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Agua en las superficies de óxido: un complejo de coordinación de la superficie de Triaqua en Co3O4
George Yan1, Tobias Wähler2, Ralf Schuster2
1Department of Chemical and Biomolecular Engineering , University of California, Los Angeles , Los Angeles , California 90095 , United States.
Journal of the American Chemical Society
|March 22, 2019
Resumen
La interacción del agua con las superficies de óxido de cobalto revela nuevas estructuras de hidratación. Esta investigación hace avanzar la comprensión de las superficies de óxido metálico en la catálisis y la electrocatálisis.
Área de la Ciencia:
- Ciencias de la superficie
- Catálisis
- Química computacional
Sus antecedentes:
- La interacción del agua con los óxidos metálicos es crucial para la catálisis heterogénea y la electrocatálisis.
- La comprensión de las estructuras superficiales es clave para controlar la actividad y la estabilidad del material.
Objetivo del estudio:
- Para identificar los motivos estructurales formados por el agua que interactúa con una superficie de óxido de cobalto (Co3O411).
- Caracterizar nuevas estructuras de hidratación en las superficies de óxidos metálicos.
Principales métodos:
- Cálculos de la teoría funcional de la densidad (DFT).
- Espectroscopia de absorción por reflexión infrarroja (IRAS).
Principales resultados:
- Se observaron tres estructuras principales: OD aislado, OD/D2O enlazado con hidrógeno y una nueva estructura de "medio caparazón de hidratación".
- La nueva estructura implica que los iones de superficie Co2+ se unen a tres moléculas de D2O, formando un Co2+ coordinado octaédricamente.
- Esta estructura se propone como un intermediario en la reorganización y disolución de la superficie de óxido.
Conclusiones:
- Se han identificado nuevas estructuras de hidratación en las superficies de Co3O4{111}.
- La estructura de "medio caparazón de hidratación" proporciona nuevas ideas sobre las interacciones agua-óxido.
- Estos hallazgos son relevantes para la comprensión y el diseño de catalizadores de óxidos metálicos y electrocatalizadores.
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