An impermeable carbon electrode was developed as a new electrochemical detector. The electrode made of graphite/glassy carbon composite (30/70 weight ratio) was prepared by the Plastic Formed Carbon (PFC) method. The microstructure of the surface of the PFC electrode was observed by scanning electron microscopy. The impermeability and the electrochemical behavior of the electrode, in comparison with HOPG, were evaluated by cyclic voltammetry in solution of 18 M sulfuric acid. The SEM observation and the cyclic voltammetry suggest that the disk plane and the cylindrical plane of PFC electrode have similar microstructure and similar pattern of cyclic voltammograms of ferro-/ferri-cyanide ions in solution of potassium chloride to those of the edge plane and the basal plane of the HOPG, respectively. The potential window on the PFC electrode was + 1.6V to -1.3V in 1 M sulfuric acid solution (vs. SCE), and this potential range corresponds to that on a glassy carbon electrode. A peak current in a redox reaction of ferrocyanide and ferricyanide was proportional to the concentration of ferrocyanide and ferricyanide ions. No change was observed in the pattern of the cyclic voltammogram of ferro-/ferri-cyanide ion response in potassium chloride solution on the PFC electrode after 100 -day immersion of the electrode. The PFC electrode showed a stable response of the surface reaction, and the reproducibility was good. Although the anode peak, which corresponds to the formation of the first-stage graphite intercalation compound, was found in the CV curves, repeated-cycle experiment indicated that the surface of the PFC electrode was almost as impermeable as glassy carbon.

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Mesophase pitch-based carbon fibers (CF) with high strength have been studied by scanning electron microscopy and other technique, It has been suggested that there is strong correlation between folded structure of fibril in transversal cross-section of the fiber and the tensile strength. In the present paper, we tried to characerize the cross-section morphology of the mesophase CF using a computer image processing combined with high resolution field emission scanning electron microscopy (FE-SEM). The process of smoothing, getting binary image, noise reduction and thinning were carried out on the FE-SEM pictures . Then fractal dimension of the fibril was calculated to determine the numerical characteristic of the CF. The method was applied to four kinds of samples of the mesophase pitch-based CF, and the samples were compared with one another in connection with tensile strength and fractal dimensions of each samples were closely related to the tensile strengths. The texture of fibril in the cross-section of the fibers can be characterized quantitatively by image analysis combined with FE-SEM.

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Stage 2 FeCl₃-graphite intercalation compound (GIC) was chemically reduced with lithium-naphthalene complex in THF and 1-MB. The GIC was also reduced electrochemically in THF, PC and EC+DEC, containing 1 mol/dm³ of LiClO₄. When the reduction was performed in THF chemically or electrochemically, fine iron particles were obtained in the graphite matrix. The mean diameter of the particles is in the range of 11-13nm in this case, while 4nm for 1-MB. For PC and EC+DEC, no iron particle was observed in the product. The difference would be related to the co-intercalation of the solvent. In the reduction process, THF is incorporated together with lithium in the interlayer spacing of FeCl₃-GIC. The co-intercalated THF molecules facilitate the reduction of FeCl₃ by lithium in the graphite gallery probably because FeCl₃ is soluble in THF, and relatively large iron particles are obtained.

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Formation and graphitization of vapor-grown carbon fibers were reviewed. Fundamental conditions for the formation of fibers were discussed on two methods; seeding and floating catalyst methods. The graphitization behavior of the fibers prepared by these two methods was also discussed in relation to fiber diameter.

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