Electrochemical measurements, metal vapor

Electric arcs, in metal vapor synthesis, 1, 224 Electric-field-induced second harmonic generation Group 8 metallocenes, 12, 109 for hyperpolarizability measurement, 12, 107 Electrochemical cell assembly, in cyclic voltammetry, 1, 283 Electrochemical irreversibility, in cyclic voltammetry, 1, 282 Electrochemical oxidation, arene chromium carbonyls, 5, 258 Electrochemical properties, polyferrocenylsilanes, 12, 332 Electrochemical reduction, bis-Cp Zr(III) and (IV) compounds, 4, 745 Electrochemical sensors biomolecule—ferrocene conjugates... 

In a typical spectroelectrochemical measurement, an optically transparent electrode (OTE) is used and the UV/vis absorption spectrum (or absorbance) of the substance participating in the reaction is measured. Various types of OTE exist, for example (i) a plate (glass, quartz or plastic) coated either with an optically transparent vapor-deposited metal (Pt or Au) film or with an optically transparent conductive tin oxide film (Fig. 5.26), and (ii) a fine micromesh (40-800 wires/cm) of electrically conductive material (Pt or Au). The electrochemical cell may be either a thin-layer cell with a solution-layer thickness of less than 0.2 mm (Fig. 9.2(a)) or a cell with a solution layer of conventional thickness ( 1 cm, Fig. 9.2(b)). The advantage of the thin-layer cell is that the electrolysis is complete within a short time ( 30 s). On the other hand, the cell with conventional solution thickness has the advantage that mass transport in the solution near the electrode surface can be treated mathematically by the theory of semi-infinite linear diffusion. 

In early in-situ infrared spectroscopy studies of catalyst supported on reflective Au substrates, it was recognized that spectral bands develop distortions due to anomalous optical effects as the catalyst coverage becomes greater than a few monolayers [17, 18, 158]. Different procedures were adopted to ensure that catalyst coverages on Au remained low [15, 17, 18, 157, 158]. Related to these efforts are experiments that examine the electrochemical and optical properties of nanostructured metal electrodes prepared by chemical, vapor, or electrochemical deposition methods (cf. Refs. [79, 137, 141, 170-179] and references therein). Much of the work in this area has targeted SEIRAS measurements. 

Another issue for applying metals to the interconnectors is the vaporization of Cr from the alloys [12, 13]. Even though the Cr vapor pressures are reduced by the formation of Cr203 oxide scales, a small amount of vapor pressures of Cr was measured, which was lower than 10 atm levels at 1,073 K (10 ppb levels). Cr vapors can be transported to cathode and deposited at the active sites of oxygen reduction. Because the reduction of Cr valence in C1O3 vapor occurs (Cr " —> Cr " + 3e ) at the electrochemical active sites. This reaction is represented in the following reaction ... 

Fucsko,J.,Tan, S. S-, and Balazs, M. K. (1993). Measurement of trace metallic contaminents on silicon wafer surfaces in native and dielectric silicon oxides by vapor-phase decomposition flow injection inductively coupled plasma-mass spectrometry. J. Electrochem. Soc. 140(4), 1105. 

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