共查询到19条相似文献，搜索用时 265 毫秒
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传统的无机-有机杂化材料可以包括很多方面，如有机-无机层状复合材料、有机高分子掺杂无机粉末复合材料和功能有机分子修饰的无机材料等。随着配位聚合物晶体工程自上世纪90年代的兴起，以无机基团（如金属离子、簇合物其他纳米簇）和有机桥连配体为分子建筑块构筑的无机-有机聚集体的基础与应用基础研究，已经成为新型无机-有机杂化材料研究的重要对象和发展方向之一。由于有机组分（配体）的引入，无机-有机杂化材料具有与传统纯无机材料不同的特性。金属离子的存在，可以为这类材料提供各种潜在的物理化学性能，例如氧化还原性、磁性、光学性能、吸附性能、反应性能等。同时，与传统无机材料不同，这些杂化材料比较容易通过引入不同有机配体或者对配体的修饰，达到设计、剪裁杂化材料的结构与物理化学性质的目的，甚至可以调控杂化材料的对称性和手性。 相似文献
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《科技通报》2017,(7)
提出利用过渡金属钴合成有机框架类材料,并研究其降解染料的性能。首先,在金属有机框架合成方案中,选用2,2'-联呲啶-3,3'-二羧酸(H2bpdc)当成桥联配体,使稀土离子和过渡金属钴离子在水作溶剂的条件下,利用高温高压配位聚合反应实现有机框架材料的合成;然后,采用红外光谱分析法对产物进行聚合物配位的初步判断和官能团描述,利用X-射线单晶衍射分析仪器判读有机框架样品材料分子结构及具体晶胞参数;最后,利用XRD粉末衍射仪确定产物纯度后,即同时描述了Co-bydc材料光催化性质和降解染料性能。通过上述实验过程完成了Co(Ⅱ)有机框架的合成及其降解染料性能的分析过程。 相似文献
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<正>由多段异质材料纳米线与纳米管联结组成的纳米结构,是纳米光电子器件的重要组成单元;同时,这种结构在条形编码、光学读出、生物、催化、自组装和磁操纵等方面均有广泛的应用前景。最近,中科院固体物理研究所孟国文小组在"多段异质纳米线与纳米管组成的分支结构"研究方面 相似文献
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利用简单的手性有机配体L-酒石酸成功地合成出了一系列类似DNA螺旋构型的左、右旋的一维链状聚合物：{A[Mo2VIO4LnIII(H2O)6(C4H2O6)2]·4H2O}n (Ln = Sm, Eu, Gd, Ho, Yb, Y; C4H2O6 = L- 或 D-酒石酸； A = NH4 或 H3O)。通过水热法，巧妙地把传统的钼氧单核{MoO4}、双核{Mo2O7}以及{Mo8O26}等结构单元，通过有机配体配位的过渡金属单元交错地连接成零、一、二、三维的一系列结构新颖的化合物，这类化合物大多数具有可以容纳客体小分子的隧道或空穴，如 [Cu(4,4’-bpy)]2MoO4·2H2O，[Cu(4,4’-bpy)]2Mo2O7，[Cu(4,4’-bpy)(Hnic)(H2O)]2Mo8O26等。首次利用水热法合成出了含稀土的杂多酸类化合物，[Gd(H2O)3]3[GdMo12O42]·3H2O。该化合物是由Silverton-型的 [GdMo12O42]9- 阴离子和配位的Gd3+ 阳离子组成的。在[GdMo12O42]9- 离子中首次把顺磁性的钆(III)离子引入到该构型的中心，并且通过九配位的钆(III)离子把它们连接成具有介孔结构的三维网状化合物。该化合物的获得为今后合成类似化合物提供了一个很好的范例。在水热法合成出的化合物，[Cu2(C8H6N2)2(C7H6N2)]2[Mo8O26] 中，首次捕捉到喹喔啉的氧化产物苯并咪唑，证明了在水热条件下含氮的芳香杂环类的有机配体可以被二价铜氧化，其氧化产物进而作为配体直接与铜原子配位，最终形成新颖的上述化合物。 相似文献
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《科技通报》2016,(2)
席夫碱主要是指含有亚胺或甲亚胺特性基团(-RC=N-)化合物,席夫碱配体与金属反应形成金属配合物,研究席夫碱配体与金属反应的紫外光谱特征,分析席夫碱配体金属配合物在温和条件下的低氧化性能,优化液晶材料制备。通过实验分析方法分析席夫碱配体金属配合物性能,对金属/金属氧化物纳米粒子进行金属离子固相萃取,采用ATR作为紫外光谱四氢吡喃酮衍生端,将Au沉积物(1.286 g)溶解在50 m L的HAuCl_4(1.04 mmol·L-1)中进行晶体的制备,研究席夫碱配体与金属反应的紫外光谱特征。实验结果表明,通过该制备和实验方法能准确测量席夫碱配体金属配合物与金属反应紫外光谱特征,提高了席夫碱配体金属配合物在温和条件下的低氧化性能,为优化液晶材料制备奠定基础。 相似文献
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合成了一种以邻羧基苯甲酰二茂铁为疏水链聚乙二醇单甲醚为亲水链的新型rod-coil两亲性金属有机低聚物,并对其在溶液中的自组装行为进行了研究.研究表明,在不同的起始浓度下,该化合物可自组装形成球形、扭曲的蠕虫状胶束和囊泡,二茂铁和苯环间的π-π相互堆叠是形成扭曲型蠕虫状胶束的主要因素. 相似文献
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赵静 《科技成果管理与研究》2021,16(4):8-9
过渡金属配合物是一类重要的光功能分子材料,具有丰富的电化学、光吸收、三线态发光性能,在信息、光电器件、绿色能源等领域有重要用途.在这些应用中,分子材料通常以纳米薄膜或组装结构的形式被使用.然而金属配合物极性大、溶解性较差、分子间缺少有效相互作用,严重制约了其纳米薄膜和组装结构的制备. 相似文献
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Xue-Hua Ding Yong-Zheng Chang Chang-Jin Ou Jin-Yi Lin Ling-Hai Xie Wei Huang 《国家科学评论(英文版)》2020,7(12):1906
Halogen bonding is emerging as a significant driving force for supramolecular self-assembly and has aroused great interest during the last two decades. Among the various halogen-bonding donors, we take notice of the ability of 1,4-diiodotetrafluorobenzene (1,4-DITFB) to co-crystallize with diverse halogen-bonding acceptors in the range from neutral Lewis bases (nitrogen-containing compounds, N-oxides, chalcogenides, aromatic hydrocarbons and organometallic complexes) to anions (halide ions, thio/selenocyanate ions and tetrahedral oxyanions), leading to a great variety of supramolecular architectures such as discrete assemblies, 1D infinite chains and 2D/3D networks. Some of them act as promising functional materials (e.g. fluorescence, phosphorescence, optical waveguide, laser, non-linear optics, dielectric and magnetism) and soft materials (e.g. liquid crystal and supramolecular gel). Here we focus on the supramolecular structures of multicomponent complexes and their related physicochemical properties, highlight representative examples and show clearly the main directions that remain to be developed and improved in this area. From the point of view of crystal engineering and supramolecular chemistry, the complexes summarized here should give helpful information for further design and investigation of the elusive category of halogen-bonding supramolecular functional materials. 相似文献
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Complexation of π-conjugated ligands by metal or semimetal ions leads to the enhancement of the planarity and rigidity of π-conjugated systems. Boron, especially, has played a central role in the design of luminescent main-group complexes. However, these complexes still suffer the disadvantage of aggregation-caused quenching as well as typical organic fluorophores. It has recently been reported that some types of boron complexes exhibit the aggregation-induced emission (AIE) property. Moreover, AIE behavior from complexes and organometallic compounds composed of the other group 13 elements, such as aluminum and gallium, has emerged in this decade. These observations greatly encourage us to develop advanced functional materials based on the group 13 elements. Indeed, recent research has demonstrated that these classes of materials are potentially versatile scaffolds for constructing chromic luminophores, efficiently emissive π-conjugated polymers and so on. This review mainly describes AIE-active group 13 complexes with four-coordinate structures and their application as photo-functional materials. Proposed mechanisms of the origins of AIE behavior are briefly discussed. 相似文献
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Despite extensive research and several stunning breakthroughs in the synthesis of interlocked molecular species, [3]catenanes, Borromean rings and ring-in-ring complexes are exceedingly rare and their targeted synthesis remains a formidable challenge. Herein, a series of Cp*Rh-based homogeneous and heterogeneous interlocked structures have been prepared by coordination-driven self-assembly, not only including metalla[2]catenanes and molecular Borromean rings, but also linear metalla[3]catenanes and ring-in-ring complexes. The interlocked structures are all based on bithiophenyl groups. The bithiophenyl groups effectively enhance the strength of the inter-ring interactions and play a crucial role in the formation of these interlocked structures. By taking advantage of the strong interaction between π-donor (D) and π-acceptor (A) groups, the electron-deficient methylviologen cation was introduced into a cationic metallarectangle based on bithiophenyl groups. Taking inspiration from these results, a cationic metallarectangle based on A units was threaded into a metallarectangle based on D units, leading to a heterogeneous D–A ring-in-ring structure. 相似文献
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Sheng-Nan Sun Ning Li Jiang Liu Wen-Xin Ji Long-Zhang Dong Yi-Rong Wang Ya-Qian Lan 《国家科学评论(英文版)》2021,8(3)
Identification of the real catalytic site in CO2 reduction reaction (CO2RR) is critical for the rational design of catalysts and the understanding of reactive mechanisms. In this study, the catalytic activity of pyridine-containing materials was for the first time structurally demonstrated in CO2RR by crystalline supramolecular coordination compounds model system. The system consists of three stable supramolecular coordination compounds (Ni-TPYP, Ni-TPYP-1 and Ni-TPP) with different numbers (4, 2 and 0) of active pyridine groups (i.e. uncoordinated pyridine nitrogen atoms). The electrocatalytic test results show that with the decrease of the number of active pyridine groups, the CO2RR performance is gradually reduced, mainly showing the reduction of highest FECO (99.8%, 83.7% and 25.6%, respectively). The crystallographic, experimental and theoretical evidences prove that the CO2RR activity is more likely derived from uncoordinated pyridine nitrogen than the electrocatalytic inert metal nickel in porphyrin center. This work serves as an important case study for the identification of electrocatalytic activity of pyridine-containing materials in CO2RR by simple supramolecular model system. 相似文献
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Coordination-driven self-assembly of metallacages has garnered significant interest because of their 3D layout and cavity-cored nature. The well-defined, highly tunable metallacage structures render them particularly attractive for investigating the properties of luminophores, as well as for inducing novel photophysical characters that enable widespread applications. In this review, we summarize the recent advances in synthetic methodologies for light-emitting metallacages, and highlight some representative applications of these metallacages. In particular, we focus on the favorable photophysical properties—including high luminescence efficiency in various physical states, good modularity in photophysical properties and stimulus responsiveness—that have resulted from incorporating ligands displaying aggregation-induced emission (AIE) into metallacages. These features show that the synergy between carrying out coordination-driven self-assembly and using luminophores with novel photophysical characteristics like AIE could stimulate the development of supramolecular luminophores for applications in fields as diverse as sensing, biomedicine and catalysis. 相似文献
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智能材料与界面材料有机结合，赋予界面材料智能特性将是研究智能材料的一个新领域. 通过水溶液以及低温水热合成方法，我们分别制备了氧化锌以及氧化钛一维无机半导体纳米棒薄膜。结合它们特殊的微观/宏观表面几何结构以及表面紫外光敏感性，在紫外光以及暗处保存的交替作用下，我们实现了表面超疏水以及超亲水的可逆转变性能。在这里，我们还讨论了一维纳米材料表面浸润性可逆转变的机理。这一原理可以拓展到其它具有类似纳米结构和外场相应性的纳米表面中。这些具有智能相应性的材料具有极其重要和广泛的工业用前景。 相似文献
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Three dimensional (3D) stepped electrodes dramatically improve the flow rate and frequency range of ac electro-osmotic pumps, compared to planar electrodes. However, the fabrication of 3D stepped electrodes for ac electro-osmosis (ACEO) pumps usually involves several processing steps. This paper demonstrates results from ACEO pumps produced by a faster and less expensive method to fabricate the 3D electrodes—extending the previous work to disposable devices. The method is based on shadowed evaporation of metal on an insulating substrate that can be injection molded. Flow velocities through the 3D ACEO pump are similar to those seen in the previous work. 相似文献
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采用廉价的催化剂代替昂贵的金属,低成本的一氧化碳代替氢气乃至光气,一直是人们追求的目标.综述了非金属硒在含碳、氮、氧、硫类有机化合物中的催化羰基化反应,以及在Se/CO/H2 O体系中一些有机化合物的高选择性还原反应,介绍了近期的一些新进展.催化剂量的硒在温和条件下,即可活化一氧化碳而直接进行羰基化和还原反应,特别是发展了将硝基化合物的还原羰基化与胺的氧化羰基化相结合,合成一系列精细化学品和生物化学品.催化剂硒在催化反应中表现出反应过程相转移的特性,兼具了多相催化与均相催化的优点,是反应过程相转移概念中的典型实例.硒催化反应的特点是反应物转化率高,反应选择性专一,原子经济性高,对环境友好,且可部分替代光气合成法 相似文献
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Bo Han Chen Yang Xiaolong Xu Yuehui Li Ruochen Shi Kaihui Liu Haicheng Wang Yu Ye Jing Lu Dapeng Yu Peng Gao 《国家科学评论(英文版)》2021,8(2)
Contact interface properties are important in determining the performances of devices that are based on atomically thin two-dimensional (2D) materials, especially for those with short channels. Understanding the contact interface is therefore important to design better devices. Herein, we use scanning transmission electron microscopy, electron energy loss spectroscopy, and first-principles calculations to reveal the electronic structures within the metallic (1T′)-semiconducting (2H) MoTe2 coplanar phase boundary across a wide spectral range and correlate its properties to atomic structures. We find that the 2H-MoTe2 excitonic peaks cross the phase boundary into the 1T′ phase within a range of approximately 150 nm. The 1T′-MoTe2 crystal field can penetrate the boundary and extend into the 2H phase by approximately two unit-cells. The plasmonic oscillations exhibit strong angle dependence, that is a red-shift of π+σ (approximately 0.3–1.2 eV) occurs within 4 nm at 1T′/2H-MoTe2 boundaries with large tilt angles, but there is no shift at zero-tilted boundaries. These atomic-scale measurements reveal the structure–property relationships of the 1T′/2H-MoTe2 boundary, providing useful information for phase boundary engineering and device development based on 2D materials. 相似文献