Water-induced ethanol dewetting transition.
The dewetting transitions of two hydrophobic plates immersed in pure water, aqueous ethanol solutions with concentrations from 25% to 90%, and pure ethanol were investigated by molecular dynamics simulations, where the dewetting transition was analogous to a first-order phase transition from liquid to vapor. It was found that the dewetting transitions occurred except that in the pure ethanol system. Although the ethanol molecules prefer to locate in the vicinity of the two plates, the inter-plate region is unfavorable for water molecules, due to losing more than one hydrogen bond. Moreover, each inter-plate water molecule forms hydrogen bonds on average with about two ethanol molecules. These intermolecular hydrogen bonds cause water and ethanol to cooperatively fill or exit the inter-plate region. Thus, water molecules play a more important role in the inter-plate filling/empty process, and induce the ethanol dewetting transition. Our results provide insight into the effect of water on the ethanol dewetting phenomena.
Shanghai Institute of Applied Physics, Chinese Academy of Sciences, P.O. Box 800-204, Shanghai, 201800, China.
Xiuping
X
Ren
Bo
B
Zhou
Chunlei
C
Wang
D000431:Ethanol / Q000737:chemistry*; D006860:Hydrogen Bonding; D008968:Molecular Conformation; D056004:Molecular Dynamics Simulation; D014867:Water / Q000737:chemistry*; D017155:Wettability
D014867:Water; D000431:Ethanol