Wetting transition of a binary liquid mixture at a solid boundary
| Autor: | J. Peisl, Uwe Klemradt, Marcus Huber, Anton Plech |
|---|---|
| Rok vydání: | 2000 |
| Předmět: |
Materials science
Silicon General Physics and Astronomy chemistry.chemical_element Substrate (electronics) Condensed Matter::Soft Condensed Matter Condensed Matter::Materials Science chemistry.chemical_compound Adsorption chemistry Wetting transition Chemical physics Slab Wetting Perfluoromethylcyclohexane Wetting layer |
| Zdroj: | Europhysics Letters (EPL). 49:583-589 |
| ISSN: | 1286-4854 0295-5075 |
| DOI: | 10.1209/epl/i2000-00190-3 |
| Popis: | We present the observation of a first-order wetting transition of the binary liquid mixture 2-propanol and perfluoromethylcyclohexane at a liquid-solid interface, where one component (2-propanol) of the gravity-separated mixture is selectively adsorbed on the surface of a silicon substrate. The system undergoes a wetting transition from a thin adsorbed film to a macroscopic wetting layer at Tw = 50.6 °C with pronounced premonitory growth of the adsorbed film. The microscopic density profile of the prewetting film is derived from fits to temperature-dependent X-ray reflectivity measurements. Our experimental data clearly indicate a film structure dominated by strong density gradients, which is in contrast to the frequently used "homogeneous slab" models, but confirms density functional calculations. Time-resolved measurements during equilibration reveal new details of the adsorption film growth process, in particular the existence of separate density and thickness growth regimes. |
| Databáze: | OpenAIRE |
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