钼磷酸和2-吡啶-偶氮-2萘酚电荷转移配合物的合成、表征及性质研究

杂多化合物具有很强的接受电子能力,是一类优秀的受体分子,它可以与有机分子以氢键或配位键作用形成电荷转移配合物。由于这类配合物具有特殊的光、电、磁性质在催化、功能材料及药物化学等领域受到研究者的广泛关注[1]。有大量文献报道了杂多酸作为电子受体与有机给体相结合形成电子给一受型配合物,并在性能方面进行了探讨[2-3]。为了考察有机配体的位阻效应对配合物形成的影响,我们选择体积大,含有偶氨基及共轭π键的2-吡啶- 偶氮-2-萘酚（简写为PAN）为电子给体,12-钼磷酸（简写为PMo12）为电子受体,制备了新型标题化合物,并对…     

双长链烷基Dawson结构钼磷酸复合薄膜的制备、结构及光致变色性质

近年来 ,无机 -有机复合材料由于其独特的结构和特殊的光、电和磁功能特性而引起科研工作者的广泛关注 [1,2 ] .杂多化合物为均一的无机多聚物 ,具有笼状结构 ,结构中均有 M3O13三金属氧簇 ,能够接受电子生成杂多蓝或杂多棕 ,加之其在水和有机溶剂中的溶解性和稳定性 ,使其在光电变色材料领域中具有潜在的应用价值 [3～ 5] .但这类化合物难于加工成实际应用的器件 ,因而限制了其进一步的应用 .利用有机组分调控的超分子自组装技术可构建光致变色同多酸或杂多酸纳米薄膜材料 ,从而为开发变色响应快、稳定性好、变色可调控的新型光电变色高密…     

含铕配合物的有机电致发光器件的光伏效应

自从1986年Ｔａｎｇ发表了双层有机电致发光器件有光伏效应[1]以来,人们就一直对有机器件的光伏效应有浓厚的兴趣,特别是近年来有大量的文章报道有机器件的光伏效应。在这些报道中,使用材料中有用聚苯乙炔及其衍生物的[2,3],有用Ｃ60做电子受体的[4],但这些研究都与电致发光无关,仅研究了光电转换特性,我们研究组首次报道了电子给体发光,电子受体稀土配合物不发光的有机光伏器件[5]。本文就是在此基础上进一步研究铕配合物ＯＥＬ器件的光伏效应。铕配合物ＯＥＬ器件不仅仅有利于利用配体三重态能量、提高能量转换效率的潜力,而且中心离…     

[Ni(NN)(SS)]混配配合物的合成与性质

多硫 1,2-二硫醇烯配合物如 [M(dmit)2]n－、 [M(dddt)2]n－、 [M(pddt)2]n－等作为分子导体已有广泛的研究 [1,2]。多硫 1, 2-二硫醇烯 [M(NN)(SS)]型混配配合物,既含有可作为电子给体的 1,2-二硫醇烯配体,又含有可作为电子受体的二亚胺（ diimine）配体,由于分子内的配体到配体的电荷转移（ LLCT）作用,使得电中性的平面型分子中,两种配体处于极化状态,其新奇的分子结构,以及由此而来的光电磁等性质,也格外引人关注 [3]。文献报道这类配合物在适当的激发波长作用下可被光氧化并发出强光 [4]。另一方面,由于配体与配体间的…     

用高浓度杂多酸溶液催化苯甲醚与乙酸酐的酰化反应

芳香化合物经Friedel-Crafts酰化反应制备药物和香料中间体芳香酮是近年来人们感兴趣的课题^[1-4]。用于该反应的传统催化剂是Lewis酸金属氯化物。由于反应过程中催化剂可与酰化试剂羧基产物形成配合物,因而催化剂用量大,且所形成的配合物水解后产生大量废液。为了减少环境污染,人们已成功地用分子筛催化剂代替传统催化剂催化芳香化合物的酰化反应^[5-7]。其中包括用分子筛催化各种芳香化合物与乙酸酐的酰化反应^[8]。我们已经研究了用杂多酸－乙酸浓溶液催化异丁烷与丁烯的烷基化反应^[9,10],以及烯烃与羧酸的直接酯化反应^[11]。本文将报道杂多酸－乙酸浓溶液对苯甲醚与乙酸酐酰化反应的催化活性。     

卟啉-二芳基乙烯分子及其金属配合物的合成与光致变色特性

以苯甲醛和吡咯为初始原料,经多步反应合成了5-[2,3-双(2,4,5-三甲基-3-噻吩基)马来酰亚胺-N-苯基]-10,15,20-三苯基卟啉(TPPMA)及其金属锌配合物(ZnTPPMA)与铜配合物(CuTPPMA),通过IR,MS,1H NMR和13C NMR确认了化合物的结构,并利用UV-Vis光谱探讨了化合物的光致变色性能.实验结果表明,无论在聚乙烯醇缩丁醛(PVB)膜还是在溶液中,TPPMA在254 nm紫外光照射下,没有光致变色现象,而在254和650 nm的光照下其金属配合物CuTPPMA和ZnTPPMA在溶液及PVB膜中皆可以发生可逆的光致变色反应.     

新型高分子-多酸电荷转移配合物的合成与表征

以Keggin结构的磷钨酸、硅钨酸为电子受体,高分子聚乙烯亚胺(PEI)为电子给体,合成了两种新型电荷转移配合物CH2CH2N(CH2CH2NH2)CH2CH2NHCH2CH2NH2.1H3PW12O40·10.6H2O(配合物Ⅰ)和CH2CH2N(CH2CH2NH2)CH2CH2NHCH2CH2NH1.3H4SiW12O40·8.3H2O(配合物Ⅱ)。采用元素分析、红外光谱和紫外光谱进行表征,并用扫描电镜观察产物形貌及其聚集形态。结果表明有机给体与杂多酸间有较强的相互作用。光致变色后,配合物中有机阳离子和杂多阴离子之间发生了电荷转移,导致杂多阴离子中WⅥ还原为WⅤ,同时有机阳离子被氧化,且该配合物有很高的耐溶剂性。     

两种双核稀土配合物的光致变色和光磁效应

利用光诱导电子转移机理和配位驱动组装策略探索室温光磁效应材料的合成. 通过组装稀土硝酸盐与1,10-菲罗啉(phen)获得2种同构双核稀土配合物[Ln₂(NO₃)₆(phen)₂](1: Ln=Gd; 2: Ln=Dy). 由于具有电子给体-受体结构特征, 目标产物在光照后发生电子转移, 电子由硝酸根的氧原子转移到phen的氮原子, 进而产生光生自由基并发生肉眼可见的颜色变化. 除光致变色外, 配合物1和2在室温下具有光磁效应. 本研究为构筑室温光致变色和光磁效应杂化材料提供了一种通用方法: 配位组装顺磁金属盐与菲罗啉衍生物.     

Keggin结构钨磷酸/聚乙烯吡咯烷酮复合膜的制备和光致变色性质研究

近年来,由于无机－有机复合材料具有潜在的应用前景和特殊性能,尤其是光致变色性能,引起研究者们的广泛兴趣^[1-3],以杂多化合物为多核配合物,通过化合键或氢键作用与高分子底物结合,形成电荷转移物质,可以大大提高复合材料的化学和物理性能。目前,这一领域的研究在国外已经成为热点^[4-7]。本文以Keggin结构钨磷酸和聚乙烯吡咯烷酮为原料,报道了该类复合物的合成、表征及光致变色性质。     

新型电荷转移配合物的合成与表征

近年来有关多金属氧酸盐与有机化合物间电荷转移配合物的光化学和光致变色过程的研究日趋活跃［１,２］,但迄今这类电荷转移配合物中的多金属氧酸盐基本上为Ｌｉｎｄｑｕｉｓｔ结构的同多酸或Ｋｅｇｇｉｎ结构的杂多酸,有机给体则基本上限于有机胺及其衍生物（如酰胺）...     

双偶极半菁衍生物／H4SiW12O40自组装多层膜的研究

通过交替吸附H_4SiW_(12)O_(40)和双偶极半菁衍生物制备了一个新颖的无机- 有机杂化自组装多层膜。紫外可见光谱和X射线衍射研究证实了半菁衍生物 /H_4SiW_(12)O_(40)多层膜可被均匀沉积厚达至少12层，具有平均膜厚5.3nm(半菁 阳离子层加SiW_(12)O_(40)~(4-)层)的二维有序结构，膜中半菁衍生物与H_4SiW_ (12)O_(40)间发生了较强的电荷转移作用。循环伏安研究表明，薄膜具有较好的电 化学活性。     

镶嵌钨硅酸的新型有机-无机纳米复合薄膜的制备及光致变色性能研究

将超分子自组装技术与Sol-gel过程相结合,制备了镶嵌Keggin结构钨硅酸的MAAM/VTEOS/TEOS纳米复合薄膜,并采用IR,XRD和TG-DSC等方法对薄膜进行了结构表征.在复合薄膜光照变蓝后,通过UV-Vis和ESR光谱对薄膜的光致变色性能及其机理进行了研究.结果表明,钨硅酸在复合网络中仍保持Keggin结构,与有机-无机复合基体中的-NH₂通过氢键发生强烈的相互作用,经紫外光照后发生电荷转移,[SiW₁₂O₄0]₄^-被还原为[SiW₁₂O₄0]₅^-,同时产生氨基自由基.褪色过程则与氧气存在与否有关,实验结果表明,该薄膜具有良好的光致变色性能,对光有较快的响应恢复速度和良好的可逆重复性.     

H4SiW12O40和双偶极Ru(II)配合物形成的静电自组装多层膜

制备了含有H4SiW12O40和双偶极Ru(II)配合物交替层的一个新颖静电自组装多层膜.用紫外可见光谱、循环伏安学、原子力显微镜对薄膜进行了表征和性质研究.结果表明膜沉积平稳、均匀,所制得的薄膜具有较好的电化学活性.AFM图像表明钌(II)配合物和H4SiW12O40层具有明显不同的微区结构.     

Hydrothermal Synthesis and Crystal Structure of a Polyoxometalate- based Complex [Cu^I（phen）2]4（SiW12O40）

A new hybrid polyoxometalate-based complex, [Cu^I（phen）214（SiW12O40） （phen = 1,10-phenanthroline）, has been synthesized by hydrothermal method and characterized with the aid of elemental analysis, IR, UV spectra and thermal analysis studies. The result of X-ray crystallography analysis exhibits that the title compound crystallizes in the orthorhombic space group P212121, and the formula is C96H64N16Cu4SiW12O40. Crystal data： a = 18.3574（14）, b = 21.1952（16）, c = 27.992（2）A, Mr = 4570.08, V = 10891.4（14）A^3, Z = 4, Dc = 2.787 g/cm^3,μ = 13.478 mm^-1, R = 0.0364, wR = 0.0638 （I 〉 2σ（I）） and F（000） = 8360. The complex consists of one α-Keggin anion [SIW12O40]^4- and four discrete [Cu^I（phen）2]^＋ cations. The valence sum calculations for the Cu atoms suggest that all four Cu atoms are in the ＋1 oxidation state.     

Polyoxometalate-stabilized Pt nanoparticles and their electrocatalytic activities

The synthesis of long-term stable polyoxometalate (POM)-stabilized Pt nanoparticles (NPs) is described here. By means of controlled bulk electrolysis, the reduced POM anions, SiW(12)O(40)(4-) (or SiW(12)) and H(2)W(12)O(40)(6-) (or H(2)W(12)), respectively, served the dual role of reductant and protecting/stabilizing ligand for the Pt NPs. Transmission electron microscopy (TEM) images confirmed the formation of 3 to 4 nm sized Pt NPs, which coincidently was in the same size range of the commercial Pt black that was used as a reference. Elemental XPS analyses showed W/Pt ratios of 0.12 for the SiW(12)- and 0.18 for the H(2)W(12)-stabilized Pt NPs, but found no evidence of the presence of Cl(-) anion in the samples. Controlled electrochemical (EC), UV-Vis, and IR data provided unambiguous evidence for the structural integrity of the POM anions on the Pt NP surface. CO stripping, methanol oxidation reaction (MOR), and oxygen reduction reaction (ORR) were used to assess their electrocatalytic activities. It was found that both SiW(12)- and H(2)W(12)-stabilized Pt NPs showed enhanced activities in MOR and ORR as compared to that of Pt black, with the latter having higher enhancement. These observations clearly demonstrated that the stabilizing POM anions have a profound influence on the electrocatalytic activity of the underlying Pt NPs.     

含硅多金属氧酸盐的抑菌作用

本文按文献方法合成了α-1,2,3-K6H[SiW9V3O40]、α-1,2-K6[SiW10V2O40]和α-K5[SiW11VO40](以下分别简写为α-SiW9V3,α-SiW10V2,α-SiW11V)3种多金属氧酸盐,并通过紫外和红外光谱对3种多金属氧酸盐化合物结构进行了表征。利用纸片法研究了3种钒取代的硅钨酸盐及硅钨酸（H4SiW12O40?xH2O,简写为SiW12）对大肠杆菌、枯草芽孢杆菌、酵母菌、黑曲霉和青霉的抑菌活性。结果表明：4种物质对大肠杆菌、枯草芽孢杆菌、酵母菌和黑曲霉均有不同程度的抑菌效果,但对青霉的抑菌效果较差。由于引起果蔬腐败的微生物主要有细菌、杆菌、霉菌和酵母菌等,本实验将为多金属氧酸盐作为广谱高效果蔬保鲜剂提供理论依据。     

A Novel Optical Complex between an Organic Substrate and a Polyoxometalate. Crystal and Molecular Structure of alpha-H(4)SiW(12)O(40).4HMPA.2H(2)O (HMPA = Hexamethylphosphoramide)

A solvated complex of alpha-H(4)SiW(12)O(40).4HMPA.2H(2)O composed the heteropolytungstate alpha-H(4)SiW(12)O(40) and the organic substrate hexamethylphosphoramide (HMPA) has been synthesised, purified, and characterized. The electronic spectra (lambda = 220-500 nm) as well as the (1)H NMR spectra for the title compound dissolved in CD(3)CN establish that this complex dissociates into free SiW(12)O(40)(4)(-) and HMPA moieties in solution unless the organic substrate HMPA is present in very high concentrations. The solid reflectance electronic spectra and IR spectra indicate that there is interaction between the alpha-H(4)SiW(12)O(40) and the organic substrate. The complex has no photosensitivity under irradiation of sunlight, but under the near-UV light result in a charge transfer by oxidation of the HMPA and the reduction of the polyoxometalate. Light yellow polyhedrons of the title compound crystallize from the aqueous solvent of acetonitrile and aqueous solution as the formula of alpha-H(4)SiW(12)O(40).4HMPA.2H(2)O in the monoclinic, space group P2(1). The unit cell has a = 12.791(3) ?, b = 22.103(6) ?, c = 15.532(4) ?, beta = 102.860(10) degrees, and Z = 2. From the bond-valence parameters, it was found that the four hydrogen atoms of the polyoxometalate were combined with the N atoms of the four HMPA respectively. The title compound shows a certain second-order and third-order nonlinear optical response of I(2)(omega) = 0.7I(2)(omega)(KDP) and chi((3)) = 2.63 x 10(-)(11) esu, respectively.     

Si取代Keggin型多酸催化光解水产氢机理

本文采用DFT和TD-DFT方法研究了Keggin型多酸[SiW12O40]4-光催化劈裂水产氢气机理。计算结果显示反应主要包括四个步骤：(i) 光激发,(ii) 电荷转移和生成单电子还原(OER)中间体,(iii) 生成双电子还原(TER)中间体,(iv)氢气从多酸表面解离和催化剂重生。当第一个电子从甲醇转移到多酸后,后续反应存在均为热力学上有利的放热途径,并推动第二个电子从甲醇自由基,H[SiW12O40]4-或[SiW12O40]5-转移到OER中间体H[SiW12O40]4-或[SiW12O40]5-生成TER中间体[SiW12O40]6-,H[SiW12O40]5-或H2[SiW12O40]4-,并伴随着H2产生。耦合的电子和质子转移路径在能量上最有利。甲醇和水分子的参与有利于H2产生。多酸在整个催化循环中,扮演了光敏剂、催化剂、电子的受体和给体。     

Inorganic-organic hybrid materials with different dimensions constructed from copper-fluconazole metal-organic units and Keggin polyanion clusters

Inorganic-organic hybrid materials based on Keggin polyoxometalate building blocks combined with Cu(II)/Cu(I) and flexible fluconazole ligand [1-(2,4-difluorophenyl)-1,1-bis[(1H-1,2,4-triazol-1-yl)methyl]methanol] (Hfcz) have been obtained by hydrothermal methods, namely, [Cu(II)(2)(Hfcz)(4)(SiW(12)O(40))].3H(2)O (1), [Cu(II)(4)(fcz)(4)(H(2)O)(4)(SiMo(12)O(40))].6H(2)O (2), [Cu(II)(2)(fcz)(2)][Cu(II)(4)(fcz)(4)(SiW(12)O(40))][Cu(II)(2)(fcz)(2)(H(2)O)(2)(SiW(12)O(40))].6H(2)O (3), (Et(3)NH)(2)[Cu(I)(2)(Hfcz)(2)(SiW(12)O(40))].2H(2)O (4), (Et(3)NH)(2)[Cu(I)(2)(Hfcz)(2)(SiW(12)O(40))].H(2)O (5) and [Cu(I)(4)(Hfcz)(4)(SiMo(12)O(40))] (6). Their structures have been determined by single-crystal X-ray diffraction analyses, and the compounds are further characterized by elemental analyses, IR spectra and thermogravimetric (TG) analyses. In 1, Cu(II) cations are bridged by fluconazole ligands to form a 3D lvt coordination polymeric network, which is connected by (SiW(12)O(40))(4-) anions to form a complicated 3D (4,6)-connected framework with the topology of (4(2).6(4))(4(6).6(7).8(2))(2). In 2, two fcz(-) anions chelate two Cu(2+) cations to form a [Cu(fcz)](2)(2+) dimer, which is bridged by (SiW(12)O(40))(4-) polyanions to generate a 2D (4,4) grid. Compound 3 is formed by three types of co-crystallizing subunits including a dimer [Cu(fcz)](2)(2+), a dumbbell molecule [Cu(4)(fcz)(4)(SiW(12)O(40))] and an infinite chain {[Cu(2)(fcz)(2)(H(2)O)(2)(SiW(12)O(40))](2-)}(infinity). In compounds 4 and 5, Hfcz ligands link Cu(+) cations to generate 1D coordination polymeric units, and (SiW(12)O(40))(4-) polyanions connect these metal-organic units to form two types of (6(3)) sheets which are topological isomerism. In compound 6, (SiMo(12)O(40))(4-) polyanions fixed in Cu(I)-Hfcz square rings are further extended into a 2D sheet via linking Cu(I) atoms of different rings. By carefully inspection of the structures of 1-6, it is believed that various transition-metal organic units and Keggin polyanions with different coordination modes are important for the formation of the different structures. In addition, electrochemical behaviors of compounds 1, 2, 5 and 6 have been investigated.     

Synthesis, Crystal Structure and Photocatalytic Properties of a Supramolecular Assembly Based on Keggin Polyoxotungstate

A new supramolecular compound (4,4'-bipyH)4[SiW12O40](4,4'-bipy) (4,4'-bipy = 4,4'-bipyridine) was synthesized hydrothermally and characterized by single-crystal X-ray diffraction and IR spectrum. The crystallography analysis for the title compound reveals that the crystal crystallizes in monoclinic, space group C2/m with a = 22.2767(12), b = 21.1879(11), c = 15.6942(8) , β = 97.068(3)°, V = 7351.3(7) 3, C50H44N10O40SiW12, Mr = 3659.24, Z = 4, Dc = 3.306 g/cm3, F(000) = 6544, GOOF = 1.137, R = 0.0577 and wR = 0.1579. The title compound consists of a discrete Keggin-type [SiW12O40]4- anion, one 4,4'-bipy and four protonated (4,4'-bipyH)+ cations. The [SiW12O40]4- anion and protonated 4,4'-bipy are connected to form a supramolecular structure by hydrogen bonds. Meanwhile, the title compound exhibits good photocatalytic activity for color degradation of Rhodamine-B dye solution under visible-light irradiation.