Azobenzene and p-aminoazobenzene molecules were introduced into nano-space of various surfactant-intercalated graphite oxides via self-assembly. The composition of surfactantintercalated graphite oxides saturated by azobenzene molecules were determined from their X-ray diffraction data. The azobenzene contents increased with the increase of alkyl chain length of surfactants, while they were almost independent of surfactant contents in the intercalation compounds. Azobenzene molecules were dispersed in the nanospace of surfactantintercalated graphite oxide without crystalization. On the other hand, blue shift of absorption peak due to p-aminoazobenzene molecules suggested that they formed H-aggregate when their concentration was high.

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Porous carbons were prepared by carbonization of phenol resins of different novolac/resol ratio. By mixing 20wt % of resol with novolac (Carbon samples Ph-C2 and Ph-C3), BET and mesopore surface areas remarkably increased. The addition of more than 50wt% of resol (Carbon samples Ph-C4 and Ph C-5) deceased BET specific surface area and scarcely accelerated the formation of mesopore. The adsorption of acid dye (Acid Blue 9), basic dye (Basic Brown 1), direct dye (Direct Yellow 11) and metal ions, Cr (VI), Pb (II), and Zn (II) were investigated. The adsorbed amounts of Basic Brown 1 and Cr (VI) on Ph-C2 are higher than those on Ph-C4 and Ph-C5. Direct Yellow 11 of large molecule in size highly adsorbed on Ph-C2 and Ph-C3 of high mesopore content.

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The hydrogen adsorption isotherms of activated carbon fiber (ACF), single-walled carbon nanotube (SWCNT) and H-Y-type zeolite (H-YZ) were measured at 77 and 303K in a hydrogen pressure of 0-3.5MPa. The amount of adsorbed hydrogen by weight depended on the micropore volume of the samples. The ACF with the greatest micropore volume indicated the maximal amount of adsorbed hydrogen. The amount in SWCNT was remarkably increased by the treatment in 4N HNO₃. Further, the hydrogen adsorption behavior of ACF and H-YZ loaded with platinum and palladium (M-ACF and M-YZ) was investigated at 303K in 0-5MPa. The increase in the amount of hydrogen adsorbed on M-ACF and M-YZ was observed in the range of 0-0.01MPa by the chemisorption of hydrogen on platinum and palladium. However, the metal loading did not enhance the physical adsorption capacity of ACF and YZ at higher pressures up to 3MPa.

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We propose that addition of hydrogen atoms at zigzag edges of nanographite and nanotubes may be a way to produce magnetic nanographite and magnetic nanotubes. When a carbon atom at the zigzag edge is terminated by two hydrogen atoms, the zigzag edge of the n-electron network is modified and behaves like the Klein edge. Thus difference in numbers between starred carbons and unstarred ones appears in nanographite and in a nanotube with a normal zigzag edge and a zigzag edge made of di-hydrogenated carbons. Our first-principles band-structure calculation of graphene ribbon prepared by this method shows existence of a spin-polarized flat band at the Fermi level. The result coincides with a conclusion of the Hubbard model on the graphene ribbon, where the Lieb theorem predicted existence of ferrimagnetism.

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Boron doping to carbon nanotube was carried out on pressed samples of multiwall carbon nanotube (MWCNT) prepared by a CVD method. As-prepared sample was pressed as disks of 20mm in diameter with an apparent density of 0.72g·cm³. The disks were heat-treated at 3000°C to remove iron impurity. From the heat-treated disks, samples with sizes about 1.5×1.5×6mm³ were cut. Boron doping was carried out by heating the sample to 2300°C in a crucible made of a commercially available artificial graphite contained 10wt% born. We employed lhr heat treatment as a unit of doping treatment, and carried out doing of 1 to 3 times for the samples. Boron concentrations of the boron-doped samples were determined by an EPMA technique. Structural characterization of the doped samples was made with X-ray diffraction and Raman spectroscopy measurements and SEM observation. The characterization revealed that almost of born doped samples were consisted of MWCNT's contained boron, small thin boron-contained crystallites with graphite structure and B₄C small crystals. Effect of boron doping was examined by the measurements of electrical resistivity at liquid nitrogen and room temperatures and magnetic susceptibility at 5 and 300K as a function of boron concentration for the boron-doped samples.

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A high value of discharge capacity for the negative electrode of Li ion secondary battery, 554mAh/g at second cycle, was obtained using a polyparaphenylene (PPP)-based carbon material heat-treated at 720°C. The PPP is a kind of low crystalline carbon material. Li ion charge and discharge capacities of low crystalline carbon are thought to depend strongly on the resistance and the microstructure of the material. In order to clarify the effect of heat-treatment on the characteristics of PPP-based carbon as a negative electrode in the temperature range from 680 to 900°C, electrical and structural characteristics were investigated by means of charge-discharge capacity and resistivity measurement, field emission scanning electron microscopy and high resolution transmission electron microscopy and image analysis.

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LiMn₂O₄ with fluorine-carbon nanocomposite surface was prepared by carbon coating with an arc discharge (nCLiMn₂O₄, n=number of times of arc discharge for 0.1s) and by fluorination using NF₃. Potentiostatic charge behavior of surface modified LiMn₂O₄ at 4.3V revealed that the nano-thickness carbon coating made after surface fluorination prevented the electrolyte solution from the oxidative degradation on the LiMn₂O₄ during charge process. From charge/discharge cycle test (50 cycles) at a constant current corresponding to the rate of 0.3C, 30CLiMn₂O₄ obtained after surface fluorination with NF₃ exhibits the smallest decrease in discharge capacity through 50 cycles and the largest discharge capacity at 50^th cycle among the samples examined in this study.

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Thermal decomposition of C₆₀ was studied by x-ray diffraction and time-of-flight mass spectroscopy, which was carried out in a high-purity argon gas for 3h at the temperature ranging from 500 to 1000°C. The diffraction peaks corresponding to C₆₀ of cubic system were detected in the samples heated below 500°C. With the increase of temperature, these peaks of C₆₀ were broadened, and the diffraction peaks corresponding to chaoite of hexagonal system were detected. From time-of-flight spectroscopy, it was found that two molecules of C₂₂ and C₄₈ were produced by heating C₆₀ at 600°C, though not resolved C₆₀ remained. The decomposition of C₆₀ advanced with the increase of temperature. At 1000°C, it was found that C₆₀ was decomposed into five molecules, such as C₉, C₂₂, C₂₅, C₃₅ and C₄₈.

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Lithium acetylide (LiC=CLi) was easily oxidized by exposure in CO₂ at room temperature, resulting in reaction product mixture composed of carbon and lithium compounds (mainly Li₂CO₃). Porous carbons containing mesopores and macropores were prepared by removal of the lithium compounds using immersion in hydrochloric acid. The pore formation was derived from micro-domain structure consisting of the carbon matrix and the lithium compounds in the lithium acetylide oxidized with CO₂. Furthermore, the macropores and mesopores in the porous carbon were developed by the heat treatment (1000°C) of the oxidized lithium acetylide before the acid immersion.

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Development of carbon materials was divided into three periods; down to 1960 classic carbons were mostly studied and produced, in 1960-1985 various new carbon materials were developed and from 1985 to now fullerenes and carbon nanotubes attracted attentions. Features of each period were discussed. Different classifications of carbon materials, such as graphitizing and non-graphitizing carbons, classic and new carbons, etc., were also summarized. Based on these discussions, it was proposed that a novel classification of carbon materials, that is, nanocarbons, has to consist of not only nano-sized materials, such as fullerenes and carbon nanotubes, but also nano-structured materials, such as well-controlled porous carbons and boron-doped carbons.

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Carbon nanotubes and nano-graphite are called as nano-carbons made of graphene skeleton. Resonant Raman spectroscopy is a powerful tool to investigate the special electronic and phonon structures of nano-carbons. Although Raman spectroscopy has been used for characterizing carbon materials for long years, the origin of some weak Raman spectra is not always clearly understood. The recent progress of Raman spectroscopy has provided a new concept such as double resonance Raman theory for the undefined spectra observed not only in nano-carbon but also in conventional carbon materials. Especially single nanotube spectroscopy becomes a standard technique in which we measure with no-contact, at room-temperature and ambient pressure.

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