Ions redistribution and meniscus relaxation during Langmuir wetting process
journal contribution
posted on 2011-05-26, 11:17authored byV.I. Kovalchuk, M.P. Bondarenko, E.K. Zholkovskiy, Victor Starov, D. Vollhardt
Nonstationary kinetics of the ion redistribution
within the meniscus region during deposition of a charged
Langmuir monolayer after beginning or stopping of the substrate
motion is analyzed on the basis of the results of numerical
simulations. The time evolution of the ions concentration
profiles forming at the contact line and propagating toward the
bulk solution is considered. It is shown that the diffusion front
propagates much slower within the region of overlapping diffuse
layers than outside of this region. At the beginning of the
deposition process a region characterized by quasi-stationary
behavior of the ion concentration and electric potential distributions
is formed in close vicinity to the contact line. A stationary
deposition regime is established when the region of quasi-stationary distributions reaches the external boundary of the Nernst layer
provided that the substrate motion is not very fast. For the substrate velocities higher than the critical one the concentration near the
contact line can decrease to such small values which do not allow a stable deposition process. The developed mathematical model
allows addressing to transient regimes of the monolayer deposition which are very important for understanding the mechanisms
leading to meniscus instability.
History
School
Aeronautical, Automotive, Chemical and Materials Engineering
Department
Chemical Engineering
Citation
KOVALCHUK, V.I. ... et al, 2011. Ions redistribution and meniscus relaxation during Langmuir wetting process. The Journal of Physical Chemisty B, 115 (9), pp.1999–2005.