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1.
任红  张萍  吴平  芦菲 《化学进展》2012,24(5):769-775
配位聚合物由于具有丰富的拓扑结构,并在客体交换与分离、气体存储、手性拆分、选择性催化、分子识别、荧光和磁性等方面有潜在应用,已成为当前配位化学、材料化学和晶体工程学的热点研究领域之一。本文结合近年来本课题组的研究工作及国内外相关研究进展,概述了含三唑-有机羧酸混合配体的配位聚合物结构和性质,着重讨论了有机羧酸配体在构筑配合物结构中的作用,并对今后的研究和发展方向进行了展望。  相似文献   

2.
We have found a new way, a metal-organic coordination gel template method, to generate polymer monoliths with an essentially macropore size, in which the pores are organized spontaneously into continuous networks; furthermore, the resulting macroporous monoliths have potential applications in high-throughput and high-efficiency separation of proteins.  相似文献   

3.
The magnetothermal properties of a coordination polymer and a metal-organic framework (MOF) based on Gd(3+) ions are reported. An equally large cryogenic magnetocaloric effect (MCE) is found, irrespective of the dimensionality. This combined with their robustness makes them appealing for widespread magnetic refrigeration applications.  相似文献   

4.
Infinite coordination polymers are recognized as excellent platform for functionalization.Dithienylethene motifs,which are one of the most attractive functional moieties,were incorporated into an infinite coordination polymer,to deliver a‘‘smart’’porous material that can response to external stimuli.The obtained dithienylethene-based infinite coordination polymers(named Cu-DTEDBA)share the advantages of both infinite coordination polymers(porosity and stability)and dithienylethene motifs(photochromism).The physical and chemical properties of Cu-DTEDBA were characterized by FTIR,TEM,SEM,XRD,TGA,UV–vis,EDX and BET.Moreover,the combination of dithienylethene and infinite coordination polymers gives rise to a synergistic effect,which induces functional behaviors of ammonia sensor applications.Both open and closed forms of Cu-DTEDBA exhibit distinct colorimetric change upon exposure to gaseous ammonia,which is not observed in dithienylethene free molecules.  相似文献   

5.
π‐d Conjugated coordination polymers (CCPs) have attracted much attention for various applications, although the chemical states and structures of many CCPs are still blurry. Now, a one‐dimensional (1D) π‐d conjugated coordination polymer for high performance sodium‐ion batteries is presented. The chemical states of the obtained coordination polymer are clearly revealed. The electrochemical process undergoes a three‐electron reaction and the structure transforms from C=N double bonds and NiII to C?N single bonds and NiI, respectively. Our unintentional experiments provided visual confirmation of NiI. The existence of NiI was further corroborated by its X‐ray absorption near‐edge structure (XANES) and its catalytic activity in Negishi cross‐coupling.  相似文献   

6.
室温离子液体中的聚合反应   总被引:7,自引:0,他引:7  
综述了近年来在室温离子液体中聚合反应的研究进展,特别是在配位聚合、自由基聚合、离子聚合及共聚反应,活性自由基聚合,电化学聚合等方面的进展情况;还介绍了离子液体在高分子材料方面的应用情况,展望了离子液体在该领域的应用前景.  相似文献   

7.
An unusual 1D‐to‐3D transformation of a coordination polymer based on organic linkers containing highly polar push–pull π‐conjugated side chains is reported. The coordination polymers are synthesized from zinc nitrate and an organic linker, namely, 2,5‐bis{4‐[1‐(4‐nitrophenyl)pyrrolidin‐2‐yl]butoxy}terephthalic acid, which possesses highly polar (4‐nitrophenyl)pyrrolidine groups, with high dipole moments of about 7 D. The coordination polymers exhibit an unusual transformation from a soluble, solvent‐stabilized 1D coordination polymer into an insoluble, metal–organic framework (MOF)‐like 3D coordination polymer. The coordination polymer exhibits good film‐forming ability, and the MOF‐like films are insoluble in conventional organic solvents.  相似文献   

8.
Many applications of molecule based magnets, whether they are in information storage, displays, or as components in electronic or spintronic devices, will require putting the active materials on a surface or interfacing them with other components. Although there are many examples of molecule-based magnets, the families of tetracyanoethylene (TCNE) based magnets and Prussian-blue analogs possess materials properties that are close to those required for practical applications, and are the most advanced with respect to studies as thin films. This critical review focuses on fabrication and characterization of thin films of TCNE and Prussian-blue analog coordination polymer magnets. Emphasis is on current developments in thin film heterostructures and potential spintronics applications (135 references).  相似文献   

9.
基于国内外最新研究文献 ,系统论述了近年来液晶金属配位聚合物的合成方法、液晶行为及应用前景。指出液晶金属配位聚合物的合成方法可归纳为直接配位法、单体配位法、交联配位法和聚合物反应法四种。液晶金属配位聚合物一般呈现热致液晶行为 ,显示稳定的向列液晶相或近晶液晶相。有些金属配位聚合物还呈现互变性近晶态或单变液晶性。液晶金属配位聚合物具有金属的特殊性质 ,是一种新型高性能磁导、电导和光导材料 ,可望应用于液晶显示材料、磁性信息储存薄膜材料、润滑剂和各向异性催化剂等。  相似文献   

10.
唐洁渊  林美娟  章文贡 《化学学报》2001,59(12):2202-2208
研究了铕(Ⅲ)和二苯甲酰甲烷(HDBM)形成的有机配合物与聚(苯乙烯-丙烯酸)(PSAA)发生配位反应得到配位聚合物Eu(Ⅲ)-DBM-PSAA。红外光谱、紫外光谱、X光电子能谱的测试表明了Eu^3^+分别与PSAA,DBM^-发生配位,元素分析和电导率测定结果证明了一个Eu^3^+分别与PSAA中三个链节的羧基和一个DBM^-发生配位。从而得到该配合物的结构并对其荧光性进行研究,配位聚合物不能溶于普通有机溶剂,只能溶于丙三醇/异丙醇混合溶剂常温下配合物在紫外光下发出强的红光,主要是Eu离子的^5D0→^7F2的跃迁。  相似文献   

11.
This review concentrates on the use of metals in the formulation of epoxy resin systems and the effect that this has on the physical and mechanical properties of the polymer system. Epoxy resins are one of the most important higher performance polymer systems in use today, ranging from simple two-part adhesives and sports equipment to high-tech applications such as formula one racing cars and the aerospace industry. Epoxy resins are capable of undergoing homopolymerisation, although this process generally yields products with inadequate properties for high-tech applications. Consequently, in many cases catalysts, additives and co-curing-agents are formulated with the epoxy resin to significantly increase the storage stability, decrease the cure time and improve the final properties. The use of metals to formulate resin systems with excellent storage stability is discussed, along with the use of coordination compounds to improve cured resin properties such as fracture toughness, thermal stability and water absorption, etc.  相似文献   

12.
A new coordination-polymer-precursor route has been developed to synthesize nanowires under hydrothermal conditions. In the present work, well-aligned gamma-MnO(2) nanowires, growing along the [0 0 2] axis, have successfully been prepared by selecting an appropriate coordination polymer [[Mn(SO(4))(4,4'-bpy)(H(2)O)(2)](n)] as precursor. In comparison with the experimental results from other coordination-polymer precursors, it is found that only [[Mn(SO(4))(4,4'-bpy)(H(2)O)(2)](n)] is appropriate for the formation of gamma-MnO(2) crystal lattices during the process of oxidization. The IR absorption spectra of as-obtained precipitates at different reaction intervals minutely describe the reaction process, due to the different coordination abilities of ligands in the coordination polymer. More evidence about the mechanism will be further explored in the future study. Further observations show the ordered alignment of nanowires' tops and such well-aligned nanowires provide more possible applications in lithium batteries.  相似文献   

13.
The compound [Mn(mu-ox)(4atr)2]n (1) (ox = oxalato and 4atr = 4-amine-1,2,4-triazole) has been synthesized and characterized by FT-IR spectroscopy, thermal analysis, variable-temperature magnetic measurements, and X-ray single-crystal diffraction methods. The crystal structure of compound 1 consists of one-dimensional linear chains in which trans-[Mn(4atr)2]2+ units are sequentially bridged by centrosymmetric bis-bidentate oxalato ligands. Cryomagnetic measurements show an overall antiferromagnetic behavior of the compound. Isolated chains of this polymer have been obtained by sonication of 1 in ethanol or treatment of the polymer with NaOH and morphologically characterized on highly oriented pyrolitic graphite and mica surfaces by atomic force microscopy and scanning tunneling microscopy. The procedures employed to obtain single chains of this coordination polymer open a route for future nanotechnological applications of these types of materials.  相似文献   

14.
Lanthanide-based coordination polymer Dy(1,3,5-BTC)(H2O)6 nanobelts were successfully synthesized on a large scale through an extremely simple approach at room temperature; the size of the nanobelts can be easily tuned from several to several hundred micrometers in length, 70–600 nm in width, and 10–100 nm in thickness by varying concentrations, solvent, and surfactant reasonably. In addition, the as-obtained dysprosium benzenetricarboxylate nanobelts exhibit the characteristic emission of the Dy3+ ions, making the belt-like coordination polymer have potential applications in building minioptoelectronic devices.  相似文献   

15.
An easily recoverable and reusable enantioselective catalytic system based on the self-assembly of a coordination polymer through the use of a chiral ditopic ligand, is described for the allylic oxidation of cycloalkenes with tert-butyl perbenzoate. Upon addition of the substrates and a coordinating solvent (acetone or acetonitrile) the coordination polymer disassembles, allowing the catalysis to take place in homogeneous phase. After completion of the reaction, the catalyst reassembles as a coordination polymer upon solvent evaporation and addition of hexane, and is recovered as an insoluble solid. This way, good enantioselectivities and yields are obtained in seven consecutive operation cycles.  相似文献   

16.
Polyamic acids containing biquinolyl (biQ) fragments in the polymer backbone are capable of coordinating with NiII ions to form two types of coordination units: with one or two biQ ligands in the Ni coordination environment. The relative number of [Ni(biQ)2]2+ coordination units in the polymer chain increases with an increase in the concentration of the biQ fragments in solution and with a decrease in the conformational rigidity of the polymer. The synthesis of the nickel complexes with the polymer ligands can be carried out using both Ni salts and the electrochemical dissolution of the Ni anode.  相似文献   

17.
Coordination polymers are promising cathode materials for rechargeable alkaline batteries. Therefore, the precise modulation of these cathodes by chemical structure and in-depth structure transform study is necessary. Here, two model coordination polymer battery cathodes were designed to demonstrate the dynamic structure–performance relationship. We studied the electrochemical performance of two kinds of nickel-based coordination polymer, comprising a planar 2D cyanide-bridged network and a 3D cyanide-bridged network pillared by pyrazine molecules. The 2D coordination polymer showed serious voltage degradation with poor rate capability, whereas the 3D coordination polymer exhibited stable voltage output coupled with high rate at various current densities. The investigation revealed the underlining relationship of plateau voltage degradation and hydrolysis process of electrodes. It was revealed that the pyrazine pillar molecules in the 3D coordination polymer could suppress the hydrolysis and lead to the in situ formation of partially hydrolyzed structure with excellent electrochemical kinetics; this exhibited obvious smaller peak separation (27 mV compared with 149 mV) and hence an almost twofold increase in capacity retention (31.9 to 50.0 %) and energy density retention (18.2 to 35.9 %) at 10 A g−1.  相似文献   

18.
Protein cage nanoparticles (PCNs) are attractive platforms for developing functional nanomaterials using biomimetic approaches for functionalization and cargo encapsulation. Many strategies have been employed to direct the loading of molecular cargos inside a wide range of PCN architectures. Here we demonstrate the exploitation of a metal-ligand coordination bond with respect to the direct packing of guest molecules on the interior interface of a virus-like PCN derived from Salmonella typhimurium bacteriophage P22. The incorporation of these guest species was assessed using mass spectrometry, multiangle laser light scattering, and analytical ultracentrifugation. In addition to small-molecule encapsulation, this approach was also effective for the directed synthesis of a large macromolecular coordination polymer packed inside of the P22 capsid and initiated on the interior surface. A wide range of metals and ligands with different thermodynamic affinities and kinetic stabilities are potentially available for this approach, highlighting the potential for metal-ligand coordination chemistry to direct the site-specific incorporation of cargo molecules for a variety of applications.  相似文献   

19.
Hollow polymer-based particles are useful for the encapsulation, protection, and release of active compounds. Adding a metal-organic coordination framework shell to nanocontainers is an attractive goal because it should help control their stability and permeability while yielding new properties and functions. We have discovered that polymer capsules with a Prussian blue analogue inner shell can be synthesized by emulsion-induced assembly of a metal-containing amphiphilic block ionomer. The capsules are selectively permeable and were used as nanocontainers to encapsulate and release a model compound. Further, these nanomaterials are tunable in size and organize into 2-D close-packed arrays in the solid state. Potential applications for these materials include the encapsulation and nanopatterning of pharmaceutical, biological, and catalytic compounds.  相似文献   

20.
A supramolecular gel results from the immobilization of solvent molecules on a 3D network of gelator molecules stabilized by various supramolecular interactions that include hydrogen bonding, π–π stacking, van der Waals interactions, and halogen bonding. In a metallogel, a metal is a part of the gel network as a coordinated metal ion (in a discrete coordination complex), as a cross‐linking metal node with a multitopic ligand (in coordination polymer), and as metal nanoparticles adhered to the gel network. Although the field is relatively new, research into metallogels has experienced a considerable upsurge owing to its fundamental importance in supramolecular chemistry and various potential applications. This focus review aims to provide an insight into the development of designing metallogelators. Because of the limited scope, discussions are confined to examples pertaining to metallogelators derived from discrete coordination complexes, organometallic gelators, and coordination polymers. This review is expected to enlighten readers on the current development of designing metallogelators of the abovementioned class of molecules.  相似文献   

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