WOLFRAM|DEMONSTRATIONS PROJECT

Nonlinear Impedance of Tafelian Electrochemical Systems

​
log(
R
S
) (Ω)
0.85
V (V)
0.25
log(f) (Hz)
1.8
δ V (V)
0.1
This Demonstration shows the effects of Tafel kinetics, ohmic potential drop, interfacial capacitance, and amplitude/frequency of sinusoidal potential signals on the nonlinear impedance of electrochemical systems.
The plots show (a) steady-state polarization curve (
I-V
) and curve (
I-E
) corrected for ohmic drop; (b) Lissajous plot under sinusoidal perturbation of potential; (c) potential perturbation and effective interfacial potential scaled by input signal amplitude; (d) periodic current and its fundamental component; (e) faradaic and capacitive contributions to the total current; and (f) Nyquist plots of the usual (linear) impedance (
Z
) and the nonlinear impedance (
Z
nl
), scaled by the low-frequency linear resistance.