Rapid drop time on-line Fast Fourier Transform faradaic admittance measurements

Zinc Oxidation in Dilute Alkaline Solutions Studied by Real-Time Electrochemical Impedance Spectroscopy

“…EIS measurements offer a strong tool for analyzing an electrified electrode–electrolyte interface as its electrical environment is as important as the nature of the chemical reactions taking place because the heterogeneous electron transfer occurs across the electrified interface. − Traditional EIS measurements have limitations due to the requirements that the system be in a stationary and equilibrated state, − and the measurements must thus be made after the stationary state has been reached upon applying a bias potential. Over the years, numerous efforts have been made for development of faster impedance measurement methods that may allow transient measurements to be made during other electrochemical experiments; earlier investigators used multisine techniques, − which have later been optimized for use along with cyclic voltammetric experiments. − The optimized techniques revealed a few limitations as well, however. We have recently developed a technique to obtain a series of impedance data during the potential sweep by combining Fourier transform electrochemical impedance spectroscopy (FTEIS) with the staircase cyclic voltammetry experiment, , in which a true white noise is used as an excitation signal .…”

Resolution of a Multi-Step Electron Transfer Reaction by Time Resolved Impedance Measurements: Sulfur Reduction in Nonaqueous Media

“…A more straightforward approach is to mix ac waves of known frequencies and apply the mixed signal packet to an electrochemical system. [13][14][15][16][17][18][19][20][21] The current signal obtained thereof is then resolved back into the ac current of each frequency by Fourier transform and used for impedance calculation. This method, first developed by Smith et al in the seventies,13-19 has been optimized recently thanks to recent advances in electronics and used during cyclic voltammetric scans by overlaying a signal packet on a sweep signal.20,21 Another technique takes advantage of the fact that a Dirac 8 function is made of ac waves of all frequencies with an identical initial phase and amplitude.22 Thus, the current obtained upon application of the 8 function to an electrochemical system would contain ac currents of all frequencies, leading to the calculation of impedances in a full frequency range.…”

Novel instrumentation in electrochemical impedance spectroscopy and a full description of an electrochemical system

“…The first series of efforts was made by Smith et al starting in the 1970s [13][14][15][16][17][18][19]. Their approach was based on the application of the mixed ac waves of many different frequencies superimposed on a desired dc bias potential to an electrochemical system, and the resultant current signal is deconvoluted into the component frequencies employing fast Fourier transform (FFT).…”