Basic principles of an electrochemical simulation

Although a simulator may be taken as a black box, the user will soon find that some basic knowledge of the principles of electrochemical simulations is essential. A simple simulation will now be described to highlight the fundamental principles of electrochemical modelling. For additional information, readers should consult Blitz s excellent book (66) and Speiser s extensive review (67). 

The following assumptions are made (1) the electrode is planar and the reaction is a fast electron transfer (2) only O is present in the cell initially (3) the diffusion coefficients of O and R are identical (4) the potential of the electrode is stepped from a value where no reaction occurs to one where the reaction is diffusion controlled (5) the objective is to predict the current transient and the concentration profiles as a function of time. Under these conditions, the latter should be given by equation (11.2.5) and the former by equation (11.2.7). Using the following definitions  

Using finite difference approximations (66), the discrete form of equation (11.3.6) obtained  

Many different numerical simulations have been reported, often more accurate and more efficient than EFD. Some include two-dimensional mass transport but they are outside the 

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