Metal film electrode

When a solid electrolyte component is interfaced with two electronically conducting (e.g. metal) films (electrodes) a solid electrolyte galvanic cell is formed (Fig. 3.3). Cells of this type with YSZ solid electrolyte are used as oxygen sensors.8 The potential difference U R that develops spontaneously between the two electrodes (W and R designate working and reference electrode, respectively) is given by ... 

Owing to the toxicity of mercury and its disposal problem, solid electrodes are now very popular. In particular, electrodes made of carbon such as glassy carbon, graphite, carbon paste, and carbon fibers have gained popularity. Mercury, gold, bismuth, and other metals can be deposited as thin metal films on carbon and serves as thin metal film electrodes (TMFE) with excellent analytical advantages in trace metal analysis. The choice of working electrode is determined by the redox... 

Silicon rubber gasket electrode electrode Teflon cell Metal-film electrode... 

In the internal reflection method a light ray is incident from the interior side of an electrode to the interface. Optically transparent electrodes (OTE), such as tin oxide, metal film electrodes in the visible region, are used to obtain absorption spectra of adsorbed species by multiple reflection (Hansen, 1973 Heinemanetal., 1984 Kuwanaand Winograd, 1974 Mark and Randall, 1970). 

Quartz Crystal Microbalance. This experiment depends on the manner in which the resonant frequency of an oscillating quartz crystal piezoelectric element responds to a change in mass on the Interface perpendicular to the oscillatory motion. Typically the oscillation is excited between facing metal film electrodes on opposite side of the crystal as shown in Figure 2(top). A change in mass at one of the Interfaces produces a proportional oscillatory frequency decrease. 

The (nonelectrochemical) SEIRAS effect was first reported by Hartstein and coworkers in 1980 [110], after which Suetaka and coworkers published a number of papers from 1982 exploiting Kretschmann coupling (Fig. la) to effect SPP excitation and the concomitant enhancement of the infrared absorptions of species adsorbed at the thin metal film electrode surface [69, 111-113], effectively SEIRAS. The authors commented that the short-range enhancement afforded by the technique enabled species at the metal-aqueous solution interfaces to be preferentially observed . Similarly, Neff and coworkers [48] reported the study of water at the electrode-electrolyte interface using SPP excitation. As with the SERS effect, SEIRAS is limited, so far, to the coinage metals [5,10]. 

Metal oxides Being frequently assessed as modifiers for CPEs, their way of action may account for different purposes. Some are electrocatalysts due to a potential-dependent change of their valence state [130-133]. Another interesting approach is to add them directly to the paste as precursors for metal film electrodes which renders plating with a solution of the metal obsolete (e.g., [134]). 

The theory and experiments we have described suggest some experimental guidelines and protocols that will enhance the quality and analysis of ILIT responses—some will be obvious to the electrochemical practitioner some may not be. The following suggestions presume that the thickness of the metal film electrode is uniform and accurately known and that the SAM itself has been appropriately characterized. 

Voegel, P.D. Zhou, W. Baldwin, R.P. Integrated Capillary Electrophoresis/Elec-trochemical Detection with Metal Film Electrodes Directly Deposited onto the Capillary Tip. Anal. Chem. 1997 69, 951-957. 

EQCM [172] significantly contributed to the elucidation of mechanisms of electrochemical reactions of fullerene films. The principle of the method is simple and based on frequency measurement of a piezoelectric quartz crystal. The frequency is sensitive to mass and viscosity changes on a thin metal film (electrode) deposited on the quartz crystal. Most commonly any contribution from shear forces is neglected and the observed fi-equency changes are regarded as being... 

Electrode modification of these bulk materials is the major topic to be treated in the next sections. We will see that the range of modification that has been considered is quite large, with the deposition of metal film electrodes, the electrode texturation (for increasing the electrode surface area with respect to the geometric one), the functionalization with organic monolayers or polymeric multilayers, or the elaboration of composite electrode materials for the development of sensors for possible application in the field of environmental analysis. 

Within common heavy metals, certain specificity can be attributed to copper and mercuiy, due to their nobler character and somewhat different behaviour compared to the previous metals. Namely, Cu ions (or Cu species, respectively) can be reduced to the metal in one-electron steps in alkaline media, Cu +e Cu +e and, in the same way, re-oxidised. Some of the metals may form intermetaUic adducts that may seriously interfere in many determinations using ESA, especially, at metallic film electrodes." ... 

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