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81.
The first example of a unidimensional zirconium hydroxide fluoride was synthesized under mild solvothermal treatment and characterized by X-ray diffraction and thermal techniques. Monoprotonated ethylenediamine cations reside between the anionic chains. Crystal data for this material are as follows: [C2N2H9][Zr(OH)2F3], M=243.35, orthorhombic, space group Pca21, a=6.8016(13), b=6.1393(12), , , , Z=4, , μ(Mo-Kα)=1.777 mm−1, . The material transforms to an unknown layered material at ∼175 °C, a common occurrence for 1D structures where the chains are arranged in hydrogen-bonded layers and separated by interlayer organoammoniums. Collapse to the known condensed mineral phase Zr(FO)2.7 occurs at ca. 275 °C before finally transforming to the baddeleyite form of ZrO2 at ca. 460 °C. 相似文献
82.
LUAN Chun-hong GENG Yu-jing YU Qin-qin CAO Li-li LIAN Gang CUI De-liang 《高等学校化学研究》2012,28(4):747-751
Al2O3 porous nanosolid was prepared via solvothermal hot-press(SHP) method. The dielectric constant of Al2O3 porous nanosolid is as low as 2.34, while its compressive strength is very poor. In order to improve the compressive strength and maitain low dielectric constant, polyimide was introduced to prepare Al2O3/polyimide composite porous nanosolid. Compared to Al2O3 porous nanosolid, Al2O3/polyimide composite porous nanosolid possesses much higher compressive strength, which reaches its saturation value when the mass loading of polyimide is 7.75%. In addition, the in situ Fourier transformation infrared(FTIR) monitoring result reveals that Al2O3/polyimide composite porous nanosolid is stable up to 400℃. 相似文献
83.
以十二硫醇和聚乙烯吡咯烷酮(PVP)为结构导向剂、乙二醇和乙二胺为混合溶剂,利用溶剂热技术成功地制备了Co粒子,并用XRD、SEM、TEM、HRTEM及SQUID对材料的晶体结构、形貌及磁性进行研究. 结果表明:Co粒子属hcp相,呈六方片状,直径约为2 μm,厚度约为80 nm,大量的六方片相互交叉连接成链式结构,并且六方薄片由更为细小的丝带状的纳米片(厚度约为10 nm)构成;室温下样品表现出良好的铁磁性特征,其饱和磁化强度Ms、剩余磁化强度Mr及矫顽力分别为126.6 emu/g、13.7 emu/g和163.4 Oe. 相似文献
84.
Donghui Zhang ;Lu Shang ;Jun Shen ;Zhan Shi ;Lizhu Wu ;Chenho Tung ;Tierui Zhang 《Particuology》2014,(4):51-55
Perfect truncated octahedral magnetite crystals were successfully synthesized from FeCl_3·6H_2O and poly(acrylic acid)(PAA)in an alkaline ethylene glycol solution via a mild one-step solvothermal process.The structure and morphologies of the obtained products were characterized by powder X-ray diffraction(XRD),Raman spectroscopy,scanning electron microscopy(SEM),and transmission electron microscopy(TEM).The effects of synthetic parameters including reaction temperature,reaction time,and the amount of alkali on the morphological evolution of the truncated octahedral magnetite crystals were systematically explored.160℃ was found to be the optimum temperature for the formation of truncated octahedral magnetite crystals.Below 160 ℃,little magnetite was formed.Above 160 ℃,the truncated octahedrons were gradually transformed into irregular-shaped polyhedrons.Alkali is indispensable in promoting the formation of magnetite at mild temperatures.The truncated octahedral magnetite crystals were found to be ferromagnetic and had a saturation magnetization of about 83 emu/g. 相似文献
85.
以乙醇为溶剂, 钛酸四丁酯为前驱体, 用溶剂热法制备了Ag表面修饰的负载型纳米二氧化钛光催化剂. 利用X射线衍射(XRD)、N2吸附-脱附(BET)、透射电子显微镜(TEM)、X射线光电子能谱(XPS)、紫外-可见(UV-Vis)光谱等技术对其进行了系统的表征, 以亚甲基蓝(MB)溶液的脱色降解为模型反应, 考察了不同Ag含量样品的光催化性能. 结果表明: 用溶剂热法制备的样品中TiO2皆为锐钛矿相, 金属Ag颗粒沉积在TiO2表面, 粒径为2 nm左右, 比表面积较溶胶凝胶法制备的样品大大增加, 最高可达151.44 m2·g-1; UV-Vis光谱和光催化实验表明: Ag修饰使TiO2对光的吸收能力大大增强, 吸收带边红移至可见光区, 亚甲基蓝在该复合材料上的光催化降解反应遵循一级反应动力学模型; 溶剂热法制备样品的光催化性能明显好于溶胶凝胶法制备的样品, 在紫外光和可见光下, Ag摩尔分数为5%的样品表现出最佳的光催化活性. 相似文献
86.
《Journal of Coordination Chemistry》2012,65(3):507-519
Solvothermal reaction of uranyl acetate and succinic acid in DMF resulted in formation of three uranyl coordination polymers, [(UO2)4(μ2-OH)7(OH)6]·2(H2O)·(H3O)·4NH2(CH3)2 (1), [(UO2)(μ2-OH)(OH)3]·2NH2(CH3)2] (2), and [(DMF)2(UO2)(μ2-OH)4(UO2))] (3). The products were characterized by elemental analysis, IR spectroscopy, X-ray single crystal, and powder diffraction. Structural analysis shows that 1 is a layer, 2 and 3 are 3-D network structures. 相似文献
87.
《Journal of Coordination Chemistry》2012,65(13):2335-2350
Solvothermal reactions of CdCl2·2.5H2O with 4,4′-bis(benzoimidazol-1-yl)bibenzene (bimbb) and 1,4-benzenedicarboxylic acid (1,4-H2bdc), 4,4′-biphenyldicarboxylic acid (4,4′-H2bpdb), 5-methyl-1,3-benzenedicarboxylic acid (5-Me-1,3-H2bdc), or 1,3,5-benzenetricarboxylic acid (H3btc) afforded four 3-D metal–organic frameworks, {[Cd2(1,4-bdc)2(bimbb)2]·H2O}n (1), {[Cd2(4,4′-bpdb)2(bimbb)(H2O)2]} n (2), [Cd2(5-Me-1,3-bdc)2(bimbb)] n (3), and {[Cd3(btc)2(bimbb)(H2O)2]·2H2O} n (4). Complexes 1–4 were characterized by elemental analysis, IR spectroscopy, powder X-ray powder diffraction, and single-crystal X-ray diffraction. 1 possesses a 3-D framework with 2-D undulated (8,4) layers which are further connected by bimbb pillars. 2 forms a 3-D pillared-layer framework constructed through 2-D undulated (4,4) layers and bimbb pillars. 3 has 1-D ribbons of [Cd4(5-Me-1,3-bdc)4] n which are linked by bimbb to form a 3-D structure. 4 exhibits a 3-D pillared-bilayer framework consisting of (6,3) double-decker [Cd9(btc)6(μ-OH2)6] n layers and bimbb pillars. The Schläfli symbols for the four frameworks are (42·63·8)(42·65·83) (1), (44·66) (2), (44·62)(46·64) (3), and (63)(610) (4). The photoluminescent properties of 1–4 were also investigated. 相似文献
88.
《Journal of Coordination Chemistry》2012,65(18):1997-2007
The reactions of m-H2BDC, NaOH with Cd(NO3)2?·?4H2O and Co(NO3)2?·?4H2O (m-BDC?=?1,3-benzene-dicarboxylate) in DMF gave two isostructural three-dimensional (3D) heterometallic coordination polymers: [CdNa(m-BDC)2]?·?[NH2(CH3)2] (1) and [CoNa(m-BDC)2]?·?[NH2(CH3)2] (2), respectively. The compounds were characterized by single-crystal X-ray diffraction, X-ray powder diffraction, ICP, TGA, IR, and photoluminescence spectroscopy. The crystal structures were determined by X-ray diffraction and refined by full-matrix least-squares methods to R?=?0.0221 and wR?=?0.0579 using 1925 reflections with I?>?2σ(I) for 1; and R?=?0.0654 and wR?=?0.1591 using 1881 reflections with I?>?2σ(I) for 2. Their frameworks are constructed from M–O–C (M?=?Na, Cd and Co) chains composed of alternating six-coordinate Na(I) centers and four-coordinate Cd(II) or Co(II) centers. These chains are further linked by m-BDC to form unusual 3D open-framework structures. 相似文献
89.
《Journal of Coordination Chemistry》2012,65(18):3316-3328
The reactions As2O3, Se and 1,10-phenanthroline (phen) with NiCl2 and ZnCl2 in water at 140°C for 5 days afforded selenidoarsenates [Ni(phen)3]2[As8Se14] (1) and [Zn(phen)3]2[As8Se14] (2), respectively. The reactions with CoCl2 and NiCl2 in CH3OH aqueous solution produced polyselenidoarsenates [Co(phen)3][As2Se6] (3) and [Ni(phen)3][As2Se6] (4). All transition metal ions are octahedrally coordinated by six nitrogen atoms and all arsenics are trigonal pyramidally coordinated by three seleniums. In 1 and 2, eight [AsSe3]3? trigonal pyramids joined via edge-sharing to form [As8Se14]4? with condensation grade of 0.571. [As8Se14]4? contains two As3Se3 and one As6Se6 heterocycles. The formations of the selenidoarsenate anion [As8Se14]4? in 1 and 2 and polyselenidoarsenate [As2Se6]2? in 3 and 4 show solvent effect on condensation of trigonal bipyramidal [AsSe3]3? units under solvothermal conditions. 相似文献
90.
《Journal of Coordination Chemistry》2012,65(10):1737-1743
A 2-D coordination polymer with mixed ligands, [Zn2(BDC)(4,4′-bipy) (HCOO)2] (1) (BDC, 1,4-benzenedicarboxylate; 4,4′-bipy, 4,4′-bipyridine), has been synthesized by solvothermal reaction. Compound 1 provides the first coordination polymer structure constructed by bridging BDC, 4,4′-bipy, and formate. Both BDC and 4,4′-bipy link zincs alternatively, resulting in a zigzag coordination chain; adjacent chains are further linked by formates to form an infinite extended 2-D folding screen layer. The synthesis mechanism and fluorescence property are discussed. 相似文献