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Reducción altamente selectiva y fácil de NO2 a NO a temperaturas criogénicas en oro precobrado con hidrógeno
Ming Pan1, Hyung Chul Ham, Wen-Yueh Yu
1Department of Chemical Engineering, Center for Nano and Molecular Science and Technology, Texas Materials Institute, Austin, Texas 78712-0231, United States.
Journal of the American Chemical Society
|December 13, 2012
Resumen
Los catalizadores de oro hidrogenado reducen eficientemente el dióxido de nitrógeno (NO2) a óxido nítrico (NO) a bajas temperaturas. Este estudio revela el oro.
Área de la Ciencia:
- Química de las superficies.
- La catálisis es la catálisis.
- Ciencia de los materiales Ciencia de los materiales.
Sus antecedentes:
- Los catalizadores de oro son conocidos por la hidrogenación, pero carecen de estudios fundamentales de la química de la superficie.
- La reducción de dióxido de nitrógeno (NO2) es crucial en varios procesos químicos.
Objetivo del estudio:
- Para investigar la reducción parcial de NO2 a NO en un modelo de catalizador de oro.
- Para entender la química superficial fundamental de la hidrogenación de NO2 en el oro.
Principales métodos:
- Investigación experimental a 77 K en el vacío.
- Cálculos de la Teoría Funcional de la Densidad (DFT).
- Espectroscopia infrarroja de reflexión y absorción (RAIRS).
Principales resultados:
- 100% de conversión y selectividad para la reducción de NO2 a NO por debajo de 120 K.
- Identificación de HNO2 y N2O3 como intermediarios clave.
- La formación de los intermedios depende de la concentración de hidrógeno en la superficie.
Conclusiones:
- El oro exhibe una alta actividad catalítica para la hidrogenación de NO2 a NO.
- La concentración de hidrógeno en la superficie influye críticamente en las vías de reacción.
- El estudio proporciona información fundamental sobre la reducción de NO2 catalizada por el oro.
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