A versatile microfluidic electrochemical platform for diffusion-controlled, quasi-one-dimensional interfacial studies

Area of Science:

• Electrochemistry
• Microfluidics
• Materials Science

Background:

• Dynamic electrochemical processes depend on ion transport and interfacial kinetics.
• Existing experimental setups struggle to achieve diffusion-dominated conditions and visualize evolving interfaces simultaneously.
• Understanding these coupled phenomena is crucial for advancing electrochemical systems.

Purpose of the Study:

• To present a quasi-one-dimensional microfluidic electrochemical platform.
• To suppress convection and eliminate electric field singularities for controlled experiments.
• To enable direct visualization and quantitative analysis of electrochemical interfaces.

Main Methods:

• Fabrication of a microfluidic device with thin-film electrodes and a dielectric overhang.
• Utilizing electrostatic simulations to optimize electrode and overhang geometry.
• Employing in situ optical imaging and difference image analysis for copper electrodeposition.
• Validating mass conservation under diffusion-dominated conditions.

Main Results:

• The dielectric overhang effectively shields the electrode surface and minimizes electric field variations.
• Simulations identified an optimal overhang length for mechanical stability and field control.
• In situ imaging successfully tracked copper electrodeposition morphology and front motion.
• Experimental results confirmed mass balance consistent with quasi-one-dimensional transport.

Conclusions:

• The developed platform provides a versatile tool for investigating electrochemical transport and interfacial phenomena.
• This modular architecture supports various material combinations and advanced imaging techniques.
• The system facilitates systematic studies under diffusion-dominated conditions, advancing electrochemical research.