| The purpose of the research covered in this thesis is the synthesis of single-source molecular precursors having a desired metal stoichiometry followed by the preparation of the corresponding binary metal alloy/Vulcan carbon nanocomposites. The obtained nanocomposites have been characterized by powder X-ray diffraction and transmission electron microscopy (TEM) to gain information about particle size and morphology, and by EDS and elemental analyses to determine the metal/metal stoichiometries. The experimental results presented in this thesis specifically relate to the synthesis and characterization of nanocomposite materials that might serve as more effective catalysts in proton exchange membrane (PEMFC) and direct methanol fuel cells (DMFC).; For this study, Pt-Mo and Mo-Ru alloy compositions have been targeted for investigation. Pt-Mo alloys have known activity as CO-tolerant anode catalysts for PEMFCs. Successful preparation of Pt3Mo1, Pt 1Mo1, and Pt1Mo2/Vulcan carbon nanocomposites by the thermal decomposition of single-source molecular precursors is presented in Chapter II. Chapter IV describes a full profile Rietveld refinement of powder XRD scans of these materials. Chapter III describes a preparation of Mo-Ru alloy for investigation as methanol-tolerant cathode catalysts in DMFCs. Powder XRD investigation of a ternary Pt Pt1Ru 1Px alloy is described in Chapter V. Although the focus of this research is the preparation and characterization of these specific types of metal alloy/carbon nanocomposite materials, a review of fuel cell design and of the catalytic chemistry occurring in PEMFCs and DMFCs is provided in Chapter I. |
