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Updated: Jun 9, 2026

Fine-tuning the Size and Minimizing the Noise of Solid-state Nanopores
Published on: October 31, 2013
Competitive entry of sodium and potassium into nanoscale pores
James J Cannon1, Dai Tang, Nahmkeon Hur
1Department of Mechanical Engineering, Sogang University, 1 Shinsu-dong, Mapo-gu, Seoul, 121-742, Republic of Korea.
Abstract:
We have studied the competitive entry of potassium and sodium into carbon nanotubes using molecular dynamics simulations. Our results demonstrate how a combination of strong sodium hydration coupled with strong potassium-chlorine interaction leads to enhanced potassium selectivity at certain diameters. We detail the reasons behind this, and show how variation of nanotube diameter can cause a switch to sodium selectivity, or even cause a decrease in overall ion entry despite an increase in diameter. These results demonstrate the importance of considering inter-ion dependence in the theoretical study of pore selectivity and show that, with careful design, the practical separation of sodium and potassium is possible using diameter variation alone.
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