Electrochemistry at Ultramicroelectrodes—Simulation of Heterogeneous and Homogeneous Kinetics by an Improved ADI—Technique

Electrochemistry at Ultramicroelectrodes has become a promising method for measurement and evaluating of electrode kinetics. However, its theoretical treatment is a challenging problem on account of the unusual diffusive mass transport connected with such small electroactive areas. To simplify the computation and to open the way for the use of personal computers an improved alternating direction implicit (ADI) technique based on an implicit Crank‐Nicolson scheme has been developed. The numerical approach allows modelling of all types of electrode reactions including coupled homogeneous processes at ultramicroelectrodes. Numerical results for the reversible and the quasireversible charge transfer as well as first‐ and second‐order follow‐up reactions are presented.