Potential sweep methods electrochemistry

T. R. Mueller and R. N. Adams (see R. N. Adams, Electrochemistry at Solid Electrodes, Marcel Dekker, New York, 1969, p. 128) suggested that by measurement of ip/v for a nemstian linear potential sweep voltammetric curve, and by carrying out a potential step experiment in the same solution at the same electrode to obtain the limiting value of it, the n value of an electrode reaction can be determined without the need to know A, C, or Dq. Demonstrate that this is the case. Why would this method be unsuitable for irreversible reactions ... 

Figure 6.12 Linear-sweep voltammogram for the reduction reaction, O - - ne" —> R, at a solid electrode, shown as a function of the scan rate u. The solution was under diffusion control, which was achieved by adding inert electrolyte and maintaining a still solution during potential ramping. Note that the x-axis has been normalized to , that is, thex-axis represents an overpotential. Reproduced from Greef, R., Peat, R., Peter, L.M., Pletcher, D. and Robinson, J., Instrumental Methods in Electrochemistry, Ellis Horwood, Chichester, 1990, with permission of Profes.sor D. Pletcher, Department of Chemistry, University of Southampton, Southampton, UK.

Part IV is devoted to electrochemical methods. After an introduction to electrochemistry in Chapter 18, Chapter 19 describes the many uses of electrode potentials. Oxidation/reduction titrations are the subject of Chapter 20, while Chapter 21 presents the use of potentiometric methods to obtain concentrations of molecular and ionic species. Chapter 22 considers the bulk electrolytic methods of electrogravimetry and coulometry, while Chapter 23 discusses voltammetric methods including linear sweep and cyclic voltammetry, anodic stripping voltammetry, and polarography. 

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