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A nitrogen-containing microporous carbon with a highly ordered structure was synthesized by using zeolite Y as a template. The filling of carbon into zeolite channels was performed by the impregnation of furfuryl alcohol and subsequent chemical vapor deposition (CVD) of acetonitrile. The template was then removed by HF washing. The two-step carbon filling process (the impregnation and the CVD) was found to be essential for obtaining both high microporosity and ordering. This carbon is characterized by its very large surface area (3310 m²/g) and very narrow micropore size distribution (1.0−1.5 nm), and it contains nitrogen of 6 wt %, most of which is quaternary nitrogen. The distribution of nitrogen atoms in the carbon was examined by the detailed analysis of the carbon deposit at each carbon-filling step. The effect of nitrogen doping on the affinity to H2O molecules was elucidated from the comparison of the H2O adsorption behavior between this carbon and a nitrogen-free ordered porous carbon with a very similar pore structure. It was found that the nitrogen-containing carbon has a higher affinity to H2O molecules than the nitrogen-free carbon.

The detailed synthesis of highly hydrophobic average pore benzene-bridged hybrid mesoporous silicas under an acidic medium is described. With the use of a 1,4-bis(triethoxysilane)benzene silsesquioxane precursor and biodegradable alkyl polyoxyethylene (Brij-56 or Brij-76) nonionic surfactant oligomers as supramolecular templates, no molecular scale periodicity was observed. The well-defined mesoporous materials could be synthesized with two-dimensional hexagonal (p6mm) symmetries. The textural and surface properties (adsorption isotherms of water and benzene vapors) were estimated and were compared to the analogous benzene-bridged mesoporous silica with molecular scale periodicity which was prepared using cationic surfactant under basic conditions. Different textural properties resulted for the two kinds of materials and revealed some important insights regarding the structure and nature of the materials.

The magnetic susceptibility χ of O2 adsorbed in micropores of activated carbon fibers (ACFs) having different micropore widths was measured at a wide temperature range of 1.7−100 K. The micropore structure of ACF was determined by the analysis of the N2 adsorption isotherm at 77 K. The adsorption isotherm of O2 on ACF at 77 K was determined and it was shown that O2 is adsorbed in the micropore in a similar way to N2 from the Dubinin−Radushkevich analysis of O2 and N2 adsorption isotherms. The χ−T relation suggested the presence of three kinds of O2 molecular states in the micropore, that is, the isolated, the cluster, and condensed states; their stable region changes with the fractional filling and the temperature. Although the potential energy difference of the O2−surface interaction of different pore systems is only 150 K by the potential calculation, the magnetic susceptibility measurement can sufficiently evidence distinctly the presence of different states of O2 molecules in the micropore.

Defective state of C60 crystals was controlled by the recrystallization and annealing. The defective structure was examined by the X-ray diffraction and N2 adsorption at 77 K. Recrystallized C60 crystals without annealing showed broad diffraction peaks and the N2 adsorption isotherm had marked low pressure uptake and a hysteresis in the high pressure region, indicating presence of both micropores and mesopores. The average micropore width was 8 Å which is closed to the C60 molecular size, while the average mesopore one was 50 Å. The mesopores disappeared by annealing up to 393 K. On the other hand micropores of 8 Å remained even by heating up to 673 K.