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Ammonia Synthesis at Low Pressure
Published on: August 23, 2017
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Electrosíntesis de amoníaco con alta selectividad bajo condiciones ambientales a través de una estrategia de
Gao-Feng Chen1, Xinrui Cao2, Shunqing Wu2
1School of Chemistry and Chemical Engineering, South China University of Technology , Guangzhou 510640, China.
Journal of the American Chemical Society
|July 12, 2017
Resumen
Los iones de litio incorporados en un catalizador de N-etilbenceno-1,2,4,5-tetracarboxílico aumentan dramáticamente la selectividad de la reacción de electrorreducción del nitrógeno (NRR). Esta estrategia retrasa la evolución del hidrógeno y facilita la adsorción de nitrógeno para mejorar el rendimiento de la NRR.
Área de la Ciencia:
- La electroquímica
- Ciencias de los materiales
- Catálisis
Sus antecedentes:
- La reacción de electrorreducción de nitrógeno (NRR) es crucial para la síntesis sostenible de amoníaco.
- El logro de una alta selectividad en NRR en condiciones ambientales sigue siendo un desafío importante.
- El desarrollo de catalizadores eficientes para la RRN es esencial para la producción de energía renovable y fertilizantes.
Objetivo del estudio:
- Informar sobre el descubrimiento de una mayor selectividad de la NRR utilizando un nuevo catalizador.
- Investigar el mecanismo detrás de la mejora del rendimiento de la NRR.
- Proporcionar información sobre el diseño racional de los catalizadores NRR selectivos.
Principales métodos:
- Evaluación electroquímica del rendimiento del catalizador.
- Cálculos de la teoría funcional de la densidad (DFT) para dilucidar el mecanismo de reacción.
- Síntesis y caracterización del poli (N-etilbenceno-1,2,4,5-diimida tetracarboxílica) (PEBCD) con incorporación de Li+.
Principales resultados:
- Se ha demostrado una gran mejora de la selectividad del NRR en condiciones ambientales.
- Se identificó la asociación de Li+ con átomos de oxígeno en PEBCD como clave para retardar la reacción de evolución del hidrógeno (HER).
- Se observó una adsorción facilitada de N2 y se propuso un mecanismo de hidrogenación alterno "[O-Li+]·N2-Hx".
Conclusiones:
- La incorporación de Li+ a escala atómica en el PEBCD es una estrategia eficaz para aumentar la selectividad de la NRR.
- Los hallazgos ofrecen nuevos conocimientos sobre el diseño de catalizadores para la electrorreducción selectiva del nitrógeno.
- Este enfoque allana el camino para el desarrollo de catalizadores NRR altamente selectivos para aplicaciones prácticas.
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