Kinetic constants electrodes, Koutecky-Levich

The rate constant, k, may then be derived from variation of the plateau current with the rotation rate by means of the popular Koutecky-Levich plots, where the inverse of the plateau current is plotted against the inverse of the square root of the rotation rate (Figure 4.12). The intercept allows the determination of the kinetic constant kr°, and of the rate constant k, if the amount of catalyst on the electrode surface is known. 

In zone R, all three phenomena that take place in the film are fast compared to the diffusion of the substrate from the bulk of the solution to the film-solution interface. The concentrations of both Q and A are constant through the film. The RDEV response is similar to that of a monolayer coating (Section 4.3.2), except that more catalytic material is present on the surface of the electrode (it is multiplied by the number of layers in the multilayered coating). A linear Koutecky-Levich plot is obtained from the intercept, from which the kinetics of the catalytic reaction can be characterized. 

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