How many molecules are required to measure a cyclic voltammogram?

The stochastic limit at which fully-reversible cyclic voltammetry can accurately be measured is investigated. Specifically, Monte Carlo GPU simulation is used to study low concentration cyclic voltammetry at a microdisk electrode over a range of scan rates and concentrations, and the results compared to the statistical limit as predicted by finite difference simulation based on Fick’s Laws of Diffusion. Both Butler–Volmer and Marcus–Hush electrode kinetics are considered, simulated via random-walk methods, and shown to give identical results in the fast kinetic limit.