I thought absolute electrode potential is Galvani potential difference at the interface. However, it is given by following equation in John Bockris - Modern Electrochemistry (Ref.1): $$ E^M \mathrm{(abs)} = \Delta^M_S\phi - \frac{\mu_e^M}{F} $$

First term is Galvani potential difference on the metal/solution interface and the other is chemical potential of electrons in the metal divided by Farady's constant.

Question 1: Why is chemical potential of electrons in metal included in the definition?

On the other hand, on Wikipedia, absolute electrode potential is defined as: $$E^M \mathrm{(abs)} = \Delta^M_S\psi + \phi^M $$

Where second term is work function of the metal. This definiton is a little bit different than in Ref.1 since work function includes surface potential difference on the interface in addition to chemical potential of electrons in the metal.

Question 2: Why are these two definitions different?


  1. John O’M. Bockris and Amulya K. N. Reddy, In Modern Electrochemistry: An Introduction to an Interdisciplinary Area, Volume 2; Plenum Press: New York, NY, 1970 (ISBN: 978-1-4615-8600-5).
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    $\begingroup$ Please look at the equations I edited are the one you meant to say. Also, see the reference 1 whether it is the correct edition you got the equation. $\endgroup$ Jul 22, 2021 at 13:58
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    $\begingroup$ Oh, yes. I didn't add references on reference list. Thank you. Your edits of equations are correct, I just used notation which came to me since I think it is not too important. $\endgroup$ Jul 22, 2021 at 15:17


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