Atomic-Scale View of the Oxidation and Reduction of Supported Ultrathin FeO Islands
| Autor: | Kræn C. Adamsen, Lutz Lammich, Jeppe V. Lauritsen, Stefan Wendt, Yijia Li |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2019 |
| Předmět: |
iron oxide
Materials science Hydrogen Iron oxide General Physics and Astronomy chemistry.chemical_element 02 engineering and technology dissociation 010402 general chemistry Photochemistry 01 natural sciences Redox Oxygen Dissociation (chemistry) law.invention Catalysis chemistry.chemical_compound law O adatom dislocation lines General Materials Science catalysis Bilayer General Engineering 021001 nanoscience & nanotechnology 0104 chemical sciences chemistry STM movies Scanning tunneling microscope 0210 nano-technology |
| Zdroj: | Li, Y, Adamsen, K C, Lammich, L, Lauritsen, J V & Wendt, S 2019, ' Atomic-Scale View of the Oxidation and Reduction of Supported Ultrathin FeO Islands ', ACS Nano, vol. 13, no. 10, pp. 11632-11641 . https://doi.org/10.1021/acsnano.9b05470 |
| DOI: | 10.1021/acsnano.9b05470 |
| Popis: | By means of scanning tunneling microscopy (STM) measurements, we studied in situ the oxidation and reduction of FeO bilayer islands on Au(111) by oxygen (O2) and hydrogen (H2), respectively. The FeO islands respond very dynamically toward O2, with the coordinatively unsaturated ferrous (CUF) sites at the island edges being essential for O2 dissociation and O atom incorporation. An STM movie obtained during oxidation reveals how further O2 molecules can dissociate after the consumption of all initially existing CUF sites through the formation of new CUF sites. In contrast, we found that H2 molecules only dissociate when vibrationally excited through the ion gauge and only at the basal plane of FeO islands, implying that the CUF sites are not relevant for H2 dissociation. Our STM results reveal how excess O atoms are incorporated and released in O2 and H2 and thus shed light onto the stability of inverse catalysts during a catalyzed reaction. |
| Databáze: | OpenAIRE |
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