Elimination of diffusion contribution to the overpotential in chronoamperometry and chronopotentiometry

2 Elimination of diffusion contribution to the overpotential in chronoamperometry and chronopotentiometry 

In chronoamperometry, after switching on an overpotential, the time dependence of the current is monitored. For purely diffusion-controlled processes, the current depends on time according to the Cottrell equation in Chapter 5, Eq. (5.20). The current decreases proportional to 1/Vt. The combination with charge transfer control leads to the following 

Switching to potentials in the cathodic Tafel region one obtains 

An example was the determination of charge transfer controlled current densities in the HNO2-HNO3 redox system (Section 6.2.1). 

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