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Exploración atómica del reordenamiento estructural impulsado por la fluoración de los electrocatalizadores de carbono

Yang Li^1,2, Zhen Cao², Cailing Chen¹

¹Center for Renewable Energy and Storage Technologies (CREST), Physical Science and Engineering Division, King Abdullah University of Science and Technology, Thuwal 23955-6900, Kingdom of Saudi Arabia.

Journal of the American Chemical Society

|August 16, 2025

Resumen

El diseño de electrocatalizadores de carbono avanzados para reacciones de reducción de oxígeno (ORR) es clave para la energía renovable. Este estudio revela cómo la disposición de átomos de flúor y nitrógeno en materiales de carbono crea sitios altamente activos, mejorando el rendimiento de ORR.

Área de la Ciencia:

Ciencias de los materiales
La electroquímica
Catálisis

Sus antecedentes:

La disposición de los átomos en los electrocatalizadores de carbono es crítica para las reacciones de reducción de oxígeno (ORR).
El diseño de electrocatalizadores de alto rendimiento está limitado por los desafíos sintéticos y la comprensión de la formación de la fase catalítica.

Objetivo del estudio:

Obtener información a nivel atómico sobre el origen de sitios altamente activos para las ORR.
Diseñar y optimizar electrocatalizadores basados en carbono sin metales.

Principales métodos:

Síntesis de una matriz de carbono decorada con flúor (F) y nitrógeno (N).
Inducir el reordenamiento estructural del pirrólico-N al grafítico-N y al nitrógeno pirídico.
Investigación de los efectos sinérgicos de múltiples dopantes y de las modificaciones de la estructura electrónica.

Principales resultados:

La introducción de flúor reorganiza la configuración de nitrógeno para que sea predominantemente piridina-N y grafita-N.
Los efectos sinérgicos de F, piridino-N y grafito-N localizan la estructura electrónica.
Las configuraciones asimétricas de piridina-N y grafita-N muestran el sobrepotencial de ORR teórico más bajo.
El catalizador F@NC optimizado demuestra una excelente actividad de reducción de oxígeno.

Conclusiones:

La disposición atómica, en particular las configuraciones F y N, es crucial para la actividad ORR.
Este trabajo proporciona una base para el diseño racional de electrocatalizadores de carbono sin metal para ORR.

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