DC polarography: Effects of electrode sphericity on the current—Potential curves with EC and CE mechanisms

Advances in Derivative Voltammetry - A Search for Diagnostic Criteria of Several Electrochemical Reaction Mechanisms

“…As far as analysis of the derivatives concerned, most of the work have dealt with only the linear diffusion (on a planar electrode) or semi-infinite liner diffusion (on DME, or SMDE), not with spherical diffusion (on a spherical electrode), even though there are many studies on the original currents (not derivatives) with spherical electrodes from earlier days of polarographic/voltammetric works as given in general monographs [30,38,43,44] as well as in articles on particular systems and methods [45][46][47][48][49][50][51][52][53][54][55]. These include studies on EC mechanisms [45,46], CE mechanisms [46,47,54], on various pulse polarographic methods [48,55], on DC polarography [49], on AC polarography [72], on cyclic voltammetry [51], on catalytic EC mechanism with the square-wave voltammetry [52], on a double potential method [53] and on DPV at spherical and microelectrodes [56].…”

EChem++ – An object-oriented problem solving environment for electrochemistry. Part 6. Adaptive finite element simulations of controlled-current electrochemical experiments

“…The use of simulation techniques does not yield explicit expressions between control parameters and response. Therefore, the effects of the parameters on the outcome cannot be observed and evaluated in a direct way (see, e.g., [10]) as in the analytical solution. However, if both solution strategies are possible, the analytical and numerical approaches are complementary, and may be used to check consistency of the results.…”

Analysis of the first-order EC process by direct current and derivative polarography

“…For example, the early analytical approach by Kern (1) is valid only for E> E°and k > 7, and his theoretical treatment predicts a reversible slope for E vs. log [(¿d -i)/i] plot which disagrees with the experimental observiations. This discrepancy has not been clarified and deserves further investigation although Galvez and co-workers recently reported (19,20) the current-potential curves for a reversible electron transfer coupled with a reversible follow-up chemical reaction (ErCr process). As the systems get more involved, finite difference methods (21) and other methods of approximation (22) have become more popular than exact analytical approaches for the solutions of the second-order partial differential equations associated with particular boundary conditions.…”

“…The study of a reversible electrode reaction which is coupled with an irreversible follow-up homogeneous reaction (an ECtype mechanism, or ErC¡ more specifically) has been a subject of much research effort (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20) during the last several decades because it is one of the more common types of processes encountered in electrode kinetics. Examples of this type of mechanism appear in the oxidation of ascorbic acid (1) and aminophenols (2) and the reduction of azines (9), azo dyes (4, 17), and certain radicals (15), etc.…”

“…The current expression for derivative polarography can be found by differentiating eq [17][18][19] with respect to the potential. For E > E°, from eq 17 and 20…”