Wetting in hydrophobic nanochannels: a challenge of classical capillarity.
We report an investigation of the water-hydrophobic interface in well-defined nanochannels (R approximately 2-4 nm). Wetting in these systems cannot be described by classical (macroscopic) capillary theory: (1) water occupies only a fraction ( approximately 60%) of the pore volume, and (2) the capillary pressures are approximately 60-90% greater than predicted by the Laplace equation. The results suggest the presence of approximately 0.6 nm layer of low-density fluid (vapor) separating water from the hydrophobic solid.
Helmy
Roy
R
Department of Chemistry and Biochemistry, Seton Hall University, South Orange, New Jersey 07079, USA.
Kazakevich
Yuri
Y
Ni
Chaoying
C
Fadeev
Alexander Y
AY
D002196:Capillaries; D002197:Capillary Action; D043942:Nanotubes / Q000737:chemistry*; D010316:Particle Size; D016062:Porosity; D012822:Silicon Dioxide / Q000737:chemistry*; D013499:Surface Properties; D014867:Water / Q000737:chemistry; D017155:Wettability
D014867:Water; D012822:Silicon Dioxide