Electrochemical impedance characterization

Hu, C.-C., and C.-H. Chu. 2001. Electrochemical impedance characterization of polyaniline-coated graphite electrodes for electrochemical capacitors—Effects of film coverage/thickness and anions. 7 Electroanal Chem 503 105. 

The UPD and anodic oxidation of Pb monolayers on tellurium was investigated also in acidic aqueous solutions of Pb(II) cations and various concentrations of halides (iodide, bromide, and chloride) [103]. The Te substrate was a 0.5 xm film electrodeposited in a previous step on polycrystalline Au from an acidic Te02 solution. Particular information on the time-frequency-potential variance of the electrochemical process was obtained by potentiodynamic electrochemical impedance spectroscopy (PDEIS), as it was difficult to apply stationary techniques for accurate characterization, due to a tendency to chemical interaction between the Pb adatoms and the substrate on a time scale of minutes. The impedance... 

Examination of the membranes with a variety of physicochemical techniques, from related electrochemical approaches (as electrochemical impedance spectroscopy (EIS), voltammetry and chronoamperometry) to more sophisticated characterization methods (spectroscopy and microscopy), actually serves the same end as the theory and leads to a deeper understanding of the chemistry behind the functioning of these sensors [5, 6],... 

The monotonic increase of immobilized material vith the number of deposition cycles in the LbL technique is vhat allo vs control over film thickness on the nanometric scale. Eilm growth in LbL has been very well characterized by several complementary experimental techniques such as UV-visible spectroscopy [66, 67], quartz crystal microbalance (QCM) [68-70], X-ray [63] and neutron reflectometry [3], Fourier transform infrared spectroscopy (ETIR) [71], ellipsometry [68-70], cyclic voltammetry (CV) [67, 72], electrochemical impedance spectroscopy (EIS) [73], -potential [74] and so on. The complement of these techniques can be appreciated, for example, in the integrated charge in cyclic voltammetry experiments or the redox capacitance in EIS for redox PEMs The charge or redox capacitance is not necessarily that expected for the complete oxidation/reduction of all the redox-active groups that can be estimated by other techniques because of the experimental timescale and charge-transport limitations. 

Akikusa J, Khan SUM (1997) Photo response and AC impedance characterization of n-Ti02 during hydrogen and oxygen evolution in an electrochemical cell. Int J Hydrogen Energy 22 875-882... 

Vogt, O., Grass, B., Weber, G., Hergenroder, R., Siepe, D., Neyer, A., Pohl, J.P., Characterization of sputtered thin film electrodes on PMMA microchips with electrochemical impedance spectroscopy and cyclic voltammetry. Micro Total Analysis Systems, Proceedings 5th lTAS Symposium, Monterey, CA, Oct. 21-25, 2001, 327-328. 

Characterization by Electrochemical Impedance Spectroscopy of Porous Electrodes... 

The impedance spectroscopy is most promising for electrochemical in situ characterization. Many papers have been devoted to the AB5 type MH electrode impedance analysis [15-17]. Prepared pellets with different additives were used for electrochemical measurements and comparing. Experimental data are typically represented by one to three semicircles with a tail at low frequencies. These could be described to the complex structure of the MH electrode, both a chemical structure and porosity [18, 19] and it is also related to the contact between a binder and alloy particles [20]. The author thinks that it is independent from the used electrolyte, the mass of the electrode powder and the preparing procedure of electrode. However, in our case the data accuracy at high frequencies is lower in comparison with the medium frequency region. In the case, the dependence on investigated parameters is small. In Figures 3-5, the electrochemical impedance data are shown as a function of applied potential (1 = -0.35V, 2 = -0.50V and 3 = -0.75V). 

Electrochemical impedance spectroscopy (EIS) is a powerful tool for examining the processes occurring at the electrode surfaces. EIS is a kind of electrochemical analysis method which can be used in the characterization of batteries, fuel cells, and corrosion phenomena. 

EIS data extrapolation, uses neural networks to train on electrochemical impedance spectroscopy data for extrapolation Filter debris analysis (FDA) expert system, condition monitoring of aircrafts GENERA, generic problem-solving framework for characterizing corrosion and materials problems LipuCor, prediction of corrosion in oil and gas systems... 

Although electrochemical characterizations have recently been performed on single intercalation particles, in most cases composite powdery electrodes containing a mixture of intercalation particles, electrically conductive additives (e.g., carbon black) and PVDF binder have also been used. In order to obtain consistent results and to reach comprehensible intercalation mechanisms in these electrodes, basic electroanalytical characterizations such as slow-scan rate -> cyclic voltammetry (SSCV), -> potentiostatic intermittent titration (PITT) (or -> galvanostatic intermittent titration, GITT), and -> electrochemical impedance spectroscopy (EIS) should be applied in parallel or in a single study. 

Finite-space diffusion takes place during the charging of insertion electrodes at moderate frequencies, transforming into mainly capacitive behavior within the limit of very low frequencies, in contrast to the semi-infinite diffusion for solution redox-species (except for thin-layer solution electrochemistry) electrochemical impedance spectroscopy becomes a very useful diagnostic tool for the characterization of insertion mechanisms ... 

Figure C.l. K-K transforms of real and imaginary components of the electrochemical impedance for passive zinc in a borate solution of pH = 10.5, at 1.2 V (SCE) [13]. (Reproduced by permission of ECS—The Electrochemical Society, from Ismail KM, Macdonald DD. Characterization of the barrier passive film on zinc.)...

Although simple impedance measurement can tell the existence of an anodic film, electrochemical impedance spectroscopy (EIS) can obtain more information about the electrochemical processes. In general, the anode/electrolyte interface consists of an anodic film (under mass transport limited conditions) and a diffuse mobile layer (anion concentrated), as illustrated in Fig. 10.13a. The anodic film can be a salt film or a cation (e.g., Cu ) concentrated layer. The two layers double layer) behave like a capacitor under AC electric field. The diffuse mobile layer can move toward or away from anode depending on the characteristics of the anode potential. The electrical behavior of the anode/electrolyte interface structure can be characterized by an equivalent circuit as shown in Fig. 10.13. Impedance of the circuit may be expressed as... 

Woo, L.Y., Martin, L.P., Glass, R.S. and Gorte, R.J. (2007) Impedance characterization of a model Au/yttria-stabilized zirconia/Au electrochemical cell in varying oxygen and NO concentration./. Electrochem. Soc., 154 (4), J129-35. 

Electrochemical impedance spectroscopy (EIS) or ac impedance methods have seen a tremendous increase in popularity in recent years. Initially applied to the determination of the double-layer capacitance " and in ac polarography, " they are now used to characterize electrode processes and complex interfaces. This method studies the system response to the application of a periodic small-amplitude ac signal. The measurements are carried out at different ac frequencies and thus the name impedance spectroscopy was later adopted. Analysis of the system response contains information about the interface, its structure, and the reactions taking place there. Electrochemical impedance spectroscopy is now described in the... 

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