The excitement of nano-test-tube chemistry in a single-walled carbon nanotube is exemplified in our study on electron doping in carbon nanotubes. Electron doping through the 1D van Hove singularity of single-walled carbon nanotubes is realized via a chemical reaction of an encapsulated organocerium compound, CeCp 3 . The decomposition of CeCp 3 inside the carbon nanotubes increases the doping level and greatly enhances the density of conduction electrons. The transition of the cerium encapsulating semiconducting tubes to metallic results in enhanced screening of the photoexcited core hole potential. This fact illustrates the importance of many body effects in understanding core-level excitation process in carbon nanotubes.

The precise atomic structure of activated carbon is unknown, despite its commercial importance. Here we show that the structure of a commercial activated carbon can be imaged directly using aberration corrected transmission electron microscopy. Images are presented both of the as-produced carbon and of the carbon following heat-treatment at 2000°C. In the 2000°C carbon clear evidence is found for the presence of pentagonal rings, suggesting that the carbons have a fullerene-related structure.

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A novel silica-pillared manganese oxide (SiHMnO) was synthesized, and its porous structure was exactly determined by assuming a multistep adsorption mechanism (MSAM) using the low-temperature N2, Ar, and CO adsorption and the αs-comparison plot based on a standard N2 adsorption isotherm on a nonporous manganese oxide. The MSAM method gave a good agreement in values of micropore volume (0.155−0.160 mL g-1) and external surface area (61−63 m2·g-1) from the three adsorbates. The standard nonporous manganese oxide was selected by comparing those based on crystalline hydrous birnessite (H-Bir). The H-Bir-393 obtained by calcining H-Bir at 393 K is the most appropriate standard nonporous material. The values of micropore volume and external surface area from the αs-plot matched very well with those from the MSAM method. SiHMnO has a very high surface area value (483 m2·g-1) by analysis of an αs-plot in contrast to the smaller one (360 m2·g-1) by the ordinary BET analysis.

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