核-壳结构磁性金属有机骨架材料Fe3O4@UiO-66-NH2的合成、表征及催化性能

UiO-66-NH_2是以Zr4+为金属,以2-氨基对苯二甲酸为配体制备得到的金属有机骨架材料,它是目前报道中具有较高热稳定性和化学稳定性的材料之一。本文以Fe_3O_4为核,以UiO-66-NH_2为壳,采用层层自组装方法制备了核-壳结构的磁性金属有机骨架材料Fe_3O_4@UiO-66-NH_2。利用X射线衍射(XRD)、傅里叶变换红外光谱(FTIR)、透射电子显微镜(TEM)、扫描电子显微镜(SEM)和氮气吸附等对其进行了表征,并考察了该磁性材料在克脑文盖尔(Knoevenagel)缩合反应中的催化性能。结果表明,该磁性材料Fe_3O_4@UiO-66-NH_2为核-壳结构,壳层厚度约为100 nm,氨基含量为1.70 mmol·g-1。该磁性复合材料具有Fe_3O_4和UiO-66-NH_2的双重功能,既可以磁性分离,又具有UiO-66-NH_2的孔结构和催化性能。由于壳层材料中Lewis酸性位(Zr4+)和碱性基团(-NH_2)的协同催化能力及其壳层的纳米尺寸效应,该磁性材料在Knoevenagel缩合反应中表现出和UiO-66-NH_2纳米粒子相当的催化活性。而且,通过磁性分离实现催化剂的多次循环使用后,其结构没有明显变化。     

有机磁性液晶化合物的研究进展

介绍了磁性液体材料和分子磁体材料的分类和发展;重点评述了近年来出现的一种集磁性和液晶性于一身的新型多功能材料--有机磁性液晶材料的产生、类型、分子结构及研究进展;对有机棒状磁性液晶分子的合成方法和应用前景进行了展望.     

金属有机骨架复合材料在样品预处理中的研究进展

金属有机骨架（MOFs）材料是近几年涌现出的一类新型多功能多孔材料,以金属离子或金属簇为配位中心,与含氧或氮的有机配体通过配位作用形成多孔骨架结构。相比于其他传统无机多孔材料,MOFs具有比表面积高、孔隙率大、热稳定性好和结构与功能多样化的特点,因而被广泛用于气体存储、催化、吸附和分离等领域。MOFs复合材料在样品预处理方面的应用引起了研究者们的极大兴趣和广泛关注。由于MOFs材料和不同功能材料如高分子聚合物、碳基材料以及磁性材料组装复合,使MOFs复合材料的性能优于原来的MOFs材料。综述了近年MOFs复合材料在样品预处理的研究应用,尤其是在固相微萃取、固相萃取以及磁性固相萃取等方面的应用。     

高性能磁性纳米粒子的有机相制备与生物应用的研究进展

磁性纳米粒子(MNPs)的合成开发在基础科学研究和技术应用方面得到了深入的发展。与大块的磁性材料不同,MNPs展现出了独特的磁性,并且可以通过系统的纳米尺寸工程调控它们的性能。本文首先简要介绍了MNPs的基本特征,总结了不同MNPs的制备方法,包括金属、合金、金属氧化物和多功能的MNPs;重点关注了可精确控制MNPs尺寸、形状、组成和结构的有机相合成方法;最后讨论了这些MNPs在生物方面的应用。     

金属有机骨架及其复合材料在固相微萃取中的制备及应用

金属有机骨架材料是近几年涌现出的一类新型多功能多孔固体材料,由金属离子和有机配体自组装形成.基于其比表面积高、孔隙率大、热稳定性好和结构与功能多样化等优点,此类材料可作为潜在的吸附剂来对水体等环境污染物进行预处理分析.此外,金属有机骨架材料和不同功能材料如碳基材料、分子印迹聚合物材料以及磁性纳米粒子等组装形成的金属有机骨架复合材料,其整体性能较优于母体金属有机骨架材料.因此,金属有机骨架复合材料在样品预处理方面的应用也引起了研究者的极大兴趣和广泛关注.结合自己的研究工作,对近5年的金属有机骨架材料以及金属有机骨架复合材料,主要在固相微萃取样品预处理方面的应用进行了综述,并对其发展前景进行了展望.     

羧基配体金属有机骨架材料作为催化剂的研究进展

<正>金属有机骨架材料(MOFs)是由无机金属中心与多齿有机配体通过配位键形成的立体网络结构多孔晶体材料[1].MOFs具有多孔性、大比表面积、结构规整、有机配体的可修饰性、金属离子的可选择性等特点,在气体吸附、气体分离、磁性材料、光学材料和催化剂等领域得到广泛的应用[2-6].尤其是在催化方面,MOFs结合了金属有机配合物和分子筛的优点,可以直接用作催化剂,也可作为催化剂载体使用.     

基于离子液体的磁性富集技术及其在分析化学中的应用进展

磁固相萃取是一种基于磁性材料而发展起来的新型样品前处理技术,是目前样品预处理领域的研究热点,其中有关磁性吸附材料的研究是该技术的关键。离子液体是一种由有机阳离子和有机或无机阴离子构成的液态有机盐类,因挥发性低,化学及热稳定性好以及对有机物、无机物具有良好的溶解性而成为富集水溶液中有机污染物和重金属离子的新型吸附材料,但将其用于磁固相萃取的研究尚处于起步阶段。本文总结了磁性富集技术中所用的离子液体,并将目前基于离子液体的磁性富集技术归纳为基于离子液体功能化磁性微球的磁固相萃取、混合半胶束磁固相萃取、离子液体参与的双磁微萃取3类。并综述了基于离子液体的磁性富集技术在环境、食品及生物样品前处理方面的应用研究,简要总结了根据待测物质选择基于离子液体的磁性富集技术的原则,并对基于离子液体的磁性富集技术未来的发展方向进行了展望。     

磁性介孔材料的研究进展

磁性介孔材料兼具介孔材料和磁性材料的双重优势,如高比表面积、孔径均一、高吸附性和可磁分离性,具有广泛的应用前景和重大的研究意义,受到化学和材料工作者的极大关注。本文综述了磁性介孔材料的制备方法及其改性研究,同时介绍了磁性介孔材料在污水处理、催化反应、药物控释和生物分子的分离提纯等领域的一些应用进展。     

热液法制备磁性纳米材料

磁性纳米材料作为新兴的无机功能材料,因其具有与常规材料不同的特殊性质,如高比表面积、强磁响应性、良好的化学稳定性和生物相容性等,被广泛应用在生物合成、生物分离、生物传感器、免疫测定、有机催化、药物传输、数据存储和环境治理等方面。目前合成磁性纳米材料的方法主要有化学共沉降法、高温热分解法、溶胶-凝胶法及热液法等。由于热液法具有条件简易、成本低廉、反应活性高、产率可观和绿色环保等优势,近年来受到了广泛的关注,并已应用在工业生产中。本文根据磁性材料组成与构成方式的不同,综述了热液法合成磁性纳米材料的研究进展。     

核-壳结构磁性金属有机骨架材料Fe3O4@UiO-66-NH2的合成、表征及催化性能

UiO-66-NH₂是以Zr⁴⁺为金属,以2-氨基对苯二甲酸为配体制备得到的金属有机骨架材料,它是目前报道中具有较高热稳定性和化学稳定性的材料之一。本文以Fe₃O₄为核,以UiO-66-NH₂为壳,采用层层自组装方法制备了核-壳结构的磁性金属有机骨架材料Fe₃O₄@UiO-66-NH₂。利用X射线衍射(XRD)、傅里叶变换红外光谱(FTIR)、透射电子显微镜(TEM)、扫描电子显微镜(SEM)和氮气吸附等对其进行了表征,并考察了该磁性材料在克脑文盖尔(Knoevenagel)缩合反应中的催化性能。结果表明,该磁性材料Fe₃O₄@UiO-66-NH₂为核-壳结构,壳层厚度约为100 nm,氨基含量为1.70 mmol·g^-1。该磁性复合材料具有Fe₃O₄和UiO-66-NH₂的双重功能,既可以磁性分离,又具有UiO-66-NH₂的孔结构和催化性能。由于壳层材料中Lewis酸性位(Zr⁴⁺)和碱性基团(-NH₂)的协同催化能力及其壳层的纳米尺寸,该磁性材料在Knoevenagel缩合反应中表现出和UiO-66-NH₂纳米粒子相当的催化活性。而且,通过磁性分离实现催化剂的多次循环使用后,其结构没有明显变化。     

芳杂环聚西佛碱Fe~(2+)配合物的合成及磁性能

以 2 ,2′ 二氨基 4 ,4′ 联噻唑 (DABT) ,2 ,6 二乙酰基吡啶 (DAP)及苯二甲醛为原料合成了三个新型结构的芳杂环聚西佛碱 (PBTAP ,PBTMP ,PBTPP) ,并制备了其相应的Fe2 + 配合物 .利用FTIR确定了聚合物及其配合物的结构 ,借助多功能材料物理特性测量系统 (PPMS :PhysicalPropertyMeasurementSystem)测定配合物的磁性能 ,测试结果表明这三个聚合物的Fe2 + 配合物都是有机软磁体 ,具有相对较高的磁饱和强度 (Ms) ,其中PBTAP Fe2 + 的磁饱和强度为 6 2emu g ,顺磁居里温度 (Tp)达 88K ,且具有S型的磁滞回线 ,此结果表明此配合物在低温下是有机软铁磁体 .     

基于扫描探针显微镜（SPM）的高密度信息存储

随着信息技术的飞速发展,高密度信息存储的研究成为国际上备受关注的研究领域。扫描探针显微技术（SPM）通过改变材料的光、电、磁等局域特性可以实现纳米尺度的信息存储,成为提高信息存储密度的最有效手段之一。本文从信息存储材料和技术角度综述了基于SPM的高密度信息存储最近的研究进展,并讨论了其将来的研究和发展方向。     

Study of Graphdiyne-based Magnetic Materials

Carbon-based magnetic semiconductors are easy to be modified with low cost and low power consumption.While they can demonstrate robust long-range magnetic ordering and show great potential for application after introducing magnetic moments.Graphdiyne(GDY),as an allotrope of carbon,exhibits intrinsic semiconductor properties and paramagnetic properties due to its unique structure and the presence of sp carbon.To improve the magnetic properties of GDY and prepare excellent magnetic semiconductor materials,scientists have done a lot of related research work.The most direct and effective method to introduce magnetism is heteroatom doping.In this review,we have entirely described the latest GDY magnetism introduction methods,effects,and theoretical calculations,etc.Doping methods include post-doping and molecular design doping.The doping elements have covered non-metallic elements(N,H,F,Cl,S),metallic elements(Fe),and functional groups.The magnetic properties of the modified GDY materials were studied by experimental analysis and theoretical calculations.This review provides a sufficient basis and direction for related researches.     

Preparation and characterization of 3D collagen materials with magnetic properties

In this study 3D collagen materials with magnetic properties were prepared by lyophilization technique. Magnetic particles were synthesized by precipitation of iron (II) sulfate heptahydrate and iron (III) chloride hexahydrate in an aqueous solution of chitosan and then added to a collagen solution. Starch dialdehyde (DAS) was used as a cross-linking agent for the materials. The properties of the obtained materials were studied using infrared spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Additionally, mechanical properties, porosity, density, swelling and moisture content were measured.It was found that 3D composites made from collagen with magnetic particles are hydrophilic with a high swelling ability. Cross-linking of such collagen materials with dialdehyde starch (DAS) alters the swelling degree, porosity and density of materials. The addition of magnetic particles to collagen materials decreases its porosity, and increases the density of the studied materials. Collagen 3D materials with magnetic particles are rigid and inflexible. Magnetic properties of the 3D collagen materials containing magnetic particles were confirmed by the interaction of this material with a magnet.     

基于有机硼酸的共价键有机框架研究进展

共价键有机框架(Covalent Organic Frameworks,COFs)是具有明确孔径分布的多孔晶体材料,在气体贮藏、催化、分离、光学器件和化学传感等方面均有应用前景。有机硼酸中硼原子最外层空的p轨道能与π键产生特殊的轨道作用,也可与路易斯碱发生配位作用。上述特点使其能够作为结构和功能导向的基元而用于构筑共价键有机框架。本文从合成、结构以及性质等方面对有机硼酸构筑的共价键有机框架进行了介绍。     

Organic Supercapacitors as the Next Generation Energy Storage Device: Emergence,Opportunity, and Challenges

Harnessing new materials for developing high-energy storage devices set off research in the field of organic supercapacitors. Various attractive properties like high energy density, lower device weight, excellent cycling stability, and impressive pseudocapacitive nature make organic supercapacitors suitable candidates for high-end storage device applications. This review highlights the overall progress and future of organic supercapacitors. Sustainable energy production and storage depend on low cost, large supercapacitor packs with high energy density. Organic supercapacitors with high pseudocapacitance, lightweight form factor, and higher device potential are alternatives to other energy storage devices. There are many recent ongoing research works that focus on organic electrolytes along with the material aspect of organic supercapacitors. This review summarizes the current research status and the chemistry behind the storage mechanism in organic supercapacitors to overcome the challenges and achieve superior performance for future opportunities.     

Spintronics and spintronics materials

The review concerns the fundamentals of spintronics (spin-transport electronics). The material covers spin-spin interactions and spin relaxation in semiconductors as well as spin and spin injection related effects in the condensed matter. Examples of promising spintronic devices are given, requirements for spintronic materials are formulated, methods of synthesis of spintronic materials are described, and the physicochemical properties of some materials are characterized. Organic spintronic materials are briefly outlined and the state-of-the art in the field of research on inhomogeneous magnetic semiconducting materials possessing high-temperature ferromagnetism is described. The emphasis is placed on the chemical bonding and electronic structure of magnetic impurities in semiconductors, consideration of the nature of ferromagnetism, and on the character of exchange interactions between localized spins in novel spintronic materials.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2255–2303, November, 2004.     

发泡PVC混合材料吸声性能的研究

发炮塑料是一种常用的吸声降噪材料，发泡ＰＶＣ－无机物混合物吸声材料是一种性能优良的新型吸声材料，它的吸声性能尤其是中低频吸声性能明显比聚氨酯、聚苯乙烯等发泡聚合物好。重点讨论了材料厚度、容重、无机物含量，无机物粒度、加热时间对材料吸声性能的影响。     

Progress of Indeno-type Organic Diradicaloids

Organic diradicaloids have unusual open-shell nature and properties and are promising materials for organic electronics, spintronics, energy storage and nonlinear optics. In this review, we focus on indeno-type organic diradicaloids and summarize their molecular design and synthesis, as well as topological structures, open-shell characters and diradical properties. The molecular systems are classified into indenofluorenes and diindenoacenes, indeno-based molecules with one-dimensional, two-dimensional and unique topological structures, and heterocyclic indeno-based molecules. By constructing these various topological π-skeletons with tunable conjugation modes and variation of atomic composition, their key open-shell parameters, such as diradical characters and singlet-triplet energy gaps, along with the optical, electronic and magnetic properties, as well as stabilities are efficiently modulated. More attention may be paid to accurate computational analysis, rational design and synthesis, and novel functions of indeno-type diradicaloids, which will promote the development of radical chemistry and materials.     

Review: Downsizing effect on 2-D and 3-D spin crossover metal-organic frameworks

This review is focused on the downsizing effect of a family of Hofmann-type Metal Organic Frameworks (MOFs) exhibiting Spin-Crossover Phenomenon (SCO) at high temperatures. Their nanoscale importance is currently under investigation concerning their multifunctional activity combining different properties such as magnetic, electrical, optical, or mechanical. General strategies for the fabrication of these materials in nanoscale will be presented as well as the development and optimization of thin film growth and nanopatterning methods. An analytical study of 2-D and 3-D tetracyanometallates SCO MOFs prepared both in their bulk form as well as nanoparticles will be outlined and the correlation of their magnetic properties with both their structures and sizes will be discussed.