Four methods were examined to prepare porous carbons with controlled micropores from phenolic resins. Firstmethod carbonizes phenolic resins synthesized from formaldehyde and various phenols. At the carbonization temperatureof 600°C, phenol-resin or 1, 2, 3-trihydroxybenzene-resin had uniform micropores of 0.4 to 0.45nm in diameter, whereas 1, 5-dihydroxynaphthalene-resin had larger micropores of 0.4 to 0.5nm in diameter. The larger pores werefound to be formed through the devolatilization of 1, 5-dihydroxynaphthalene remaining in the resin. This presenteda possibility to control micropores by devolatilizing the substance incorporated in the resin during carbonization.
Second method carbonizes resins prepared from the mixture of two different phenols. The mixed resin synthesizedfrom 1, 2, 3-trihydroxybenzene and 1, 5-dihydroxynaphthalene had large micropores of 0.9 to 1.1nm which did notexist in either 1, 2, 3-trihydroxybenzene or 1, 5-dihydroxynaphthalene-resin. This presented a possibility to controlmicropores by carbonizing mixed resins.
Third method uses resin of different cross-link densities as starting materials. However, the cross-link densitydid not affect significantly the size of micropores of carbonized resins.
Fourth method is to control the carbonization by loading mechanical pressure, and consequently to controlmicropores of carbonized resins. This method was found to be effective to decrease the size of micropores.

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Carbon thin films on the surface of quartz substrates were prepared by the thermal decomposition of organiccompounds with low molecular weight, such as benzene, cyclohexane, tetrahydrofuran and pyridine. The structure andelectrical properties of the films obtained were studied. From SEM observations, it was found that the thickness of thecarbon films increased with the increase of the deposition time. The homogeneous films without any cracks and withoutany peeling off from the substrates were obtained with a thickness less than 1 μm. By the XRD measurements of the filmson the substrate, it was clarified that the graphitization degree of these films had very low. In order to examine thechemical bonding state in the carbon films, X-ray photoelectron spectroscopy was carried out in all films obtained. Inthe case of the film prepared from pridine, the nitrogen existed as a tertiary bonding state, replacing carbon atoms inhexagonal layers. The electrical conductivity of the film obtained from cyclohexane showed the high value of 2.5 × 10⁵S/m, but that of the film prepared from benzene gave a small value of 0.3 × 10⁵ S/m. Hall coefficient was found to showextremely small values at room temperature in all films obtained, ranging from 2.3 × 10^-9 to-2.4 × 10^-9 m³/C.

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Intercalation behaviors of alkali metals into natural graphite flakes in the solutions of dimethoxymethane (DMM) and diethoxymethene (DEM) containing alkali metals have been investigated bymeans of X-ray diffraction.Ternary graphite intercalation compounds (GICs) containing lithium were obtained from the solutions of Li-DMMand Li-DEM. On the other hand, binary GICs were prepared from those solutions for K, Rb and Cs. Sodium did notdissolve into the solvents.

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Boron-substituted disordered carbons indicate large Li storage compared to pristine carbons and can be apromising anode-material in high-energy Li-ion batteries. In order to clarify the reason why boron-substituted carbonscan store more Li atoms than pristine carbons, we employed polyaromatic hydrocarbons as model clusters for disordered carbons and investigated the effect of boron and nitrogen substitutions on the stable structures and electronic propertiesof model clusters, by using a semiempirical molecular orbital method. By boron-substitution into carbon clusters, anelectron acceptor level is created in a lower energy region than that for the pristine carbon cluster. This lower levelaccepts electrons from the absorbed Li atoms more easily, so that the stabilization energy by Li absorption for the boronsubstituted cluster is much larger than that for the pristine carbon cluster. Onthe other hand, for the nitrogen-substitutedclusters, the electron acceptor level is almost the same as that for the pristine carbon, so that the stabilization energyis not enhanced by nitrogen-substitution. Therefore, we conclude that the large Li storage in boron-substituted disorderedcarbons is related to the creation of a lower electron-acceptor level caused by boron-substitution, which makes easierelectron transfer from absorbed Li atoms to host materials.

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The BET surface area of porous carbonaceous materials obtained by chlorine treatment after devolatilizationof phenolic resin at relatively low temperature 600°C, successive heat treatment and dechlorine treatment, ranged 910to 1080m²/g. When the porous carbonaceous material thus prepared was used as an electric double layer capacitor carbonelectrode, the capacitor exhibited a large electrostatic capacity (about 110mF/m²) The electrostatic capacity of moldedsample was about 30F/cm³ even at a high current density of 500mA/cm². Therefore chlorine treatment is effective forthe preparation of carbonaceous materials for electric double layer capacitor which is suitable to a high-powersupplementary power source.

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Charcoals were prepared from Japanese cypress (C. obtusa) and Japanese oak (Q. mongolica) by threecarbonization methods, (a) in a nitrogen stream, (b) in an air stream, (c) in a container with cover. The relationshipbetween the carbonization methods and the adsorption properties of the charcoals was investigated and the followingresults were obtained.
Regardless of the carbonization method or the kind of wood used, the surface of charcoals prepared at lowtemperature was acidic and that of charcoals prepared at high temperature basic. The surface of charcoals preparedby method (c) showed the highest acidity.
When benzene, iodine and phenol were adsorbed for short periods onto charcoals prepared by methods (a) and (c), the charcoal prepared at 600°C had the largest mean pore size, and also showed the fastest adsorption rate and thehighest adsorption capacity. Of the charcoals prepared by method (b), the charcoal prepared at 900°C had the highestadsorption capacity. The charcoal prepared at 1000°C showed a decrease in adsorption capacity because of thermalshrinkage of the pores.
For all methods, adsorption capacity for water vapor was lowest in the charcoal prepared at 600°C. However, the amount of water vapor desorbed when humidity decreased was highest in the charcoal prepared at 600°C It was found that the 600°C charcoal is the best for use in humidity-control.

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Kneading process is an important process in manufacturing lubricating carbon blocks, because a failure occurred during the temperature controlling process sometime gives high friction coefficient to the blocks. Effects of boric acid (H3BO3) addition on reducing the friction coefficient were examined by two introduction methods. A method was toimpregnate the carbonized carbon block with boric acid followed by another heat treatment at 2800°C, which was theproduct with over permissible limit of friction coefficients for the markets (μ<0.3). The impregnation with boric acidgave an improvement in reducing the coefficient with remaining the apparent density and the bending strength constant. Another method was to mix raw materials for the blocks with boric acid followed bycarbonization and graphitization. Addition of 1 wt% of B in the form of boric acid gave a carbon block with a set ofsimilar properties to the marketableproducts, though the kneading temperature employed was as high as the temperature giving failed products for the usualmixture of raw materials. Consequently, addition of boric acid to the raw materials was proved to be an useful foolproofmethod for saving a control in the kneading temperature.

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Intercalation of Li into graphite was performed by a chemical method in various ether-type solvents oftetrahydrofuran (THF), 2-methyl tetrahydrofuran (2-MeTHF), 2, 5-dimethyl tetrahydrofuran (2, 5-diMeTHF), 1, 2-dimethoxyethane (DME), 1, 2-diethoxyethane (DEE), 1, 2-dibutoxyethane (DBE), 1, 2-dimethoxymethane (DMM), 1, 2-diethoxymethane (DEM), 1-methoxypropane (MP), 1-methoxy-butane (MB), diethyl ether (Et₂O) and resultant products were studied by X-ray diffraction. For the solvents of THF, DME, DEE, DBE, DMM, DEM, ternary Li-solvent-graphite intercalation compounds (GIC) were obtained. On the contrary, for the other solvents, only Li intercalated into graphite to form binary Li-GIC. The criteria for the solvent co-intercalation were discussedin terms of the electron donicity of the solvents, the size of the solvents and also the size of Li-solvent complexes.

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Titanium oxide catalysts were prepared on activated carbon fibers (ACF) using an ionized cluster beam (ICB) method and their photocatalytic reactivity for the degradation of organic compounds diluted in water was investigated.Utilization of the ICB method under oxygen atmosphere enables to prepare the titanium oxide photocatalysts onto ACFat relatively low temperatures without causing any damages of ACF support. Characterizations of these catalysts bymeans of SEM, EXAFS and XRD techniques showed that titanium oxide particles are formed on ACF in an anatasestructure. UV irradiation of these catalysts in the diluted aqueous solution of 2-propanol led to the formation of acetoneand CO₂, indicating that the titanium oxide particles on ACF exhibit an efficient photocatalytic reactivity. Thus, thepresent results have clearly demonstrated that the ICB method is useful in the development of combination system ofthe titanium oxide photocatalysts with an activated carbon without calcination treatment at high temperatures.

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Pd- and Pt-metal were observed by TEM to be highly dispersed on charcoal prepared from Japanese Cypress “Hinoki” at 900°C (Pd, Pt/H2). Nafion-sheet was hot-pressed with Pd/H2 and Pt/H2 disc-pellets placed in the othersides to make a fuel cell-electrode unit. The I-V curves in the H₂-O₂ fuel cell were measured: The voltage certainlygrew with increase in the amount of Pd-metal (1→12wt%) and with a mixing of “Nafion” powder (11 wt%). Thedischarge character was greatly improved with the addition of heteropolyacid (H₃PMo₁₁ VO₄₂; PVMo₁₁). When acharcoal prepared from Hinoki at 2400°C (HG) was used, the inner resistivity was about 10-times lower than the caseof H2 used, although the dispersed states of Pd-metal became considerably poor on HG rather than H2.The activityalso increased further with the addition of Nafion and PVMo₁₁

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Carbonaceous mesophase spherules (MS), prepared from coal-tar pitch, have a layer structure exposing the edgesof constituent aromatic molecules to the surface. Oxidation with nitric acid converted MS from hydrophobic to hydrophilicnature due to introduction of acidic functional groups to the surface. A water thin layer was formed on MS surface bysuspending oxidized MS in water followed by in benzene, i.e., W/O emulsion was formed. Na₂O·nSiO₂(n: 2.18-3.14) dissolved in the water layer was allowed to react with (NH₄) ₂SO₄ to coat MS surface with silica. Detailed reaction conditions were clarified to successfully coat MS by silica. Silica-coated MS showed high BET surface area (as much as 200 times) compared with oxidized MS.

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Electrochemical behavior of semiconducting diamond thin-film electrodes has been studied by measuring cyclicvoltammograms for the anodic oxidation of 1, 4-difluorobenzene in the electrolyte, neat Et₄NF·4HF. A comparativestudy using a Pt-electrode establishes that the electrochemical fluorination of 1, 4-difluorobenzene using the diamondelectrode yields 3, 3, 6, 6-tetrafluoro-1, 4-cyclohexadiene. Furthermore no peaks corresponding to the redox reactionof Pt-electrode, i.e., the formation and reduction of PtO₂, are observed in the CVs obtained using the diamond electrode, suggesting that the diamond electrode is more stable than the Pt-electrode. The results suggests that electrochemical fluorination and the electrolytic production of elemental fluorine are possible at the dimensionally stable diamond electrode.

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Electronic structures of carbon fragments somewhat differs from that of ideal graphite due to existence of edgeor “surface”, which are of importance in consideration of the electronic properties and/or chemical reactivities etc. forthese finite systems. In this summary a broad outlook of such researches covering analyses of this kind of electronicstructures is introduced. One of the most important factors would be the “shape” of the surface.

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Physical adsorption of gases has been revised in terms of the Theory of Micropore Filling as a technique tocharacterise microporous carbons (carbon fiber, carbon molecular sieve, activated carbon and char). Special attention has been paid to the CO₂ adsorption isotherms at 273K, obtained using subatmospheric and high pressures. Becausethe relative pressure range covered by our CO₂ study is similar to the one covered with N₂ at 77K, a suitable comparisonof both adsorptives has been possible. Thus, we have been able to demonstrate that CO₂ is an adsorptive that behavesat 273K similarly to the well-accepted N₂ at 77K. In addition, the results show that the narrow microporous carbonsshould not be characterised only by N2 at 77K, otherwise the results can be useless. We encourage the use of CO₂ (i.e.at 273K) as a complement to N₂ adsorption. This suggestion is especially relevant considering that the most frequentavailable adsorption equipments use only N₂ at 77K and that most of the researchers limit the characterisation ofmicroporous carbons to this adsorptive.

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