Regensburg 2019 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
DY: Fachverband Dynamik und Statistische Physik
DY 13: Wetting, Fluidics and Liquids at Interfaces and Surfaces (joint session CPP/DY)
DY 13.2: Talk
Tuesday, April 2, 2019, 09:45–10:00, H13
Molecular Hydrophobicity at a Macroscopic Hydrophilic Surface — •Jenee D. Cyran1, Michael Donovan1, Doris Vollmer1, Flavio Siro Brigiano2, Simone Pezzotti2, Daria R. Galimberti2, Marie-Pierre Gaigeot2, Mischa Bonn1, and Ellen H.G. Backus1 — 1Max Planck Institute for Polymer Research, Mainz, Germany — 2LAMBRE, Univ Every, Universite Paris-Saclay, Evry, France
Chemical and physical interactions between water and silicates are ubiquitous and relevant for geochemistry and industrial processes, including chromatography, oil extraction and coatings. Characterizing the silica/water interface is important to not only understand the fundamental properties for natural occurring processes but also to improve existing technologies, such as silica coatings, which rely on wettability and thermal-resistant properties to remain effective. At the silica/water interface, we compare the microscopic water organization, from both surface sensitive vibrational sum frequency generation experiments and molecular dynamics simulations, to macroscopic information about the hydrophobicity obtained from contact angle measurements. At the microscopic level, weakly hydrogen-bonded OH groups, typical for hydrophobic interfaces, are observed that originate from water molecules interacting with hydrophobic sites of the silica surface. Surprisingly, we observe the presence of hydrophobic water at a macroscopically hydrophilic water surface.