The limiting current, in electrochemistry, is the limiting value of a faradaic current

Faradaic current

The faradaic current is the current generated by the reduction or oxidation of some chemical substance at an electrode. The net faradaic current is the algebraic sum of all the faradaic currents flowing through an indicator electrode or working electrode....

 that is approached as the rate of charge-transfer

Charge-transfer

Charge-transfer may refer to:* Intervalence charge transfer* Charge-transfer complex* Charge-exchange ionization, a form of gas phase ionization...

 to an electrode

Electrode

An electrode is an electrical conductor used to make contact with a nonmetallic part of a circuit...

 is increased . The limiting current can be approached, for example, by increasing the electric potential

Electric potential

In classical electromagnetism, the electric potential at a point within a defined space is equal to the electric potential energy at that location divided by the charge there...

 or decreasing the rate of mass transfer

Mass transfer

Mass transfer is the net movement of mass from one location, usually meaning a stream, phase, fraction or component, to another. Mass transfer occurs in many processes, such as absorption, evaporation, adsorption, drying, precipitation, membrane filtration, and distillation. Mass transfer is used...

 to the electrode. It is independent of the applied potential over a finite range, and is usually evaluated by subtracting the appropriate residual current from the measured total current. A limiting current can have the character of an adsorption

Adsorption

Adsorption is the adhesion of atoms, ions, biomolecules or molecules of gas, liquid, or dissolved solids to a surface. This process creates a film of the adsorbate on the surface of the adsorbent. It differs from absorption, in which a fluid permeates or is dissolved by a liquid or solid...

, catalytic, diffusion

Diffusion

Molecular diffusion, often called simply diffusion, is the thermal motion of all particles at temperatures above absolute zero. The rate of this movement is a function of temperature, viscosity of the fluid and the size of the particles...

, or kinetic current, and may include a migration current.