Vibrational techniques electrode technique

D.A. Worsley, H.N. McMurray, A. Belghazi, Determination oflocalized corrosion mechanisms using a scanning vibrating reference electrode technique, Chem. Commun. (1997) 2369—2370. 

SVRET scanning vibrating reference electrode technique... 

As electrochemical measurements are of particular importance for corrosion studies, this chapter will only concentrate on them. However, since many textbooks and monographs discuss the earlier-mentioned simple analysis of current-voltage plots, this discussion will not be covered here. In recent years, more sophisticated techniques have been developed, and these partly overcome the restrictions of conventional electrochemical measurements as they either provide only a small potential perturbation on the corroding system (impedance spectroscopy), use no perturbation at all (electrochemical noise analysis), are able to measure current and potential fluctuations on inhomogeneous corroding surfaces (vibrating electrochemical electrode techniques), or... 

Many important processes such as electrochemical reactions, biological processes and corrosion take place at solid/liquid interfaces. To understand precisely the mechanism of these processes at solid/liquid interfaces, information on the structures of molecules at the electrode/electrolyte interface, including short-lived intermediates and solvent, is essential. Determination of the interfacial structures of the intermediate and solvent is, however, difficult by conventional surface vibrational techniques because the number of molecules at the interfaces is far less than the number of bulk molecules. 

Scanning electrochemical microscopy (SECM) - Direct mode - Feedback mode - Generation/collection mode Scanning reference electrode technique (SRET) Scanning vibrating electrode technique (SVET) Scanning photoelectrochemical microscopy (SPECM) Scanning electrochemical induced desorption (SECMID)... 

Distinct from the previous methods employed, the vibrating probe electrode (VPE) allows determination of the magnitude and direction of current flow, in real time [63]. The magnitude of the measured current is, of course, a sum over all transported ionic species. Thus, this technique permits the unique patterns of current distribution across the skin to be identified, but not, however. 

The scanning vibration electrode technique (SVET), providing a map of the current density, allows demonstration of the termination of the corrosion process under irradiation. Fig. 2a shows the corrosion current map recorded after 36 h of immersion of the SiOx ZrOx film with IR-laser light sensitive BSA-loaded nanocontainers Ti02 Ag/PEI/PSS/PEI/PSS. Before immersion, the film was... 

Recently, two new electrochemical mapping techniques have become available the scanning vibrating electrode technique (SVET) and the localized electrochemical impedance spectroscopy (LEIS) technique. These techniques provide the capability to identify and monitor electrochemical behavior down to the micron level. These represent significant advances over traditional electrochemical methods (cyclic voltammetry, EIS, and even EQCM), which provide data that reflect only an average over the entire sample surface. Although such data are very useful, a major drawback is that no local or spatial information is obtained. 

One can obtain vibrational spectra of only adsorbed species by taking advantage of the nonlinear effects at the interface discussed in Section 17.1.5 in connection with SHG. In the vibrational region, the technique is called sum frequency generation (SFG) and is carried out by irradiating the electrode/solution interface with a visible beam at a fixed frequency. 

The scanning vibrating electrode technique (SVET) uses a microelectrode capable of measuring potential gradients in the corrosion solution near localized corrosion. It locates and measures corrosion at specific points of the corroding surface [9]. This technique performs in situ locahzed corrosion measurements occurring on the surface. During the measurement, the microelectrode vibrates perpendicular to the surface. The tip of the... 

H.S. Isaacs, The measurement of the galvanic corrosion of soldered copper using the scanning vibrating electrode technique, Corros. Sci. 28 (1998) 547—558. 

Isaacs H. The use of the scanning vibrating electrode technique for detecting defects in ion vapor-deposited aluminium on steel. Corrosion, 43, 1987 10 594-598. 

M.J. Frankhn, D.C. White, H. Isaacs. Pitting corrosion by bacteria on carbon steel, determined by the scanning vibrating electrode technique. Corrosion Science, Vol. 32, No. 9, pp. 945-952, 1991. 

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