Nature of the Surface Compounds and Reactions Observed on Graphite Electrodes

The nature and composition of the surface of pyrolytic graphite and the consequent possible effects, when the material is used as an electrode. are considered on the basis of the structure of the graphite and of the handling and/or treatment to which the electrodes may have been exposed. Because of the relatively limited studies on pyrolytic graphite, certain aspects of the behavior of other types of graphite and of carbon are discussed owing to their probable relation to the behavior of pyrolytic graphite. An appreciation of the constitution of graphite electrodes in terms of surface compounds and of the possible interaction of these compounds with solution species or their reaction products, when the electrodes are used in electrolytic processes, is essential for their optimum utilzation. The main areas surveyed are the structure of pyrolytic graphite as related to electrode usage, types of possible compound formation, electrolytic behavior of graphite electrodes, and formation of carbonoxygen and related organic surface compounds with the resulting influence on adsorption and other