Rotating disk electrode theory

The theory of voltammetry with rotating disk electrode (RDE) was described in Sections 2.7.2 and 5.4.1. 

Eligh performance liquid chromatography Density functional theory Oxygen reduction reaction Rotating disk electrode Rotating ring disk electrode... 

The theory describing the mass transport to a rotating-disk electrode is due to Levich [8], who first presented an analytical solution for the flux to the electrode under laminar flow conditions (Re < 2.7x10 ). For the reaction of a minor ionic species B, the limiting current is given by equation (4.105), know as the Levich equation ... 

Anastasijevic, N.A., Vesovic, V., and Adzic, R.R. (1987) Determination of the kinetic parameters of the oxygen reduction reaction using the rotating-disk electrode. Part 1. Theory. J. Ekctroanal. Chem., 229, 305-316. 

The RDC has constituted the first decisive attempt to control the hydrod)mam-ics. This control was achieved by adaptation of the rotating-disk electrode used in electrochemistry. Description of the hydrodynamic motion of a fluid near a rotating disk was first approached by von Karman in 1921 [31] and it was reconsidered then by Levich [32], who extended this theory to convective-diffusive transport to a rotating disk. The Levich theory has been analyzed in detail subsequently and corrections have been proposed [33, 34], which however are commonly very small in practice. 

Nolan JE, Plambeck JA (1990) The EC-catalytic mechanism at the rotating disk electrode. Part II. Comparison of approximate theories for the second-order case and application to the reaction of bipyridinium cation radicals with dioxygen in non-aqueous solutions. J Electroanal Chem 294 1-20... 

The main objective of this chapter is to show that transport processes can significantly contribute to the electrochemical kinetics measurements and therefore should be taken into account. Transport processes are based on hydrodynamics (fluid mechanics), which is described with mathematics of the vector analysis. Students should know what the terms vector, gradient, and divergence represent. Solutions of Pick s second law of diffnsion are given as examples of hydrodynamics coupled with electrochemical kinetics. The theory and use of the rotating disk electrode (RDE) are explained. Introdnction to cyclic voltammetry (CV) techniques is also given. 

Tourwe, E., Pintelon, R. Hubin, A. (2006). Extraction of a quantitative reaction mechanism from linear sweep voltammograms obtained on a rotating disk electrode. Part I Theory and validation. Journal of Electroanalytical Chemistry 594(1) 50-58. 

The above problems may be alleviated by the use of a rotating hemispherical electrode (RHSE). In this geometry, the flat circular disk on the RDE is replaced with a metal hemisphere as shown in Fig. 1(a). The theory, experimental setup and methods of application to electrochemical studies are similar to those of the RDE. The advantages of the RHSE are ... 

With its axisymmetric transport and current distribution, the rotating hemispherical electrode complements the rotating disk as a tool for studying electrode processes. Der-Tau Chin provides a valuable overview and summary of the fundamental theory and applications of this interesting device. 

The Frumkin epoch in electrochemistry [i-iii] commemorates the interplay of electrochemical kinetics and equilibrium interfacial phenomena. The most famous findings are the - Frumkin adsorption isotherm (1925) Frumkin s slow discharge theory (1933, see also - Frumkin correction), the rotating ring disk electrode (1959), and various aspects of surface thermodynamics related to the notion of the point of zero charge. His contributions to the theory of polarographic maxima, kinetics of multi-step electrode reactions, and corrosion science are also well-known. An important feature of the Frumkin school was the development of numerous original experimental techniques for certain problems. The Frumkin school also pioneered the experimental style of ultra-pure conditions in electrochemical experiments [i]. A list of publications of Frumkin until 1965 is available in [iv], and later publications are listed in [ii]. 

It is our belief that a full and detailed understanding of the electron-transfer properties of organometallic complexes can be achieved only by a combination of chemical and electrochemical studies the use of one alone can lead to erroneous conclusions. Because we have insufficient space to provide a discussion of the theory and practice of elementary electrochemical techniques we refer the reader to several excellent treatments which also include an explanation of commonly used terminology (25-30). The synthetic chemist should not be deterred from routinely using techniques such as cyclic voltametry (CV),1 voltametry at rotating metal disk electrodes, or controlled potential electrolysis (CPE), coulometry, and chronoamperometry. The proper employment of such techniques, for which instrumentation is readily available, should prove sufficient for all but the most detailed studies. 

In standard RDE theory, one also assumes a negligible radial diffusion contribution to the current at the edges of the disk. This is true if the disk radius is sufficiently large that diffusion to it can be treated as simple linear diffusion. When the disk electrode radius falls in the ultramicroelectrode regime, this is no longer the case, so different equations will apply to the rotating microdisk, as discussed in Section 9.7. 

Theory of Rotating Ring-Disk Electrode Technique 200... 

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