What is the concentration level of the critical species in the solution used in cyclic voltammetry?

In cyclic voltammetry, the ideal concentration of the critical species in the solution is typically very dilute, often at the micro molar level. This is because cyclic voltammetry measures the current response of electroactive species under controlled potential conditions. If the concentration is too high, the voltammetric response can become complicated due to mass transport limitations and overlapping current responses from multiple reactions.

Using a very dilute solution allows for clearer measurements of distinct redox peaks without significant interference from concentration polarization or multiple species’ interactions. The resultant voltammogram in this scenario is easier to interpret, enabling accurate assessment of the electrochemical behavior and kinetics of the species in question.

Additionally, at micro molar concentrations, experiments can minimize the effect of side reactions, thus allowing for a focus on the primary redox processes associated with the critical species being studied. Therefore, the choice of a very dilute solution is essential for obtaining reliable and interpretable results in cyclic voltammetry studies.