Wetting Transition on Liquid-Repellent Surfaces Probed by Surface Force Measurements and Confocal Imaging

Eriksson, MimmiRISE,KTH,Yt- och korrosionsvetenskap,RISE Res Inst Sweden, SE-11486 Stockholm, Sweden,Yta, process och formulering,KTH Royal Institute of Technology, Sweden (författare)

QC 20191220
Superhydrophobic surfaces in the Cassie-Baxter wetting state retain an air layer at the surface which prevents liquid water from reaching into the porous surface structure. In this work we explore how addition of ethanol, which reduces the surface tension, influences the wetting properties of superhydrophobic and smooth hydrophobic surfaces. Wetting properties are measured by dynamic contact angles, and the air layer at the superhydrophobic surface is visualized by laser scanning confocal microscopy. Colloidal probe atomic force microscopy measurements between a hydrophobic microsphere and the macroscopic surfaces showed that the presence of ethanol strongly affects the interaction forces. When the macroscopic surface is superhydrophobic, attractive forces extending up to a few micrometers are observed on retraction in water and in 20 vol % ethanol, signifying the presence of a large and growing gas capillary. Submicrometer attractive forces are observed between the probe particle and a smooth hydrophobic surface, and in this case a smaller gas capillary is formed. Addition of ethanol results in markedly different effects between superhydrophobic and hydrophobic surfaces. In particular, we show that the receding contact angle on the superhydrophobic surface is of paramount importance for describing the interaction forces.

Claesson, Per M.RISE,KTH,Yt- och korrosionsvetenskap,RISE Res Inst Sweden, SE-11486 Stockholm, Sweden,Yta, process och formulering,KTH Royal Institute of Technology, Sweden(Swepub:kth)u15tzvsb (författare)
Järn, MikaelRISE,Yta, process och formulering(Swepub:ri)MikaelJa@ri.se (författare)
Tuominen, MikkoRISE,Yta, process och formulering (författare)
Wallqvist, VivecaRISE,Yta, process och formulering(Swepub:ri)VivecaWa@ri.se (författare)
Schoelkopf, JoachimOmya Int AG, CH-4665 Oftringen, Switzerland.,Omya International AG, Switzerland (författare)
Gane, Patrick A. C.Aalto Univ, Sch Chem Engn, Dept Bioprod & Biosyst, FI-00076 Aalto, Finland.,Aalto University, Finland (författare)
Swerin, AgneKTH,Yt- och korrosionsvetenskap,KTH Royal Institute of Technology, Sweden(Swepub:kth)u1463w2g (författare)
KTHYt- och korrosionsvetenskap (creator_code:org_t)

Av författaren/redakt...: Eriksson, Mimmi; Claesson, Per M.; Järn, Mikael; Tuominen, Mikko; Wallqvist, Vivec ...; Schoelkopf, Joac ...; visa fler...; Gane, Patrick A. ...; Swerin, Agne; visa färre...

Om ämnet

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.