溶剂热/水热条件下空旷结构草酸锌的合成

应用水热法及溶剂热方法，选择两种模板剂1，2-丙二胺和4，5-二氮芴-9-酮连氮(L)设计合成了草酸锌空旷结构材料[Zn₂(C₂O₄)3][C₃H₁₂N₂]·H₂O (Ⅰ)和[Zn₂(C₂O₄)₃]·L·6[H₃O] (Ⅱ)，使用CHN元素分析、     

Vanadium Oxide: From Gels to Nanotubes

Vanadium oxide nanotubes (VO _x -NT) have been prepared by mixing hexadecylamine with V₂O₅·nH₂O gels. This procedure was followed by an hydrothermal treatment (150–180°C, 2–7 days) which leads to a large quantity of VO _x -NT. SEM and XRD analysis have been used to optimize the temperature and reaction time required for production of VO _x -Nt and morphology of the nanotubes investigated by TEM.     

The effect of the hydration degree on the hydrothermal and thermo-oxidative stability of some collageneous matrices

The methods of the thermal analysis (TG, DTG and DTA) were used in order to investigate the effect of the hydration degree on the thermal behaviour of some collageneous matrices. It was pointed out that the degradation of hydrated collagen in the temperature range 20-400°C occurs through two successive processes accompanied by mass losses. The first process, consisting in the collagen dehydration, is endothermic and takes place in the temperature range ≈25 - ≈125°C. The second process is exothermic and consists in the decomposition and/or thermo-oxidation of dry collagen. The thermal parameters of both processes depend on the hydration degree of collagen. The observed dependencies show that the hydrothermal and thermo-oxidative stability of collagen are strongly correlated with its water content. This revised version was published online in July 2006 with corrections to the Cover Date.     

A series of Wells-Dawson and Keggin-based compounds with uncoordinated S donors as fluorescence sensors to Hg2+

Abstract

Through using a S-containing ligand 2,2’-dimethyl-4,4’-bithiazole (dbt), a series of Wells-Dawson and Keggin-based compounds, {Zn(dbt)₃}{Zn(dbt)₂(H₂O)}₂{HP₂W^VW^VI₁₇O₆₂}·4H₂O (1), {Cd(dbt)₂(H₂O) (HP₂W^VW^VI₁₇O₆₂)}{Cd(dbt)₃}{Cd(dbt)₂(H₂O)}·13H₂O (2), {Cd₂(dbt)₄Cl} {PW₁₂O₄₀} (3) and {Cd₂(dbt)₄}{SiW₁₂O₄₀} (4), were synthesized under hydrothermal conditions and structurally characterized. In 1, there are three dissociated subunits: Wells-Dawson anion, {Zn(dbt)₃}²⁺ and {Zn(dbt)₂(H₂O)}²⁺. In 2, the mono-supporting Wells-Dawson anions exhibit abundant hydrogen bonding interactions with discrete {Cd(dbt)₃}²⁺ and {Cd(dbt)₂(H₂O)}²⁺ mononuclear coordination complexes, constructing a supramolecular layer. Compound 3 has a binuclear Cd cluster {Cd₂(dbt)₄Cl}⁴⁺ with a Cl as a bridging atom. The Keggin anions link these binuclear Cd clusters alternately to build a 1D chain. In 4, a pair of {Cd(dbt)₂}²⁺ subunits connect adjacent Keggin anions and a 1D chain is formed. In these four compounds, only the N donors coordinate with Zn or Cd and the S atoms are uncoordinated. These compounds show good fluorescence sensing performance to Hg²⁺. We also studied the electrochemical and photocatalytic properties of 1–4. These compounds also can act as electrochemical sensors for the detection of nitrite.     

Hierarchical FeCo2S4@FeNi2S4 Core/Shell Nanostructures on Ni Foam for High-Performance Supercapacitors

The design of electrode materials with rational core/shell structures is promising for improving the electrochemical properties of supercapacitors. Hence, hierarchical FeCo₂S₄@FeNi₂S₄ core/shell nanostructures on Ni foam were fabricated by a simple hydrothermal method. Owing to their structure and synergistic effect, they deliver an excellent specific capacitance of 2393 F g⁻¹ at 1 A g⁻¹ and long cycle lifespan as positive electrode materials. An asymmetric supercapacitor device with FeCo₂S₄@FeNi₂S₄ as positive electrode and graphene as negative electrode exhibited a specific capacitance of 133.2 F g⁻¹ at 1 A g⁻¹ and a high energy density of 47.37 W h kg⁻¹ at a power density of 800 W kg⁻¹. Moreover, the device showed remarkable cycling stability with 87.0 % specific-capacitance retention after 5000 cycles at 2 A g⁻¹. These results demonstrate that the hierarchical FeCo₂S₄@FeNi₂S₄ core/shell structures have great potential in the field of electrochemical energy storage.     

有双重固硫作用的PEDOT包覆MnO2纳米管阴极用于高性能的锂硫电池

制备了α-MnO₂纳米管作为硫的宿主材料,将硫填充到α-MnO₂管的中空部分,并通过原位聚合法在α-MnO₂外层包覆一层薄层聚（3,4-乙烯二氧噻吩）（PEDOT）进一步束缚硫。这样一种双重固硫的阴极材料S@α-MnO₂-PEDOT在锂硫电池中体现出了高的性能。在电流密度1 675 mA·g^-1（1C）下循环200圈,容量为774.4 mAh·g^-1,且在电流密度为3 350 mA·g^-1（2C）下容量达854.1 mAh·g^-1,体现出良好的循环稳定性和倍率性能。这些显著的性能得益于阴极材料新颖的结构。在这种结构中,α-MnO₂纳米管不仅能对硫起到物理限制作用,而且增强了硫宿主材料和多硫化物间的化学相互作用。同时,PEDOT的引入增强了含硫纳米复合材料的导电性,并进一步减少了由于体积变化和多硫化锂的过度溶解引起的硫的损失。     

Hydrothermal Synthesis, Crystal Structure and Thermal Stability of [Ni(phen)3]·(C8H12O4)·(H2O)14

One novel complex [Ni(phen)3]·(C8H12O4)·(H2O)14 with hexane dicarboxylic acid and 1,10-phenanthroline has been hydrothermally synthesized and characterized. Crystal data: monoclinic, space group C2/c, a = 2.3475(5), b = 1.2208(2), c = 1.9499(4) nm, β = 114.682(3)o, V = 5.0778(16) nm3, Dc = 1.339 g/cm3, Z = 4, μ(MoKα) = 0.458 mm-1, F(000) = 2168, GOOF = 1.014, R = 0.0401 and wR = 0.0961. The nickel(Ⅱ) center in the title complex is coordinated with six nitrogen atoms of three 1,10-phenanthroline molecules, giving a distorted octahedral coordination geometry. However, the nickel(Ⅱ) ion does not coordinate to the hexane dicarboxylic acid. The complex molecules form a 3D structure through hydrogen bonds. TG analysis shows that the title complex is stable below 240.0 ℃.     

钛酸盐(钴、镓)沸石分子筛的合成与表征

钛酸钴;钛酸镓;水热合成;钛酸盐(钴、镓)沸石分子筛的合成与表征     

Transition metal coordination polymers with polycarboxylic acid as bridging ligands: Synthesis and structure characterization of [Fe(μ4-bta)0.5(phen)(OH)]<Subscript>n</Subscript>

A new 2D (two-dimensional) coordination polymer, [Fe(μ4-bta)o.5(phen)(OH)]_n (1), has been hydrothermally synthesized with FeCl₃ 6H₂, Na₄bta (h₄bta = 1,2,4,5-benzentetracarboxylic acid), 1,10-phen (1,10-phenanthroline) and H₂O as raw materials. The crystals of the compound belong to monoclinic P2₁/n space group, a = 1.0129(2) nm, b = 0.9265(2) nm, c = 1.5696(3) nm, β=91.37(3)°V=1.4721(5) nm³,Z=3, final R₁=0.0292, wR ₂=0.0798 for 2572 [/>2σ(/)] observed reflections. The result of structure determination shows that in the compound each bta ligand is connected with four Fe³, forming a new μ4-coordination mode. Four deprotonated carboxylic groups of bta link to Fe³ ions alternatively through monodentate and bidentate coordination fashion, constructing 2D layer network. The measurement of variable temperature magnetic susceptibility indicates that there exist antiferromagnetic interactions between Fe³ ions in the compound. The TGA spectrum displays relatively fine thermal stability of the compound. In addition, IR and UV-Vis spectra of compound 1 have also been measured.     

空心微球表面定向生长TiO2纳米棒及其光催化性能研究

通过表面溶胶-凝胶处理和水热反应成功制备出包覆有二氧化钛纳米棒的复合空心微球. 用扫描电子显微镜(SEM)和X射线衍射仪(XRD)等表征了所得产品, 探索了水热反应时间、煅烧时间对产物形貌和结构的调控作用, 并对产物光催化降解亚甲基蓝进行了研究. 结果表明, 所制备的表面包覆有二氧化钛纳米棒的复合空心微球在紫外光照射下可将亚甲基蓝完全降解. 该材料质轻, 可浮于水面, 有望成为一种新型光催化剂, 应用于治理水体表面的大面积污染.