Byoung-Yong Chang*
Department of Chemistry, Pukyong National University, 45 Yongso-ro, Nam-gu, Busan 608-739, Korea
Here I report on how Fourier Transform Electrochemical Impedance Spectroscopy
(FTEIS) overcomes the potential-current linearity problem encountered in the impedance calculation
process. FTEIS was first invented to solve the time-related drawback of the conventional
impedance technique. The dramatic time reduction of FTEIS enabled the real-time
impedance measurement but brought about the linearity problem at the same time. While the
conventional method circumvents the problem using the steady-state made by a sufficiently long
measurement time, FTEIS cannot because of its real-time function. However, according to the
mathematical development reported in this article, the potential step used in FTEIS is proved
to avoid the linearity problem. During the step period, the potential and the current are linearized
by the electrochemical impedance. Also, Fourier transform of the differentiated potential
and current is proved to give the same result of the original ones.
Keyword : Impedance Spectroscopy, Electrochemistry Theory, Warburg Impedance