| dc.description.abstract | My first practical contact with electrochemical impedance spectroscopy (EIS)
was during my postdoctoral training in the laboratory of Prof. Ron W. Fawcett
at the University of Guelph, Ontario, Canada, in 1975. At that time I was using ac
voltammetry on a dropping mercury electrode. Since then, the technique and
equipment have evolved significantly. I was continually using EIS in subsequent
years in the kinetics of the reduction of metal cations in nonaqueous solvents to
determine the kinetics of hydrogen evolution, adsorption and absorption into
metals, impedance of porous electrodes, and electrocatalytic reactions. After a
series of seminars on the impedance spectroscopy in the laboratory of Prof. Brian
Conway in Ottawa in 1994, he encouraged me to write a review in Modern Aspects
of Electrochemistry, which was published in 1999. Prof. Conway has also asked me
to write a second chapter in Modern Aspects on the impedance of hydrogen
adsorption, absorption, and evolution (2002). Later, Prof. M. Schlesinger asked
me to write yet another chapter on the impedance of porous electrodes (2009). This
book originated from my previous reviews and lectures at various universities.
The purpose of this book is to present the concept of impedance, impedance
of electrical and electrochemical systems, its limitations, and certain applications.
The available books on EIS were written either by physicists or engineers, and I
wanted to present it from the chemist’s point of view. Some knowledge of electrochemistry
is necessary to understand the developments of kinetic equations. I hope
that it will be useful to students who are just starting to use this technique and to
others already using it in their research. The book contains theory and applications,
numerical examples shown in the text, and exercises with full solutions on the
Internet.
First, electrical circuits containing resistances only are presented, followed by
circuits containing R, C, and L elements in transient and ac conditions. To understand
the concept of impedance, the notions of Laplace and Fourier transforms
are presented and must be understood thoroughly. In this chapter, impedance plots
are also presented, along with several examples for various circuits. Next, methods
for determining impedances, including fast Fourier transform-based techniques, are
discussed. | en_US |
