Cyclic voltammetry with non-triangular waveforms: Electrochemically reversible systems

Abstract

Cyclic voltammetry is typically performed using triangular waveforms, however, complications inevitably arise from the discontinuous nature of the differentiated triangular wave: As the capacitive current contributions are proportional to the derivative of the applied electrode potential, the measured current is (at least theoretically) discontinuous, which experimentally manifests in perturbed voltammetric data following minima and maxima in the applied triangular wave that is mostly due to unavoidable parasitic capacitances. We herein investigate voltammetry using alternative waveforms which on the one hand circumvent such difficulties and on the other exhibit unique features in the voltammetric response. We show that these features immediately reveal the formal potential of an investigated reaction that is readily available without any need for further data processing, and enable a new and easy-to-use route to determine formal potentials.