Abstract
The spatial distribution of potassium on an Rh(110) surface during the catalytic O2+H2 reaction is investigated employing photoelectron emission microscopy (PEEM) and scanning photoelectron microscopy (SPEM) as spatially resolving in situ methods. Depending on the reaction conditions, potassium condenses reversibly into macroscopic islands where it is coadsorbed with oxygen. Mass transport of potassium with the reaction fronts is observed. Differences in the mobility and in the bonding strength of potassium on the “reduced” and on the oxygen-covered surface areas are considered to be the key factors for the formation of the stationary concentration patterns.
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Marbach, H., Günther, S., Luerßen, B. et al. Selforganization of Alkali Metal on a Catalytic Metal Surface. Catalysis Letters 83, 161–164 (2002). https://doi.org/10.1023/A:1021073711705
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DOI: https://doi.org/10.1023/A:1021073711705