After performing the corrosion test by the electrochemical impedance spectroscopy manner (EIS) between an average of 10 kHz - 10 Hz. We extract the necessary parameters such as Rct ( transfer charge resistance),...
But, rarely where we find the determination of the high frequency of each concentration used?
Why we don't determine it? And in which kind of interpretation we might need it?
Question from my side: Corrosion tests with EIS down to only 10 Hz? Isn't that actually still too fast for charge transfer reactions?
Dear DAyoub Najem
I agree with you in that the dependence of the impedance on the frequency of the applied signal is not always shown directly since this function is important only to investigate how much the under test system is deviating from the ideal behavior. in this respect the symmetric dependence of Z” with respect to fmax is practically considered as ideal behavior as the integration plot of Z” in terms of log f produce a sharp maximum of Z”max at fmax . Such observation, becomes less pronounced as the system deviates from the assumed ideal behavior and so this anomalous phenomenon is attributed to the non-homogeneity of the electrode surface arising from the surface roughness or interfacial phenomena as the inhibitor adsorbs to form a very incomplete layer.
Now you can obtain fmax by searching the data by excel command for the maximum value in the Z'' column and take the corresponding frequency and recorded it as fmax for each inhibitor concentration.
Best regards
Article Inhibitory effect of Acacia hamulosa methanolic extract on t...