Ethanol and ethanol-water mixtures were converted directly into H2 with approximately 100% selectivity and >95% conversion by catalytic partial oxidation, with a residence time on rhodium-ceria catalysts of <10 milliseconds. Rapid vaporization and mixing with air with an automotive fuel injector were performed at temperatures sufficiently low and times sufficiently fast that homogeneous reactions producing carbon, acetaldehyde, ethylene, and total combustion products can be minimized. This process has great potential for low-cost H2 generation in fuel cells for small portable applications where liquid fuel storage is essential and where systems must be small, simple, and robust.

Multistep deposition and reactive decomposition of a precursor molecule containing one Pt and one Ru atom on herringbone graphitic carbon nanofibers (GCNFs) affords a Pt-Ru/GCNF nanocomposite containing Pt-Ru alloy nanoclusters widely dispersed on the GCNF support. The nanocomposite has a total metal content of 42 wt % with a bulk Pt/Ru atomic ratio of ca. 1:1, and metal alloy nanoclusters having average particle sizes of 6 nm as calculated from XRD peak widths or 7 nm as measured directly from TEM images. XRD and electrochemical analysis of the nanocomposite as-prepared and stored under ambient conditions reveals the presence of small amounts of Ru metal and oxidized metal species. Comparative testing of this nanocomposite and an unsupported Pt-Ru colloid of similar surface area and catalyst particle size as anode catalysts in a working direct-methanol fuel cell (DMFC) reveals a 50% increase in performance for the Pt-Ru/GCNF nanocomposite. More detailed study of the catalytic performance of metal alloy/GCNF nanocomposites as DMFC anode catalysts appears to be warranted.

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Thermal treatment of (η-C 2 H 4 )(Cl)Pt(µ-Cl) 2 Ru(Cl)(η 3 :η 3 -2,7-dimethyloctadienediyl) (1)/ Vulcan carbon composites under appropriate oxidizing and reducing conditions using microwave dielectric loss heating affords PtRu/Vulcan carbon nanocomposites consisting of PtRu alloy nanoparticles highly dispersed on a powdered carbon support. Two such nanocomposites containing 16 or 50 wt % total metal and alloy nanoclusters of 3.4-or 5.4nm average diameter are formed within only 100 or 300 s of total microwave heating. XRD and on-particle EDS analyses reveal that complex 1 serves as a reliable single-source molecular precursor for the formation of PtRu nanoparticles having a nearly 1:1 metal alloy stoichiometry. Preliminary measurements of the catalytic activity of these nanocomposites as supported direct methanol fuel cell (DMFC) anode catalysts indicate that the 50 wt % nanocomposite has a performance superior to that of a 60 wt % commercial catalyst and a normalized performance equivalent to that of a proprietary unsupported Pt 1 Ru 1 catalyst.