Caution of Using Constant Phase Element

摘要

Nyquistplots of electrochemical impedance spectroscopy (EIS) data frequently exhibit non-ideal behavior, such as depressed semicircles and capacitive straight lines not perpendicular to the real axis. This non-ideal behavior is commonly attributed to non-homogeneity of the electrochemical system. A constant phase element (CPE) is often employed to improve the fit of a proposed equivalent circuit model to the data.