Sampled DC Voltammetry Purpose

Sampled DC Voltammetry (SDC) is used for both quantitative chemical analysis and to study the mechanism, kinetics, and thermodynamics of chemical reactions.

SDC is the digital version of the most venerable polarographic/voltammetric technique from the early days of electrochemistry, in which an analog voltage “ramp” was applied to the working electrode. If the electrode was a solid electrode (Pt, Au, glassy carbon), the technique is generally referred to as Linear Sweep Voltammetry. If the electrode was a Dropping Mercury Electrode, the technique was called Polarography and was characterized by large current fluctuations as a result of the change in size of the mercury drop as it grew and fell.

In Sampled DC Voltammetry, the voltage is applied to the working electrode as a staircase waveform. The current is sampled electronically immediately prior to each step. This method of current measurement results in a smooth S-shaped voltammogram with a DME. In terms of sensitivity, SDC is the least sensitive technique in the Pulse Voltammetry software. SDC may be performed on a stationary solid electrode, a rotated electrode, a hanging mercury drop electrode, a Static Mercury Drop Electrode, or a dropping mercury electrode. The SDC script in the Pulse Voltammetry provides for mercury-drop generation, solution de-aeration, and experiment-sequencing suitable for the most common applications for Sampled DC Voltammetry. Choose the type of electrode using the Electrode Setup Panel. Additional sequencing steps suitable for sampled DC anodic (or cathodic) stripping are implemented in the software’s SDCS (Sampled DC Stripping) technique.