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Updated: Aug 6, 2026
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Fine-tuning the Size and Minimizing the Noise of Solid-state Nanopores
Published on: October 31, 2013
Length-Dependent Inversion of Ion Current Rectification in Conical Nanopores
Qiang Chen1, Zhongjie Jia1, Yahui Xue1
1Department of Mechanics and Aerospace Engineering & Center for Complex Flows and Soft Matter Research, Southern University of Science and Technology (SUSTech), Shenzhen518055, P. R. China.
Langmuir : the ACS Journal of Surfaces and Colloids
|July 20, 2026
Summary
Nanopore length controls ion current rectification (ICR) direction in conical nanopores. Increasing length reverses ion flow from base-to-tip to tip-to-base, enabling tunable nanofluidic diode behavior.
Area of Science:
- Nanotechnology
- Physical Chemistry
- Electrokinetics
Background:
- Ion current rectification (ICR) in conical nanopores is crucial for energy harvesting, sensing, and computing.
- The impact of nanopore length on ICR is not well understood.
Purpose of the Study:
- To investigate the influence of nanopore length on ion current rectification in conical nanopores.
- To understand the mechanism behind length-dependent ICR inversion.
Main Methods:
- Utilized size-modified Poisson-Nernst-Planck (SMPNP) simulations.
- Incorporated finite-size effects into the simulations.
Main Results:
- Demonstrated a length-dependent inversion of ICR in conical nanopores.
- Observed a reversal of preferential ion transport direction with increasing pore length.
- Identified electric potential drop localization at the tip as the mechanism for inversion.
Conclusions:
- Nanopore length is a critical design parameter for nanofluidic diodes.
- Rectification direction can be engineered by tuning nanopore length and other parameters.
- Provides a predictive framework for designing nanofluidic devices.
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