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Aceleración de la electrorreducción de nitrato a amoníaco a través de las interacciones de soporte metálico en

Jiangnan Lv¹, Qianwen Yang¹, Tingting Liang¹

¹Research Institute of Materials Science of Shanxi Normal University & Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education, Taiyuan 030031, China.

Journal of the American Chemical Society

|July 22, 2025

Resumen

Este estudio introduce un nuevo catalizador Ni-WS2 para la reacción de reducción de nitrato electrocatalítico (NO3-RR), mejorando significativamente la síntesis de amoníaco (NH3) y el tratamiento de aguas residuales. El catalizador presenta una alta eficiencia y estabilidad, superando las limitaciones de los dicalcogenuros de metales de transición (TMD) tradicionales.

Área de la Ciencia:

Electroquímica y ciencias de los materiales
Catálisis para la síntesis química sostenible

Sus antecedentes:

La reacción de reducción de nitrato electrocatalítico (NO3-RR) es crucial para el tratamiento de aguas residuales y la producción de amoníaco (NH3).
Los dicalcogenuros de metales de transición bidimensionales (TMD) son prometedores como catalizadores, pero tienen una cinética y una estabilidad deficientes.
La interacción de soporte metálico (MSI) es una estrategia clave para mejorar el rendimiento del catalizador.

Objetivo del estudio:

Diseñar y sintetizar un nuevo catalizador Ni-WS2 impulsado por MSI para mejorar el NO3-RR.
Investigar el rendimiento del catalizador en términos de eficiencia, tasa de rendimiento y estabilidad.
Aclarar el papel del MSI en la mejora de la actividad catalítica a través de cálculos teóricos.

Principales métodos:

Se empleó una estrategia de dos pasos para sintetizar el catalizador Ni-WS2.
Se evaluó el rendimiento electrocatalítico para el NO3-RR, incluida la eficiencia Faradaic y la tasa de rendimiento de NH3.
La estabilidad se probó en un conjunto de electrodos de membrana (MEA) durante un funcionamiento prolongado.
Se utilizaron cálculos de la teoría funcional de la densidad (DFT) para comprender los efectos del MSI.

Principales resultados:

El catalizador Ni-WS2 logró una alta eficiencia Faradaic del 91,7% para el NO3-RR y una tasa de rendimiento de NH3 de 23,3 mg h-1 cm-2.
Se demostró una estabilidad excepcional, manteniendo ≈32 mg h-1 cm-2 de producción de NH3 durante 100 horas en un MEA.
Los cálculos de DFT confirmaron que MSI optimiza la distribución de la carga y reduce la barrera energética para la etapa de determinación de la tarifa.
Una batería de Zn-NO3 utilizando el cátodo Ni-WS2 mostró un rendimiento notable.

Conclusiones:

El catalizador Ni-WS2 impulsado por MSI ofrece una solución altamente eficiente y estable para la reducción electrocatalítica de nitratos.
Este trabajo establece una estrategia de síntesis viable para electrocatalizadores avanzados basados en TMD a través de la modulación MSI.
Los resultados allanan el camino para aplicaciones prácticas en la síntesis sostenible de amoníaco y la remediación de aguas residuales.

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