Filling, depinning, unbinding: Three adsorption regimes for nanocorrugated substrates.

0531839 - ÚCHP 2021 RIV US eng J - Journal Article
Malijevský, Alexandr
Filling, depinning, unbinding: Three adsorption regimes for nanocorrugated substrates.
Physical Review E. Roč. 102, č. 1 (2020), č. článku 012804. ISSN 2470-0045. E-ISSN 2470-0053
R&D Projects: GA ČR(CZ) GA20-14547S
EU Projects: European Commission(XE) 760907 - VIMPP
Institutional support: RVO:67985858
Keywords : capillary condensation * phase-equilibria * interface
OECD category: Physical chemistry
Impact factor: 2.529, year: 2020
Method of publishing: Open access

We study adsorption at periodically corrugated substrates formed by scoring rectangular grooves into a planar solid wall which interacts with the fluid via long-range (dispersion) forces. The grooves are assumed to be macroscopically long but their depth, width, and separations can all be molecularly small. We show that the entire adsorption process can be divided into three parts consisting of filling the grooves by a capillary liquid, depinning of the liquid-gas interface from the wall edges and unbinding of the interface from the top of the wall, which is accompanied by a rapid but continuous flattening of its shape. Using a nonlocal density functional theory and mesoscopic interfacial models all the regimes are discussed in some detail to reveal the complexity of the entire process and subtle aspects that affect its behavior. In particular, it is shown that the nature of the depinning phenomenon is governed by the width of the wall pillars (separating grooves), while the width of the grooves only controls the location of the depinning first-order transition, if present.
Permanent Link: http://hdl.handle.net/11104/0310480