Evidence for potassium carbonate crystallites on air-cleaved mica surfaces

Air-cleaved mica surfaces exhibit a high density of nanometer or micrometer size particles that have been ascribed to potassium carbonate formed as a reaction product of carbonaceous gases with potassium ions. Unambiguous evidence for this assignment has, however, never been presented. We study air-...

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Veröffentlicht in:Langmuir : the ACS journal of surfaces and colloids. - 1992. - 25(2009), 18 vom: 15. Sept., Seite 10764-7
1. Verfasser: Ostendorf, Frank (VerfasserIn)
Weitere Verfasser: Schmitz, Carsten, Hirth, Sabine, Kühnle, Angelika, Kolodziej, Jacek J, Reichling, Michael
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2009
Zugriff auf das übergeordnete Werk:Langmuir : the ACS journal of surfaces and colloids
Schlagworte:Journal Article
Beschreibung
Zusammenfassung:Air-cleaved mica surfaces exhibit a high density of nanometer or micrometer size particles that have been ascribed to potassium carbonate formed as a reaction product of carbonaceous gases with potassium ions. Unambiguous evidence for this assignment has, however, never been presented. We study air-cleaved mica surfaces by high-resolution noncontact atomic force microscopy (NC-AFM) in ultrahigh vacuum to reveal the detailed structure of such precipitates on the surface. Among a large number of irregularly shaped surface structures, we find flat, hexagonally shaped islands exhibiting two different patterns on their surfaces, namely a rectangular atomic corrugation pattern and a hexagonal moire structure. The unit cell of the rectangular pattern corresponds to the dimensions of the potassium carbonate bulk structure and is found on high crystallites. The moire structure solely appears on very flat islands and is caused by the interference of the potassium carbonate lattice periodicity and the lattice periodicity of the underlying mica substrate. Both results strongly point to the presence of potassium carbonate crystallites on air-cleaved mica surfaces
Beschreibung:Date Completed 04.12.2009
Date Revised 08.09.2009
published: Print
Citation Status PubMed-not-MEDLINE
ISSN:1520-5827
DOI:10.1021/la901311k