Determination of electrochemical reaction orders from Tafel lines

1 Determination of electrochemical reaction orders from Tafel lines 

The Tafel lines derived from this equation are 

Measurement of the Tafel lines for different concentrations, the partial electrochemical reaction orders, can be detennined from Eqs. (6.34) and (6.35). This implies that the concentration at the electrode surface remains approximately equal to the bulk concentration (elimination of the diffusion overpotential). It should be pointed out that for this evaluation the logarithm of current must be plotted versus the electrode potential and not versus the overpotential. 

The charge transfer coefficients determined from the slope of the Tafel lines were = 0.66 and = 1 — = 0.36. 

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