Modeling of Ion Diffusion Induced Current through a Nanochannel

Ming-Chun Chien (1) , F.-C. Yang (2) , G.-J. Wang (1)

1 Dep. of Mechanical Engineering
2 Institute of Industrial Engineering

In this article, a theoretical model that takes into consideration both the diffusion and electric osmosis fluxes to estimate the diffusion current through a nanochannel is proposed. Equivalent impedance of a nanochannel is modeled as a series connection of finite RC circuits. The impedances of the electrical double layer and buffer solution in each infinitesimal RC circuit are represented by a capacitor and a resister, respectively. Due to the electrical double layer effect, the diffusion induced current in the proposed model is position dependent. Computer simulations and experiments using a nanoporous anodic aluminum oxide (AAO) thin film as the filter to separate electrolysis with ion concentration gradient are conducted. A high degree coincidence between the theoretical and experimental data is observed.

Mots clés: Ion diffusion induced current; Nanochannel; Concentration gradient

Domaines: Science des matériaux [cond-mat.mtrl-sci]

Ming-Chun Chien, F.-C. Yang, G.-J. Wang. Modeling of Ion Diffusion Induced Current through a Nanochannel. ENS 2006, Dec 2006, Paris, France. pp.134-138. ⟨hal-00166778⟩