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81.
《Journal of Coordination Chemistry》2012,65(9):1529-1537
A new Keggin-type polyoxometalate-based inorganic–organic hybrid, [Cu(H2O)2(daphen)]2[SiW12O40]·9H2O (1) (daphen?=?5,6-diamino-1,10-phenanthroline), was hydrothermally synthesized, and characterized by single-crystal X-ray diffraction, elemental analysis, infrared spectroscopy, fluorescence spectra, and thermal analysis. Single-crystal X-ray diffraction analysis reveals that in 1, [SiW12O40]4? is a tetradentate ligand with its four terminal oxygens coordinating to four Cu(II)–daphen fragments to form a 2D sheet with (4,4) topology. On the basis of the insolubility of 1 in water and common organic solvent and its reversible multielectron redox processes, 1 was used to fabricate a bulk-modified carbon paste electrode (1-CPE) by direct mixing. Electrochemistry indicated that 1-CPE is stable over hundreds of cycles and possessed electrocatalytic activity toward the reduction reactions of nitrite. 相似文献
82.
溶胶-凝胶法合成有机/无机杂化材料进展——1.组分间以化学键作用的有机/无机杂化材料 总被引:5,自引:0,他引:5
介绍了溶胶-凝胶法(Sol-gel process)制备组分间以化学键作用的有机/无机杂化材料的基本情况,根据合成方法进行分类,并指出其发展趋势。 相似文献
83.
聚酰亚胺-二氧化硅杂化膜的制备及表征 总被引:21,自引:0,他引:21
采用溶胶-凝胶法制备了两类具有不同二氧化硅含量的聚酰亚胺-二氧化硅(PI-SiO2)杂化膜,并用SEM,IR,TG-DTA,氮吸附和气体渗透性能测试等手段对该膜材料的表面形貌、结构、热性能、孔径分布和气体渗透性能进行了表征.结果表明,PI-SiO2膜材料中SiO2粒子的分散良好,与有机相之间存在着分相和键联;膜材料的玻璃化温度θg均随SiO2含量的增加而升高.相比之下,在酸性条件下制备的T系列杂化膜比在碱性条件下合成的S系列杂化膜对θg的影响更大一些;杂化膜具有较好的气体渗透性能和亲水性能,其H2O/N2和H2O/CH4的分离系数远大于努森扩散的理论值. 相似文献
84.
We have recently published three papers (P. Wagner et al., Phys. Chem. 103 (1999) 8245; S. Inagaki et al., J. Am. Chem. Soc. 121 (1999) 9611; A. Carlsson et al., J. Electron Microscopy 48 (1999) 795) that herald a new approach to structural solutions in micro- and mesoporous solid state materials. Among these materials are the first hybrid inorganic–organic mesoporous materials, synthesized using the organosilane compound 1,2-bis(trimethoxysilyl) ethane (BTME). Both organic and inorganic fragments are distributed completely uniformly at the molecular scale in the mesoporous walls. Two distinct phases with two- and three-dimensional (2d- and 3d-) hexagonal periodic pore-arrangements have been detected. We have also recently reported another new cubic hybrid phase with a decaoctahedral crystal morphology. Two new approaches for solving the structures of porous materials from either electron diffraction (ED) or high-resolution electron microscope (HREM) observations have also been developed. The former was successfully applied by combining direct methods for structural analysis of the new microporous crystal SSZ-48, which crystallizes only in very small crystals. The latter technique was applied to 3d-structural analysis of the mesoporous material MCM-48. The structure solutions, in the latter case, are obtained uniquely without preassumed models or parameterization, unlike previous reports. 相似文献
85.
Signorini Raffaella Meneghetti Moreno Bozio Renato Brusatin Giovanna Innocenzi Plinio Guglielmi Massimo Negra Federico Della 《Journal of Sol-Gel Science and Technology》2001,22(3):245-253
Hybrid organic-inorganic materials are investigated as suitable materials for inclusion of fullerene derivatives and for fabrication of laser protection devices. A specific synthesis has been developed in order to optimize non-linear optical performances of fullerene derivatives. 3-glicydoxypropyltrymethoxysilane has been used as an inorganic and organic network former to obtain the host material. The sol-gel synthesis consists of the hydrolysis and condensation in acidic conditions of the inorganic network. Epoxy polymerization has been achieved by using zirconium or BF3 alkoxides precursors. Bulk and multilayer materials doped with a fullerene derivative have been fabricated. They show good optical requirements: high fullerenes concentration, high microstructural homogeneity, high laser damage threshold and high optical limiting efficiency. Optical limiting (OL) mechanisms have been investigated. The most effective in the sol-gel materials is the reverse saturable absorption (RSA) one. However, different mechanisms, like non-linear (NL) scattering and NL refraction contribute to a different extent. Open- and closed-aperture OL and z-scan measurements on sol-gel samples show the contribution of NL scattering and NL refraction at 690 nm. Laser damage threshold has been characterized as a function of the structure of the samples and of the optical configurations (f/66 and f/5). 相似文献
86.
Jian Guo DENG Xiao Bin DING Yu Xing PENG* Albert S. C. CHAN* Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu Open Laboratory of Chirotechnology Department of Applied Biology Chemical Technology 《中国化学快报》2001,(11)
Among various conducting polymers, polyaniline (PANI) is a unique and promising candidate for practical applications because it is not only highly stable in air and in some solvents, but also exhibits dramatic changes in its electronic structure and physical properties in protoactivate state1,2,3. The carbon nanotubes (CNTs) have been proven to possess exotic properties, such as high mechanical strength, flexibility and electric conductivity. The study of carbon-based nanostructures and ma… 相似文献
87.
Doping silver nanoparticles in AOT lyotropic lamellar phases 总被引:1,自引:0,他引:1
The organic lyotropic liquid crystal with long-range structural order is used as template to assemble inorganic/organic hybrid by doping pre-fabricated Ag nanoparticles. The lamellar hybrid with both hydrophilic and hydrophobic particles doped simultaneously is realized for the first time. The change of template structure after doping and the stability origin of dual-doped system are characterized by small angle X-ray scattering and polarized optical microscopy. Results show that the interaction and space matching between surfactant bilayers and doped particles are key factors to obtain stable hybrid. 相似文献
88.
Scalable Preparation of Photochromic Composite Foils with Excellent Reversibility for Light Printing 下载免费PDF全文
Photochromic inks for repeatable light‐printed media have attracted increasing attention owing to the fact that they may be widely applied to reduce the consumption of papers and plastics and conserve the environment. Therefore, it is of practical significance to develop convenient photochromic inks with a low cost and on a large scale. In this study, a simple one‐step hydrothermal route was used to prepare tungsten trioxide (WO3) nanoparticles, which were further used to make photochromic inks and transparent photochromic films. The obtained transparent photochromic film could rapidly respond to UV light within tens of seconds, then return to its initial state, with different recovery times at different temperatures, and also exhibit good reversible coloration–bleaching effect. A typical polyethylene terephthalate (PET) foil coated with the photochromic ink could also be repeatedly printed with various patterns and displayed excellent rewritable performance over tens of cycles. This study proposes a simple method for widespread applications of WO3‐based photochromic inks. 相似文献
89.
Hierarchical MoS2@TiO2 Heterojunctions for Enhanced Photocatalytic Performance and Electrocatalytic Hydrogen Evolution 下载免费PDF全文
Yu Dong Sheng‐You Chen Yi Lu Yu‐Xuan Xiao Jie Hu Si‐Ming Wu Dr. Zhao Deng Prof. Ge Tian Prof. Gang‐Gang Chang Prof. Jing Li Prof. Silvia Lenaerts Prof. Christoph Janiak Prof. Xiao‐Yu Yang Prof. Bao‐Lian Su 《化学:亚洲杂志》2018,13(12):1609-1615
Hierarchical MoS2@TiO2 heterojunctions were synthesized through a one‐step hydrothermal method by using protonic titanate nanosheets as the precursor. The TiO2 nanosheets prevent the aggregation of MoS2 and promote the carrier transfer efficiency, and thus enhance the photocatalytic and electrocatalytic activity of the nanostructured MoS2. The obtained MoS2@TiO2 has significantly enhanced photocatalytic activity in the degradation of rhodamine B (over 5.2 times compared with pure MoS2) and acetone (over 2.8 times compared with pure MoS2). MoS2@TiO2 is also beneficial for electrocatalytic hydrogen evolution (26 times compared with pure MoS2, based on the cathodic current density). This work offers a promising way to prevent the self‐aggregation of MoS2 and provides a new insight for the design of heterojunctions for materials with lattice mismatches. 相似文献
90.
Multifunctional Lanthanide‐Based Metal–Organic Frameworks with a Polyheterotopic Ligand: Doped with Ytterbium(III) for Luminescence Enhancement and Selective Dye Adsorption 下载免费PDF全文
《化学:亚洲杂志》2018,13(16):2126-2134
The chemistry of metal–organic frameworks has been progressing fast with its exciting potential in multifunctional applications. A series of three‐dimensional lanthanide‐based metal–organic frameworks, {[Ln(HTPO)(NO3)(H2O)]⋅x(CH3CN)⋅y(H2O)}n (Ln=Eu ( 1 ), Tb ( 2 ), Gd ( 3 ), Sm ( 4 ), Dy ( 5 ), Nd ( 6 )), {[Eu(TPO)(HCOO)0.5]⋅(H3O)0.5}n ( 7 ), {[Eu(TPO)(DMF)]⋅(solv)x}n ( 8 ; DMF= N,N‐dimethylformamide), and {[Eu(TPO)(DMA)]⋅(solv)x}n ( 9 ; DMA=dimethylacetamide) were synthesized with semirigid C3‐symmetric ligand tris(4‐carboxylphenyl)phosphine oxide (H3TPO). In these frameworks, the H3TPO ligand exists in a totally different configuration. Framework 1 exhibits good breathing properties for absorbing more guest molecules through a solvent‐induced single‐crystal‐to‐single‐crystal (SC–SC) transformation involving a configuration transformation of the organic linker in the framework. The ytterbium ion was doped into 1 to improve the luminescent performance (lifetime and quantum yield) of the red europium emission. Among a series of Eu1−xYbxTPO samples, Eu0.88Yb0.12TPO showed enhanced luminescence intensity (≈5.1 times that of the pure europium system), and the lifetime increased from 1073.08 to 1236.57 μs. Moreover, the porosity of these frameworks allows them to efficiently adsorb dye molecules with high selectivity and efficiency. 相似文献