两亲分子结构对铜网表面生长的Cu2S纳米材料形貌的影响

观察到两亲分子的结构对铜网表面生长的Cu2S-维纳米材料的形貌有较大的影响，含羧酸的强亲水型两亲分子——N-硬脂酰-L-谷氨酸有助于形成纳米线，而把两个羧基全部转化为酯基后．则倾向于形成具有分形结构的纳米带。     

基于Cu2S电阻开关器件的光电记忆效应

硫化亚铜由于其独特的电和光学特性,被广泛应用于电阻开关存储和光伏器件.本文通过脉冲激光沉积/化学气相沉积两步法合成Cu₂S薄膜,该膜由纳米颗粒构成,结晶度高,在近红外区有较好的光吸收特性.蒸镀铜电极构成Cu/Cu₂S/P-Si结构忆阻器件后,器件表现出电子型双极阻变行为,其阻变机制由空间电荷限制电流和肖特基发射机制协同主导.此外,还探究了光对器件阻变行为的响应及机理.结果表明,在光照下,最大电流响应增加至暗态时的5倍.分析认为,光照使Cu/Cu₂S界面处的肖特基势垒减小,在高阻态下,阻变机制由肖特基发射机制转变为空间电荷限制电流机制,并使器件电导率增加.本工作为Cu₂S基光电协同响应忆阻器的研发提供了新思路.     

囊泡的形成与两亲分子结构

本文综述了可以形成囊泡的各类两亲分子的结构特点和形成条件，并对某些体系中囊泡的形成机理进行了探讨。     

含席夫碱的噻吩两亲分子表面活性剂的合成

在氯化亚砜存在下,2,5-二甲酸噻吩与甲醇反应得到2,5-二甲酸甲酯噻吩(1),1与水合肼反应得对应的噻吩酰肼(2),2再与辛酮缩合得到含席夫碱的噻吩两亲分子表面活性剂,其结构经1H NMR,IR和元素分析确认。     

两亲聚合物表面的反相气相色谱分析

采用反相气相色谱探针技术研究了苯乙烯－氧乙烯－苯乙烯三嵌段两亲聚合物的表面物理化学性质。包括表面吸附热力学函数,表面能的色散分量以及表面分子链与探针的分子间相互作用,。探讨了共聚物中亲油性链段聚苯乙烯（PS）和亲水性链段聚氧乙烯（PEO）的组成比例与其表面性质的关系。结果表明共聚物表面组成中随PEO含量的增加,其表面能增大,表面分子链与探针分子的相互作用增强,表面吸附能力也增强。     

不同表面形貌Cu2O空心球的制备及光催化性能

采用一步溶剂热法,以Cu(NO_3)_2·3H_2O为铜源,乙二醇(EG)为还原剂,聚乙烯吡咯烷酮(PVP)为表面活性剂,高温条件下制备形貌可控的Cu_2O空心球纳米材料。研究Cu(NO_3)_2·3H_2O与PVP的质量比值(w_(Cu(NO_3)_2·3H_2O)/w_(PVP))对Cu2O结构、形貌、比表面积以及光吸收特性的影响,并结合光催化机理讨论其对Cu_2O光催化性能的影响。此外,通过改变反应时间来研究Cu_2O的生长过程。结果表明,w_(Cu(NO_3)_2·3H_2O)/w_(PVP)=45时,得到的形貌为空心球表面覆盖纳米刺的Cu_2O纳米材料光催化性能最佳,在可见光辐照10 min的条件下,对甲基橙的降解率达94.3%。     

两亲嵌段树枝状分子Gx-PBE-b-Gx-PMPA(OH)x2的合成及多重氢键作用

合成了1~3代的嵌段树枝状分子聚苄醚-聚脂肪酯(Gx-PBE-b-Gx-PMPA, x=1,2,3)和两亲嵌段树枝状分子聚苄醚-周边含羟基的聚脂肪酯[Gx-PBE-b-Gx-PMPA(OH)x2, x=1,2,3]. PMPA(OH)x2-树枝片(Dendron)段周边的羟基数目分别是2, 4和8. 通过1H NMR, 13C NMR, FTIR和基质辅助激光解吸附电离飞行时间质谱(MALDI-TOF)(或场解析电离质谱)技术表征了Gx-PBE-b-Gx-PMPA和Gx-PBE-b-Gx-PMPA(OH)x2的结构. 同时, 采用变温FTIR光谱研究了在两亲嵌段树枝状分子中形成的氢键模式. 结果表明, 随着树枝片代数的增加, 两亲嵌段树枝状分子内趋向于形成作用较弱的分子内氢键, 说明形成3代两亲嵌段树枝状分子的三维结构削弱了羟基形成分子间氢键的能力.     

松香基甜菜碱两亲分子构筑多维Ni(OH)2/NiOOH微纳米复合材料

采用自制脱氢松香基甜菜碱功能性两亲分子构筑得到3种形貌均匀的Ni(OH)₂/NiOOH微纳米复合材料, 分别为孔径约2 μm的三维珊瑚状、花状空心微球和宽度约100 nm的二维纳米片, 对复合材料的物相组成和形貌结构采用X射线衍射(XRD)、扫描电镜(SEM)和透射电镜(TEM)等技术手段分析表征。结合自制松香基甜菜碱两亲分子红外光谱(FT-IR)、核磁(NMR)结构表征和优异的表面活性推测得到松香基甜菜碱两亲分子构筑3种不同形貌微纳米复合材料的机理;研究表明, 在松香基甜菜碱两亲分子稳定刚性结构的作用下, 通过反应温度控制其吸附能力可构筑出3种形貌分散性较好的氢氧化镍复合材料。     

松香基甜菜碱两亲分子构筑多维Ni(OH)2/NiOOH微纳米复合材料

采用自制脱氢松香基甜菜碱功能性两亲分子构筑得到3种形貌均匀的Ni(OH)_2/NiOOH微纳米复合材料,分别为孔径约2μm的三维珊瑚状、花状空心微球和宽度约100 nm的二维纳米片,对复合材料的物相组成和形貌结构采用X射线衍射(XRD)、扫描电镜(SEM)和透射电镜(TEM)等技术手段分析表征。结合自制松香基甜菜碱两亲分子红外光谱(FT-IR)、核磁(NMR)结构表征和优异的表面活性推测得到松香基甜菜碱两亲分子构筑3种不同形貌微纳米复合材料的机理;研究表明,在松香基甜菜碱两亲分子稳定刚性结构的作用下,通过反应温度控制其吸附能力可构筑出3种形貌分散性较好的氢氧化镍复合材料。     

反应溶剂对Bi2S3粉体形貌的影响

利用溶剂热法在不同反应溶剂中制备了不同尺寸的Bi2S3纳米管和纳米棒.利用XRD、SEM、TEM、选区电子衍射(SAED)和高分辨透射电镜(HRTEM)对其结构和形貌进行了表征.结果表明,所制备的产物是结晶良好的正交相Bi2S3,反应溶剂的表面张力、粘度大小和反应溶剂中的比例影响纳米粉体的形貌和尺寸.紫外-可见光吸收光谱测量表明,由于尺寸效应所有粉体的吸收谱相对于正交相的Bi2S3块体都出现蓝移.     

Molecular Recognition Based on Hydrogen-bonding in the Coliposomes of Phosphatidylcholine and Amphiphiles Using Nucleobases

IntroductionMolecular recognition is an essential phenomenonin living systems, as observed in the formation of com-plementary hydrogen bonds in DNA[1]. It is interestingto know whether more primitive structures containingthe same bases as thatof DNAor RNA…     

Measurements of H2S in the Atmosphere

Swamps and tidal flats are believed to he important natural sources of atmospheric H₂S, though it is very difficult to detect the low concentrations of this trace gas above the surface of these regions. In view of this problem an air sampling device has been developed for the sampling of atmospheric H₂S with chemically impregnated filters. The sulfide generated on the filter is analyzed in a washing solution employing a very sensitive fluorescence method. The quality of the method is demonstrated by comparative calibrations. The fluorescence method is calibrated in the liquid phase with standard solutions of sulfide. Furthermore the sampling and analyzing method is calibrated together by using H₂S calibration gases. The detection limit of the method is shown to he 10ng/m³ STP. Data of test-measurements in ambient air and some results of field-measurements in the lower troposphere are presented.     

Mo-Doped Cu2S Multilayer Nanosheets Grown In Situ on Copper Foam for Efficient Hydrogen Evolution Reaction

Metal sulfide electrocatalyst is developed as a cost-effective and promising candidate for hydrogen evolution reaction (HER). In this work, we report a novel Mo-doped Cu₂S self-supported electrocatalyst grown in situ on three-dimensional copper foam via a facile sulfurization treatment method. Interestingly, Mo-Cu₂S nanosheet structure increases the electrochemically active area, and the large fleecy multilayer flower structure assembled by small nanosheet facilitates the flow of electrolyte in and out. More broadly, the introduction of Mo can adjust the electronic structure, significantly increase the volmer step rate, and accelerate the reaction kinetics. As compared to the pure Cu₂S self-supported electrocatalyst, the Mo-Cu₂S/CF show much better alkaline HER performance with lower overpotential (18 mV at 10 mA cm⁻², 322 mV at 100 mA cm⁻²) and long-term durability. Our work constructs a novel copper based in-situ metal sulfide electrocatalysts and provides a new idea to adjust the morphology and electronic structure by doping for promoting HER performance.     

On the Crystal Structure of K2Cu5Cl8(OH)4·2H2O

Single crystals of K₂Cu₅Cl₈(OH)₄·2H₂O were grown using hydrothermal techniques. The compound is monoclinic with a = 11.6424(11), b = 6.5639(4), c = 11.7710(10)Å, β = 91.09(1)°, V = 899.4(2)ų, space group P2₁/c, Z = 2. The crystal structure was determined using single crystal X‐ray diffraction data and refined to a residual of R(|F|) = 0.025 for 1208 independent observed reflections with I > 2σ(I). Two out of three crystallographically independent Cu atoms are coordinated to four near hydroxyl groups or chlorine atoms and two more distant Cl atoms, giving an octahedrally Jahn‐Teller distorted (4+2)‐configuration. For the remaining third copper cation a square‐planar coordination can be found. Edge‐sharing of the octahedra results in the formation of kagome‐type sheets parallel to (100). The octahedral layers are decorated on both sides by planar [Cu(OH)₂Cl₂]‐units around the third Cu atom. The K atoms are located between adjacent sheets and are surrounded by six Cl atoms as well as two water molecules. The coordination polyhedra about the K‐atoms can be described as distorted bicapped trigonal prisms. Additional linkage is provided by intra‐ as well as inter‐layer hydrogen bonds (O—H···Cl, O—H···O).     

The Crystal Structure of Ba2Cu2AlF11: a New Structure Type in Copper Fluoride Crystal Chemistry

Ba₂Cu₂AlF₁₁ is trigonal: a = 7.301(1) Å, c = 14.145(2) Å, γ = 120°, Z = 3. The crystal structure was solved in the space group P3₂ (n° 145), from X-ray single crystal data using 2675 unique reflections (2476 with F/σ(F) > 4). It consists in a complex tridimensional arrangement of copper-fluorine and aluminium-fluorine octahedra, with an original kind of linkage which involves simultaneously edges and vertices.     

泡沫铜负载硫化亚铜电极高效电催化还原二氧化碳制备甲酸

电催化还原二氧化碳制备甲酸是备受关注的热点问题。而电极材料是决定还原效率的重要因素。本文通过电沉积方法在泡沫铜上直接制备纳米结构硫化亚铜薄膜,并采用扫描电镜(SEM)、X射线衍射(XRD)对其结构性能进行了系统研究。以硫化亚铜作为阴极电催化材料、0.5 mol·L^-1 1-丁基-3-甲基咪唑四氟硼酸盐的乙腈溶液为电解液,在该体系中可高效催化转化二氧化碳为甲酸。结果表明,这一电解体系可有效实现电化学反应,甲酸的法拉第效率(FE_HCOOH)可以达到85%,同时甲酸还原电流密度可达到5.3 mA·cm^-2。     

Controllable Synthesis and Study on Morphology of Copper Nanowires

High‐purity, large‐aspect‐ratio, and well‐dispersed copper nanowires (CuNWs) with an average diameter of 45 nm and length >100 μm were successfully synthesized by reducing a Cu(II) salt with glucose, with oleylamine (OM) and oleic acid (OA) serving as dual capping agents, through hydrothermal reduction. A systematic study of the effects of the copper salt, capping agents, reductant, and temperature on the morphology of CuNWs has been conducted. Our results indicate that CuNWs with different diameters can be obtained using different copper salts. The diameter of the as‐prepared CuNWs decreases with increasing amounts of OM/OA and glucose but increases with the increasing temperature of the reaction. By adjusting the experimental parameters, we could achieve controlled synthesis of CuNWs and obtain high‐quality CuNWs with different diameters of 45, 76, 85, 90, 100, 112, 135, and 175 nm.     

纳米多级结构枣核型多孔氧化亚铜的合成及拉曼性质

通过简单温和的水相还原反应, 在表面活性剂十二烷基苯磺酸钠(SDBS)的协同下合成了亚微米级枣核型多孔氧化亚铜纳米多级结构. 通过改变盐酸的加入量可以实现纳米粒子尺寸在300-900 nm范围可调. X射线衍射(XRD)和透射电子显微镜(TEM)分析表明, 亚微米粒子由小于10 nm的晶粒构成. 基于实验结果, 我们提出生长-刻蚀竞争生长模型来解释枣核型空心多孔结构的形成机制, 同时说明了尺寸调节机理. 利用激光拉曼光谱仪研究了样品的光学性质, 与相似尺寸的亚微米实心多面体的拉曼响应信号对比发现, 枣核型空心多孔结构的拉曼光谱表现出新颖的特性. 这些结果补充了氧化亚铜的拉曼光谱样本, 对文物表面颜料的无损拉曼检测具有一定的指导意义.     

Structure and magnetic properties of a double out-of-plane carboxylato-bridged Cu(II) compound with pyridine-2-carboxylate

The spectroscopic and magnetic properties, and crystal structure of dark-blue [Cu(2-pca)₂]_n (1), (2-pca = pyridine-2-carboxylate ion) are described. The copper(II) ions are in strongly tetragonally distorted octahedral environments. They are sequentially bridged by a double out-of-plane carboxylate bridge, resulting in the formation of an infinite chain (1D). The equatorial Cu–O bonds (1.957(3) Å) are significantly shorter than the axial bonds (2.737(4) Å). The crystal structure of the compound is stabilized by interchain hydrogen bonds of the C–H?O type. The intrachain copper–copper separation is 5.178(3) Å, whereas the shortest interchain copper–copper distance is 7.614(6) Å. The magnetic properties, investigated in the temperature range 1.8–300 K, revealed the occurrence of a weak intrachain antiferromagnetic coupling, J = −1.04 cm⁻¹, and an interchain exchange interaction, zJ′ = 0.34 cm⁻¹. The title compound appears to be a polymorphic form of the blue-violet compound (2) of identical stoichiometry, the X-ray structure of which was recently reported. Magneto-structural correlations in 1 have been made considering both the carboxylato bridging group and the existence of interchain hydrogen bonds. The structure and magnetic properties of 1 are compared with those of the polymorphic form 2.