具有Keggin结构的多元杂多化合物的合成与光谱研究

本文合成了一些具有Ｋｅｇｇｉｎ结构的Ｐ－Ｖ－Ｍｏ－Ｗ四元杂多阴离子「ＰＶｘＭｏｙＷ１２－ｘ－ｙＯ４０」＾（３＋ｘ）－的化合物（其中,ｘ＝１,２和３）,并对其进行红外和拉曼光谱研究,可看到化合物的νａｓ（Ｍ＝Ｏｄ）、νａｓ（Ｍ－Ｏｂ－Ｍ）和νａｓＭ－Ｏｃ－Ｍ）的红外伸缩振动峰随着Ｖ原子数目的增加而红移;而钨原子数目的增加一般使之蓝移,但在所研究的ＰＶ２Ｍｏ９Ｗ和ＰＶ３Ｍｏ８Ｗ杂多化合物却出现略为反常     

具有Keggin结构的多元杂多化合物的合成与光谱研究Ⅱ

本文合成了一些具有Keggin结构的Si-V-Mo-W四元杂多阴离子[SiVxMoyW12-x-6O40]^(4 x)-的化合物（其中，x=1,2和3），并对其进行了红外光谱研究，可看到化合物的M＝Od，M－Ob-M和M－Oc－M的红外伸缩振动峰随着V原子数目的增加而红移；而钨原子数目的增加一般使之蓝移，因此推测出杂多化合物的酸性随着V数目的增加而减, 应性能则相反。这种变化规律与[PVxMoyW12-x-yo40]^(3 x)-相似。另外，可看到P系列的多元杂多酸（或杂多化合物）的配性大于相应的Si系列的酸性。     

钨锌杂多酸盐催化合成庚酸乙酯

合成了K8[FeZnW11O39(H2O)]、K8[NiZnW11O39(H2O)]和K8[CoZnW11O39(H2O)]3种具有Keggin结构的钨锌混配型杂多酸盐催化剂,以无水乙醇和庚酸为原料,催化合成庚酸乙酯。结果表明最佳反应条件为:催化剂用量为原料质量的1%,催化剂在连续使用6次情况下活性无明显下降,3种催化剂中K8[NiZnW11O39(H2O)]的催化活性最好。     

11-钨锌三元杂多阴离子层状化合物的合成、表征及催化活性

用离子交换法将具有K egg in结构11-钨锌三元杂多化合物K8[M ZnW11（H2O）O39]（M=Co2＋、N i2＋、Cu2＋、Cd2＋）嵌入到Zn2A l类水滑石中,得到层状化合物：Zn2A l-[M ZnW11（H2O）O39]（M=Co2＋、N i2＋、Cu2＋、Cd2＋）,并用XRD、IR、UV对其进行了表征。结果表明,杂多阴离子进入水滑石层间后,仍保留了其K egg in结构。利用层状化合物催化合成乙酸正丁酯考察其催化活性,结果表明,层状化合物在酯化反应中显示优良的催化性能。     

稀土硅钨杂多配合物与半菁复合材料的合成及光学性质

通过Keggin结构稀土硅钨杂多配合物K₁₃[Ln(SiW₁₁O₃₉)₂] (其中Ln=La,Ce,Pr,Nd,Sm,简写为Ln(SiW₁₁)₂)与碘化(E)-N-甲基-4-(2-(4-二甲氨基苯基)乙烯基)吡啶(C₁₆H₁₉N₂I,AI)反应,制备了一系列含轻稀土元素的硅钨杂多配合物与半菁衍生物的复合材料。应用元素分析和TG-DTA确定配合物的组成为(C₁₆H₁₉N₂)₁₀K₃[Ln(SiW₁₁O₃₉)₂]。利用红外光谱、紫外-可见光谱和荧光光谱研究了上述复合材料的光学性质及复合材料中无机组分与有机组分间的相互作用。     

三元杂多阴离子层状化合物的合成、表征及催化活性

用离子交换法合成了具有Keggin结构的三元杂多阴离子层状化合物LDH-K8[MnCu(H2O)W11O39],LDH-K8[MnFe(H2O)W11O39],LDH-K8[MnCo(H2O)W11O39]和LDH-K8[MnZn(H2O)W11O39],并用XRD、IR、UV对其进行了表征。结果表明:杂多阴离子进入水滑石层间后,仍保留了其Keggin结构。利用层状化合物催化合成乙酸正丁酯考察其催化活性,结果表明:层状化合物在酯化反应中显示优良的催化性能。     

石墨烯改性锡酸锌材料的光谱特性及其光催化性能

半导体光催化氧化技术在处理能源危机和环境污染问题方面有非常重要的应用。选取石墨烯对水热法制备的Zn₂SnO₄进行改性。通过透射电镜(TEM)观察其形貌特征,通过X射线衍射(XRD)、红外光谱(FTIR)、拉曼光谱(Raman)以及X射线光电子能谱(XPS)分析其结构和组成。采用紫外-可见光分光光度计检测石墨烯/Zn₂SnO₄催化降解亚甲基蓝(MB)性能。通过添加自由基捕获剂的光催化实验、电子顺磁共振谱和荧光光谱检测分析石墨烯/Zn₂SnO₄降解MB的光催化机理。通过光催化重复性实验对石墨烯/Zn₂SnO₄的稳定性进行评估。结果表明：加入石墨烯不会对Zn₂SnO₄的结构形貌产生较大影响;当氧化石墨烯(GO)添加量为4 Wt%时,石墨烯/Zn₂SnO₄的光催化活性最高的;光催化过程中·OH是主要的活性物质,存在·OH间接氧化有机污染物的机制。     

[PMo9V3O40]6-硫代物的合成及光谱研究

通过H2S与杂多化合物(NH4)4H2[PM 9V3O40]·10H2O在DMF中反应合成了其硫代产物,并对其进行了红外和拉曼光谱表征.     

球磨处理的TiO2光谱特征及其光催化性能研究

为改变TiO₂的颗粒尺寸和提高其光催化性能,采用高能球磨法处理TiO₂粉末,研究球磨时间对样品微观形貌、晶体结构、拉曼光谱、荧光光谱和光催化性能的影响;分析荧光光谱和光催化性能之间的关系,确定光催化机理为快速判断其光催化性能提供依据。结果表明：随着球磨时间的增加样品颗粒由规则形状变成无规则形状且表面变得粗糙。所有样品均主要为锐钛矿结构,有少量的金红石结构,随着球磨时间的增加金红石结构的(110)衍射峰逐渐增强说明在球磨过程中少量的TiO₂发生了相转变,晶粒尺寸先减小后增加。所有样品均出现锐钛矿型TiO₂拉曼散射峰,而未发现金红石晶型的拉曼散射峰。各个拉曼峰的半高宽随着球磨时间的增加都有所增加,这表明样品的表面质量下降,表面缺陷和氧空位逐渐增加导致。所有样品在470 nm附近均出现荧光峰,且球磨后的样品该荧光峰得到增强,经过球磨后的TiO₂样品在397, 452, 483, 500和536 nm等处出现荧光峰,且球磨4 h后的TiO₂荧光峰强度最强,表明其表...     

水热合成钛酸盐纳米管及其光催化性能研究

本文采用水热法制备了钛酸盐纳米管,并用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)和紫外-可见光谱(UV-VIS)对样品进行了分析。以罗丹明B溶液为目标降解物,考察了样品的光催化性能。结果表明纳米管管径在8～20纳米之间,管长从几百纳米到几微米,具有不同于锐钛矿的钛酸盐结构。在紫外光照射下,钛酸盐纳米管的光催化性能明显高于TiO2纳米粒子,光照100分钟后降解率达到87%。     

Synthesis, spectroscopy and antibacterial activity of supermolecular compounds of organotitanium substituted heteropolytungstates containing 8-quinolinol

Parent compounds of cyclopentadienyltitanium substituted heteropolytungstates with Keggin structure, An[(CpTi)XW11O39]· xH2O (A=Me4N, K; X=P, Si, Co; Cp=η5-C5H5) were synthesized in　aqueous phase. By allowing parent heteropoly compounds to react with protonated 8-quinolinol, he title　supermolecular compounds (C9H8NO)mAn[(CpTi)XW11O39] · xH2O (A=Me4N, H; X=P, Si, Co) were synthesized. The title compounds were characterized by means of elementary analysis, IR, UV, 1H NMR,XRD and TCG-DSC. The results indicate that the title compounds are new heteropoly compounds, and there is a charge transfer interaction between the organic cation and heteropoly anion. The results obtained from thermal analysis show that QCpTiPW, QCpTiSiW and QCpTiCoW begin to decompose at 212.4, 194. 2 and 171.2℃, respectively. The results obtained from antibacterial test reveal that QCpTiSiW has the best antibacterial activity, and the MIC values of QCpTiSiW against Escherichia coli and Staphylococcus aurous are 64. 0 and 0. 500 μg · mL-1 , respectively.     

Synthesis,spectral studies,and catalytic and antibacterial activity of Ru(II) complexes with coordinated amides

Twelve Ru(II) complexes with coordinated amides were synthesized and characterized by elemental, IR, ¹H, ¹³C, ³¹P NMR, mass, and electronic spectral analysis, along with magnetic and conductance measurements. Molecular formulas and octahedral structures have been tentatively proposed. These complexes were used as catalysts for the hydrolysis of rivastigmine and neostigmine. The hydrolyzed products were coupled with 3-methyl benzothiazolinone hydrazone reagent in the presence of sodium metaperiodate and the resulting colored products were determined spectrophotometrically. The yields of hydrolyzed products were found to be 98.47% and 99.75% respectively. All the ligands and Ru(II) complexes were screened for antibacterial activity. Published in Zhurnal Prikladnoi Spektroskopii, Vol. 75, No. 6, pp. 867–874, November–December, 2008.     

Synthesis and photocatalytic activity of porous polycrystalline NiO nanowires

Porous polycrystalline NiO nanowires were prepared via thermal decomposition of the nickelous precursor synthesized via the hydrothermal reaction of nickel chloride with trisodium citrate dehydrate (C₆H₅Na₃O₇⋅2H₂O) in ethanol–H₂O binary solution. The porous polycrystalline nanowires with the diameters of 350 to 450 nm were constructed from NiO nanocrsystals with the cubic structure and the sizes of 8 to 12 nm. The photocatalytic activity of the as-prepared porous NiO nanowires for the degradation of acid scarlet dye was studied. It was found that their photocatalytic activity was stronger than that of NiO powders.     

Synthesis,characterization, and biological activity of Schiff bases metal complexes

The new Schiff base 1‐[(2‐{1‐[(dicyclohexylamino)‐methyl]‐1H‐indol‐3‐yl}‐ethylimino)‐methyl]naphthalen‐2‐ol (HL) was prepared from 1‐{[2‐(1H‐Indol‐3‐yl)‐ethylimino] methyl}‐naphthalen‐2‐ol and dicyclohexyl amine. From this Schiff base, monomeric complexes [M (L)_n (H₂O)₂ Cl₂] with M = Cr, Fe, Mn, Cd, and Hg were synthesized and characterized based on elemental analysis (EA), FT‐IR, mass(MS), UV‐visible, thermal analysis, magnetic moment, and molar conductance. The results showed that the geometrical structural were octahedral geometries for the Cr(III) and Fe(III) complexes, square planer for Pd(II) complex, and tetrahedral for Mn(II), Cd(II), and Hg(II) complexes. Kinetic parameters such as ΔE*,ΔH*, ΔG*, and K of the thermal decomposition stages were calculated from the TGA curves using Coats‐Redfern method. Additionally, density functional theory (DFT) was applied for calculations of both electronic structure and spectroscopic properties of synthesized Schiff base and its complexes. The analysis of electrostatic potential (EPS) maps correlates well with the computed energies providing on the dominant electrostatic nature of N‐H‐‐‐O interactions. The biological activities had been tested in vitro against Staphylococcus aureus, Pseudomonas aeruginosa, as well fungi like Penicillium expansum, Fusarium graminearum, Macrophomina phasealina, and Candida albicans bacteria in order to assess their antimicrobial potential.     

镉掺杂氧化锌纳米花的制备及其光催化活性

以氯化锌、氯化镉、氢氧化钠为原料,采用水热法合成Cd掺杂纳米花状ZnO光催化剂,并通过该样品对罗丹明B水溶液的降解来研究其光催化活性。利用X射线衍射（XRD）、扫描电子显微镜（SEM）、X射线能量色散谱（EDS）、光致发光谱（PL）及紫外-可见分光光度计（UV-Vis）等测试手段对材料物性进行表征。实验结果表明：当掺杂Cd²⁺时,样品形貌发生变化、粒径减小;掺杂Cd²⁺后的ZnO的吸收边和紫外峰对比于纯ZnO均发生红移,禁带宽度由3.24 eV 减小到3.16 eV。通过光催化实验分析可知,掺杂后纳米ZnO光催化剂对罗丹明B 水溶液的降解率有所提高,光照3 h其降解率高达98%,说明与纯ZnO相比,Cd掺杂ZnO纳米花具有更高的光催化活性。     

Charge transfer-transitions and X-ray photoelectron spectroscopy of copper(II) complexes

Satellite structure in the X-ray photoelectron (Cu 2p) spectra of some squareplanar cupric complexes has been compared to electron paramagnetic resonance and electronic spectra results on the electronic structure of these complexes. It is shown that these satellites can be assigned to various ligand → metal 3d or ligand → ligand* transitions within the monopole selection rules of the sudden approximation.     

Synthesis of Zr-doped TiO2 templated from cloth and its photocatalytic activity

Biomorphic Zr-doped TiO₂ (Zr _x Ti_{1 ? x} O₂) with hierarchical micro- and nanostructures was successfully fabricated using cloth as the host template. We found that the resulting Zr _x Ti_{1 ? x} O₂ faithfully duplicated the morphologic microstructures of the initial cloth with grain size of about 10–50 nm. The photocatalytic activity of the as-prepared Zr _x Ti_{1 ? x} O₂ was examined by the degradation of rhodamine B in aqueous solution under simulated solar light, which showed that templates pretreated with NaOH solution followed by mixed acid and an appropriate amount of doped Zr (3 mol%) could significantly enhance the photocatalytic activities of Zr _x Ti_{1 ? x} O₂. This simple template method provides a cost-effective and ecofriendly route to synthesize other metal-doped semiconductor materials of predicted morphology.     

Synthesis,characterization and excellent photocatalytic activity of Ag/AgBr/MoO3 composite photocatalyst

A novel composite photocatalyst Ag/AgBr/MoO₃ was successfully synthesized via a simple precipitation method at room temperature. The obtained products were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, high-resolution transmission electron microscopy and UV–vis diffuse reflectance spectroscopy in detail. The photocatalytic activity of the samples was evaluated by monitoring the degradation of rhodamine B (RhB) solution under visible-light irradiation. The results showed that the photocatalytic activity of Ag/AgBr/MoO₃ composite significantly enhanced and the degradation ratio of RhB reached 97.7 % after 15 min only. The excellent photocatalytic activity might be closely related to the large surface area, porosity structure and efficient separation of photoinduced electron–hole pairs. The possible reaction mechanism was also discussed.     

Graphene-CdS composite, synthesis and enhanced photocatalytic activity

Graphene-CdS (G-CdS) composites were synthesized through a simple solvothermal method. The formed CdS nanospheres were homogeneously scattered on the surface of graphene sheets. Fluorescence quenching effect of the G-CdS composites indicated effective transfer of photo-excited electrons from CdS to graphene, suppressed the recombination of photo-generated electron-hole pairs, so that the enhanced visible light induced photodegradation activity for Rhodamine B (RhB) was achieved. Based on the high photocatalytic activity and well stability, the G-CdS composite containing 70% CdS can be expected to be a practical visible light photocatalyst.