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Title: Surface Charge Density Determination of Single Conical Nanopores Based on Normalized Ion Current Rectification

Abstract

Current rectification is well-known in ion transport through nanoscale pores and channel devices. The measured current is affected by both the geometry and fixed interfacial charges of the nanodevices. In this paper, an interesting trend is observed in steady-state current-potential measurements using single conical nanopores. A threshold low conductivity state is observed upon the dilution of electrolyte concentration. Correspondingly, the normalized current at positive bias potentials drastically increases and contributes to different degree of rectification. The novel opposite trend at opposite bias polarities is employed to differentiate the ion flux affected by the fixed charges at the substrate-solution interface (surface effect), with respect to the constant asymmetric geometry (volume effect). The surface charge density (SCD) of individual nanopores, an important physical parameter that is challenging to measure experimentally and is known to vary from one nanopore to another, are directly quantified by solving Poisson and Nernst-Planck equations in the simulation of the experimental results. Flux distribution inside the nanopore and SCD of individual nanopores are reported. The respective diffusion and migration translocations are found to vary at different positions inside the nanopore. The knowledge is believed important for resistive pulse sensing applications, as the detection signal is determined by themore » perturbation of ion current by the analytes.« less

Authors:
 [1];  [1];  [1];  [1];  [1];  [1];  [1]
  1. Georgia State Univ., Atlanta, GA (United States). Dept. of Chemistry
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1033178
DOE Contract Number:  
AC05-00OR22725
Resource Type:
Journal Article
Journal Name:
Langmuir
Additional Journal Information:
Journal Volume: 28; Journal Issue: 2; Journal ID: ISSN 0743-7463
Publisher:
American Chemical Society
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS

Citation Formats

Liu, Juan, Kvetny, Maksim, Feng, Jingyu, Wang, Dengchao, Wu, Baohua, Brown, Warren, and Wang, Gangli. Surface Charge Density Determination of Single Conical Nanopores Based on Normalized Ion Current Rectification. United States: N. p., 2011. Web. doi:10.1021/la203106w.
Liu, Juan, Kvetny, Maksim, Feng, Jingyu, Wang, Dengchao, Wu, Baohua, Brown, Warren, & Wang, Gangli. Surface Charge Density Determination of Single Conical Nanopores Based on Normalized Ion Current Rectification. United States. https://doi.org/10.1021/la203106w
Liu, Juan, Kvetny, Maksim, Feng, Jingyu, Wang, Dengchao, Wu, Baohua, Brown, Warren, and Wang, Gangli. Mon . "Surface Charge Density Determination of Single Conical Nanopores Based on Normalized Ion Current Rectification". United States. https://doi.org/10.1021/la203106w.
@article{osti_1033178,
title = {Surface Charge Density Determination of Single Conical Nanopores Based on Normalized Ion Current Rectification},
author = {Liu, Juan and Kvetny, Maksim and Feng, Jingyu and Wang, Dengchao and Wu, Baohua and Brown, Warren and Wang, Gangli},
abstractNote = {Current rectification is well-known in ion transport through nanoscale pores and channel devices. The measured current is affected by both the geometry and fixed interfacial charges of the nanodevices. In this paper, an interesting trend is observed in steady-state current-potential measurements using single conical nanopores. A threshold low conductivity state is observed upon the dilution of electrolyte concentration. Correspondingly, the normalized current at positive bias potentials drastically increases and contributes to different degree of rectification. The novel opposite trend at opposite bias polarities is employed to differentiate the ion flux affected by the fixed charges at the substrate-solution interface (surface effect), with respect to the constant asymmetric geometry (volume effect). The surface charge density (SCD) of individual nanopores, an important physical parameter that is challenging to measure experimentally and is known to vary from one nanopore to another, are directly quantified by solving Poisson and Nernst-Planck equations in the simulation of the experimental results. Flux distribution inside the nanopore and SCD of individual nanopores are reported. The respective diffusion and migration translocations are found to vary at different positions inside the nanopore. The knowledge is believed important for resistive pulse sensing applications, as the detection signal is determined by the perturbation of ion current by the analytes.},
doi = {10.1021/la203106w},
url = {https://www.osti.gov/biblio/1033178}, journal = {Langmuir},
issn = {0743-7463},
number = 2,
volume = 28,
place = {United States},
year = {2011},
month = {12}
}