Conducting electrochemical characterization

Electrochemical communication between electrode-bound enzyme and an electrode was confirmed by such electrochemical characterizations as differential pulse voltammetxy. As shown in Fig. 11, reversible electron transfer of molecularly interfaced FDH was confirmed by differential pulse voltammetry. The electrochemical characteristics of the polypyrrole interfaced FDH electrode were compared with those of the FDH electrode. The important difference between the electrochemical activities of these two electrodes is as follows by the employment of a conductive PP interface, the redox potential of FDH shifted slightly as compared to the redox potential of PQQ, which prosthetic group of FDH and the electrode shuttling between the prosthetic group of FDH and the electrode through the PP interface. In addition, the anodic and cathodic peak shapes and peak currents of PP/FDH/Pt electrode were identical, which suggests reversibility of the electron transport process. 

Bebelis S, Kotsionopoulos N, Mai A, Rutenbeck D, and Tietz F. Electrochemical characterization of mixed conducting and composite SOFC cathodes. Solid State Ionics 2006 177 1843-1848. 

In this chapter, two carbon-supported PtSn catalysts with core-shell nanostructure were designed and prepared to explore the effect of the nanostructure of PtSn nanoparticles on the performance of ethanol electro-oxidation. The physical (XRD, TEM, EDX, XPS) characterization was carried out to clarify the microstructure, the composition, and the chemical environment of nanoparticles. The electrochemical characterization, including cyclic voltammetry, chronoamperometry, of the two PtSn/C catalysts was conducted to characterize the electrochemical activities to ethanol oxidation. Finally, the performances of DEFCs with PtSn/C anode catalysts were tested. The microstmc-ture and composition of PtSn catalysts were correlated with their performance for ethanol electrooxidation. 

In addition to the criticisms from Anderman, a further challenge to the application of SPEs comes from their interfacial contact with the electrode materials, which presents a far more severe problem to the ion transport than the bulk ion conduction does. In liquid electrolytes, the electrodes are well wetted and soaked, so that the electrode/electrolyte interface is well extended into the porosity structure of the electrode hence, the ion path is little affected by the tortuosity of the electrode materials. However, the solid nature of the polymer would make it impossible to fill these voids with SPEs that would have been accessible to the liquid electrolytes, even if the polymer film is cast on the electrode surface from a solution. Hence, the actual area of the interface could be close to the geometric area of the electrode, that is, only a fraction of the actual surface area. The high interfacial impedance frequently encountered in the electrochemical characterization of SPEs should originate at least partially from this reduced surface contact between electrode and electrolyte. Since the porous structure is present in both electrodes in a lithium ion cell, the effect of interfacial impedances associated with SPEs would become more pronounced as compared with the case of lithium cells in which only the cathode material is porous. 

The topic of this book is focused on active masses containing carbon, either as an active mass (e.g., negative mass of lithium-ion battery or electrical double layer capacitors), as an electronically conducting additive, or as an electronically conductive support for catalysts. In some cases, carbon can also be used as a current collector (e.g., Leclanche cell). This chapter presents the basic electrochemical characterization methods, as applicable to carbon-based active materials used in energy storage and laboratory scale devices. 

For further electrochemical characterization of the conducting polymer films, the charge passed during the electrochemical synthesis can also be used to estimate the film thickness and level of doping, and thus the capacitance of the... 

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. 

Finally the conductivity and electrochemical activity of the polymer film, at the working potential used for driving the electrocatalytic reaction, is also essential for commentating on the observed electrocatalytic properties. Many experimental methods are available for such characterizations, such as electronic microscopies, electrical and electrochemical characterizations, which... 

A.Z. Ernst, S. Zoladek, K. Wiaderek, J.A. Cox, A. Kolaryzurowska, K. Miecznikowski, and P.T. Kulesza, Network films of conducting polymer-linked polyoxometalate-modified gold nanoparticles preparation and electrochemical characterization, Elctrochim. Acta, 53, 3924-3931 (2008). 

R. Mohs, Electrochemical Characterization of ionically conductive polymer membranes. Macromolecular Symposium 188 (2002) 73-89. 

Lehtinen T, Sundholm G, Holmberg S, Sundholm F, Bjornbom P, Bursell M (1998) Electrochemical characterization of PVDE-based proton conducting membranes for fuel cells, Electrcxhemica Acta 43 1881-1890. 

Analyses using an MS detector are also characterized by a very low matrix influence and are therefore ideally suitable for cases involving coelution, eluate interference, or sample matrix influence. This means that MS represents a real alternative to conventional IC detectors such as conductivity, electrochemical or UVA is detectors. Because of IC-MS coupling, direct quaUtative analysis of different species is possible. The mass-charge ratio is used for peak identification and resolving the molecular structure of the analyte. MS detection can be carried out in selected ion monitoring (SIM) or scan (m/z) mode. 

Mohna J, et al. Polyaniline coated conducting fabrics. Chemical and electrochemical characterization. Eur Polym J 2011 47 2003-15. 

For the electrochemical characterization, V(i) curves were recorded and an IR correction was used to compensate for the ohmic losses in the measured potential (the ohmic resistance was measured by current interruption). The slope of the V(i) curve (the surface-specific conductivity) was calculated as a characteristic parameter for the electrochemical performance of the anodes and the cathodes. 

Sanchez-Molas, D., Esquivel, J.R, Sabate, N. et al. (2012) High aspect-ratio, fully conducting gold micropillar array electrodes silicon micromachining and electrochemical characterization. J. Phys. Chem. C, 116,18831. 

Nowadays, sophisticated instrumentation, such as a potentiostat/galvanostat is commercially available for conducting electrochemical experiments for characterizing the electrochemical behavior a metal or an alloy in a few minutes. Nevertheless, a polarization diagram or curve is a potent control technique. This curve can experimentally be obtained statically or dynamically. The latter approach requires a linear potential scan rate to be applied over a desired potential range in order to measure the current response. 

Ozer N., Baretto T., Bu5mldimanli T., Lampert C.M. Characterization of sol-gel deposited niobium pentoxide films for electrochromic devices. Sol. Energy Mater. Sol. Cells 1995 36 433-413 Ozer N., Lampert C.M. Structural and optical properties of sol-gel deposited proton conducting Ta20s films. J. Sol-Gel Sd. TechnoL 1997 8 703-709 Ozer N., Lampert C.M. Electrochemical characterization of sol-gel deposited coatings. Sol. Energy Mater. Sol. Cells 1998 54 147-156... 

Further characterization on the DPE-HF coated samples was conducted by XPS analysis after immersion in NaCl solution used for electrochemical characterization confirmed this result. Two components at 399.3 (H-N-C = O) and 401.0 (N -R) eV in the XPS... 

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