Properties of Ca-rich and Mg-rich carbonate films on dolomite : implications for compositional surface mapping with scanning force microscopy

A self-limited monolayer grown on dolomite (CaMg(CO(3))(2)), showing distinct friction contrast with the substrate as reported earlier using lateral force microscopy, was investigated with in situ atomic force microscopy (AFM) adhesion mapping and force-modulation techniques. Force-modulation micros...

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Détails bibliographiques
Publié dans:Langmuir : the ACS journal of surfaces and colloids. - 1985. - 26(2010), 7 vom: 06. Apr., Seite 4769-75
Auteur principal: Hu, Xiaoming (Auteur)
Autres auteurs: Cubillas, Pablo, Higgins, Steven R
Format: Article en ligne
Langue:English
Publié: 2010
Accès à la collection:Langmuir : the ACS journal of surfaces and colloids
Sujets:Journal Article
Description
Résumé:A self-limited monolayer grown on dolomite (CaMg(CO(3))(2)), showing distinct friction contrast with the substrate as reported earlier using lateral force microscopy, was investigated with in situ atomic force microscopy (AFM) adhesion mapping and force-modulation techniques. Force-modulation microscopy revealed lower stiffness on a Ca-rich film in comparison to that on the dolomite surface. The friction contrast therefore results from a larger tip-surface contact area when the AFM probe is in contact with the Ca-rich film as opposed to the contact area with dolomite. The Ca-rich film also exhibited a slightly higher adhesion than did the dolomite substrate; however, the critical shear stresses for the two tip-surface contacts were indistinguishable. A comparative study with a Mg-rich film did not yield noticeable force modulation contrast, indicating similar surface stiffness of the film and the dolomite surface. The similarity in these stiffness quantities was further corroborated by friction-load data that demonstrated similar friction forces on the two surfaces. The previously reported film strain in the Ca-rich system is likely linked to the lower stiffness observed, with both of these properties related to the Ca/Mg composition of the film
Description:Date Completed 21.06.2010
Date Revised 30.03.2010
published: Print
Citation Status PubMed-not-MEDLINE
ISSN:1520-5827
DOI:10.1021/la9035425