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1.
选取易于制备的MOFs(ZJU-28)为功能性载体,将具有非线性光学性质的2种阳离子染料DBTM与载体孔道中的二甲胺阳离子进行交换,实现阳离子型有机荧光离子在金属有机框架中定向组装,获得具有非线性光学效应的复合材料。强极性染料离子DBTM在晶体孔道中的定向排布,改变了原有MOFs晶体的中心对称性。通过共聚焦显微镜观察到,原来不具有非线性光学效应的ZJU-28晶体通过有机阳离子交换后,形成的DB@ZJU-28和TM@ZJU-28复合材料具有较强的倍频效应和双光子荧光。  相似文献   

2.
金属有机骨架(MOFs)是由有机配体与金属离子或金属离子簇通过配位作用自组装而成的一种具有永久孔道性的开放结晶骨架,通常也被称为多孔配位聚合物(PCPS)。因为其较大的比表面积、规整的孔道结构、良好的热稳定性和化学可裁剪性,使其在多个领域具有广阔的应用前景。近年来,随着MOFs在传感领域的发展,许多不同的功能基团被引入到MOFs的孔道中,研制出具有荧光识别性能的MOFs。本论文综述了近几年来基于MOFs的化学传感器在离子识别、pH检测、挥发性有机物和气体检测、爆炸物识别和生物分子检测等关键领域的研究进展,并对MOFs在化学传感器的应用前景进行了展望。  相似文献   

3.
摘 要 金属有机骨架(Metal Organic Framework,MOFs)是由有机配体与金属离子或金属离子簇通过配位作用自组装而成的一种具有永久孔道性的开放结晶骨架,通常也被称为配位聚合物(PCPS)。因为其较大的比表面积、规整的孔道结构、热稳定性和化学可裁剪性,使其在多个领域具有广阔的应用前景。近年来,随着MOFs在传感领域的发展,许多不同的功能基团被引入到MOFs的孔道中,研制出具有荧光识别性能的MOFs。本论文综述了近几年来基于MOFs的化学传感器在离子识别、PH检测、挥发性有机物和气体检测、爆炸物识别和生物分子检测等关键领域的研究进展,并对MOFs在化学传感器的应用前景进行了展望。  相似文献   

4.
谭远铭  孟皓  张霞 《化学进展》2019,31(7):980-995
全球工业的发展带来了严重的水污染问题,对含各类有机和无机污染物工业废水的处理也成为了重要研究课题。金属-有机骨架(Metal-Organic Frameworks, MOFs)化合物由于其大比表面积、高孔隙率、有序孔道结构及可调节孔道物理化学性质、热稳定性高、易于合成和丰富的开放活性位点等特点,在诸多领域得到广泛应用,其中在固相吸附/分离领域,特别是吸附水中污染物方面展现出良好应用前景。通过合成后改性、使用含取代基配体原位合成、与特定功能材料复合等方法实现MOFs功能化,可有效增加MOFs材料的吸附活性位点,提高吸附性能和吸附选择性。与MOFs颗粒相比较,MOFs/聚合物复合膜结合了MOFs颗粒的结构与物理化学特性以及聚合物薄膜优秀的分离/载体性能,在有机染料及重金属离子的吸附中表现出优秀的吸附/分离性能。本文重点综述了以染料和重金属离子为代表的有机、无机污染物的吸附去除为目标的MOFs功能化方法,以及MOFs/聚合物复合膜的制备方法,并对未来研究方向和研究前景进行展望。  相似文献   

5.
新型金属有机骨架(MOFs)材料是一类比较新颖的可用作光催化剂的潜在材料.它是由金属离子或金属簇单元与有机配体通过配位作用自组装形成的一类具有周期性多维网络结构的多孔晶态材料.MOFs结构具有高度的有序性、一定程度上的可设计性和可剪裁性,其高度发达的孔结构使得它具有超高的比表面积.MOFs结构中的金属簇被认为可以扮演半导体量子点的角色,同时其有机配体基于"天线效应",在光激发条件下用来活化这些金属簇,从而使得MOFs成为可能的光催化剂.ZIF-9由角共享四面体CoN4单元组成,其中Co2+阳离子和苯并咪唑阴离子之间的配位键是N供体配体,因而具有良好的热稳定性和较高的碳氮含量.本文在一定浓度的甲醇溶液中通过光沉积法将CuO附着于ZIF-9表面上,用于光催化活性测试,并与g-C_3N_4/CuO催化剂进行了比较.结果表明,ZIF-9/CuO催化剂活性是g-C_3N_4/CuO催化剂的19.4倍.这是由于比表面积的不同,导致所吸附的染料与暴露的活性位点的不同.通过SEM,TEM,EDS,XRD,XPS,UV-Vis和稳态瞬态荧光等手段系统研究了催化剂反应动力学行为及内在机理.稳态荧光结果表明,染料的荧光发射峰和ZIF-9的吸收峰之间没有明显的重叠,染料的激发电子可以在该反应系统中从染料分子转移到ZIF-9上.除了一部分电子直接传输到达ZIF-9表面,更多的电子将最终通过CuO到达催化剂表面,最后与反应溶液中的H~+结合生成H_2,EY-ZIF-9/CuO(40%)的荧光衰减可以用双指数荧光衰减动力学即动态淬火机理.表明CuO的引入可以增强染料EY分子的聚集,从而增加该催化剂活性.  相似文献   

6.
聚合物非线性光学材料   总被引:3,自引:0,他引:3  
最近,有机非线性光学材料已引起了人们极大的兴趣。一些可极化有机分子具有很大的分子超极化率,可惜,受晶体对称性的限制仅有少数晶体具有二阶非线性光学效应。极化聚合物可以产生统计非中心对称的环境,使材料的二阶特性显示出来。本文在简单介绍了有机非线性光学和极化的原理后,综述了聚合物二阶非线性光学材料的研究进展。此外,对聚合物的三阶非线性光学效应的研究也作了介绍。  相似文献   

7.
金属有机骨架复合材料RhB/MOF-5的制备及其发光性质   总被引:2,自引:0,他引:2  
通过溶剂扩散法成功地将激光染料分子罗丹明B(RhB)组装到了金属有机骨架材料MOF-5中, 从而制备出具有光学活性的主-客体金属有机骨架复合材料RhB/MOF-5. 通过光学显微镜、XRD、FTIR、UV-Vis和PL表征证明RhB存在于MOF-5晶体孔道中, 而且该金属有机骨架复合材料表现出很好的光致发光性质.  相似文献   

8.
金属-有机框架(MOFs)化合物由于其特定的孔道/孔洞结构以及在气体吸附/存储与分离、化学传感、光学、磁学以及荧光检测等方面的良好性能及潜在应用而成为当前人们关心和研究的热点。本文聚焦MOFs在溶剂分子和有机小分子荧光识别及传感方面的研究工作,着重介绍该领域近期的研究进展,并对该领域今后的发展进行了展望。  相似文献   

9.
汤雯淇  孟莎莎  徐铭  古志远 《色谱》2021,39(1):57-68
金属有机骨架材料(MOFs)是一类由有机配体和金属离子(或金属簇)自组装形成的新型多功能材料。MOFs具有孔隙度高、比表面积大、孔径可调、化学和热稳定性高等特点,被广泛应用于吸附、分离、催化等多个领域。近年来,MOFs作为新型气相色谱固定相用于分离异构体受到了广泛关注。与传统无机多孔材料相比,MOFs在结构和功能上展现出高度的可调性,通过合理地选择配体和金属中心,可以设计合成具有不同孔道大小和孔道环境的MOFs,从而分别从热力学和动力学角度优化色谱分离效果,有效提高分离选择性。该文结合MOFs的结构,讨论了MOFs气相色谱固定相分离不同类型分析物的分离机理。分离机理主要包括MOFs孔道的分子筛效应或形状选择性,MOFs不饱和的金属位点与分析物中不同的官能团之间产生的相互作用,分析物与MOFs孔道之间产生的不同范德华力、π-π相互作用和氢键相互作用。此外,MOFs的手性分离可能主要依赖于外消旋体与手性MOFs中手性活性位点之间的相互作用。该文也对不同分析目标物进行了归类,综述了多种MOFs气相色谱固定相对烷烃、二甲苯异构体和乙基甲苯、外消旋体、含氧有机物、环境有机污染物的气相色谱分离效果。最后,该文还对MOFs在该领域的应用进行了总结与展望,旨在为MOFs气相色谱高效分离的研究提供参考。  相似文献   

10.
属-有机框架(MOFs)化合物由于其特定的孔道/孔洞结构以及在气体吸附/存储与分离、化学传感、光学、磁学以及荧光检测等方面的良好性能及潜在应用而成为当前人们关心和研究的热点。本文聚焦MOFs在溶剂分子和有机小分子荧光识别及传感方面的研究工作,着重介绍该领域近期的研究进展,并对该领域今后的发展进行了展望。  相似文献   

11.
The synthesis and characterization of binary Cu(II)- (1), Co(II)- (2), Ni(II)- (3), Mn(II)- (4), Cr(III)- (5), Fe(III)- (6), La(III)- (7), UO2(VI)- (8) complexes with sparfloxacin (HL1) and ternary Cu(II)- (9), Co(II)- (10), Ni(II)- (11), Mn(II)- (12), Cr(III)- (13), Fe(III)- (14), La(III)- (15), UO2(VI)- (16) complexes with sparfloxacin (HL1) and dl-alanine (H2L2) complexes are reported using elemental analysis, molar conductance, magnetic susceptibility, IR, UV–Vis, thermal analysis and 1H-NMR spectral studies.The molar conductance measurements of all the complexes in DMF solution correspond to non-electrolytic nature.All complexes were of the high-spin type and found to have six-coordinate octahedral geometry except the Cu(II) complexes which were four coordinate, square planar and U- and La-atoms in the uranyl and lanthanide have a pentagonal bipyramidal coordination sphere. The antimicrobial activity of these complexes has been screened against two Gram-positive and two Gram-negative bacteria. Antifungal activity against two different fungi has been evaluated and compared with reference drug sparfloxacin. All the binary and ternary complexes showed remarkable potential antimicrobial activity higher than the recommended standard agents. Ni(II)- and Mn(II) complexes exhibited higher potency as compared to the parent drug against Gram-negative bacteria.  相似文献   

12.
Abstract

When 3,4,5,6-tetrachloro-1,2-benzoquinone (1) was reacted with two molar amounts of triethylphosphonoacetate (I), the corresponding 5,6,7,8-tetrachlorocoumarin-4-carbethoxy-3-diethylphosphonate (4) was obtained. Moreover, phenanthrene-9,10-quinone (2) was converted by reaction of Wittig-Horner reagent (I) into 2,3-dicarbethoxy-phenanthro[9,10-b]dihydrofuran (5) and the dimeric form (6). On the other hand, adducts (7) and (8) were isolated from the reaction of acenaphthenequinone (3) with triethylphosphonoacetate (I). Possible reaction mechanisms are considered and the structure of the new compounds (4), (5, 6) and (7, 8) was confirmed on the basis of the elemental analysis and spectral studies.  相似文献   

13.
从L-α-脯氨酸出发,经过酯化、N-烷基化、与格氏试剂反应合成了6个未见文献报道的(S)-(+)-N-取代吡咯烷甲醇衍生物3a~3f,其结构经IR,1HNMR和元素分析测定确证.并用X射线单晶衍射法测定了化合物(S)-(+)-1-[N-(5-氯-2-噻唑甲基)-2-吡咯烷基]-1,1-二苯基甲醇(3e)的晶体结构.晶体为单斜晶系,空间群为P2(1),a=0.8737(14)nm,b=0.9098(14)nm,c=1.2180(17)nm,α=90.00°,β=92.55(3)°,γ=90.00°,V=0.9671(3)nm3,Z=2,Dc=1.3217g/cm3,F(000)=404,R=0.0584,wR=0.1335.  相似文献   

14.
A homologous series of new chiral liquid crystal compounds, M6BnB (n = 2, 4, 6, 8, 10, 12, 14, 16, 18), with varying length of n-alkoxy chains at one end, was formed by covalently linking a chiral (?)-menthyl with biphenyl-benzoate via adipoyloxy spacer group. A combination of analysis methods such as Fourier transform infrared, 1H NMR spectra, differential scanning calorimetry, polarised optical microscopy and X-ray diffraction was carried out to systematically investigate their phase structures and phase transition behaviours. The length of the flexible terminal alkoxy group has a profound influence on the clearing points (Tiso) and Tiso decrease with the increase of alkoxy chain (n). In addition, increasing the length of the terminal alkoxy group tends to narrow the temperature range of the N* phase and favour the development of chiral smectic C phase.  相似文献   

15.
Colorimetric detection of anions (HSO4? and CN?) was achieved via analyte triggered colour changing of the dipodal and tripodal sensors in CH3CN–H2O (1:1). The sensors exhibited very sharp visual colour changes and fluorescence quenching–enhancing effect upon addition of the HSO4? and CN?. The large downfield shift of the NH proton signals in 1H-NMR complexation studies and quantum chemical DFT calculations proved the formation of hydrogen-bonded complexes where no proton transfer mechanism was found.  相似文献   

16.
Abstract

The crystal and molecular structure of N-(O,O-diisopropyl phosphoryl)-trans-4-hydroxy-D,L-proline has been determined by X-ray diffraction analysis and is compared with proline or hydroxyproline residue in a peptide chain described in the literature. The compound crystallized in orthorhombic system with space group P212121, a=6.934(2), b=8.694(3), c=26.727(7) Å, V=1611.3(8) Å3, Z=4, Dx=1.22 g/cm3. The structure was solved by direct method and refined by anisotropic least squares to a discrepancy index R=0.072. In the compound, the nitrogen atom is trigonal and its remaining 2p orbital is conjugated with the P?Oπ system; the conformation of the phosphorimidate function is favoured by the trans orientation of the P=O bond with respect to the N-C4 bond. In the pyrrolidine ring moeity, the C2-C1-N-C4 atoms are nearly copolnar and the C3 atom is out of the plane by about 0.47 Å.  相似文献   

17.
Two coordination polymers (CPs) based on Keggin-type [SiW12O40]4 (SiW12), [Zn2(bpy)2(SiW12O40)(DMF)8solvent (1) and [Zn2(bpy)(SiW12O40)(DMA)8]·2DMA (2) (bpy = 4,4′-bipyridine, DMF?=?N,N′-dimethylformamide; DMA?=?N,N′-dimethylacetamide), have been solvo-thermally synthesized and characterized by single crystal X-ray diffraction, powder X-ray diffraction, IR spectra, elemental analyses and thermogravimetric analyses. Both 1 and 2 are synthesized under similar conditions except DMF and DMA were used as the solvents for 1 and 2, respectively. Structural studies reveal that the supramolecular framework of 1 contains pumpkin-like voids, while 2 has a non-porous supramolecular framework. These results show that solvents play an important role in construction of the POM-based CPs. The luminescent properties for 1 and 2 have also been investigated.  相似文献   

18.
The magnetic poly(ethylene glycol dimethacrylate-n-vinylimidazole) (Fe3O4@poly (EGDMA@VIM)) microspheres were prepared by suspension polymerization method using magnetite Fe3O4 nano-powder and the porosity, morphology, chemical composition and structure of the magnetic polymer microspheres were characterized. The specific surface area and swelling ratio of the Fe3O4@poly(EGDMA@VIM) microspheres were found to be 278.6?m2·g1 and 48%, respectively. The Fe3O4@poly(EGDMA@VIM) microspheres were used as an adsorbent for phenol removal. The effects of the parameters such as adsorbent dosage, temperature, pH and initial concentration of phenol solutions on the adsorption were investigated. The experimental adsorption equilibrium data obtained were fitted with Langmuir, Freundlich and Dubinin-Radushkevich isotherms and the pseudo-first-order, pseudo-second-order and intra–particle diffusion kinetic models. The adsorption equilibrium data agreed well with the Freundlich isotherm and the pseudo-second-order kinetic model. The maximum capacity of the Fe3O4@poly(EGDMA@VIM) microspheres was calculated to be 33.83?mg·g1 at 298?K and natural pH from Langmuir isotherm. The Fe3O4@poly(EGDMA@VIM) microspheres were found to be reusable for removal of phenol after desorption for several times. The result indicated that the Fe3O4@poly(EGDMA@VIM) microspheres are potential candidate for removal of phenol in wastewaters.  相似文献   

19.
Abstract

This review summarizes the data for over five hundred and fifty six-, seven- and eight-coordinate Cu(II) coordination compounds. The six-coordinate derivatives are mostly distorted tetragonal (elongation along a single C 4 axis). The seven-coordinate derivatives are only penta-gonal-bipyramidal with different degrees of distortion and the eight-coordinate complexes are dodecahedral. The most common ligands are O- and N-donors. There is a trend for the Cu-L distance to increase with covalent radius of the coordinated atom and also increasing coordination number. In general, Cu(II) compounds “prefer” a monoclinic class and are blue or green. Several relationships were found and discussed. The data are compared and discussed with those of four- and five-coordinate Cu(II) compounds.  相似文献   

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