Relation between adsorption and electrochemical impedance in anodic dissolution of metal

The relations between various adsorbed processes and electrochemical impedance in metal dissolution have been discussed on the basis of numerical analyses. The modulation of adsorption coverage Delta theta/Delta E is represented as the function of angular frequency omega in the frequency domain: Delta theta/Delta E=alpha theta(1)/(j omega alpha theta(2)+1), where alpha(1) is a constant. Moreover, the admittance A(F) and impedance Z are related to the Delta theta/Delta E:A(F)=alpha(A1)+alpha(A2)Delta theta/Delta E, 1/Z=A(F)+j omega C-d1, where C-d1 is capacitance of electric double layer. The presences of adsorbed species yield the unique loci of Z on the complex plane, i.e., inductive loop and negative resistance. The inductive loop appears in the three kinds of adsorption in the metal dissolution, i.e., (i) adsorbed intermediate, (ii) catalytic adsorbed species, and (iii) cathodic adsorbed species.