A hierarchical N-doped carbon nanotube-graphene hybrid nanostructure (NCNT-GHN), in which the graphene layers distributed inside the CNT inner cavities, is designed to support noble metal (e.g. PtRu) nanoparticles efficiently. Well-dispersed PtRu nanoparticles with diameters of 2-4 nm are immobilized onto NCNT-GHN supports by a low-temperature chemical reduction method without requiring any pretreatment. Compared with conventional CNTs and commercial catalyst, much enhanced catalytic performance is achieved by a synergistic effect of the hierarchical structure (graphene-CNT hybrid) and electronic modulation (N-doping) during the methanol electrooxidation reaction. An improved singlecell performance with long-term stability is also demonstrated by using NCNT-GHN as catalyst support. These results explain previously reported findings on highly dispersed gold nanoparticles, in which the peripheral atoms are positively charged

PtRu alloy nanoparticles (24 +/- 1 wt %, Ru/Pt atomic ratios = 0.91-0.97) supported on carbon nanofibers (CNFs) were prepared within a few minutes by using a microwave-polyol method. Three types of CNFs with very different surface structures, such as platelet, herringbone, and tubular ones, were used as new carbon supports. The dependence of particles sizes and electrochemical properties on the structures of CNFs was examined. It was found that the methanol fuel cell activities of PtRu/CNF catalysts were in the order of platelet > tubular > herringbone. The methanol fuel cell activities of PtRu/CNFs measured at 60 degrees C were 1.7-3.0 times higher than that of a standard PtRu (29 wt %, Ru/Pt atomic ratio = 0.92) catalyst loaded on carbon black (Vulcan XC72R) support. The best electrocatalytic activity was obtained for the platelet CNF, which is characterized by its edge surface and high graphitization degree.

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Nafion-1,2,3-triazole blend membranes were prepared by autoclave (AC) solution processing mixing of Nafion (R) solution (5% solution in 1- and 2-propanol and H2O) and 1,2,3-triazole. The blend membranes were very flexible, transparent, homogeneous, and stable even after boiling in water and treatment in 1M H2SO4. FTIR and NMR results suggested that 1- and 2-propanol of Nafion solution reacted with 1,2,3-triazole under the catalytic effect of the Nafion's acid side chain. IV performance of blend membranes was tested using a single membrane electrode assembly (MEA) cell. The cell performance of Nafion-5wt.% 1,2,3-triazole blend membrane was higher than that of the Nafion 112 at cell temperatures over 100 degrees C indicating that it is possible to use Nafion-1,2,3-triazole blend membrane as an electrolyte for high temperature PEMFCs

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