Dip-Coating of a Nanometer-Thick Fluorinated Imidazolium Ionic Liquid: Layer Structure, Formation Mechanism and Wetting Behavior

= 0.99), consistent with Landau-Levich hydrodynamic theory for dilute solutions. These results demonstrate that HFILOH film formation in dip-coating is governed by the dual mechanisms of site-limited adsorption and viscous flow entrainment. Contact angle measurements reveal hydrophilic-oleophobic wetting behavior, with hexadecane contact angles remaining consistently high (∼70-75°) while water contact angles increase modestly from ∼ 30° to ∼ 40° with dwell time, indicating time-dependent molecular reorganization and preferential orientation of fluorinated chains at the HFILOH-air interface. This interpretation of a fluorine-rich outer surface is in good agreement with angle-resolved X-ray photoelectron spectroscopy and dynamic contact angle measurements previously reported for nanometer-thick HFILOH coatings on silica, which directly show fluorinated segments enriched at the film-air interface and stable hydrophilic-oleophobic wetting. Together, these findings provide mechanistic insight into the structure-property relationships controlling ionic liquid nanofilm functionality and establish HFILOH as a promising candidate for applications like antifogging, self-cleaning, and oil-water separation.