10.1021/la902355x.s001
Anthony Szymczyk
Anthony
Szymczyk
Haochen Zhu
Haochen
Zhu
Béatrice Balannec
Béatrice
Balannec
Pressure-Driven Ionic Transport through Nanochannels with Inhomogenous Charge Distributions
American Chemical Society
2010
charge distributions
pressure difference
Debye screening length
salt rejection rate exhibits
nanopore
ion rejection capabilities
charge concentration
salt rejection rate
nonmonotonous variation
Inhomogenous Charge DistributionsThe effect
volume charge density
unipolar charge distributions
charge distribution
2010-01-19 00:00:00
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Pressure_Driven_Ionic_Transport_through_Nanochannels_with_Inhomogenous_Charge_Distributions/2798641
The effect of spatially inhomogeneous fixed charge distributions on the pressure-driven transport of ions through cylindrical nanopores have been investigated theoretically by means of an approximate version of the Poisson−Nernst−Planck model that can be used with confidence for moderately charged nanopores with radius smaller than the Debye screening length of the system. Salt rejection rate has been computed as a function of the applied pressure difference for various one-dimensional (1D) unipolar charge distributions and has been compared with that obtained for a homogeneously charged nanochannel with an identical average volume charge density. The ion rejection capabilities of charged nanopores can be optimized by an appropriate distribution of the fixed charge concentration. When ions are forced to enter the nanopores by the end with the lowest fixed charged concentration, the salt rejection rate exhibits a nonmonotonous variation with the applied pressure. This phenomenon has been attributed to the influence of the inhomogeneous charge distribution on the electric field that arises spontaneously so as to maintain the electroneutrality within the nanopore.