Cyclic voltammetry case studies

The anodic oxidation of furans has been studied from both synthetic and theoretical points.285 Because of the many possibilities for delocalization, tetraphenylfuran is a special case but it does allow certain basic processes to be monitored by cyclic voltammetry.286 In nitrobenzene two steps are seen ... 

The simplest and most useful case that one can study by single potential step chronoamperometry is that in which " /2> 0/i (z.e. AEor = E2 - E 5 180 mV). This means that the primarily electrogenerated species Red converts to a new species Ox, which is more easily reducible than the initial species Ox. As seen in Section 1.4.3, in cyclic voltammetry such a system exhibits a single reversible process in the forward scan. 

In principle, the choice of a specific electrochemical technique is not crucial in the study of electrocatalytic processes. However, from a practical and qualitative point of view, cyclic voltammetry is, in most cases, suited for a rapid assessment of an electrocatalytic process triggered by POMs. The interest stems from the following general behavior most POMs undergo a series of reversible one- and two-electron reductions and these reduced forms act usually as the active species, inducing an increase of the corresponding... 

Cu(II) is one of the best examples of a redox active guest, but apparently not when it is imprisoned in a cryptand such as 53. In this case, the Cu(II) is silent over a wide potential range during cyclic voltammetry. System 53 is designed as a lumophore-spacer-receptor system such as 28-30 and 33-34 in Section 1 with multiple lumophores. It also shows similar luminescence off-on switching with and even with Cu(II). The possibility of Cu(II) induced production of from moisture appears to have been ruled out. The absence of EET is a mystery which can only be dispelled by further studies on this interesting system. 

A renewal of interest in the other rate-controlling processes started in those groups who were developing the impedance method [49, 53] and the a.c. polarographic method [12, 25], probably because it was found that, in many cases, Randles equivalent circuit did not hold and also because the appropriate mathematics are more tractable in the frequency domain. Still, it is recommended that the a.c. studies are combined with the diagnostic results which can be obtained from steady-state techniques and/or cyclic voltammetry. 

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