Rotating gold electrode

Y. Bonfil, M. Brand and E. Kirowa-Eisner, Trace determination of mercury by anodic stripping voltammetry at the rotating gold electrode, Anal. Chim. Acta, 424 (2000) 65-76. 

Notes DP-ASV, differential-pulse anodic stripping voltammetry RDE-Au, rotating gold electrode HG-AAS, /tydride generation atomic absorption spectrometry FA AS, /lame atomic absorption spectrometry FI-CV-AAS, /low-injection cold-vapor atomic absorption spectrometry and HMDE, /tanging mercury drop electrode. 

Yeager and co-workers [379, 419] studied the kinetics of peroxide decomposition on dispersed oxide powders by measuring changes in the convective-diffusion limiting current for peroxide oxidation at a rotating gold electrode immersed in the liquid dispersion. The current decay was observed to be proportional to the peroxide concentration decay due to the catalytic decomposition process. On perovskite [379] and spinel oxides [419], it follows first-order kinetics described by the equation... 

Andrews RW, Johnson DC (1975) Voltammetiic deposition and stripping of selenium(lV) at a rotating gold-disk electrode in 0.1 M perchloric acid. Anal Chem 47 294-299... 

Traore M, Moddo R, Vittori O (1988) Electrochemical behaviour of tellurium and silver teUuride at rotating glassy carbon electrode. Hectrochim Acta 33 991-996 Ngac N, Vittori O, Quarin G (1984) Voltammetrie and chronoamperometric studies of tellurium electrodeposition of glassy carbon and gold electrodes. J Electroanal Chem 167 227-235... 

Bhzanac BB, Arenz M, Ross PN, Markovic NM. 2004b. Surface electrochemistry of CO on reconstructed gold single crystal surfaces studied by infrared reflection absorption spectroscopy and rotating disk electrode. J Am Chem Soc 126 10130-10141. 

Fig. 24 (a) 1,5-Dinitro-anthracene connected to two monoatomic gold electrodes. The Tight Binding model used to study this system is represented underneath, (b) Modifications of the MO induced by the rotation of the nitro groups... 

The rotating disc electrode is constructed from a solid material, usually glassy carbon, platinum or gold. It is rotated at constant speed to maintain the hydrodynamic characteristics of the electrode-solution interface. The counter electrode and reference electrode are both stationary. A slow linear potential sweep is applied and the current response registered. Both oxidation and reduction processes can be examined. The curve of current response versus electrode potential is equivalent to a polarographic wave. The plateau current is proportional to substrate concentration and also depends on the rotation speed, which governs the substrate mass transport coefficient. The current-voltage response for a reversible process follows Equation 1.17. For an irreversible process this follows Equation 1.18 where the mass transfer coefficient is proportional to the square root of the disc rotation speed. 

The authors [373] have studied the effect of prolonged cathodic polarization at negative potentials (E < 0.00 V) using both gold wire and rotating disc electrodes. They have shown that Au electrode prepolarized at —0.60 V for 20 min reveals in... 

Dissolution of gold and silver from Au/Ag alloys in aerated cyanide solutions has been investigated using rotating disc electrodes [551]. Dissolution was partially controlled by transport of either oxygen or cyanide. Kinetics of anodic dissolution of gold in cyanide solutions containing different metal ions has been extensively... 

Sun et al. [382] have studied the dissolution behavior of gold and silver from Au—Ag alloys in aerated cyanide solutions using rotating disc electrodes. 

Cys is an amino acid of great interest and its redox behavior is influenced by the electrode materials, and buffer and electrolyte conditions. S-Based oxidation results in the formation of sulfinic or sulfonic acids. The electrochemical oxidation takes place in two irreversible steps at gold and platinum rotating disc electrodes at peak... 

Rotating optically semii-transparent electrodes for spectroelectro-chemical or photoelectrochemical studies can be fabricated by vapour deposition techniques on a quartz substrate. In this way, tin oxide, platinum and gold electrodes, amongst others, can be made. Electrical contact is with silver paint. 

Figure 4 Comparison of the anodic behaviour of a rotating disc gold electrode in 0.1 M KOH with that in a solution of 0.1 M KOH and 0.1 M KCN (after Nicol, ref. 18)...

The application of surface-enhanced Raman spectroscopy (SERS) for monitoring redox and other processes at metal-solution interfaces is illustrated by means of some recent results obtained in our laboratory. The detection of adsorbed species present at outer- as well as inner-sphere reaction sites is noted. The influence of surface interaction effects on the SER spectra of adsorbed redox couples is discussed with a view towards utilizing the frequency-potential dependence of oxidation-state sensitive vibrational modes as a criterion of reactant-surface electronic coupling effects. Illustrative data are presented for Ru(NH3)63+/2+ adsorbed electrostatically to chloride-coated silver, and Fe(CN)63 /" bound to gold electrodes the latter couple appears to be valence delocalized under some conditions. The use of coupled SERS-rotating disk voltammetry measurements to examine the kinetics and mechanisms of irreversible and multistep electrochemical reactions is also discussed. Examples given are the outer- and inner-sphere one-electron reductions of Co(III) and Cr(III) complexes at silver, and the oxidation of carbon monoxide and iodide at gold electrodes. 

To get relevant information about active materials, the working electrode is made as similar as possible to the electrode of an operational device. However, current collectors are usually made with corrosion resistant materials, with good electronic conductivity, and no concern is taken about its relative mass. Materials such as gold, platinum, and vitreous carbon are commonly used. The active mass is usually tested in small amounts, mixed with electronically conducting materials, such as acetylene black, and a binder, such as poly vinylidene fluoride PVDF or polytetrafluoroethylene. The working electrode may be flat, with a 1 cm2 surface, for example, a rotating disk electrode (RDE), or a microcavity electrode, or any geometrical convenient electrode. 

Another example of a similar rotating disc electrode with an EQCM has been reported by Ritchie et al. [22] for the study of gold and copper dissolution during the electroreduction of oxygen in alkaline cyanide solutions. 

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