Fundamental Principles of Organic Electrochemistry: Fundamental Aspects of Electrochemistry Dealing with Organic Molecules - Fundamentals and Applications of Organic Electrochemistry - page 19

potential ( E o′ ). The relationship between E o
and E o′ is represented by Eq. 2.3 :
(2.3)
where γ O and γ R are the activity coefficients for
the oxidized and reduced forms of a studied
species. However, the deviation between E o and
E o′ is very small in a dilute solution and is
usually less than 300 mV even in a
concentrated solution.
The potential at the peak of CV curves is termed
the peak potential. For the reversible redox
reaction, the anodic peak potential ( E pa ) and
cathodic peak potential ( E pc ) are independent
of scan rate and concentration, therefore the
peak potentials supply information about the
identity of the substrate species and the
thermodynamic index for the oxidation/
reduction of the studied species. In addition,
the average value of the anodic and cathodic
peak potentials corresponds to the formal
reduction potential ( E o′ ) for a reversible couple
( Figure 2.5 ).