Microscale electrochemical experiments

Figure 2. Apparatus for microscale electrochemical experiments with [Si(Pc)0]Xy n materials. In the case shown, the equipment is configured for studies in acetonitrile/(Q-Bu)4N+BF4.

In the derivation of Eq. (152), we neglected the quantity of the species produced or consumed at the electrode. In practice this is true for microscale electrochemical experiments but is necessarily inexact for macroscale or exhaustive electrolysis. To derive the general equation, let us consider the total equation for the bulk solution. The chemical contribution is given in Eq. (152). On the other hand, a flux of the species at the convection layer limit (5conv must be considered. This flux corresponds to an algebraic number dNgiec of moles of the species produced, given in Eq. (154),... 

Figure 5. Microscale electrochemical voltage spectroscopy experiments with ([Si(Pc)0](BF4>y)n materials in acetonitrile/ (q-Bu)4N+BF4. Data points were acquired at 50 mV intervals.

Ibanez, J. G. Mayen-Mondragon, R. Moran-Moran, M. T. Alatorre-Ordaz, A. Mattson, B. Eskestrand, S. Laboratory Experiments on the Electrochemical Remediation of the Environment. Part 7 Microscale Production of Ozone, J. Chem. Educ. 2005, 82, 1546-1548. 

Electrochemical synthesis and subsequent isolation of gram or greater amounts of a pure sample of product B, via the electrode process A B + e , requires exhaustive or bulk electrolysis of electroactive material A at a large-size working electrode, although, of course, exhaustive electrolysis of A frequently is achieved on the microscale (mg to pg) level in mechanistic studies at smaller-sized electrodes. Thus, bulk electrolysis can be a useful large-scale synthetic tool and, indeed, is widely used for commercial production of metals such as Cu, Zn, and Al. Bulk electrolysis experiments, when the data are analyzed in a coulometric form, also enable the n value in a voltammetric electrode process to be determined, provided no additional reactions occur on the longer time scale (typically minutes to tens of minutes) associated with such experiments. 

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