Reversible voltammetry at cylindrical electrodes: Validity of a one-dimensional model

The cyclic voltammetry of a reversible one-electron-transfer electrochemical reaction is investigated using finite difference simulations at three electrode geometries: an ‘infinitely long cylinder’ electrode featuring a cylindrical electrode with an infinite length, an ‘annular band’ electrode, whose band-shape electrochemically active area is located around an infinitely long insulating cylinder, and a ‘full cylinder’ electrode which resembles the microwire electrodes widely used in electrochemical experiments with both side and end active. Following the simulation of the infinitely long cylindrical electrode, a polynomial equation is introduced to describe the forward peak potentials at different scan rates. Based on further simulations of the other two electrodes, we find if the lengths of the latter are greater than ~ 104 times the radius of the cylinders, the electrochemical reversible cyclic voltammetry of them can be well described by the infinitely long cylinder model with errors of less than 1%