What happens in step 3 of the cyclic voltammetry process?

In step 3 of the cyclic voltammetry process, the sweep reverses once the upper limit is reached. This reversal is a key characteristic of cyclic voltammetry, which involves a triangular wave-like potential sweep where the potential is ramped in one direction to a predetermined upper limit and then reversed back to the starting point.

During this reversal, the electrochemical reactions that occurred in the forward sweep (where oxidation or reduction takes place) are typically reversed. As a result, capturing the resulting current provides valuable information about the electrochemical processes, including reaction kinetics, reversibility, and diffusion properties.

The other options reflect different phenomena that do not occur at this specific step in cyclic voltammetry. For instance, the current stabilizing at a fixed value suggests a steady state not characteristic of this dynamic process. Similarly, the notion that the voltage remains unchanged conflicts with the fundamental characteristic of cyclic voltammetry, where the voltage is actively being swept. The idea that the current continues to increase indefinitely is also inaccurate, as current levels typically oscillate based on the electrochemical reactions taking place at the electrode. Hence, the reversal of the sweep at the upper limit is what defines this step in the cyclic voltammetry process and marks the transition to the