Chronoamperometry

The functional relationship between current response and time is measured after applying single or double potential step to the working electrode of the electrochemical system.

However, as with all pulsed techniques, chronoamperometry generates high charging currents, which decay exponentially with time as any RC circuit.

In most electrochemical cells, this decay is much slower than the charging decay-cells with no supporting electrolyte are notable exceptions.

Since the current is integrated over relatively longer time intervals, chronoamperometry gives a better signal-to-noise ratio in comparison to other amperometric techniques.

[4] Anthracene in deoxygenated dimethylformamide (DMF) will be reduced (An + e− -> An−) at the electrode surface that is at a certain negative potential.

In 1902, F. G. Cottrell deduced the linear diffusion on a planar electrode according to the diffusion law and Laplace transform, and obtained the Cottrell equation: where Under controlled-diffusion circumstances, the current-time plot reflects the concentration gradient of the solution near the electrode surface.

During this process, a constant potential is applied to the working electrode and current is monitored over time.

Total charge (n value) is calculated by integration of area under the current plot and the application of the Faraday's law.

The cell for controlled-potential (bulk) electrolysis is usually a two-compartment (divided) cell, contained a carbon rod auxiliary anode and is separated from the cathode compartment by a coarse glass frit and methyl cellulose solvent electrolyte plug.

The working electrode for bulk electrolysis could be a RVC disk, which has larger surface area to increase the rate of the reaction.

Under this period, the default condition involves holding the working electrode potential of initial state for another approximate 1 seconds.

The chronopotentiometry experiment could be done in a very short time period, so it is a good method to study the adsorption behavior at the electrode surface.

Chronocoulometry has the following differences with chronoamperometry: the signal increases over time instead of decreasing; the act of integration minimizes noise, resulting in a smooth hyperbolic response curve; and contributions from double-layer charging and absorbed species are easily observed.