Prewetting transition influenced by layeringlike transitions at a binary liquid/solid interface

Abstract

Articles you may be interested inThe isotropic-nematic and nematic-nematic phase transition of binary mixtures of tangent hard-sphere chain fluids: An analytical equation of stateThe prewetting transition in the silica-water-2,5-dimethylpyridine system has been studied through the adsorption isotherms. Steep wave shapes for these isotherms lead to the conclusion of alternate solid and liquid surface demixing very close to bulk coexistence and wetting temperature. Liquid demixing has the generic aspects of prewetting. An empirical model for demixings, surface phase diagrams in several representations, and critical end points are discussed, as well as the phenomena universality.

Impact of Bulk Phase Transitions and Wetting Transitions on Adsorption Isotherms in Binary Systems in Contact with Solid

“…In a second step, the isotherm's shape can be analyzed. In concentrated solutions, the negative slopes can be shown to correspond to the achieved surface enrichment by at least one layer (6,11), and these parts of waves have the same behavior as the plateaus (i.e., shrinking when x 2 tends toward its coexistence value and disappearance close to a bulk critical end point); consequently, the layering is an intrinsic behavior of the system and this is why it persists in concentrated solutions. The positive slopes are caused by the enrichment of the surface with water when one is going to bulk demixing, because minimal ⌫ 21 are negative.…”

“…Starting from bulk coexistence, the first is caused by layering (i.e., surface liquid-solid demixing), the second by prewetting (i.e., surface liquid-liquid demixing), and so on. All this happens as though the surface system oscillated on a surface phase diagram showing a eutectic curve interrupted by a liquid-liquid demixing loop (11). In Figs.…”

“…When T 3 T C , the step width tends to zero. Between 40 and 46°C, the points cross the ordinary curve (11).…”

“…Experimental surface phase diagram constituted from x 2 ϭ f( x 2 ) adsorption isotherms (5,11), corresponding to a liquid-liquid surface demixing. x 2 is calculated according to a layering model for ⌫ 2 (5); values have been selected on the second vertical segment appearing on isotherms at 40, 42, 44, and 46°C (Fig.…”

Wetting and prewetting of water on top of a single sheet of hexagonal boron nitride

“…The temperature at which the thin layer starts to form is called the wetting temperature (T w ). At higher temperatures, we observe a different phenomenon: the difference in densities between the thin and thick layers decreases until it disappears at a temperature called the critical prewetting temperature (T pw ) [4,5]. For T T pw there is a continuum layer formation upon an increase in density, instead of a first-order phase transition.…”