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Updated: Feb 15, 2026
08:06
Merging Ion Concentration Polarization between Juxtaposed Ion Exchange Membranes to Block the Propagation of the Polarization Zone
Published on: February 23, 2017
9.0K
Confined Electroconvective Vortices at Structured Ion Exchange Membranes
Joeri de Valença1,2, Morten Jõgi2, R Martijn Wagterveld2
1Soft Matter, Fluidics and Interfaces Group, MESA+ Institute of Nanotechnology, University of Twente , 7500AE Enschede, The Netherlands.
Langmuir : the ACS Journal of Surfaces and Colloids
|January 19, 2018
Summary
Investigating ion transport in cation exchange membranes, this study shows that structured membrane geometry significantly impacts electroconvection. Tailored structures reduce resistance by 50% and confine microvortices for efficient ion migration.
Area of Science:
- Electrochemistry
- Fluid Dynamics
- Materials Science
Background:
- Concentration polarization can induce electroconvective microvortices at cation exchange membranes.
- Membrane geometry plays a crucial role in electrokinetic phenomena.
Purpose of the Study:
- To investigate electroconvective ion transport at cation exchange membranes with varying square-wave structures.
- To understand the effect of membrane topology on electroconvection and ion transport dynamics.
Main Methods:
- Experimental investigation of ion transport using electrical, flow, and concentration measurements.
- Numerical simulations employing Poisson-Nernst-Planck and Navier-Stokes equations.
Main Results:
- Applied potential for electroconvection is strongly influenced by membrane geometry.
- A 50% resistance reduction was observed when structure size matched the mixing layer (ML) thickness.
- Confined vortices with reduced lateral motion were achieved with structured membranes compared to flat ones.
Conclusions:
- Membrane topology significantly affects electrokinetic and electrohydrodynamic behavior.
- Advection and migration dominate in the vortex ML, while diffusion and migration are key in the stagnant diffusion layer.
- Structured membranes offer enhanced control over ion transport.
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