Journal of Siberian Federal University. Mathematics & Physics / Modelling the Ionic Conductivity of Nanopores with Electrically Conductive Surface

Full text (.pdf)
Issue
Journal of Siberian Federal University. Mathematics & Physics. 2021 14 (1)
Authors
Krom, Artur I.; Medvedeva, Maria I.; Ryzhkov, Ilya I.
Contact information
Krom, Artur I.: Institute of Computational Modelling of SB RAS Krasnoyarsk, Russian Federation; ; Medvedeva, Maria I.: Siberian Federal University Krasnoyarsk, Russian Federation; ; Ryzhkov, Ilya I.: Institute of Computational Modelling of SB RAS Krasnoyarsk, Russian Federation; Siberian Federal University Krasnoyarsk, Russian Federation;
Keywords
nanopore; ionic conductivity; Space charge model; Uniform potential model
Abstract

The ionic conductivity of nanopores with electrically conductive surface is investigated theoretically. The generalization of two-dimensional (2D) Space–charge model to calculating the ion transport under the applied potential gradient in a nanopore with constant surface potential is proposed for the first time. The results are compared with one-dimensional (1D) Uniform potential model, which is derived from the Space–charge model by assuming the independence of potential, ion concentrations, and pressure on the radial coordinate. We have found that the increase of surface potential magnitude leads to the enhancement of conductivity due to the increase of counter–ion concentration inside the nanopore. It is shown that the 1D and 2D models provide close results when the pore radius is smaller than the Debye length. Otherwise, the 1D model essentially overestimates the ionic conductivity. According to the 2D model, the ionic conductivity decreases with increasing the nanopore radius, while the 1D model predicts the opposite trend, which is not physically correct

Pages
74–86
DOI
10.17516/1997-1397-2021-14-1-74-86
Paper at repository of SibFU
https://elib.sfu-kras.ru/handle/2311/137820