The effect of PbS nanoparticles on the formation of PbSe in aqueous solutions of sodium selenosulfate and lead(II)

It was established that PbS nanoparticles significantly increase the rate of formation of lead selenide during the reaction of Pb(NO₃)₂ and Na₂SeSO₃ in aqueous solutions of polymers. It was shown that the reaction product consists of PbS/PbSe nanoparticles with a “PbS core-PbSe shell” structure. A correlation was found between the forbidden band widths of the PbS nanoparticles and the PbS/PbSe nanostructures formed during the reaction. __________ Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 42, No. 6, pp. 339–344, November–December, 2006.     

A facile approach to the preparation of loose-packed Ni(OH)2 nanoflake materials for electrochemical capacitors

Loose-packed nickel hydroxides were successfully synthesized by a facile chemical precipitation method. Structure characterizations indicate that a nanoflake structure with low crystallinity for the nickel hydroxide samples was obtained. Electrochemical studies were carried out using cyclic voltammetry, chronopotentiometry technology, and alternating current impedance spectroscopy, respectively. A maximum specific capacitance of 2,055F/g could be achieved in 2M aqueous KOH with the potential range of 0 to 0.4V (vs. the saturated calomel electrode) in a half-cell setup configuration for the nanoflake Ni(OH)₂ electrode, suggesting its potential application in the electrode material for electrochemical capacitors. Furthermore, the effect of annealing temperatures on the electrochemical capacitance characteristics has also been systemically explored.     

Ligand-structure effect on electrochemical reduction of copper(II) complexes

Summary Half-wave potentials for a one-electron reduction of copper(II) complexes containing polydentate ligands can be calculated using the equationE _1/2=E ⁰(Cu^2+/+)+ _{i j} E _i where E _i are contributions related to the electronic and steric properties of the ligands. The values of 18 E _i contributions are presented and explained, and the effect of the solvents on the half-wave potentials is exemplified.Dedicated to Prof. Dr. Viktor Gutmann to his 70th birthday     

Substrate assisted electrochemical deposition of patterned cobalt thin films

The patterned Co layers deposited on the scratched Cu surfaces were investigated with the use of the scanning electron microscopy. Patterned cobalt thin films were electrochemically deposited from the cobalt sulfate bath at room temperature. Pattering of cobalt was carried out by simple means of substrate scratching. Gentle scratching induces a direct pattering of cobalt from vertical to horizontal. The prepared pattered films were characterized for their structural, surface morphological and compositional properties by means of X-ray diffraction, scanning electron microscopy and energy dispersive spectroscopy. X-ray diffraction studies reveal that the films are of cobalt. From the SEM images fabrication of patterns of cobalt is apparent. This work demonstrates a novel approach for obtaining patterned cobalt for many technological applications.     

Polymeric nanocomposite materials: Preparation and characterization of star-shaped PbS nanocrystals and their influence on the thermal stability of acrylonitrile-butadiene-styrene (ABS) copolymer

Star-shaped PbS nanocrystals were synthesized via a simple hydrothermal reaction between Pb(NO₃)₂·4H₂O and thioglycolic acid at a relatively low temperature. The PbS nanostructures were then combined in a acrylonitrile-butadiene-styrene copolymer. The effect of the PbS nanostructures on the thermal stability of the nanocomposite products has been investigated. The nanostructures and nanocomposite were characterized by X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectra, thermogravimetric-differential thermal analysis and atomic force microscopy. Cone calorimeter measurements showed that the heat release rate significantly decreased in the presence of PbS.     

用软刻蚀方法制备PbS纳米晶复合聚丙烯酸微图形

PbS microstructures have several applications such as Pb2+ion-selective sensors and IR detector.The method to prepare PbS nanocrystal embed in poly(acrylicacid) (PAA) microstructures produced by means of soft lithography and solid state polymerizatio n by γ-ray irradiation was described. PbS micro patterns were prepared by Micro molding in Capillaries (MIMIC) with aqueous solution of acrylic acid lead monomer, and then solid state polymerized by γ-ray irradiation. Finally, the sample was treated with aqueous solution of Na2 Stoconvert the Pb2+ to PbS in the matrix. High-resolution micro structures of PAA, which have PbS nanocrystals embedded in them, could be produced successfully in this way. The final products were characterized by TEM, XRD, and XPS. TEM image indicated that the PbS particles embedded in PAA had a diameter of smaller than 20nm. X-ray powder diffraction method was also used to characterize the PbS/PAA nanocomposite film. The XPS analysis showed the element Pb has been converted to PbS nanoparticles in the composite films.     

聚合物对硫化铅钠米微粒的稳定作用

以含铅聚合物微凝胶与Ｈ２Ｓ气体反应制得ＰｂＳ纳米微粒／聚合物复合体系，利用小角Ｘ光散射方法对复合在聚合物中的ＰｂＳ纳米微粒的粒度及分布进行了表征，研究了不同反应条件对其粒度及复合体系稳定性的影响。     

氯化介质中PbS固体表面的氯络合-溶解行为

对硫化铅固体表面的氯络合-溶解行为进行了研究。溶液化学计算考察颗粒表面固体反应产物(PbCl2)的生成与溶解情况表明,饱和氯化钠介质中PbCl2主要以[PbCl4]2-络合物的形式存在于溶液中,氯离子组分总浓度[Cl-]T=0·918mol/L时,PbCl2能较好地呈固态晶体析出,[Cl-]T>0·918mol/L时PbCl2晶粒因氯络合作用而溶解。通过Tafel实验进一步分析了PbS固体表面的腐蚀溶解行为,结果显示,当CFe3 ≤6×10-4mol/L时,腐蚀速度对Fe3 存在很强的依数性,浓度增加,腐蚀速度快速提高;CFe3 >6×10-4mol/L,有钝化现象发生。NaCl的加入,溶液相Cl-活度增加,PbCl2快速溶解,腐蚀反应加快。     

PbS纳米微粒对溴化银微晶乳剂的化学增感作用

发现了PbS纳米微粒对溴化银乳剂的化学增感作用,对PbS和Na₂S₂O₃对卤化银乳剂的增感作用进行了比较,研究了增感剂用量、增感温度和pAg值、溴化银的晶型等因素的影响,以及PbS纳米微粒与HAuCl₄的协同增感效应.     

W/O型微乳液中不同形貌PbS纳米粒子的制备及其形成机理的探讨

用聚乙二醇辛基苯基醚(OP)/异辛醇/环己烷/水溶液所形成的微乳液体系控制合成出了PbS纳米粒子，考察了微乳液中水与表面活性剂的物质的量的比(ω₀)、反应物浓度及浓度比、陈化时间等条件对产物形貌的影响。采用透射电子显微镜(TEM)、X-射线衍射(XRD)分别对产物的结构、粒度和形貌进行了表征。结果表明，在微乳液体系中，控制不同的实验条件，可以成功地合成球形、梭形、针状和棒状的PbS纳米粒子，并且粒径分布集中，无团聚现象。论文还对不同形貌PbS纳米粒子的形成机理进行了探讨。     

Effect of Some Metal Ion Dopants on Electrochemical Properties of Ni （OH）2 Film Electrode

The Ni(OH)2 film electrodes doped respectively with alkali-earth metals aluminum, lead, partial transi-tion metal and some rare-earth metal (altogether 17 kinds of metals) ions were prepared by cathode electrode-position. The electrode reaction reversibility, the difficult extent of oxygen evolution, the proton diffusion coefficient, the discharge potential of middle value and the active material utilization of the Ni(OH)2 film elec-trode were compared with those of the ones doped with the metal ions by means of cyclic voltammetry, poten-tial step and constant current charge-discharge experiments. It was found that Ca^2 , Co^2 , Cd^2 , Al^3 etc. have obviously nositive effect.     

Influence of the Host Matrix on the Microstructure of Sol-Gel Films Doped with CdS and PbS Q-Dots

The preparation of non-linear optical materials for integrated photonic devices needs the development of procedures which permit a very good control of the microstructure. Sol-gel is a good method for the preparation of glasses doped with semiconductor Q-Dots. However, the control on the microstructure and the properties of the material is related to many parameters (e.g., conditions of hydrolysis, precursors, heat treatments, etc.). In this work the effect of the matrix on the size and size distribution of the semiconductor nanoparticles was investigated. The films were characterized by UV-VIS-NIR spectrophotometry, Grazing Angle X-Ray Diffraction (GA-XRD), and High Resolution Transmission Electron Microscopy (HRTEM).     

金属基上以YSZ为过渡层的YBCO薄膜的微观结构

采用透射电子显微术（ＴＥＭ），研究了用磁控溅射技术在柔性金属基体上制备的、钇稳定的ＺｒＯ２（ＹＳＺ）为过镀层的ＹＢａ２Ｃｕ３Ｏ７－ｙ（ＹＢＣＯ）薄膜的横断面结构。所得ＹＢＣＯ膜的超导临界转变温度Ｔｃ为９１Ｋ，临界电流密度Ｊｃ＝２×１０３Ａ／ｃｍ２（７７Ｋ，０Ｔ）。基体为Ｎｉ基合金（ＨａｓｔｅｌｏｙＣ）。ＹＳＺ层为致密、均匀的细晶组织，约１２μｍ厚，具有织构取向，并与基体紧密连接。ＹＢＣＯ层的厚度不均匀，约５００ｎｍ；ＹＢＣＯ／ＹＳＺ界面有时连接较差，在该界面上有杂质出现，杂质有可能引发裂纹。     

Influence of cation (NH 4 + ) on electrochemical characteristics of MnO2 nanowire synthesized by hydrothermal method

Nanowires of MnO₂ were prepared by a simple method in which the commercial granular -MnO₂ powders were hydrothermally treated in water or ammonia solution at 150 °C. These 1D nanostructured manganese oxides were characterized physically by X-ray diffraction, scanning electron microscopy and transmission electron microscopy tests. Cyclic voltammetry and constant current discharge experiments were employed to explore the diversity of electrochemical performances; and the reasons for the difference are discussed. The experimental results indicate that the existence of NH₄⁺ in the preparation solution has depressed the electrochemical performances of the final product; This is further confirmed by the electrochemical impedance spectra of the electrodes.     

Synthesis of novel ferrocene containing vic-dioxime ligands and their Ni(II), Cu(II) and Co(II) complexes: Spectral, electrochemical and biological activity studies

Two new vic-dioxime ligands bearing an important redox-active substituent, anti-β-ferrocenylethylaminoglyoxime (1a) and anti-β-ferrocenylethylaminophenylglyoxime (1b), have been synthesized, and their Ni(II), Cu(II) and Co(II) (2a-4a, 2b-4b) complexes were obtained. The composition and structure of the products were determined by elemental analysis, Fourier transform infrared (FT-IR), ultraviolet-visible (UV-vis), mass spectrometry (MS), one-dimensional (1D) ¹H, ¹³C NMR, and two-dimensional (2D) heteronuclear multiple bond correlation (HMBC) techniques. The redox behaviors of the ligands and their complexes were investigated by cyclic voltammetry (CV), which revealed that all the ferrocenyl redox centers are electrochemically independent and undergo a quasi-reversible oxidation at similar potentials. Also, antibacterial activity was studied against Staphylococcus aureus ATCC 29213, Streptococcus mutans RSHM 676, Enterococcus faecalis ATCC 29212, Escherichia coli ATCC 25922 and Pseudomonas aeruginosa ATCC 27853. The antimicrobial test results indicated that all the compounds have mild levels of antibacterial activity against both gram negative and gram-positive bacterial species.     

The effect of preanodization on the electrochemical detection of oprenolol in plasma

Summary Modification of the electrode surface by pre-anodization of glassy carbon electrodes causes a significant increase in sensitivity for the detection of oxprenolol. This method was used in conjunction with HPLC to measure the concentration of oxprenolol in samples of plasma and the results compared with those obtained by the established electron-capture GC method. The resulting values showed a good correlation between the methods and indicate that pre-anodization is a practical means for the enhancement of electrochemical detector sensitivity.     

基于PbS量子点和金纳米颗粒的可卡因适体传感器的研究

本文采用水热法合成了硫化铅量子点,将其与壳聚糖混合后修饰在玻碳电极上,利用PbS与巯基之间的强烈的键和作用,直接将所合成的带巯基的与可卡因适体互补的DNA固定到电极上,将金纳米颗粒标记在可卡因适体作为示踪物检测可卡因,研制了一种新型的用于快速测定可卡因的适体传感器.该适体传感器与不同浓度的可卡因培育时,可卡因适体与可卡...     

活性炭二次活化对其电化学容量的影响

为进一步提高作为电化学超级电容器电极材料活性炭的电化学容量, 采用KOH作为二次活性剂, 将所得活性炭进行二次化学活化处理, 从而得到二次活化活性炭. 将原始活性炭材料与二次活化活性炭材料都分别经过系列处理, 组装成电化学超级电容器进行电化学性能测试. 测试结果表明, 二次活化活性炭材料的电化学容量达到145.0 F·g-1(有机电解液), 远远大于原活性炭材料的容量(45.0 F·g-1). 为研究二次活化活性炭材料电化学容量大幅提高的原因, 将这两种材料分别进行微观结构数据测试, 包括比表面积、N2吸脱附等温曲线和孔径分布. 研究结果表明, 二次活化处理大大增加了二次活化活性炭材料在孔径为2-3 nm的中孔分布, 从而证实对于有机电解液, 电极材料在2-3 nm的中孔对其电化学容量的提高具有重要意义.     

Electrochemical synthesis and crystal structure of cobalt(II), nickel(II), copper(II), zinc(II) and cadmium(II) complexes with 2-pyridinecarbaldehyde-(2′-aminosulfonylbenzoyl)hydrazone

A new hydrazonic Schiff base ligand, 2-pyridinecarbaldehyde-(2′-aminosulfonylbenzoyl)hydrazone (HL), has been prepared and characterized, and its coordinative properties were studied. [ML₂] complexes, M = Co, Ni, Cu, Zn or Cd have been synthesised by electrochemical oxidation of the anodic metal in a cell containing an acetonitrile solution of the ligand. The compounds obtained have been characterized by microanalysis, IR, NMR and UV–Vis spectroscopy, mass spectrometry and also by X-ray diffraction. The structural studies show that the metal is in a distorted octahedral environment with the monoanionic ligand acting as a meridional tridentate (N,N,O) chelate system.