Pressure-sensitive conversions between Cassie and Wenzel wetting states on a nanocorrugated surface

Reversible Surface Energy Storage in Molecular-Scale Porous Materials

“…In contrast to monodisperse samples, this feature leads to multi-step liquid uptake and expulsion processes or continuous transitions with finite slopes of intrusion and expulsion branches constituting the wetting/dewetting cycle. In view of weak correlations [41][42][43] between intrusion/expulsion events in distinct pores, results for a spectrum of pore sizes should enable predictions for water content in a polydisperse absorbent as a linear superposition of fractional contributions from pores of different sizes. In a general case, a normalized pore size distribution function p(h), where p(h)dh represents the fraction of pores of widths between h and h + dh, determines the volume change of the bulk phase associated with the absorption of N( P b ) molecules in the material at pressure P b , ∆V(P b ) = −V(P b )N(P b ), where V(P b ) is the partial molar volume in bulk water at pressure P b , N(P b ) = ∞ 0 N(P b , h)p(h)dh, and N(P b , h) denotes the average number of absorbed molecules inside a pore of width h at bulk pressure P b.…”