Rotating Disk Electrode and Limiting Current

Benjamin (Veniamin) Levich (1917-1987) was a Ukraine-bom American physical chemist who contributed to the development of the fundamental theory describing the RDE. The famous Levich equation describes the current at an RDE, which is one of the key techniques in electrochemical kinetics. 

Inzelt, and F. Scholz, Electrochemical Dictionary, Springer, Berhn, Germany, 2008. 

The convective-diffusion Equation 7.8 in the case of two-dimensional system in a steady state [(dddt) = 0] in cylindrical coordinates is as follows  

The RDE allows defining the Nemst diffusion layer thickness, 8n, which depends on (1) the diffusion coefficient of the electrochemically active species, (2) kinematic viscosity of the solution, and (3) rotation rate of the electrode as follows  

the limiting current density on the RDE can theoretically be calculated if the bulk concentration of the electrochemically active species of the reactant is known  

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