Electrokinetic behavior of a pH-regulated dielectric cylindrical nanopore
Journal
Journal of Colloid and Interface Science
Journal Volume
588
Pages
94-100
Date Issued
2021
Author(s)
Abstract
A continuum model is adopted to describe the electrokinetic behavior of a pH-regulated cylindrical nanopore, the surface of which has charge-regulated carboxyl groups. We focus on the influences of the permittivity of the nanopore material, nanopore size, salt concentration, and solution pH on this behavior, and the underlying mechanisms. The influence of the nanopore permittivity becomes significant when a nanopore is shorter than ca. 50 nm. It is interesting to observe that if it is longer than ca. 100 nm, the nanopore conductance decreases with increasing permittivity. If it is sufficiently short, the conductance increases with increasing permittivity. If the nanopore length takes a medium level, the conductance is insensitive to the variation in the permittivity. For a short nanopore (~20 nm), the conductivity increases with increasing permittivity. However, if pH is sufficiently high, it becomes insensitive to permittivity. Although the larger the permittivity the greater the conductivity, in general, this effect becomes insignificant when the bulk salt concentration is sufficiently high, implying that the effect of membrane polarization is important only if the bulk salt concentration is sufficiently low. ? 2020 Elsevier Inc.
Subjects
Continuum mechanics; Electrodynamics; Permittivity; Carboxyl groups; Continuum Modeling; Cylindrical nanopores; Electro-kinetic; Membrane polarization; Nanopore size; Salt concentration; Solution pH; Nanopores; aluminum oxide; nanochannel; polymer; protein; silicon derivative; sodium chloride; aqueous solution; Article; conductance; diffusion coefficient; electric potential; electroosmotic flow; equilibrium constant; ion transport; membrane polarization and depolarization; pH; priority journal; simulation; viscosity
SDGs
Type
journal article