The synthesis and application aspects of ordered mesoporous carbon (OMC) as a novel material for fuel cell catalysts are reviewed in this paper. The synthesis and structural characterization of OMC is outlined and the recent advances in the synthesis of OMC relevant to fuel cell technologies is presented. Recent examples of the application of OMC as a support for fuel cell catalysts are summarized and practical approaches for the application of OMC for the fuel cell systems are discussed. Future perspectives on the use of OMC in energy conversion and storage devices are also suggested.

Highly ordered cobalt substituted MCM-41 samples were synthesized and characterized for application as catalytic templates for producing aligned single walled carbon nanotubes (SWNT). Highly reproducible Co-MCM-41 samples were successfully synthesized using alkyl templates with 10, 12, 14, 16, and 18 carbon chain lengths by direct incorporation of cobalt into the siliceous MCM-41 framework using a hydrothermal method; the pore size and the pore volume can be controlled precisely. The local environment of cobalt as determined by UV-vis spectroscopy is a mixture of tetrahedral and distorted tetrahedral structures similar to those observed in Co 3 O 4 . Cobalt atoms are uniformly distributed in the pores (about 30-40/pore) at nearly atomic dispersion probed by XAFS. Incorporation of cobalt into siliceous MCM-41 improves the structure, most likely by dehydroxylation and/or knitting the defective structure of the amorphous silica polymer. The optimum crystallization temperature and time were 100 °C and 4 days for siliceous MCM-41 and 6 days for Co-MCM-41, respectively. Co-MCM-41 is very stable against reducing and oxidation conditions at temperatures under 750 °C. The catalytic templates showed over 90% selectivity to SWNT with up to 4 wt % carbon yield. The growth of SWNT in the pores of Co-MCM-41 was confirmed by Raman spectroscopy and TEM. The catalytic template maintained its structure after successive reaction cycles, which suggests that Co-MCM-41 is a very stable template for producing SWNT under harsh reaction conditions.

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Developing electrode materials with high-energy densities is important for the development of lithium-ion batteries. Here, we demonstrate a mesoporous molybdenum dioxide material with abnormal lithium-storage sites, which exhibits a discharge capacity of 1,814 mAh g−1 for the first cycle, more than twice its theoretical value, and maintains its initial capacity after 50 cycles. Contrary to previous reports, we find that a mechanism for the high and reversible lithium-storage capacity of the mesoporous molybdenum dioxide electrode is not based on a conversion reaction. Insight into the electrochemical results, obtained by in situ X-ray absorption, scanning transmission electron microscopy analysis combined with electron energy loss spectroscopy and computational modelling indicates that the nanoscale pore engineering of this transition metal oxide enables an unexpected electrochemical mass storage reaction mechanism, and may provide a strategy for the design of cation storage materials for battery systems.

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