Dissertation > Excellent graduate degree dissertation topics show

The Synthesis and Properties of Functional Materials with Silicon

Author: ZhangZhengHua
Tutor: XuWeiJian
School: Hunan University
Course: Chemical Engineering and Technology
Keywords: Hyperbranched Polysilane Blue Fluorescence Silicon Nanotubes Organotin Dimer Hydrosilylation
CLC: TN304.12
Type: PhD thesis
Year: 2008
Downloads: 404
Quote: 0
Read: Download Dissertation

Abstract


Polymer optoelecteic materials have already applied in the field of piant display and solar cell technology and display a bright future. aconjugated polysilanes are one of the promising materials of them. Hyperbranched polysilanes (HYPS) were synthesized by two monomers via Wurtz-type reaction. The structures of HYPS were characterized by GPC, IR, NMR, XRD and SEM. HYPS show a strong absorption belt within 280-3 50nm and have high thermal decomposition temperature and glass transition temperature. Due to the bright blue fluorescence around 455nm, HYPS could be a kind of blue light emission polymer materials. A nove hyperbranched polysilane/fullerene composite (HYPS-C60) was prepared using in-situ polymerization. HYPS-C60 as an electron donor/acceptor composite may have well defined interpenetrating structure because of 3-D structure of both hyperbranched polysilane and fullerene. The structures, properties of HYPS-C60 were also characterized by various methods. The characteristic photoluminescence(PL) peak of HYPS was significantly quenched in C60/HYPS mixtures, which indicated the presence of an electron-transfer process between C60 and HYPS. Fullerene (C60)/ Hyperbranched polysilane(HYPS) photovoltaic devices were fabricated with various concentrations of C60 and their photovoltaic properties were investigated. The best photovoltaic device performance has been obtained for 30%C60/HYPS mixture: Isc = 0.06292 mA/cm2, Voc = 0.4811V, FF = 0.25, andn = 0.0076% under AM1.5 illumination( 100mW/cm2).Since silicon nanornaterials are compatible with modern silicon technology, they are promising in nanodevices and will dominate in semiconductor industry. Silicon nanotubes were prepared using SiO as the starting material and de-ionized water as reaction medium under 470℃with the pressure near 6.8-8.4 MPa in a sealed reaction kettle. The structure and composition of the production were characterized by transmission electromicroscopy (TEM), high-resolution transmission eleetromicroscopy (HRTEM), selected area electron diffraction (SAED), energy dispersive 3C-ray spectrum (EDS), and PL. The self-assemble growth mechanism of silicon nanotubes by hydrothermal method was discussed.As a kind of very important raw materials of polysiloxane, alkyloxysilanecan be prepared by the hydrosilylation of carbonyl compounds and triethylsilane. Organotin oxo clusters have arisen the interest of chemists due to their excellent catalytic activity in several kinds of organic reactions. The compound [Bu2Sn(OH)OTf]2 can catalyze the hydrosilylation of aldehydes. In this kind of reactions, the compound [Bu2Sn(OH)OTf]2 exhibits very high catalytic activity and chemoselectivity, that is, it act only on the aldehyde not affecting other active groups.

Related Dissertations

  1. Synthesis and Application of Karstedt Catalyst Used for Hydrosilylation,TQ426.9
  2. The Application and Study of Spectrometry in the Hydrolysates of Nucleic Acid Analysis,Q52-3
  3. The Study of Novel Transition Metal Catalysts for Hydrosilylation Reaction of Alkenes,O643.32
  4. Silicone dendrimers - synthesis and catalytic properties of transition metal complexes,O643.32
  5. Studies on Rhodium-Catalyzed Asymmetric Cyclization Reactions of 1, 6-Enynes,O643.32
  6. The Study of Supported Platinum Complexes Catalysts for Hydrosilylation Reaction of Alkenes,O643.32
  7. The Synthesis and Application of Organotin Oxo Clusters,O643.32
  8. Preparation and Micellization of Amphiphilic Polysiloxane Copolymers,O634.41
  9. Nanomaterials on phenothiazine drugs with DNA research impact,TB383.1
  10. PES - polysiloxane graft polymer synthesis and properties of,O634.41
  11. Self-healing Polymer Composites,TB381
  12. Synthesis of Mesoporous Silica with Controlled Morphology and the Regulation of Nanochannel Direction of Mesopores,O613.72
  13. One -dimensional silicon nano- materials and nickel-silicon heterojunction nanowire Preparation and Characterization,TB383.1
  14. For olefin hydrosilylation rhodium complexes / ionic liquid catalyst system research,O643.32
  15. First-Principles Study of the One-dimensional Nanomaterials,TB383.1
  16. Asymmetric Hydrogenation and Functionalization of Calix [4] Arenes and Their Catalysis,O643.32
  17. Study on the Synthesis and Properties of Multifunctional Polyhedral Oligomeric Silsesquioxane and Its Polymer Hybrid Materials,O631.3
  18. Synthesis and Characterization of the Self-healing Monomers for Polymer Composites,O631.3
  19. 3,3 - dinitro-1 - butene synthesis and polymerization studies,O633.2
  20. Study on Synthesis and Application of Polyoctylmethylsiloxane,O634.41

CLC: > Industrial Technology > Radio electronics, telecommunications technology > Semiconductor technology > General issues > Material > Elemental semiconductors > Silicon
© 2012 www.DissertationTopic.Net  Mobile