The steady-state condition Eq. 7a leads to the expressions in Eq. 30a-b, and the equilibrium potential can be expressed according to Eq. 30c-d, in line with Eq. 7e, where the terms outside of the logarithm can be identified with the potential of the standard hydrogen electrode, denoted as 𝐸 𝐻 + /𝐻 2 ∘ :