Itagaki Masayuki, Taya Akihiro, Watanabe Kunihiro, Noda Kazuhiko
Department of Pure and Applied Chemistry, Faculty of Science and Technology, Tokyo University of Science, Noda, Chiba, Japan.
Anal Sci. 2002 Jun;18(6):641-4. doi: 10.2116/analsci.18.641.
The electrochemical impedance of an iron electrode often shows the capacitive and inductive loops on the complex plane. The capacitive loop originates from the time constant of the charge transfer resistance and the electric double layer capacitance. The inductive loop is explained by Faradaic processes involving the reaction intermediate. In some cases, these loops deviate from a true semicircle. In this paper, the origins and curve-fitting methods for the deviated loops of electrochemical impedance are discussed. The constant phase element (CPE) was used to present the deviation of the capacitive loop instead of electric double layer capacitance. The reaction rate constants, which are a function of the frequency, are proposed for the Faradaic impedance to present the deviated inductive loop.
铁电极的电化学阻抗在复平面上常常呈现出电容性和电感性回路。电容性回路源于电荷转移电阻和双电层电容的时间常数。电感性回路则由涉及反应中间体的法拉第过程来解释。在某些情况下，这些回路会偏离真正的半圆。本文讨论了电化学阻抗偏离回路的起源和曲线拟合方法。使用恒相位元件（CPE）来表示电容性回路的偏差，而不是双电层电容。针对法拉第阻抗提出了作为频率函数的反应速率常数，以呈现偏离的电感性回路。
