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Updated: Apr 7, 2026
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AC Electrokinetic Phenomena Generated by Microelectrode Structures
Published on: July 28, 2008
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Electron-electrolyte coupling in AC transport through nanofluidic channels.
Baptiste Coquinot1,2, Mathieu Lizée1, Lydéric Bocquet1
1Laboratoire de Physique de l'École Normale Supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université Paris Cité, 24 rue Lhomond, 75005 Paris, France.
The Journal of Chemical Physics
|April 6, 2026
Summary
This study reveals how alternating current (AC) driving in nanofluidic channels couples ion and electron transport. Electron participation in ionic current defines new conductivity regimes and modifies fluid flow, offering insights into interfacial phenomena.
Area of Science:
- Physical Chemistry
- Nanotechnology
- Surface Science
Background:
- Nanofluidic transport is typically studied under direct current (DC) or pressure. Alternating current (AC) driving offers a dynamic approach to understanding time-dependent transport mechanisms.
- Electrochemical methods inspire investigations into coupled ionic and electronic transport under AC conditions.
Purpose of the Study:
- To investigate the coupling between ionic and electronic transport in nanofluidic channels under AC driving.
- To analyze the impact of electron-ion coupling on electro-osmotic flows and identify distinct AC transport signatures.
Main Methods:
- Theoretical investigation of electron-ion coupling under AC driving in nanofluidic systems.
- Analysis of capacitive electrochemical coupling between channel wall conduction electrons and ionic current.
- Modeling of fluctuation-induced momentum transfer between electrolyte and wall electrons.
Main Results:
- Conduction electrons participate in ionic current via capacitive coupling, establishing a critical frequency and length scale for electron-dominated conductivity.
- Electron-ion coupling modifies electro-osmotic flows.
- Distinct AC transport signatures emerge based on charge carrier polarity due to momentum transfer.
Conclusions:
- A frequency-dependent transport matrix coupling ionic, electronic, and hydrodynamic flows is established.
- AC nanofluidic transport serves as a powerful probe for interfacial phenomena under confinement.
- Findings suggest new avenues for engineering nanofluidic devices via electron-electrolyte coupling.
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