Diffusion Limited Current (i_lim)

A few hundred millivolts or so after a feature in a CV, the current decreases after hitting the peak and converges to a constant current, known as the mass transport or diffusion limited current. As the name suggests, at this point in the scan, the potential is so far past the E_1/2 and electron transfer is so favorable that electrons transfer to analyte molecules as soon as they approach the electrode. This means that the rate of electron transfer (current) depends solely on the rate at which analyte can diffuse to or from the electrode. The diffusion limited current can be used to find the diffusion coefficient of the analyte.

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