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Abstract: Pyrolysis of a mixture of Fe phthalocyanine and phenolic resin (FePc/PhRs) was studied to clarify the details of the preparation protocol of nitrogen-doped carbon-based materials for cathode catalysts in polymer electrolyte membrane fuel cells. TEM images show that nanoshell carbon is formed by the pyrolysis of FePc/PhRs in the temperature range of 600–800°C. The optimum pyrolysis temperature for the FePc/PhRs mixture was 600°C, where moderate conductivity and high nitrogen content of the prepared carbon were both satisfied. This catalyst showed a promising fuel cell performance with 1.01V open-circuit voltage and 0.33Wcm−2 maximum output, at 0.2MPa absolute pressure and 80°C. A detailed study of the carbonization process suggests that the presence of Fe species during carbonization process contributes to higher nitrogen content and growth of nanoshell structure of the resulting carbon. [Copyright &y& Elsevier]

Abstract: Recently carbon-based catalysts have attracted much attention for its high ability to catalyze oxygen reduction reaction (ORR) in a cathode for polymer electrolyte fuel cells. Among active site models of the catalyst, edge region of sp 2 carbon network is expected to demonstrate high ORR activity comparable to platinum catalysts. However, it is difficult to directly identify the chemical structure of the edge sites by applying conventional structural or electronic probes to actual catalysts. Here, we used C 1s X-ray absorption spectroscopy to observe electronic structure of carbon in iron phthalocyanine-based catalysts, and found a signature of edge exposure below the π* edge, whose intensity is well correlated with the ORR activity. Combined with information about the chemical structure of nitrogen, ORR activity of the catalyst is characterized in terms of the edge exposure. [Copyright &y& Elsevier]

Abstract: ‘Carbon Alloy Catalysts’ (CAC), non-precious metal catalysts for the oxygen reduction reaction (ORR), were prepared from various kinds of nitrogen-containing rigid-rod aromatic polymers, polyimides, polyamides and azoles, by carbonization at 900°C under nitrogen flow. The catalytic activity for ORR was evaluated by the onset potential, which was taken at a current density of −2μAcm−2. Carbonized polymers having high nitrogen content showed higher onset potential. In particular, CACs derived from azole (Az5) had an onset potential of 0.8V, despite being was prepared without any metals. [Copyright &y& Elsevier]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]