In short, an electronic device that measures and controls the potential (or voltage) difference between two electrodes is called a potentiostat. The advantage of a potentiostat is that it has complete control over the applied potential, unlike other power sources, while measuring the response current. Potentiostats are mainly used in electrochemistry, although other fields make use of them as well.
A potentiostat applies potential to a certain surface, an electrode. The amount of electrons on the surface is thereby reduced or increased. This causes the liquid to be triggered to deliver or consume electrodes to compensate for this. The exchange of electrons per time, the electrode’s current, can be measured by the potentiostat. This is usually done in a three-electrode setup (Figure 1).
For more information, see Chapter Potentiostats.
In this section the reasons for the three electrode setup of most potentiostats is explained, what the task of each electrode is and what to take into consideration when choosing your counter electrode.
Here are some general comments on trouble shooting that are valid for any experiment. We made this list to enable even not very experienced users to find the sources of trouble as soon as possible to keep the frustration level for you and coworkers as low as possible.