Effects of Gas Layer Thickness on Capillary Interactions at Superhydrophobic Surfaces

Strongly attractive forces act between superhydrophobic surfaces across water due to the formation of a bridging gas capillary. Upon separation, the attraction can range up to tens of micrometers as the gas capillary grows, while gas molecules accumulate in the capillary. We argue that most of these...

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Veröffentlicht in:Langmuir : the ACS journal of surfaces and colloids. - 1992. - 40(2024), 9 vom: 05. März, Seite 4801-4810
1. Verfasser: Eriksson, Mimmi (VerfasserIn)
Weitere Verfasser: Claesson, Per M, Järn, Mikael, Wallqvist, Viveca, Tuominen, Mikko, Kappl, Michael, Teisala, Hannu, Vollmer, Doris, Schoelkopf, Joachim, Gane, Patrick A C, Mäkelä, Jyrki M, Swerin, Agne
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2024
Zugriff auf das übergeordnete Werk:Langmuir : the ACS journal of surfaces and colloids
Schlagworte:Journal Article
Beschreibung
Zusammenfassung:Strongly attractive forces act between superhydrophobic surfaces across water due to the formation of a bridging gas capillary. Upon separation, the attraction can range up to tens of micrometers as the gas capillary grows, while gas molecules accumulate in the capillary. We argue that most of these molecules come from the pre-existing gaseous layer found at and within the superhydrophobic coating. In this study, we investigate how the capillary size and the resulting capillary forces are affected by the thickness of the gaseous layer. To this end, we prepared superhydrophobic coatings with different thicknesses by utilizing different numbers of coating cycles of a liquid flame spraying technique. Laser scanning confocal microscopy confirmed an increase in gas layer thickness with an increasing number of coating cycles. Force measurements between such coatings and a hydrophobic colloidal probe revealed attractive forces caused by bridging gas capillaries, and both the capillary size and the range of attraction increased with increasing thickness of the pre-existing gas layer. Hence, our data suggest that the amount of available gas at and in the superhydrophobic coating determines the force range and capillary growth
Beschreibung:Date Revised 09.03.2024
published: Print-Electronic
Citation Status PubMed-not-MEDLINE
ISSN:1520-5827
DOI:10.1021/acs.langmuir.3c03709