UMD Theses and Dissertations

Permanent URI for this collectionhttp://hdl.handle.net/1903/3

New submissions to the thesis/dissertation collections are added automatically as they are received from the Graduate School. Currently, the Graduate School deposits all theses and dissertations from a given semester after the official graduation date. This means that there may be up to a 4 month delay in the appearance of a given thesis/dissertation in DRUM.

More information is available at Theses and Dissertations at University of Maryland Libraries.

Browse

Search Results

Now showing 1 - 1 of 1
  • Thumbnail Image
    Item
    Synthesis and Characterization of Binary Clusters to Controllable Binary Nanoparticles "The New Role of Zintl Anions"
    (2004-10-27) Moses, Melanie Jean; Eichhorn, Bryan W; Chemistry; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    Zintl anions are best described as polyatomic main group clusters (i.e. E73-; E = P, As, Sb) with structures characteristic of isoelectronic clusters (i.e. hydrocarbon and borohydride clusters). Combining these main group clusters and transition-metal precursors (Ni(COD)2; COD = cyclooctadiene, and Pd(PCy3)2; PCy3 = tricyclohexyl phosphine) with very labile ligands allows for the isolation of novel binary molecular clusters. The freedom these structures experience due to the absence of organic ligands lends itself to the very unique structure growth the binary clusters exhibit. Direct oxidation of these binary molecular clusters results in the formation of binary phases (i.e. PdAs2, NiAs, NiAs2). More control of the phase-specific binaries obtained can be achieved by controlling the reaction of the precursors, eliminating the need to isolate the clusters. Binary nanoparticles are in the forefront of heterogeneous catalyst development and application, making this an area of intense investigation. Structural characteristics of the binary clusters, [As@Ni12@As20]3-, [(Ni2Sb2)(Sb7)2]4-, [Ni5Sb17]4-, [Pd7As16]4- and [Pd2(E7)2]4- (E = P, As), and evidence for the formation of phase-specific binary nanoparticles (Ni5As2, Ni11As8, NiAs and NiAs2) under very mild conditions will be presented.