A1 Journal article (refereed)
Droplet slipperiness despite surface heterogeneity at molecular scale (2024)


Lepikko, S., Morais Jaques, Y., Junaid, M., Backholm, M., Lahtinen, J., Julin, J., Jokinen, V., Sajavaara, T., Sammalkorpi, M., Foster, A. S., & Ras, R. H. A. (2024). Droplet slipperiness despite surface heterogeneity at molecular scale. Nature Chemistry, 16(4), 506-513. https://doi.org/10.1038/s41557-023-01346-3


JYU authors or editors


Publication details

All authors or editorsLepikko, Sakari; Morais Jaques, Ygor; Junaid, Muhammad; Backholm, Matilda; Lahtinen, Jouko; Julin, Jaakko; Jokinen, Ville; Sajavaara, Timo; Sammalkorpi, Maria; Foster, Adam S.; et al.

Journal or seriesNature Chemistry

ISSN1755-4330

eISSN1755-4349

Publication year2024

Publication date23/10/2023

Volume16

Issue number4

Pages range506-513

PublisherNature Publishing Group

Publication countryUnited Kingdom

Publication languageEnglish

DOIhttps://doi.org/10.1038/s41557-023-01346-3

Publication open accessOpenly available

Publication channel open accessPartially open access channel

Publication is parallel published (JYX)https://jyx.jyu.fi/handle/123456789/91825

Additional informationPublisher Correction: Droplet slipperiness despite surface heterogeneity at molecular scale. Nature Chemistry (2023), https://doi.org/10.1038/s41557-023-01401-z.


Abstract

Friction determines whether liquid droplets slide off a solid surface or stick to it. Surface heterogeneity is generally acknowledged as the major cause of increased contact angle hysteresis and contact line friction of droplets. Here we challenge this long-standing premise for chemical heterogeneity at the molecular length scale. By tuning the coverage of self-assembled monolayers (SAMs), water contact angles change gradually from about 10° to 110° yet contact angle hysteresis and contact line friction are low for the low-coverage hydrophilic SAMs as well as high-coverage hydrophobic SAMs. Their slipperiness is not expected based on the substantial chemical heterogeneity of the SAMs featuring uncoated areas of the substrate well beyond the size of a water molecule as probed by metal reactants. According to molecular dynamics simulations, the low friction of both low- and high-coverage SAMs originates from the mobility of interfacial water molecules. These findings reveal a yet unknown and counterintuitive mechanism for slipperiness, opening new avenues for enhancing the mobility of droplets.


Keywordssurfacessurface chemistryfrictionslipperinesswater

Free keywordssurface chemistry; wetting


Contributing organizations


Ministry reportingYes

Reporting Year2023

JUFO rating3


Last updated on 2024-14-06 at 23:06