DoITPoMS - TLP Library Batteries - Tafel curve of copper electrode

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Tafel curve of copper electrode

The half-cell reaction for copper is:

Cu²⁺ + 2e^- → Cu ; E^o = +0.34V

The exchange current density is i_o = 1 A m^-2

For the Tafel equation:

The Tafel slope is given by:

Taking:
T = 300 K
α = 0.5
Z = 2

We get:
b_A = 0.059 V/decade of current
and
b_C = -0.059 V/decade of current

For the anodic curve: η_A = E_A – E^o
E_A = E^o + η_A

For the cathodic curve: η_C= E_C – E^oE_C = E^o + η_C

The plot of this is shown on the diagram below: