Carbon electrodes pyrolitic graphite

Figure 22 Cyclic voltammograms recorded in aqueous solutions of Rieske fragments from (a) bci complex glassy carbon working electrode pH 7.2 (b) (recombinant) biphenyldioxygenase (basal) pyrolitic graphite working electrode (in the presence of the positively charged additive neomycin) pH 7.0. Scan rate 0.01 V s ...

Since rusticyanin is positively charged (p/=9.1), its electrochemical response should be tested at negatively charged electrodes (namely, edge-plane pyrolitic graphite or glassy carbon electrodes). As a matter of fact, no positive response is obtained at a carbon paste electrode, but in the presence of a promoter such as 4,4/-bipyridyl a sufficiently resolved cyclic voltammetric response is obtained, Figure 37.67... 

Concerning the substrate, practically any material can be used to form a modified electrode, although the most used are gold, silver, platinum, mercury, and carbon (in its different variants, like glassy carbon, Highly Oriented Pyrolitic Graphite (HOPG), or Boron-Doped Diamond (BDD) electrodes [39]). 

FIGURE 7.15 CVs for4-chloro-2-nitrophenyl-derivatized carbon powder immobilized on basal plane pyrolitic graphite electrode in contact with 0.10 M HCl aqueous solution. The potential scan rate, 50 mV/sec. 

Moore, R.R., Banks, C.E., and Compton, R.G. (2004) Basal plane pyrolitic graphite modified electrodes comparison of carbon nanotubes and graphite powder as electrocatalysts. Arud. Chem., 76 (10), 2677 — 2682. 

At carbon electrodes, which are widely used in electrochemistry, the double layer develops too however, these electrodes have some specific interfacial properties. The two main types of carbon electrodes glassy carbon and highly oriented pyrolitic graphite (HOPG) and the recently introduced boron-doped diamond, differ much in the bulk and the surface structure. They also differ in electrochemical activity. Particularly large differences exist for the two surfaces of... 

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