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Síntesis general de una biblioteca de catalizadores diatómicos mediante un enfoque mediado por precursores

Yu-Xiao Zhang¹, Shengbo Zhang¹, Helai Huang¹

¹State Key Laboratory of Chemical Engineering, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China.

Journal of the American Chemical Society

|February 15, 2023

Resumen

Los investigadores desarrollaron un nuevo método para crear diversos catalizadores diatómicos (DAC) para mejorar la reactividad. Los sitios diatómicos de Fe-Cu muestran una durabilidad excepcional para las reacciones de reducción de oxígeno (ORR), ofreciendo una vía prometedora para el desarrollo de electrocatalisadores.

Área de la Ciencia:

Ciencias de los materiales
Catálisis
La electroquímica

Sus antecedentes:

Los catalizadores diatómicos (DAC) con efectos sinérgicos son cruciales para la reactividad única.
Los métodos existentes para producir diversos DAC, especialmente con diversas combinaciones de metales, son limitados.
La comprensión de la relación estructura-actividad en los DAC es clave para el diseño del catalizador.

Objetivo del estudio:

Presentar una estrategia sintética general y conveniente para la construcción de una amplia biblioteca de catalizadores diatómicos (DAC).
Explorar el potencial de estos DAC en la electrocatálisis, específicamente para la reacción de reducción de oxígeno (ORR).
Identificar DACs altamente duraderos y eficientes para aplicaciones avanzadas de electrocatalizadores.

Principales métodos:

Desarrolló un enfoque de encapsulación-pirólisis utilizando materiales porosos para albergar complejos macrocíclicos.
Estructura mediada del DAC mediante la preservación de la estructura molecular durante la pirólisis.
Sintetizó una biblioteca de centros bimetálicos homonucleares (por ejemplo, Fe2, Co2) y heteronucleares (por ejemplo, Fe-Cu, Cu-Mn).

Principales resultados:

Construido con éxito una biblioteca DAC diversa con varios centros bimetálicos homonucleares y heteronucleares.
Demostró la utilidad de la biblioteca DAC para el desarrollo de electrocatalisadores utilizando la reacción de reducción de oxígeno (ORR) como modelo.
Identificó los sitios diatómicos de Fe-Cu como excepcionalmente duraderos para la ORR, superando a otros sitios investigados.

Conclusiones:

La estrategia de encapsulación-pirólisis proporciona una vía versátil para sintetizar diversos catalizadores diatómicos.
Los sitios diatómicos de Fe-Cu ofrecen una vía prometedora para el desarrollo de electrocatalizadores altamente duraderos y eficientes para ORR.
La biblioteca DAC desarrollada desbloquea vías de reacción no convencionales, avanzando en el diseño y la aplicación de electrocatalisadores.

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