Pyrolytic graphite electrode surfaces

A.M. Oliveira Brett and A.-M. Chiorcea, Atomic force microscopy of DNA immobilized onto a highly oriented pyrolytic graphite electrode surface, Langmuir, 19 (2003) 3830-3839. 

Figure 2. Low-resolution XPS spectra of a pyrolytic graphite electrode surface. Key A, prior to modification B, following a l-h 02 rf plasma treatment C, after reduction with LiAlHi D, after modification with cyanuric chloride E, after attachment of hydroxymethyl ferrocene and F, following electrolysis in pH 7 phosphate buffer.

Zagal, J. Sen, R.K., and Yeager, E. (1977). Oxygen reduction by Co(Il) tetrasul-fonatephthalocyanine irreversibly adsorbed on a stress-annealed pyrolytic graphite electrode surface./ Electroanal. Chem., 83, 207—13. 

Evans, J. F., and Kuwana, T., 1977, Radiofrequency oxygen plasma treatment of pyrolytic graphite electrode surfaces. Anal. Chem. 49 1632-1635. 

Zagal J, Sen RK, Yeager E. Oxygen reduction by Co(ll) tetrasulfonatephthalocyanine irreversibly adsorbed on a stress anneled pyrolytic graphite electrode surface. J Electroanal Chem 1977 83 207-13. 

FIG. 16 Current versus bias voltage for a CdS nanoparticle on the end of an STM tip. The CdS particles were formed by exposing a bilayer of cadmium arachidate on the STM tip to H2S gas. The other conducting surface is a highly oriented pyrolytic graphite electrode. The inset is a plot of differential conductance versus the bias voltage. (Reproduced with permission from Ref. 202. Copyright 1996 National Academy of Sciences, U. S. A.)... 

It has been recently demonstrated that the simplest of the cobalt porphyrins (Co porphine) adsorbed on a pyrolytic graphite electrode is also an efficient electrocatalyst for reduction of 02 into 1120.376 The catalytic activity was attributed to the spontaneous aggregation of the complex on the electrode surface to produce a structure in which the cobalt-cobalt separation is small enough to bridge and activate 02 molecules. The stability of the catalyst is quite poor and largely improved by using porphyrin rings with mew-substitu-tion.377-380 Flowever, as the size of the mew-substituents increases the four-electron reduction efficiency decreases. 

Fig. 4.2 Scheme of a part of the three-phase electrode consisting of pyrolytic graphite electrode modified with an uneven thin film of an organic solvent covering partly the electrode surface and containing a neutral redox probe... 

This method involves electrochemical deposition of the MPc onto CNT-modified electrode surface by repetitive cycling in a concentrated MPc solution (1 mM) within a specific potential window. The first cyclic voltammetric scan is usually similar to subsequent scans, indicating the formation of monomeric species only. Ozoemena et al [11] found that on certain occasions, as reported recently [11] during the electro-deposition of CoTAPc onto a basal plane pyrolytic graphite electrode (BPPGE) pre-modified with SWCNT, both cathodic and anodic waves may decrease continually and then stabilizes at a certain scan (a process known as electrochemical adsorption or simply called electrosorption ). 

Kano K, Uno B (1993) Surface-redox reaction mechanism of quinones adsorbed on basal-plane pyrolytic graphite electrodes. Anal Chem 58 2009-2012. 

This technique has been applied to the study of the reduction of the Keggin heteropolyanion [PM012O40]3- immobilized at the surface of a BDD electrode in aqueous media with two electrolytes HCIO4 1.0 M and LiC104 0.1 M. In the case of carbon electrodes like Glassy Carbon or Pyrolytic Graphite electrodes, in aqueous acidic media, three reversible waves are observed in the potential range (0.6, 0.2)... 

Fig. 11.22. Example structures for monolayer covalent bonding to edge plane pyrolytic graphite electrodes. (Reprinted from Techniques of Chemistry, Molecular Design of Electrode Surfaces, R. W. Murray, ed., Vol. 22, p. 143. Copyright 1992 John Wiley Sons. Reprinted by permission of John Wiley Sons, Inc.)...

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