Kinetics and Mass Transfer Limitations of the Electrode Reaction

Kinetics and Mass Transfer Limitations of the Electrode Reaction 

The overpotential terms of Equations (17.5) and (17.6) are the driving forces of the electrochemical reaction. The most commonly used kinetic expression in electrochemistry is undoubtedly the Tafel law, which predicts an exponential increase of the current density of the desired reaction, Ia, with the electrode overpotential. For the anodic reaction of Equation (17.1)  

Under steady-state conditions, the reagent flux from the bulk to the electrode surface, frequenfly modeled by a Newton-type law, equals the reagent consumption due to the electrochemical reaction  

For high anodic overpotentials, a limiting current density, corresponding to the maximum possible mass transfer, is obtained  

Due to economic factors, large-scale processes are generally driven close to the transport-limited rate [2]. 

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