-2.

Conclusiones:

El catalizador desarrollado exhibe una actividad bifuncional superior para las reacciones de evolución y reducción del oxígeno.
La combinación de sitios atómicos individuales y superestructuras ordenadas ofrece una nueva estrategia para el diseño avanzado de catalizadores.
Este trabajo allana el camino para la próxima generación de catálisis atómica en dispositivos de almacenamiento de energía.

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