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Why is a noble metal catalytically active? The role of the O-Ag interaction in the function of silver as an oxidation catalyst

Wei-Xue Li·Catherine Stampfl·Matthias Scheffler
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Abstract

Extensive density-functional theory calculations, and taking into account temperature and pressure, affords a comprehensive picture of the behavior and interaction of oxygen and Ag(111), and provides valuable insight into the function of silver as an oxidation catalyst. The obtained phase-diagram reveals the most stable species present in a given environment and thus identifies (and excludes) possibly active oxygen species. In particular, for the conditions of ethylene epoxidation, a thin oxide-like structure is most stable, suggesting that such atomic O species are actuating the catalysis, in contrast to hitherto proposed molecular-like species.

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Wei-Xue Li, Catherine Stampfl, Matthias Scheffler. 2003-05-13. Why is a noble metal catalytically active? The role of the O-Ag interaction in the function of silver as an oxidation catalyst. https://doi.org/10.1103/physrevlett.90.256102

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