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Medir y relacionar las estructuras electrónicas de materiales catalíticos no respaldados por el modelo con su

Eranda Nikolla¹, Johannes Schwank, Suljo Linic

¹Department of Chemical Engineering, University of Michigan, Ann Arbor, Michigan 48109-2136, USA.

Journal of the American Chemical Society

|February 10, 2009

Resumen

Este estudio vincula los cambios de estructura electrónica en los catalizadores soportados a su rendimiento. La aleación crea nuevos estados electrónicos, no redistribución de carga, lo que afecta la actividad catalítica.

Área de la Ciencia:

Ciencia de los materiales Ciencia de los materiales.
La catálisis es la catálisis.
Ciencias de la superficie Ciencias de la superficie.

Sus antecedentes:

Las relaciones estructura-rendimiento son clave para el descubrimiento de catalizadores.
La teoría de la banda d conecta la estructura electrónica metálica con la actividad catalítica.
Los datos experimentales sobre catalizadores no modelo son limitados.

Objetivo del estudio:

Relacionar las estructuras electrónicas de los catalizadores no modelo con el rendimiento.
Investigar los cambios en la estructura electrónica durante la aleación.
Desarrollar un marco para predecir los cambios de banda d y el comportamiento catalítico.

Principales métodos:

Estudió los catalizadores soportados y la formación de aleaciones superficiales.
Se midieron cambios en la estructura electrónica cercanos al nivel de Fermi.
La estructura electrónica correlacionada cambia con el rendimiento catalítico.

Principales resultados:

Los pequeños cambios en la estructura electrónica de los catalizadores no modelo son medibles y están vinculados al rendimiento.
Los desplazamientos del centro de la banda d en las aleaciones surgen de nuevos estados electrónicos, no de la redistribución de carga.
La aleación mantiene constantes las cuentas de electrones/agujeros d en los elementos constituyentes.

Conclusiones:

Los estados electrónicos inducidos por la aleación impulsan los cambios de banda d.
Se proporciona un marco para predecir los desplazamientos de la banda d y las propiedades químicas de las aleaciones.
Este trabajo une la teoría y el experimento para la optimización de catalizadores.

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