能量转移型聚芴类发光材料的合成与性能

本论文是以合成高性能的聚合物电致发光材料为目的，从材料合成的角度出发，以蔡酞亚胺衍生物为构造单元，采用Suzuki聚合反应合成了主链或侧链含有蔡酞亚胺衍生物基元的聚合物材料，并通过能量转移的方法，实现了发光颜色的改变和固态光致荧光量子效率的提高。1.合成了一种侧链上含有蔡酞亚胺衍生物基元的聚菊类聚合物，该蔡酞亚胺衍生物基元通过一柔性链间隔与聚菊主链相连。通过调节共聚单体的投料比，得到了一系列具有不同蔡酚亚胺衍生物基元含量的高荧光量子效率的聚合物，对其热性能和一佩发光性能进行了研究，结果表明所有的聚合物均有较高的热稳定性；其光致发光和电致发光J胜能与聚合物中蔡 酞亚胺衍生物基元的含量有密切的关系。蔡酞亚胺衍生物基元含量在一 特定范围内，聚合物的固态荧光量子效率达到最大值，且其双层器件的 亮度也为最高。2.对聚合物溶液和固态的吸收光谱和发射光谱的异同的研究，确证了能量转移现象的存在和对聚合物的发光颜色的调节作用。聚合物蔡酞亚胺衍生物基元含量由高到低变化时光致荧光发射波长发生相应蓝移，但其电致荧光发射波长为一定值的现象表明该类聚合物的光致荧光发射和电致荧光发射具有不同的机理。3.将蔡酞亚胺衍生物基元引入共扼主链，合成了一利“新的聚荀类高分子。该分子和聚菊分子相似均具有较高的热稳定性。该类聚合物分子内及分子间也存在能量转移现象。通过调节聚合物中蔡酞亚胺衍生物基元的含量可实现聚合物的光致荧光从橘红色到黄色的调节。一该类聚合物的电致荧光较光致荧光有所蓝移，其随蔡酞亚胺衍生物基元含量的改变而变化趋势与光致荧光相同，表明两种荧光发射具有相同的发射机理。其双层电致发光器件具有较好的性能。

联萘基手性联吡啶的合成及其应用

本论文以手性联萘酚为手性源，合成一系列联蔡基手性联毗陡及其衍生物，歼探讨了部分手性配体在不对称催化氢转移等反应中的应用。同时，通过部分配体与金属离子配位合成了旋光纯手性金属配合物，并对其溶液性质进行了深入研究。主要工作和结论如下：利用Krohnke方法，从（R）-6-乙酞基-2，2'-二甲氧基-1，1'-联萘简洁地合成了6-[6-((R)-2,2'-二甲氧基-1，1'-联萘基）]-2，2'-联吡啶及其衍生物（R)-1a-e。在相似条件下，合成了6，6'-二［6-（2，2'-联吡啶基）］-1，1'-联萘衍生物（R）-27-b。利用Suztlki偶联反应，对化合物（R）-1e进一步进行修饰得到了高产率的6-芳基-6'-[6-((R)-2,2'-二甲氧基-1,1'-联萘基）〕-2，2'-联吡啶(R)-1f-i。通过（R）3-（4，4，5：5-四甲基-1，3，2-二唑硼烷基）2，2'-乙氧基-1,1'-联萘与6-溴-2，2'-联吡啶及其衍生物的Suzuki偶联合成了四种手性6-［3-（（R）-2，2'-乙氧基-1，1'-联萘基）］-2，2'-联吡啶衍生物（R）-3a-d。将（R）-27b与AgSO3CF3进行配位合成Ag（I）配位聚合物35。固态下，35具有M构型的无限单股螺旋结构，且每个Ag（I）中心的手性受到配体，扫联蔡基的控制，其构型为Λ。在用MS、CD、UV及NMR对配合物35的溶液性质进行深入研究时发现，在溶液中配合物35离解为剂聚体，同时齐聚体之间存在快速平衡，且平衡随浓度、温度等条件的不同而发生改变，配体的平衡构象也相应被调整。另外，合成了Ag（I）与(R)-1d的单核配合物34，其洛液表现出与配台物35相似的性质。探讨了1a-i在苯乙酮氢转移还原、苯乙烯环丙烷化等不对称催化反应中的应用。在这些反应中，大部分配体表现出很好的反应活性，但立体选择性比较差。以(S)3，3'-二（4，4，5．5-四甲基-1，3，2-唑硼烷基于-2，2'-二（甲氧亚甲氧基）-1,1'-联萘为原料与2-溴吡啶及其衍生物先进行Stlzuki偶联，再经水解反应较高产率地合成了C2-对称性新型（S）-3，3'-二吡啶丛联茶酚衍生物（S）-38a-d。

The growth and characterization of GaN grown on a gamma-Al2O3/(001) Si substrate by metalorganic vapor phase epitaxy

Wurtzite single crystal GaN films have been grown onto a gamma-Al2O3/Si(001) substrate in a horizontal-type low pressure MOVPE system. A thin gamma-Al2O3 layer is an intermediate layer for the growth of single crystal GaN on Si although it is only an oriented polycrystal film as shown by reflection high electron diffraction. Moreover, the oxide is not yet converted to a fully single crystal film, even at the stage of high temperature for the GaN layer as studied by transmission electron microscopy. Double crystal x-ray linewidth of (0002) peak of the 1.3 mu m sample is 54 arcmin and the films have heavy mosaic structures. A near band edge peaking at 3.4 eV at room temperature is observed by photoluminescence spectroscopy. Raman scattering does not detect any cubic phase coexistence.

Growth and characterization of GaN on LiGaO2 and LiAlO2

The nearly lattice-matched LiGaO2 and LiAlO2 substrates have been used for the growth of GaN by LP-MOVPE. GaN epilayers have been grown on the two substrates at very low input partial pressure of hydrogen and relatively low growth temperature. The difference in the growth rate, crystal and optical qualities of hexagonal GaN epilayers grown on LiAlO2 and LiGaO2 substrate with two polar domains are investigated. LiAlO2 and LiGaO2 single crystal with a single domain structure and an adequate surface plane are promising substrates for the growth of high quality of hexagonal GaN thin films.

Yellow luminescence mechanism and persistent photoconductivity in n-GaN single crystal films grown on alpha-Al2O3(0001) substrates by LP-MOCVD

Unintentionally doped and Si-doped single crystal n-GaN films have been grown on alpha-Al2O3 (0001) substrates by LP-MOCVD. Room temperature photoluminescence measurement showed that besides the bandedges, the spectrum of an undoped sample was a broad deep-level emission band peaking from 2.19 to 2.30eV, whereas the spectrum for a Si-doped sample was composed of a dominant peak of 2.19eV and a shoulder of 2.32eV. At different temperatures, photoconductance buildup and its decay were also observed for both samples.. The likely origins of persistent photoconductivity and yellow luminescence, which might be associated with deep defects inclusive of either Ga vacancy(V-Ga)/Ga vacancy complex induced by impurities or N antisite (N-Ga), will be proposed.

Studies on the exotic structure of Al-23

The longitudinal momentum distribution (P-//) of fragments after one-proton removal from Al-23 and reaction cross sections (sigma(R)) for Al-23,Al-24 on carbon target at 74A MeV have been measured simultaneously. An enhancement in sigma(R) is observed for Al-23 compaxed with Al-24. The full width at half maximum of the P-// distribution for Mg-22 fragments has been determined to be 232 +/- 28 MeV/c. Analysis of P-// using the Few-Body Glauber Model indicates a dominant d-wave configuration for the valence proton in the ground state of Al-23. The exotic structure in Al-23 is discussed.

Projectile fragmentation of Kr-86 at 64 MeV/nucleon

We measured fragmentation cross sections produced using the primary beam of Kr-86 at 64 MeV/nucleon on Be-9 and Ta-181 targets. The cross sections were obtained by integrating the momentum distributions of isotopes with 25 <= Z <= 36 measured using the RIPS fragment separator at RIKEN. The cross-section ratios obtained with the Ta-181 and Be-9 targets depend on the fragment masses, contrary to the simple geometrical models. We compared the extracted cross sections to EPAX; an empirical parametrization of fragmentation cross sections. Predictions from current EPAX parametrization severely overestimate the production cross sections of very neutron-rich isotopes. Attempts to obtain another set of EPAX parameters specific to the reaction studied here to extrapolate the neutron-rich nuclei more accurately have not been very successful, suggesting that accurate predictions of production cross sections of nuclei far from the valley of stability require information of nuclear properties that are not present in EPAX.

Measurement of K*(892)(0) and K-0 mesons in Al plus Al collisions at 1.9A GeV

A new measurement of subthreshold K*(892)(0) and K-0 production is presented. The experimental data complete the measurement of strange particles produced in Al + Al collisions at 1.9A GeV measured with the FOPI detector at SIS at GSI (Darmstadt). The K*(892)(0)/K-0 yield ratio is found to be 0.0315 +/- 0.006(stat.) +/- 0.012(syst.) and is in good agreement with the transport model prediction. These measurements provide information on the in-medium cross section of K+-pi(-) fusion, which is the dominant process in subthreshold K*(892)(0) production.

Synthesis and Properties of Carbazole Main Chain Copolymers with Oxadiazole Pendant toward Bipolar Polymer Host: Tuning the HOMO/LUMO Level and Triplet Energy

Three new carbazole copolymers, poly(9-(2,5-diarene-[1,3,4]oxadiazole)-carbazole-alt-9-(2-ethylhexyl)-carbazole-3,6-diyl)s (P1), poly(9-(2,5-diarene-[1,3,4]oxadiazole)-2, 7-carbazole-alt-9-(2-ethylhexyl)-3, 6-carbazole-diyl)s (P2), and poly(9-(2,5-diarene-[1,3,4]oxadiazole)-carbazole-alt-9-(2-ethylhexyl)-carbazole-2,7-diyl)s (P3), were synthesized by the Suzuki coupling reaction

Phosphonate-Functionalized Polyfluorene as a Highly Water-Soluble Iron(III) Chemosensor

An anionic, phosphonate-functionalized polyfluorene, i.e., poly(9,9-bis(3'-phosphatepropyl)fluorene-alt-1,4-phenylene) sodium salt (PFPNa), has been synthesized by copolymerization of phosphonic acid-substituted 2,7-dibromofluorene and phenyldiboronic ester via direct Suzuki polycondensation reaction in DMF/water. Polymer PFPNa is highly soluble and emissive in water with a solubility of 60 mg/mL and a photoluminescence quantum yield of 75%. The absorption and fluorescence spectra of PFPNa are strongly dependent on pH value owing to the partial protonation of phosphate groups and the aggregation of the polymer chains.

Red-Emitting Polyfluorenes Grafted with Quinoline-Based Iridium Complex: "Simple Polymeric Chain, Unexpected High Efficiency"

A series of red-light emitting electrophosphorescent polyfluorenes (PFs) with varying content of a quinoline-based iridium complex, (PPQ)(2)Ir(acac) (bis(2,4-diphenylquinolyl-N,C-2') iridium(acetylacetonate)), in the side chain are synthesized by Suzuki polycondensation. Because of the efficient Forster energy transfer from the PF main chain to (PPQ)(2)Ir(acac) and direct charge trapping on the complex, the electroluminescent emission from PF is nearly completely quenched, even though the amount of iridium complex I incorporated into the polymers is as low as 1 mol %. Based on a single-layer device configuration, a luminous efficiency of up to 5.0 cd A(-1) with a luminance of 2000 cd m(-2) and Commission Internationale de L'Eclairage coordinates of (0.63, 0.35) (x, y) is realized, which is far superior to that of previously reported red-light emitting PFs containing benzothiazole- and isoquinoline-based iridium complexes.

Water-soluble phosphate-functionalized polyfluorene as fluorescence biosensors toward cytochrome c

An anionic water-soluble polyfluorene derivative, poly(9,9-bis(6'-phosphatehexyl)fluorene-alt-1,4-phenylene) sodium salt (PFHPNa), was synthesized by Suzuki coupling reaction in DMF/water. Polymer PFHPNa was well soluble in water with a strong blue fluorescence emission. Effect of the side chain length on fluorescence sensory properties was studied by comparing quenching efficiencies toward different quenchers of PFHPNa with a reported polymer poly(9,9-bis(3'-phosphatepropyl)fluorene-alt-1,4-phenylene) sodium salt (PFPPNa), which have different side chains in length. For small molecular quenchers (methylviologen, MV2+) and meso-5,10,15,20-tetrakis-(N-methyl-4-pyridyl)porphine (TMPyP4), polymer PFHPNa had lower sensitivity due to the much longer side chain length. The positively charged metalloprotein cytochrome c could quench fluorescence of conjugated polymers via energy transfer and electron transfer.

One-step synthesis of palladium/SBA-15 nanocomposites and its catalytic application

Well-dispersed palladium nanoparticles in mesoporous SBA- 15 SiO2 were prepared in a facile one-step approach during sol-gel route under reductive atmosphere. X-ray diffraction (XRD) results indicate that as-synthesized nanocomposites basically remain ordered two-dimensional hexagonal mesostructure while transmission electron microscopy (TEM) study exhibits a well dispersion of palladium nanoparticles within the mesoporous SBA-15 channels. The size of Pd nanoparticles is approximately in the range of 5-10nm. However, the resulting nanocomposites exhibit a highly catalytic activity and reused ability at least after five recycles without ligand in air for both the Suzuki and Heck coupling reactions.

Synthesis and applications of 3-[6-(hydroxymethyl)pyridin-2-yl]-1,1 '-bi-2-naphthols or 3,3 '-bis[6-(hydroxymethyl)pyridin-2-yl]-1,1 '-bi-2-naphthols

A series of new 1,1'-bi-2-naphthol (BINOL) derived ligands, 3-[6-(hydroxymethyl)pyridin-2-yl]-BINOLs or 3,3'-bis[6(hydroxymethyl)pyridin-2-yl]-BINOLs, bearing one or two chiral pyridinylmetlianols attached to a binaphthyl skeleton, have been synthesized using the Suzuki cross-coupling reaction. The resulting compounds have been used as ligands in the enantioselective addition of diethylzinc to aldehydes; the products were obtained with up to 96% ee.

Synthesis and characterization of white-light-emitting polyfluorenes containing orange phosphorescent moieties in the side chain

Two orange phosphorescent iridium complex monomers, 9-hexyl-9-(iridium (III)bis(2-(4'-fluorophenyl)-4-phenylquinoline-N, C-2')(tetradecanedionate-11,13))-2,7-dibromofluorene (Br-PIr) and 9-hexyl-9-(iridium(III)bis(2-(4'-fluorophenyl)-4-methylquinoline-N, C-2')(tetradecanedionate-11,13))-2,7-dibromofluorene (Br-MIr), were successfully synthesized. The Suzuki polycondensation of 2,7-bis(trimethylene boronate)-9,9-dioctylfluorene with 2,7-dibromo-9,9-dioetylfluorene and Br-Plr or Br-MIr afforded two series of copolymers, PIrPFs and MIrPFs, in good yields, in which the concentrations of the phosphorescent moieties were kept small (0.5-3 mol % feed ratio) to realize incomplete energy transfer. The photoluminescence (PL) of the copolymers showed blue- and orange-emission peaks. A white-light-emitting diode with a configuration of indium tin oxide/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)/PIr05PF (0.5 mol % feed ratio of Br-PIr)/Ca/Al exhibited a luminous efficiency of 4.49 cd/A and a power efficiency of 2.35 lm/W at 6.0 V with Commission Internationale de L'Eclairage (CIE) coordinates of (0.46, 0.33). The CIE coordinates were improved to (0.34, 0.33) when copolymer MIr10PF (1.0 mol % feed ratio of Br-MIr) was employed as the white-emissive layer. The strong orange emission in the electroluminescence spectra in comparison with PL for these kinds of polymers was attributed to the additional contribution of charge trapping in the phosphorescent dopants.