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Catálisis en cascada sobre catalizadores duales de iridio-tungsteno para mejorar la oxidación selectiva de amoniaco

Tingxu Chen^1,2, Diru Liu^2,3, Mengyuan Zhang^2,3

¹College of Environmental Science and Engineering, Beijing Forestry University, Beijing, China.

Nature communications

|December 17, 2025

Resumen

Los catalizadores duales con sitios integrados de iridio y tungsteno oxidan selectivamente el amoniaco. Esta estrategia de átomos duales mejora la actividad catalítica y la selectividad, ofreciendo un enfoque prometedor para el control de la contaminación.

Área de la Ciencia:

Catálisis
Ciencia de materiales
Química ambiental

Sus antecedentes:

El compromiso entre actividad y selectividad es un desafío persistente en catálisis.
Los catalizadores de átomos duales (DAC) ofrecen efectos sinérgicos de sitios activos distintos, mejorando la selectividad en catálisis en cascada.

Objetivo del estudio:

Desarrollar catalizadores duales Ir-Wx/CeO2 para la oxidación catalítica selectiva de amoniaco.
Investigar los efectos sinérgicos de los sitios integrados de oxidación (Ir) y reducción (W).

Principales métodos:

Síntesis y caracterización de catalizadores Ir-Wx/CeO2.
Estudios operando y cálculos teóricos para dilucidar mecanismos de reacción.
Evaluación del rendimiento catalítico en la oxidación de amoniaco.

Principales resultados:

Se incrustaron átomos de Ir en planos de CeO2 y se anclaron sitios de W en la superficie, formando estructuras de dímeros Ir-W.
Se identificó un mecanismo sinérgico que involucra la oxidación de NH3 en Ir y la reducción catalítica selectiva (SCR) en W.
El catalizador Ir-W7/CeO2 logró una actividad >=92% a 200°C y una selectividad >=92% a 300°C.

Conclusiones:

Los dímeros de átomos duales Ir-W sobre CeO2 catalizan eficazmente la oxidación selectiva de amoniaco.
La estrategia de átomos duales demuestra una amplia aplicabilidad para otras combinaciones de metales (por ejemplo, Ir-Mo, Ir-Nb).
Los DAC muestran un potencial significativo para el diseño de catalizadores para reacciones en cascada y aplicaciones ambientales.

Palabras clave:

Catálisis Oxidación selectiva de amoniaco Catalizadores de átomos duales Iridio-Tungsteno Control de la contaminación

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