Microfluidics and Nanofluidics

, Volume 8, Issue 5, pp 703–708 | Cite as

Structure and charging kinetics of electrical double layers at large electrode voltages

  • Clint Cagle
  • Guang Feng
  • Rui Qiao
  • Jingsong Huang
  • Bobby G. Sumpter
  • Vincent Meunier
Short Communication

Abstract

The structure and charging kinetics of electrical double layers (EDLs) at interfaces of NaCl solutions and planar electrodes are studied by molecular dynamics (MD) and Poisson–Nernst–Planck (PNP) simulations. Based on the MD results and prior experimental data, we show that counterion packing in planar EDLs does not reach the steric limit at electrode voltages below 1 V. In addition, we demonstrate that a PNP model, when complemented with a Stern model, can be effectively used to capture the overall charging kinetics. However, the PNP/Stern model can only give a qualitative description of the fine features of the EDL.

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Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  • Clint Cagle
    • 1
  • Guang Feng
    • 1
  • Rui Qiao
    • 1
  • Jingsong Huang
    • 2
  • Bobby G. Sumpter
    • 2
  • Vincent Meunier
    • 2
  1. 1.College of Engineering and ScienceClemson UniversityClemsonUSA
  2. 2.Oak Ridge National LaboratoryOak RidgeUSA

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