Macrodisk electrodes

Explain clearly the reason for the peaked response of linear sweep voltammetric experiments involving a planar macrodisk electrode and a quiescent solution. 

Fig. 20.2. Background cyclic voltammograms in 50 mM sodium nitrate at 100 mV for (1) a gold macrodisk electrode, (2) a 30 NEE (30 electrode NEE), and (3) a 10 NEE. The geometric area for all electrodes was 0.079 cm. (Adapted from Anal. Chem., 1995, 67, 1920).

Fig. 20.4. Cyclic voltammograms at 100 mV s in aqueous TMAFc+ at (I) a gold macrodisk electrode in 50 mM sodium nitrate and (II) a 10 NEE in 1 mM sodium nitrate. TMAFc+ concentrations correspond to (a) 0.5...

Clearly, infrared spectroelectrochemical monitoring is likely to be excellent for electrochemical studies on compounds where intermediates and/or final products exhibit strong infrared bands. Figure 16 illustrates what effectively acts as a very small volume thin-layer cell design in order to achieve very efficient electrolysis at a platinum macrodisk electrode. With this design,... 

Hultgren VM, Mariotti AW A, Bond AM, Wedd AG (2002) Reference potential calibration and voltammetry at macrodisk electrodes of metallocene derivatives in the ionic liquid [bmim] [PFs]. Anal Chem 74(13) 3151-3156. doi 10.1021/ac015729k... 

A Critical Review of the Methods Available for Quantitative Evaluation of Electrode Kinetics at Stationary Macrodisk Electrodes... 

In this chapter, a critical overview is provided of quantitative electrode kinetic studies of fast reactions using the ubiquitous macrodisk electrode under conditions of transient... 

Quantitative Evaiuation of Eiectrode Kinetics at Stationary Macrodisk Electrodes 27... 

Mashkina, E. and Bond, A.M. (2011) Implementation of a statistically supported heuristic approach to alternating current voltammetric harmonic component analysis re-evaluation of the macrodisk glassy carbon electrode kinetics for oxidation of ferrocene in acetonitrile. Analytical Chemistry, 83,1791-1799. 

The first measurement of comparative electrode kinetics between the nano- and macroscales has been recently reported by Campbell and co-workers. The electrode kinetics and mechanism displayed by the nanopartide arrays were found to be quahtatively and quantitatively different from those of a silver macrodisk. As was argued by Campbell and co-workers, the electrochemical behaviour of nanoparticles can differ from that of macroelectrodes for a variety of reasons. The most significant among them is that the size of the diffusion layer and the diffuse double layer at the nanoscale can be similar and hence diffusion and migration are strongly coupled. By comparison of the extracted electrode... 

In reality, very few electrochemical systems fulfill the above criteria, as is danon-strated by the cyclic voltammograms shown in Fig. 5.3a, obtained from the one-electron reduction of [Co(Cp)2] " at a platinum macrodisk electrode in [Cgmirn] [PFg]. Despite the fact that [Co(Cp)2] "" is a well-known reversible process, peak-to-peak separations (AFp) were larger than expected (56.8 mV at 24 C) and increased significantly with scan rate, attributable to the high level of uncompensated resistance 13 kf2) in this highly viscous RTIL [10],... 

Fig. 5.4 Linear-sweep semiintegral voltammograms obtained from the reduction of 10 mM [Co(Cp)2] in [C8mim][PF6] using a 1.6 mm diameter Pt macrodisk electrode with a scan rate of 50 mV s before dashed line) and after solid line) background subtraction. Reprinted with permission from Bentley et ai.. Anal. Chem. 2012,85,2239-2245 [10]. Copyright 2013, American Chemical Society...

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