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Ammonia Synthesis at Low Pressure
Published on: August 23, 2017
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Diseño de catalizador de cribado de silicio de alto rendimiento basado en el mecanismo QM para la síntesis de
Qi An1,2, Yidi Shen2, Alessandro Fortunelli1,3
1Materials and Process Simulation Center (MSC) , California Institute of Technology , Pasadena , California 91125 , United States.
Journal of the American Chemical Society
|November 28, 2018
Resumen
Desarrollamos un método jerárquico de cribado de alto rendimiento (HHTS) para el diseño de catalizadores. Este enfoque acelera el descubrimiento de los dopantes óptimos para la síntesis de amoníaco, prediciendo un aumento de 3,3 veces en la frecuencia de rotación con el dopaje Rh.
Área de la Ciencia:
- Ciencias de la catálisis
- Ciencias de los materiales
- Química computacional
Sus antecedentes:
- El diseño de catalizadores para reacciones complejas es desafiante y computacionalmente costoso.
- El proceso Haber-Bosch para la síntesis de amoníaco requiere catalizadores eficientes.
Objetivo del estudio:
- Desarrollar y validar un enfoque jerárquico de cribado de alto rendimiento (HHTS) para el diseño acelerado de catalizadores.
- Identificar los dopantes óptimos para los catalizadores a base de hierro para mejorar la síntesis de amoníaco.
Principales métodos:
- Las redes de reacción derivadas de la mecánica cuántica (QM) se simplificaron para centrarse en los pasos que determinan la velocidad.
- Se empleó una estrategia de selección jerárquica, priorizando las reacciones mediante barreras de energía libre.
- El enfoque redujo el esfuerzo computacional en un 99% para el cribado inicial de los dopantes.
Principales resultados:
- Se examinaron 34 sustancias dopantes candidatas para la síntesis de amoníaco a base de hierro.
- Identificó un subconjunto de promesas incluyendo Rh, Pt, Pd y Cu.
- Se prevé que el catalizador de hierro con dopaje Rh aumente la frecuencia de rotación de la síntesis de amoníaco (TOF) en ~ 3,3 veces.
Conclusiones:
- El enfoque HHTS acelera significativamente el diseño de catalizadores para sistemas complejos.
- Se prevé que el dopaje Rh sea altamente efectivo para mejorar la síntesis de amoníaco a base de hierro.
- Este método validado ofrece una vía computacionalmente eficiente para descubrir catalizadores mejorados.
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