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1.
有机-无机杂化钒氧配合物的合成研究越来越引起人们浓厚的兴趣,这是由于它新颖的结构和在催化、电化学、光化学、吸附、离子交换和磁性能方面具有潜在的应用前景犤1~8犦。功能体系的有机-无机杂化材料的构筑取决于反应物相互作用的本性。近年来,将有机胺分子作为结构导向剂引入无机骨架中,获得了一系列结构新颖的化合物犤9,10犦。它们通过共价键和(或)氢键自组装成零维、一维、二维和三维网络犤11,12犦。例如零维的犤(N2C6H14)2VO(PO3OH)4(B3O3OH)犦犤13犦、一维钒氧链犤Cu(dien)V2O6犦犤11犦,犤Cu(NH3)2V2O6犦犤14犦,犤狖Co(phen…  相似文献   

2.
有机-无机杂化太阳能电池因其结合了有机材料和无机材料各自的优势而引起了人们的广泛关注和研究. Cd基化合物纳米晶因其具有制备方法简单、尺寸及形貌可控、载流子迁移率高和稳定性好等优点而成为最早被研究的一类无机受体. 本文介绍了有机-无机杂化太阳能电池的结构及原理, 分析了影响有机-无机杂化太阳能电池效率的三个主要因素, 分别是开路电压(Voc)、短路电流(Jsc)和填充因子(FF). 从改善Cd基化合物纳米晶的合成方法, 增加Cd基化合物纳米晶和有机聚合物间的界面接触, 以及优化Cd基化合物纳米晶和有机聚合物所用溶剂和所占比例等方面阐述了近年来Cd基化合物纳米晶-有机聚合物杂化太阳能电池的研究进展. 并展望了Cd基化合物纳米晶-有机聚合物杂化太阳能电池的发展方向.  相似文献   

3.
K10H3[Gd(SiMo4W7O39)2]配合物界面扩渗Ce和Lu及其介导性能   总被引:17,自引:0,他引:17  
多金属氧酸盐由于具有独特的化学结构,作为特殊性能的功能材料已引起关注犤1~3犦。但其导电性和磁性差别较大,如何提高其导电性和磁性,进而制备出一类新型导电性和磁性材料,人们进行了探索。据文献报道犤4~6犦,多金属氧酸盐均是高质子导体,且电导率多数小于10-3S·cm-1,并随温度的升高,导电性降低,很难作为固体电解质在氢-氧燃料电池等器件上应用。本文从相关基础理论入手,采用气相法,首次研究了Ce,Lu通过固-气界面反应对K10H3犤Gd(SiMo4W7O39)2犦多金属氧酸盐簇合物的化学热扩渗。利用ICP,IR,…  相似文献   

4.
本文针对近五年来光功能稀土/无机/有机聚合物杂化材料的最新进展进行了评述,其重点着眼于高分子化合物作为构筑基元的发光稀土杂化材料体系的化学键组装.内容主要涉及稀土有机高分子杂化材料、配位键构筑的稀土/无机/有机高分子杂化材料、共价键构筑的稀土/无机/有机高分子杂化材料、自由基聚合构筑的稀土/无机/有机高分子杂化材料几个重要方面.主要结合我们自己的近期研究工作,通过系统总结来展现该领域的研究现状并提出未来展望.  相似文献   

5.
聚甲基三乙氧基硅烷/二氧化钛有机无机杂化材料的制备   总被引:1,自引:0,他引:1  
王华林  余锡宾 《应用化学》1998,15(5):101-103
溶胶-凝胶工艺是通过溶液在低温形成无机骨架,而广泛用于玻璃和陶瓷的制备[1~6].在此基础上发展了有机无机杂化材料(Ormosils),它是在连续无规的无机网络中掺杂有机组分,形成一种性能介于有机聚合物和无机聚合物之间的新型复合材料.文献报道的有机无...  相似文献   

6.
以苯乙烯-苯乙烯基膦酸共聚物、磷酸二氢钠作磷(膦)源,在温和的条件下,通过调节有机膦酸和无机磷酸的比例,合成了一系列不同化学计量比的聚(苯乙烯-苯乙烯基膦酸)-磷酸铝有机聚合物-无机杂化材料。通过FTIR、TG、N2吸附、XRD、SEM和TEM等表征手段对其进行了表征,并提出了其理想的结构模型。结果表明,这类杂化材料具有规则的层状结构和较高的热稳定性,作为催化剂载体具有潜在的应用价值。  相似文献   

7.
聚膦腈是一类主链由磷氮原子交替组成,每个磷原子带有两个有机官能团侧基的有机-无机杂化高分子,其化学结构强大的可设计性赋予了材料丰富的理化性能。作为生物学用途的聚膦腈材料,生物相容性、生物可降解性和功能化改性是实现其应用的关键因素。本文从数种功能化聚膦腈(如光致荧光、导电、聚膦腈-聚酯共聚物)的制备、聚膦腈的降解机理和降解行为调控,以及生物可降解聚膦腈作为组织工程支架材料、药物载体材料和基因转染材料等几个方面,较为全面地综述了聚膦腈生物医用高分子的研究进展。  相似文献   

8.
多面体低聚倍半硅氧烷(POSS)是一类具有纳米分子尺寸和有机-无机杂化结构的化合物。这种以无机Si—O—Si键组成的框架为核,外围被有机取代基所包围的特殊结构,具有独特的物理性质和化学反应性。采用物理或共聚的方法使其与其他聚合物复合,得到具有特殊功能的有机/无机纳米复合高分子材料,可用于诸多领域,近年来备受关注。本文在介绍POSS分子结构特点的基础上,详细阐述POSS聚合物的合成方法、特点和功能性,着重讨论了POSS在超疏水表面与抗结冰涂层、两亲聚合物、形状记忆材料中的应用及研究现状,并展望了功能性POSS聚合物的发展前景。  相似文献   

9.
近年来,多酸-有机复合材料的研究,受到了人们的广泛关注犤1犦。杂多化合物是一类含有氧桥的多核配合物,作为高质子酸,可以提供质子与有机给体形成多酸-有机复合物,这类质子化状态的复合物具有良好的光敏性,这种特性在光化学、氧化还原催化等方面显示出重要用途。聚碳酸酯是一种综合性能优良的光学材料,研究以其为基材的杂多酸-有机复合材料的基本性能,对聚碳酸酯的改性、增进对这类复合材料的理论研究以及拓宽聚碳酸酯的应用都有重要的实际意义,迄今为止,尚未见这方面的报道。本文以Keggin结构钼磷酸(简写为PMo12)和聚…  相似文献   

10.
近年来,溶胶-凝胶技术在制备无机-有机复合材料中的应用越来越广泛犤1~6犦。该方法既可以制得具有很好机械性能和光学均匀性的块体材料,也可以制得薄膜和粉体材料。有机光学活性物质在无机基质中的存在状态及其化学环境,有机分子之间及有机分子与无机基质之间的相互作用对材料的热稳定性、光学特性以及实际应用影响极大犤7~10犦。研究无机基质的微环境与有机光学活性分子之间的相互作用,对于复合材料的组成、性能、制备工艺的优化设计和实际应用至关重要。但是,目前有关这方面的系统研究报道很少。本文在硅溶胶中分别掺入了一…  相似文献   

11.
The Keggin-type cesium salt of transition metal-substituted phosphomolybdates, Cs5[PCo(H2O)Mo11O39]?·?6H2O (1) and Cs5[PMn(H2O)Mo11O39]?·?6H2O (2), were synthesized from commercially available H3PMo12O40. The compounds were characterized by thermal, structural, and spectroscopic techniques. X-ray structural analysis reveals that, in these isostructural disordered compounds, the transition metal (Co/Mn) and Mo atoms are distributed over 12 positions. The presence of Co/Mn atoms was confirmed by powder XRD, FT-IR, DR-UV-Vis, ESR, and 31P NMR studies.  相似文献   

12.
In this paper, the synthesis, the characterization and the scintillation properties of LuPO4 doped, with several concentrations of Ce3+, Eu3+ and Tb3+ ions, are presented. These materials have been synthesized by sol-gel process. The purity of powders has been verified by X-Ray diffraction and the results confirm the xenotime structure of all the materials. A thermogravimetric analysis allows the obtention of informations on the crystallisation of LuPO4 and the study of its evolution from the amorphous to crystalline form. The morphology of the powders has been studied by Scanning Electron Microscopy and shows that the powders are constituted of small particles with narrow size distribution. Optical properties have been studied in order to determine the scintillation performances of these materials. The optima are obtained for Ce3+, Eu3+ and Tb3+ concentration of respectively 0.1, 10 and 5% with high scintillation yields. This study thus confirms the potentialities of these materials as scintillators.  相似文献   

13.
Four polyaniline hybrid materials doped with iron-substituted silicotungstate isomers α,?β i - K5?n H n [SiW11Fe(H2O)O39]?·?xH2O (βi?=?β1, β2, β3) were prepared. The materials were characterized by elemental analysis, IR spectra, UV-Vis spectra, scanning electron microscopy (SEM), TG-DTA and X-ray diffraction (XRD). The conductivity and fluorescence were determined and thermal stability was studied. The UV-Vis, IR and XRD results confirm the existence of Keggin anions. Thermal analysis indicates that SiW11Fe/PANI has better thermal stability. The images of scanning electron microscopy (SEM) show that the materials are microporous. The materials exhibit excellent proton conductivity of 8.5?×?10?2?S?cm?1 at room temperature (20°C). The spectral data indicate that polyaniline doped with α, βi-SiW11Fe have similar fluorescence, λem?=?418–470?nm, and emit blue light.  相似文献   

14.
Highly active and non-toxic ZnO incorporated with zinc silicate (zinc silicate/ZnO) nanocomposites are synthesized via a simple and low-cost hydrothermal method followed by heat treatment. Different molar ratios from Si to Zn [1:20], [1:10], [1:8] and [1:6] are used to prepare different zinc silicate/ZnO nano composite materials which are assigned to ZS1, ZS2, ZS3 and ZS4 samples, respectively. The effect of calcination times and temperatures have been investigated on the crystallographic and morphological properties of the synthesized nano composite materials. The XRD analysis show that at very low molar ratios, zincite (ZnO) is the most predominant phase. However, at higher molar ratios, there are two phases coexist; hemimorphite (Zn4Si4O7) and zincite. The TEM images show a uniform nanoplate-like shaped morphology from ZnO with well dispersed Zn2SiO4 nanoparticles. The SBET is remarkably increased from 18.14 to 176.5 m2.g−1 by calcination up to 400 °C and then decreased to 72.2 m2. g−1 by further increasing in the calcinations temp up to 1,000 °C. The bio and photocatalytic activities of the composite nanomaterials have been investigated. Compared with the pure ZnO, the nano composites have been demonstrated as better photocatalysts for the degradation of Levafex golden yellow (LGY) dye as a model of organic dye pollutant under simulated sunlight irradiation. Moreover, the nano composites were evidenced to possess better and non-toxic antitumor activity towards hepatocellular carcinoma cell lines with (IC50 = 11.2 μg.ml−1 and LD50 ˃ 50 mg. Kg−1).  相似文献   

15.
Precipitate formation between phosphotungstic acid and crown ethers is a general phenomenon, producing solids with selective ion exchange behavior for the alkali metal ions. Distribution coefficients for Li+, Na+, K+, and Cs+ were measured for a series of these precipitates with different crown ethers. The sorption data are more complicated than for the corresponding phosphomolybdates and indicate a variability in the number of exchangeable sites with H+ and M+ concentration. The crown ether used markedly affects the cation selectivity of the phosphotungstate precipitates.  相似文献   

16.
Ce3 +-doped LuBO3 powders have been prepared by a sol–gel process with Ce3 + concentration varying between 0 and 5 mol%. These materials have been analyzed by X-ray Diffraction and Fourier Transform Infra Red Spectroscopy. The results confirm that all the materials have the vaterite type even if the calcination has been performed at 800°C. Furthermore, doping with Ce3 + ions does not affect the structure and the vaterite is preserved even at 5% doping. Scanning Electron Microscopy showed a very uniform morphology with small spherical grains with a narrow size distribution. Optical properties have been studied to confirm the effective substitution of Ce3 + for Lu3 + ions and to determine the materials scintillation performances. It has been shown that 0.5% is the optimum Ce(III) concentration in term of scintillation yield with an X-ray conversion yield equivalent to that of standard BGO (Bi4Ge3O12). The afterglow has also been measured and confirms the potential of these materials as scintillators.  相似文献   

17.
Two series of Eu3+-doped homologous-SBA-15 materials (abbreviated as MPTMS-SBA-15: Eu3+ and CTMS-SBA-15: Eu3+) have been synthesized by a hydrolysis-controlled technology, in which two novel silane crosslinking reagents (3-(methacryloyloxy) propyltrimethoxysilane (MPTMS) and 3-(chloropropyl) trimethoxysilane (CTMS)) are used as silicate precursor instead of traditional tetraethoxysilane (TEOS). It can be found that the different silicate precursors with different functional groups have influence on the physical properties of the corresponding homologous materials. In comparison to the pure SBA-15, the BET surface area and pore size of the modified mesoporous materials have been changed. Finally, the characteristic luminescence is observed for the 5D0 → 7FJ (J = 0, 1, 2) transition of Eu3+ ion, suggesting that these kind of homologous-SBA-15 materials are potential host for the luminescence of Eu3+, whose excitation energy can be quenched by Eu3+ to some extent.  相似文献   

18.
Copolymers and homopolymers containing silicon atoms connected to three and four other silicon atoms have been prepared and characterized. We report the first evidence of dendritic polymers with silicon backbones. Copolymers made from RSiCl3 and R1R2SiCl2 resemble hybrid materials of polysilyne and polysilanes. Polymers, which contain tetrasilyl-substituted Si atoms, [(SiMe2)4Si]n and (Si)m(Me2Si)n, have also been synthesized. These molecules appear to be the first hyperbranched polymers, which have applications based on their electronic properties. The properties of these molecules fit into the hierarchy of 1-D to 3-D topologies known for Si materials.  相似文献   

19.
Two new solid hybrid molecular materials [PyPS]H6P2W17VO62 and [PyPS]H8P2W15V3O62 have been synthesized from 1-(3-sulfonic group) propyl-pyridine ionic liquid cation and tungstovanadophosphoric anion with the Dawson structure. They were characterized by element analysis, impedance spectroscopy (IS), IR- and UV-spectroscopy. The formation of the hybrid molecular compounds with the Dawson structure was showed. Ion conductivity of [PyPS]H6P2W17VO62 and [PyPS]H8P2W15V3O62 are 3.99 × 10?3 and 7.37 × 10?3 S cm?1 at 18°C and 55% relative humidity respectively. The activation energies of proton conductivity are 28.2 and 26.7 kJ mol?1 respectively.  相似文献   

20.
In this study, a series of compounds based on Dawson-type phosphomolybdates, H3(C6NO2H6)2[K(H2O)3(C6NO2H5)3][P2Mo18O62] ? 5.5H2O (1), (C6NO2H6)6[Ln(H2O)7(C6NO2H5)2]2[P2Mo18O62]2·13.5H2O (Ln = Ce (2), La (3)) have been synthesized and characterized by elemental analysis, IR and UV-Vis spectroscopy methods, TG analysis, and single-crystal X-ray diffraction. Compound 1 consists of [P2Mo18O62]6? building units joined by potassium-pyridine-3-carboxylic acid complexes, resulting in a wavelike polyoxometalate (POM) chain, which further interacts with each other via intermolecular interactions to form a 3-D supramolecular channel framework containing guest water molecules. Compounds 2 and 3 possess a 3-D supramolecular framework with 1-D tunnel constructed from [P2Mo18O62]6? and mononuclear lanthanide coordination complex fragments. To the best of our knowledge, 1 not only represents the first example of 1-D hybrid assembly based on Dawson-type phosphomolybdate, but also the first hybrid compound constructed from Dawson-type POMs and alkali–metal coordination complex fragments.  相似文献   

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