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Conversión sinérgica de nitrato a gas nitrógeno mediante un sistema fotoelectrocatalítico con radicales atómicos de

Yongjie Wang¹, Ying Tao¹, Chi Zhang¹

¹The Education Ministry Key Lab of Resource Chemistry, Shanghai Key Laboratory of Rare Earth Functional Materials, and Shanghai Frontiers Science Center of Biomimetic Catalysis, Joint International Research Laboratory of Resource Chemistry of Ministry of Education, Shanghai Normal University, Shanghai, China.

Advanced science (Weinheim, Baden-Wurttemberg, Germany)

|December 24, 2025

Resumen

Este estudio presenta un novedoso sistema fotoelectrocatalítico para la eliminación eficiente de nitratos (NO₃^-), convirtiéndolos en gas nitrógeno (N₂) con una selectividad cercana al 100%. El proceso utiliza radicales reactivos de hidrógeno y cloro para prevenir la contaminación secundaria.

Área de la Ciencia:

Química Ambiental; Ciencia de Materiales; Electroquímica

Sus antecedentes:

La contaminación por nitratos en las aguas residuales provoca eutrofización.
La reducción selectiva de los nitratos a gas nitrógeno es crucial para la protección del medio ambiente.
Las tecnologías existentes a menudo enfrentan desafíos con la contaminación secundaria y la eficiencia.

Objetivo del estudio:

Desarrollar un novedoso sistema fotoelectrocatalítico para la eliminación de nitratos altamente eficiente y selectiva.
Investigar un proceso sinérgico de reducción-oxidación utilizando radicales reactivos.
Minimizar la formación de intermedios dañinos como el amonio (NH₄⁺).

Principales métodos:

Se diseñó un sistema fotoelectrocatalítico utilizando CuO-Fe₃O₄/espuma de níquel como cátodo y arreglos de nanotubos de TiO₂ como fotocátodo.
El sistema empleó una estrategia de relevo que involucra radicales atómicos de hidrógeno (H*) y cloro (Cl•) reactivos.
Se realizaron estudios mecanísticos para comprender las vías de reacción y la formación de intermedios.

Principales resultados:

Se logró una tasa de eliminación de nitratos (NO₃^-) del 97,4% con una selectividad cercana al 100% para el gas nitrógeno (N₂).
Se suprimió eficazmente la acumulación del intermedio amonio (NH₄⁺).
El sistema demostró un rendimiento superior en comparación con métodos reportados anteriormente.

Conclusiones:

El proceso de reducción-oxidación sinérgico desarrollado ofrece una estrategia sostenible para la eliminación de nitratos.
Esta tecnología muestra una gran promesa para el tratamiento de aguas residuales y ambientes acuáticos contaminados por nitratos.
La estrategia de relevo utilizando radicales de hidrógeno y cloro atómicos es efectiva para la conversión completa de nitratos a N₂.

Palabras clave:

eliminación de nitratos selectividad de gas nitrógeno radicales reactivos de hidrógeno y cloro reacción de relevo en tándem de radicales tratamiento de aguas residuales

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