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Pt-free cathode catalysts for polymer electrolyte membrane fuel cells have been prepared by multi-step pyrolysis of FePc and PhRs, in the best of which show extensively high initial cell performance and good durability compared to other present precious-metal-free cathode catalysts to date.

A new technique is used to estimate the amplitude of temperature fluctuation in the edge plasma on TST-2. Langmuir probe current-voltage characteristic curves are conditionally reconstituted in terms of the intensity of the floating potential. High/low electron temperatures are obtained in low/high floating potential phases. As a result, normalized temperature fluctuation levels are found to be about 19 % or larger.

The polymer blend technique has been revealed to give a poor yield in the preparation of carbon nanotubes (CNTs) by spinning three-layered core/shell polymer particles having different thermal decomposition properties. In order to elucidate the reason for the low yields obtained by this method, we carried out the present study on employing three-layered core/shell particles, (core) PMMA / PAN-PMAA / PMMA (shell), with electron microscopic techniques. The core/shell structure was not disintegrated by the stabilization and carbonization processes. The influences of the copolymer composition of the carbon precursor polymer (CPP), PAN-PMAA, on the deformation of the core/shell structures were studied. When the concentration of PMAA in the PAN-PMAA copolymer is 3 mol%, the core/shell structure was retained, but when the concentration of PMAA was increased to 7.5 mol%, the core/shell structure disintegrated. By using a copolymer with 4 mol% PMAA, a hollow cigar-like nanostructured carbon was formed; this can be considered to be an indication for the formation of a CNT. Thus, the copolymer composition was found to be an important parameter for the preparation of CNTs by the polymer blend technique. The results obtained in this study indicated the possibility of obtaining CNTs by properly tuning the copolymer composition of the CPP.

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Pyrolysis of iron phthalocyanine/phenolic resin (FePc/PhRs) and phthtalocyanine/phenolic resin (Pc/PhRs) was studied to clarify the effect of Fe during the preparation of carbon alloy cathode catalysts. FePc/PhRs pyrolyzed at 600° showed the best electrocatalytic activity for oxygen reduction. CHN elemental analysis suggests that the catalysts with higher nitrogen content tend to show better catalytic activities. The results of TG/DTA/MS and IR suggest that Fe increases the nitrogen content of the catalysts by enhancing the interaction of phthalocyanine moiety and phenolic resin.

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Carbon and carbon/nickel composite nanorod array electrodes possessing different graphene orientations and crystallinities were synthesized using an anodic aluminium oxide film as a template, and their electrochemical behavior was examined by cyclic voltammetry for the redox reactions of ferri/ferro hexacyanide ions. An attempt was made to examine how the structural differences influence the electrochemical behavior of the arrays and thereby to understand key structural factors affecting their behavior. It was found that the carbon nanorods with the edge planes of graphene sheets exposed to the outer surface were more active than the nanorods covered with the basal planes. Moreover, by using the carbon/nickel nanorod array where each nickel nanorod is covered with a very thin carbon layer, it became possible to evaluate the true electrocatalytic activity of the thin carbon layer. This technique revealed that even a poorly crystallized carbon was intrinsically active, but its high activity was usually concealed from ordinary observation, because of the low electric conductivity.

Iron-containing carbons were prepared from mixtures of ferrocene and poly(furfuryl alcohol) by varying their preparation conditions. The electrocatalytic activity of the carbons was assessed with Fe(CN)63−/Fe(CN)64− redox reaction, and was revealed to be strongly affected by the fraction of a turbostratic carbon structure (Ts-phase) in the material determined by X-ray diffraction.

A new model including the semiconducting phase for the structure of carbons heat treated at lower temperatures is proposed to explain the relation between the electrical conductivity and the infrared (IR) absorption parameter for four carbonized polymers. The latter parameter was obtained by analyzing the absorption edge in the IR region. The conductivity was semiquantitatively simulated using effective medium theory coupled with percolation theory. Alternatively, an extension of effective medium theory to a three‐phase model proposed here is able to simulate the conductivity.

The carbonization process of type C mesocarbon microbeads was studied using X-ray diffraction (XD), XPS and FT-IR. The intensity of absorption continued from the visible to the IR region observed by FT-IR spectroscopy and increased with the heat treatment. A theory of amorphous semiconductors was applied to simulate the absorption edge, and it was found that a factor relating to the absorption A correlated well with the diameter of graphite-like crystallite (La) obtained from XD for the specimens heat-treated above 700°C. Also, A was found to have good correlation with a valence band peak in XPS spectra, and this was interpreted by the increase in the density of electronic states, which could be excited by the infrared ray.

Symmetrical and unsymmetrical (E,E)-1,4-diaryl-1,3-butadienes can be prepared in high yields from (E)-2-arylethenesulfonyl chlorides by treating with vinylarenes in the presence of ruthenium(II) phosphine complex in benzene.

La reaction des chlorures de styrenesulfonyle, propene-1 sulfonyle et d'ethylenesulfonyle avec des derives du styrene, conduit a des diaryl-1,4 butadienes-1,3 via des (alcene-1yl [aryl-2 chloro-2] ethyl) sulfones

Symmetrical and unsymmetrical (E,E)-1,4-diaryl-1,3-butadienes can be prepared in high yields from (E)-2-arylethenesulfonyl chlorides by treating with vinylarenes in the presence of ruthenium(II) phosphine complex in benzene.