From theory to simulation: Open interactive MATHCAD simulation protocols for exploring common electrode mechanisms in cyclic voltammetry

Abstract

Cyclic voltammetry is considered as one of the most important techniques in electrochemistry, widely applied to investigate mainly mechanistic aspects, but also kinetics and thermodynamics of various redox processes. Many biochemical transformations in living systems involve electron transfer steps coupled with preceding, follow-up or regenerative chemical reactions, commonly assigned in electrochemistry as CE, EC, and EC′ mechanisms, respectively. Accurately simulating such processes is essential for understanding their behavior and for interpreting experimental voltammetric data. Despite extensive theoretical works available in the literature, freely accessible computational tools for simulating these mechanisms are scarce, thus limiting their use in both teaching and research contexts. This work introduces a set of ready-to-use simulation files developed in software package MATHCAD, designed to model cyclic staircase voltammograms for diffusional CE, EC, and EC′ mechanisms under the Butler-Volmer kinetic formalism. The protocols provided define and explain all relevant physical constants, potential waveform parameters, and dimensionless kinetic and thermodynamic variables required to define recurrent formulas for currents calculation. The approach also highlights the diagnostic value of analyzing relevant features of cyclic voltammograms to recognize particular mechanism from simulated voltammetric patterns. By making these simulation files freely available, the platform offers students and all electrochemists an interactive and intuitive learning tool, while providing experienced scientists with a useful theoretical platform for their experiments. This mainly educational work brings theoretical electrochemistry closer to all electrochemists, while enabling better mechanistic understanding of some of the most important electrode processes.