Ionic contribution to the electric current in an electrolytic cell submitted to an external voltage

Area of Science:

• Electrochemistry
• Physical Chemistry
• Materials Science

Background:

• Electrical current in electrolytic cells is influenced by ion movement.
• External electric fields can induce ion separation and affect charge density.
• Understanding ion dynamics is crucial for optimizing electrochemical devices.

Purpose of the Study:

• To evaluate the ionic contribution to electrical current in an electrolytic cell under a time-dependent voltage.
• To analyze ion behavior in both low and high electric field regimes.
• To determine how ion density and mobility can be extracted from current measurements.

Main Methods:

• Theoretical analysis of ionic current under a linearly increasing external voltage.
• Modeling ion separation using a surface charge density approach.
• Investigating the system's response in the limits of small and large electric fields.

Main Results:

• A characteristic peak in electrical current was observed, followed by a delay relative to voltage application.
• The ion density's dependence on the electric field was considered.
• The study demonstrates that ion behavior directly influences the observed current profile.

Conclusions:

• The current peak and delay phenomenon are direct consequences of ionic contributions.
• Analysis of these features allows for the determination of equilibrium ion density.
• The mobility of ions within the liquid can be accurately estimated from the peak and delay characteristics.