芳香性团簇的结构和光谱性质的理论研究

对近年来芳香性团簇的理论研究进行了总结，主要集中在以铝原子为主的芳香性团簇、磷属元素团簇、硼原子系列团簇以及夹层型配合物和笼型分子团簇等方面，展示了该领域的一些重要研究进展和应用前景。     

NMAP夹层抑制锂硫电池穿梭效应

利用水热合成法制备纳米NiO与多壁碳纳米管(MWCNTs)以及芳纶纸(AP)制备出一种新型复合夹层(NMAP)。NMAP夹层具有三维多孔结构,不但减小了活性物质的损失,还可以捕获可溶性多硫化物;NMAP夹层具有较强的化学吸附聚硫化物的能力。利用透射电子显微镜(TEM)、扫描电镜(SEM)、X射线衍射(XRD)等对复合夹层进行结构和性能的表征。电化学测试结果表明,NMAP夹层高性能锂硫电池在0.05C倍率下首次放电比容量达到1437 mAh·g^-1,活性物质的利用率高达85.8%;在4C大倍率下放电比容量仍然达到668 mAh·g^-1,且库伦效率仍然保持在99.1%;显示出良好的倍率和循环性能。     

稳定的ZrO2基SOFC中CeO2夹层的制备方法和作用机制

Sm、Gd和Y掺杂的CeO₂夹层是解决固体氧化物燃料电池的电极和电解质间物理化学性质不相容问题的最佳材料，已经展示出广泛的应用前景。本文介绍了CeO₂粉体的各种合成方法以及对粉体性能的影响。综述了制备CeO₂夹层薄膜的各种方法，其中包括直流反应磁控溅射（Reactively direct current magnetron sputtering）物理方法；火焰辅助气相沉积（Flame assisted vapor deposition，FAVD）和溶胶凝胶法（Sol-gel）等化学方法；电泳沉积法（Electrophoretic deposition, EPD）、丝网印刷法（Screen printing）和浸渍涂布法（dipping deposition）等陶瓷成型方法，评述了这些方法的优缺点，详细介绍了近年来采用上述方法制备的CeO₂夹层薄膜的性能以及对电池性能的改进，论述了CeO₂夹层提高电池性能的作用机制。综合分析了这些制备方法的异同和特点，指明了该领域的发展前景。阐述了开展CeO₂夹层研究对我国SOFC发展的重大意义。     

碳膜夹层锂硫电池的电化学性能

选取Super-P（SP）、KB或MWCNTs导电碳膜夹层,并置于硫电极与隔膜间组装成扣式锂硫电池.相关评估结果表明,碳膜夹层可显著提高锂硫电池循环性能,硫电极（载硫量为80%,by mass,下同）循环40周后比容量均在800 mAh·g^-1以上. 上述三种碳膜的物理性质有较大差异,导致相应电池具有不同电性能. KB碳膜夹层电池呈现较强的电化学极化效应;SP碳膜夹层电池循环初期可释放出最高的比容量,而循环稳定性较差;MWCNTs碳膜可视为较适宜的导电碳夹层材料.     

石墨烯及其复合材料在锂离子电池中的应用

石墨烯是一种单原子层厚度的石墨材料,具有独特的二维结构和优异的电学、力学以及热学性能。同时它也是一种具有良好应用前景的锂离子电池电极材料。电极材料的微观结构对其性能有很大影响,利用石墨烯获得具有特殊形貌和微观结构的电极材料,能有效改善材料的各项电化学性能。本文综述了石墨烯及其复合材料在锂离子电池中的应用研究进展。在负极复合材料中,石墨烯不仅可以缓冲材料在充放电过程中的体积效应,还可以形成导电网络提升复合材料的导电性能,提高材料的倍率性能和循环寿命。通过优化复合材料的微观结构,例如夹层结构或石墨烯片层包覆结构,可进一步提高材料的电化学性能。在正极复合材料中,石墨烯形成的连续三维导电网络可有效提高复合材料的电子及离子传输能力。此外,相比于传统导电添加剂,石墨烯导电剂的优势在于能用较少的添加量,达到更加优异的电化学性能。最后对石墨烯复合材料的研究前景进行了展望。     

夹层化合物研究进展

简介了夹层化合物的基本知识，合成方法，夹层反应过程及机理，综述了夹层化合物结构鉴定，性质及应用方面的最新进展，夹层化合物可能将成为一类潜在的复合功能材料。     

无机-有机纳米复合材料：有机氮氧自由基/MnPS3夹层物的合成与磁性

合成了一个无机,有机纳米复合物(MPYNN)0.14Mn0.93PS3,即有机氮氧自由基MPYNN(N-甲基吡啶阳离子自由基)的MnPS3夹层化合物.通过X-射线粉末衍射和红外光谱等对其结构进行了表征,根据其0.56 nm的层间距扩大值推测夹层化合物中的客体分子在层间采取了分子平面近乎垂直于主体层的排列方式.通过SQUID测试了所得到的夹层化合物的磁性,结果表明夹层化合物(MPYNN)0.14Mn0.93PS3在10 K以上具有顺磁特性,而在7 K时出现了一个明显的磁相变,表现出自发磁化.     

夹层化合物

近半个世纪以来,在国外对夹层化合物的研究已引起许多科学工作者的兴趣,由于夹层作用不同于一般的化学反应,对夹层过程、结构及物性展开了广泛的研究。通过综述文章及许多论文刊载情况看,逐渐由化学领域转入物理或材料科学领域,同时在应用方面也作了探索。本文拟对夹层化合物的基本概况及应用作简单介绍。     

MoS2/Lys夹层化合物的合成、表征及电催化性能

本文运用直接反应法合成了MoS_2/Lys夹层化合物,并用X-射线粉末衍射,红外光谱和热重分析等手段对材料进行表征,制备MoS_2/Lys夹层化合物修饰碳糊电极,研究了亚硝酸盐在该修饰电极上的电化学性能。结果表明,在磷酸盐缓冲溶液中,MoS_2/Lys修饰电极对亚硝酸盐的电化学响应具有很好的催化作用。     

PEO／V2O5复合薄膜中Li^＋的位置与电子结构研究

采用自洽场离散变分Xα（SCC-DV-Xα）方法对纯V2O5及夹层V2O5的能带结构、态密度、键强度、电子集居数等进行了研究，结果表明，Li^ 引入V2O5层间的最佳位置在在双键氧之下（或之上），且靠近层的中心位置，此时它与周围原子间的作用力非常微弱，并且材料的导电性增强，使夹层复合材料Li^ 注入／脱出具有很好的可逆性和较好的光学性质。     

Solution-processed anodes from layer-structure materials for high-efficiency polymer light-emitting diodes

The development of low-cost, large-area electronic applications requires the deposition of active materials in simple and inexpensive techniques at room temperature, properties usually associated with polymer films. In this study, we demonstrate the integration of solution-processed inorganic films in light-emitting diodes. The layered transition metal dichalcogenide (LTMDC) films are deposited through Li intercalation and exfoliation in aqueous solution and partially oxidized in an oxygen plasma generator. The chemical composition and thickness of the LTMDC and corresponding transition metal oxide (TMO) films are investigated by X-ray photoelectron spectroscopy. The morphology and topography of the films are studied by atomic force microscopy. X-ray powder diffraction is used to determine the orientation of the LTMDC film. Finally, the LTMDC and their corresponding oxides are utilized as hole-injecting and electron-blocking materials in polymer light-emitting diodes with the general structure ITO/LTMDC/TMO/polyfluorene/Ca/Al. Efficient hole injection and electron blocking by the inorganic layers result in outstanding device performance and high efficiency.     

Effect of the Solvent on the Conformation of Isolated MEH‐PPV Chains Intercalated Into SnS2

Photophysical processes in conjugated polymers are influenced by two competing effects: the extent of excited state delocalization along a chain, and the electronic interaction between chains. Experimentally, it is often difficult to separate the two because both are controlled by chain conformation. Here we demonstrate that it is possible to modify intra‐chain delocalization without inducing inter‐chain interactions by intercalating polymer monolayers between the sheets of an inorganic layered matrix. The red‐emitting conjugated polymer, MEH‐PPV, is confined to the interlayer space of layered SnS₂. The formation of isolated polymer monolayers between the SnS₂ sheets is confirmed by X‐ray diffraction measurements. Photoluminescence excitation (PLE) and photoluminescence (PL) spectra of the incorporated MEH‐PPV chains reveal that the morphology of the incorporated chains can be varied through the choice of solvent used for chain intercalation. Incorporation from chloroform results in more extended conformations compared to intercalation from xylene. Even highly twisted conformations can be achieved when the incorporation occurs from a methanol:chloroform mixture. The PL spectra of the MEH‐PPV incorporated SnS₂ nanocomposites using the different solvents are in good agreement with the PL spectra of the same solutions, indicating that the conformation of the polymer chains in the solutions is retained upon intercalation into the inorganic host. Therefore, intercalation of conjugated polymer chains into layered hosts enables the study of intra‐chain photophysical processes as a function of chain conformation.     

Novel silicon super bases at DFT level of theory: effects of fused benzene rings on the basicity of 2,4,6-cycloheptatrienesilylene

Research on Chemical Intermediates - Super bases are extremely important compounds with high proton affinities (PAs) and many applications in organic, inorganic, polymer, and photochemistry. Here,...     

Chemiluminescence in analytical chemistry

Analytical applications based on chemiluminescence are reviewed. Analyses in the gas phase for atmospheric pollutants such as sulphur compounds, ozone and oxides of nitrogen are described. The commonest chemiluminescent systems used in the liquid phase are then discussed. Their applications as indicators in different types of titration are outlined. Determinations of organic and inorganic substances are classified according to their action as oxidant, catalyst or inhibitor. Special applications are described in fields such as forensic science, microbiology, polymer technology, radiation chemistry and flow mechanics.     

Facile preparation of graphite intercalation compounds in alkali solution

Graphite intercalation compounds are often prepared by flake graphite, oxidants, inorganic acids, organic acids and intercalated ions which are usually hydrogen protons between the graphene planes. They are also known as the acid-treated graphite intercalation compounds. In this work, alkaline graphite intercalation compounds were prepared by flake graphite, K₂Cr₂O₇, concentrated H₂SO₄ and NaOH, and the morphology and structure were characterized by Electron microscopy and X-ray techniques. The results display that the combination of neutralisation heat and oxidation capability produced by K₂Cr₂O₇ can break the bonds to produce the spaces between the graphene planes and hydroxyl ions also intercalate into the graphene planes to form alkaline graphite intercalation compounds in alkali solution. The morphology and structure of alkaline graphite intercalation compounds are analogous to the ones of the acid-treated graphite intercalation compounds, but the intercalated ions and the expansion volume are different. The results show that the method is an innovation.     

A novel organic intercalation system with layered polymer crystals as the host compounds derived from 1,3-diene carboxylic acids

A new type of organic intercalation system using poly(muconic acid) and poly(sorbic acid) crystals as the host compounds is described. The layered polymer crystals as the host are derived from benzyl-, dodecyl-, or naphthylmethylammonium salts of (Z,Z)-muconic or (E,E)-sorbic acids by topochemical polymerization. The subsequent solid-state hydrolysis of the resulting ammonium polymer crystals provides the corresponding carboxylic acid polymer crystals. When alkylamines are reacted with poly(muconic acid) or poly(sorbic acid) crystals dispersed in methanol at room temperature for a few hours, the intercalation proceeds to give layered ammonium polymer crystals via solid-state reactions, in which the polymers maintain a layered structure throughout. The interplanar spacing value of the polymer crystals changes according to the size of the guest molecules; that is, it exactly depends on the carbon number of the alkylamines used for each reaction of poly(muconic acid) or poly(sorbic acid) crystals. The stacking structure of alkyl chains with a tilt in the intercalated alkylammonium layers exists irrespective of the chemical and crystal structures of the host polymers. The intercalation of higher alkylamines into poly(muconic acid) crystals proceeds fast and quantitatively, while the conversion is dependent on the reaction conditions such as the structure and amount of the amine and the reaction time during the intercalation with poly(sorbic acid) crystals, due to the difference in the repeating layered structures of these polymer crystals. Some functional amines are also used as the guest molecules for this organic intercalation system.     

Intercalation compound of diclofenac sodium with layered inorganic compounds as a new drug material

The intercalation reaction of diclofenac sodium (DFS) with layered inorganic compounds, gamma-titanium phosphate (gamma-TiP), proton type titanium oxide (H-TiO2) and sodium type synthetic mica (Na-TSM), was examined on. The direct reaction of DFS in ethanol-water mixed solvent resulted in the large amount accommodation of DFS. The amount of intercalated DFS was the order of gamma-TiP>H-TiO2>Na-TSM corresponding to the order of acidity. The intercalation using phospholiopids was also examined to assist the intercalation reaction. However, the amount of intercalated DFS was rather small in comparison with those in the direct reaction. DFS accommodated in gamma-TiP dissolved into neutral and basic buffer solution stoichiometry while scarcely dissolved in the acidic solution. The mechanism of the intercalation and reverse dissolution was successfully accounted according to the ion-exchange mechanism between Na+ in DFS and H+ in gamma-TiP. The dissolution from tablet of DFS/gamma-TiP intercalation compound was examined by using a disintegrator. It was found that the dissolution rate appropriately controlled by mixing the disintegrator. The present results suggested the different possibilities in the clinical field to use layered inorganic compounds such as drug delivery system (DDS).     

聚合物纳米材料研究进展——Ⅱ.聚合物/无机纳米复合材料

复合物纳米材料包括纳米聚合物和聚合物／无机纳米复合材料。本文综述了聚合物／无机纳米复合材料的研究进展，重点介绍了溶胶－凝胶法，原位生成法，模板法，插层复合，沉积法，机械粉碎，分子平壤 ，溶液或融混合法的研究进展。     

Orientational control of guest molecules in an organic intercalation system by host polymer tacticity

Four kinds of stereoregular poly(muconic acid)s, which are synthesized by topochemical polymerization and subsequent solid-state hydrolysis, are used as the organic host materials for intercalation. We describe the reaction behavior and layered structure of intercalation compounds using stereoregular poly(muconic acid)s and n-alkylamines as host and guest, respectively. The packing structure of the guest alkylamines was determined by X-ray diffractions as well as IR and Raman spectroscopies. We have found that the orientation of the guest molecules is controlled by the host polymer tacticity, depending on the structure of the two-dimensional hydrogen-bonding network formed in the polymer sheets of the crystals.     

Nanocomposites of NLO chromophore‐modified layered silicates and polypropylene

Intercalation of guest species into layered inorganic solids is a method of producing ordered inorganic–organic assemblies with unique microstructures controlled by host–guest and guest–guest interactions. Smectite clay minerals, such as montmorillonite, having appropriate functional molecules in between the silicate layers are supposed to exhibit a wide range of novel characteristics. Nanocomposite material based on maleic anhydride‐grafted polypropylene and dye‐modified layered silicate was developed. Characteristics of organo‐modified montmorillonite particles and polymer/clay hybrids have been investigated through FTIR, SAXS, DSC, UV measurements, and transmission electron microscopy. The results of the intercalation process, structural characterization, and thermal properties will be discussed in comparison with the intercalation and nanocomposite preparation results. The intercalation was successfully conducted by the ion‐exchange method. It was shown that intercalated dibenzilidene acetone type chromophores exist in the clay galleries in an aggregated form, probably as J‐aggregates. This feature strongly effects on optical and nonlinear optical properties of nanocomposites. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 2493–2502, 2005