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DOE OSTI · 1870872

Atomic-Scale Structure of Chemically Distinct Surface Oxygens in Redox Reactions

Das, Anusheela·Park, Haesun·Chen, Yanna·Choudhury, Devika·Lee, Tien-Lin·Elam, Jeffrey W.·Zapol, Peter·Bedzyk, Michael J.
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Abstract

During redox reactions, oxide-supported catalytic systems undergo structural and chemical changes. Improving subsequent catalytic properties requires an understanding of the atomic-scale structure with chemical state specificity under reaction conditions. For the case of 1/2 monolayer vanadia on α-TiO 2 (110), we use X-ray standing wave (XSW) excited X-ray photoelectron spectroscopy to follow the redox induced atomic positional and chemical state changes of this interface. Furthermore, while the resulting XSW 3D composite atomic maps include the Ti and O substrate atoms and V surface atoms, our focus in this report is on the previously unseen surface oxygen species with comparison to density functional theory predictions.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYCompositesDFT calculationsOxidesOxygenRedox reactions

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Das, Anusheela, Park, Haesun, Chen, Yanna, Choudhury, Devika, Lee, Tien-Lin, Elam, Jeffrey W., Zapol, Peter, Bedzyk, Michael J.. 2021-10-21. Atomic-Scale Structure of Chemically Distinct Surface Oxygens in Redox Reactions. https://doi.org/10.1021/jacs.1c07926

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