有机-无机杂化介孔二氧化硅在环境保护中的应用

将有机基团通过后嫁接或共缩聚法引入到介孔二氧化硅的孔道表面或骨架中,根据有机基团在材料中的位置可得到表面结合型和桥键型两类功能化介孔材料.本文总结了有机-无机杂化介孔二氧化硅的分类及合成方法,重点介绍了该类材料作为吸附剂在环境保护中的应用,包括金属阳离子、含氧阴离子、有机污染物和气体的去除与回收.并展望了有机-无机杂化...     

功能模板导向的自组装合成介孔结构有机／无机复合材料

回顾了近年来硅基介孔材料有机功能化的基本方法和研究进展．基于作者的相关研究工作,着重介绍一种新型的介孔氧化硅有机功能化的方法——功能模板导向的自组装法,阐述了该方法在自组装合成新型有机／无机复合材料方面的应用．     

有机官能化MSU-x孔分子筛的界面特征

MSU- x是自 M41S系列介孔分子筛问世以来所合成的另一类新型介孔分子筛材料 ,它具有三维立体交叉排列的 " worm- like"孔道结构特征及采用中性模板剂、廉价无毒等诸多合成优点 [1～ 4],有着潜在的应用价值 .为了改善纯硅的介孔材料的表面和孔道性质 ,扩大其应用领域 ,除了在骨架引入金属离子或在其孔道中负载催化活性物质外 ,对介孔材料进行有机官能化制备无机-有机杂化材料改善其骨架和孔道性质是当前研究的热点之一 [5].正是由于活性有机基团的存在 ,使得这些材料可直接用于催化反应 ,或作为中间介质成为其它络合离子的主体 .由于有机基…     

磺酸基功能化MCM-41有机-无机杂化材料的合成与表征

 利用直接合成法和后接枝法将含有磺酸基团的硅烷偶联剂引入MCM-41介孔分子筛中, 合成了酸性介孔有机-无机杂化材料. 利用XRD和TEM等方法对其结构进行了表征. 结果表明,利用直接合成法和后接枝法合成的杂化材料仍保持规整的介孔孔道,该材料作为酸催化剂在苯甲醛与乙二醇的缩醛反应中显示了较好的催化活性.     

有机/无机复合介孔膜的合成及其生物酶吸附行为研究

以正硅酸四乙酯(TEOS)为硅源、三嵌段共聚物(F127)为表面活性剂, 聚碳酸酯膜为硬模板, 并采用抽滤法在聚碳酸酯膜内的亚微米级孔道中组装介孔氧化硅从而制备出有机(聚碳酸酯)/无机(介孔氧化硅)复合介孔膜. 通过扫描电镜、能量分散光谱以及透射电镜等实验表征了该有机/无机复合介孔膜的组成、结构及形貌. 研究结果表明: 通过该方法可以在聚碳酸酯膜内孔道中形成长度为9 μm、直径为200 nm的一维氧化硅棒状材料, 且该棒状材料具有无序蠕虫状和有序体心立方的混合介孔结构, 有序体心立方介孔的平均孔径约为8.5 nm. 另外, 初步考察了该复合介孔膜对生物酶的物理吸附行为, 结果表明其对肌红蛋白酶的单位吸附负载量为5.85 mg/g.     

硅基分子筛及其在精细化学品合成中的应用*

本文综述了沸石分子筛及中孔硅基材料在合成方面的最新进展,总结了这类分子筛材料在精细化学品合成中的应用及取得的成果,详细介绍了中孔分子筛的表面改性尤其是有机－无机杂化分子筛的合成、性质、特点及其作为催化剂在有机合成反应中的应用。     

"面包圈"状高有序度大孔径介孔分子筛SBA-15的合成

介孔材料因其高度有序的大孔径、较佳的催化吸附性能、良好的电磁性质及易于剪裁而引起人们极大的兴趣[1～9].人们已相继合成了介孔氧化硅薄膜[3,10]、球[12]、空心球[4,13]和纤维[12～15]等,并设法控制中孔材料晶体外貌[3～9,15～21].最近,我们报道了利用多相组装和无机晶体(如NaCl,LiCl)作大孔结构导向剂的方法[16],合成了人造"珊瑚"状介-大孔氧化硅膜[13].Lin等[17]用共表面活性剂法在丁醇存在下合成了多组有序结构的介孔氧化硅空心球; Shio等[21]在完全溶解的硅酸钠和阳离子表面活性剂溶液中,合成了细棒状介孔氧化硅粉末.本文报道一种控制介孔材料颗粒外貌和形状的新方法,即共溶剂法,并以此法合成了高有序度、大孔径、 "面包圈"状介孔氧化硅SBA-15.这种新材料有望在微加工、催化、生物分离、电子器件的矿化、色谱载体等方面得到应用[1～9].     

萘基桥联有机-无机杂化介孔材料的合成及其光学性质

以短链阳离子三聚表面活性剂C₁₀H₂₁N⁺(CH₃)₂(CH₂)₂N⁺(CH₃)(C₁₀H₂₁)(CH₂)₂N⁺(CH₃)₂C₁₀H₂₁]·3Br^?为结构导向剂, 通过2,7-二(3-三乙氧硅基氨丙酯基)萘(NIS)和四乙氧基硅烷(TEOS)共缩聚, 制备了有序的萘基桥联的杂化周期性介孔有机硅(PMOs). 样品通过X射线衍射(XRD)、高分辨透射电镜(HRTEM)、氮气吸附-脱附、差示扫描量热/热重分析(DSC/TGA)表征. 结果表明, 当NIS占NIS和TEOS总量40% (摩尔分数)时, 可以形成具有结晶态孔壁的有序介孔杂化材料. 当NIS含量低于或高于40%时, 分别形成无定形孔壁的有序介孔杂化材料和无孔杂化材料. 随着孔壁中萘基基团的增加, 由于有机基团之间π-π堆积作用增强, 杂化介孔材料显示良好的热稳定性. 由于在二氧化硅骨架中嵌入荧光萘基基团, 杂化有机-无机有序介孔材料显示了激基缔合物的光学行为. 随萘基基团含量的增加, 杂化材料的紫外吸收峰发生蓝移, 形成H聚集体; 由于聚集引起的荧光淬灭, 杂化材料的荧光量子产率明显降低.     

一种新型有机-无机杂化介孔碱性催化材料的合成与表征

通过直接合成方法, 制备了胺基功能化的HMS型有机无机杂化介孔碱性催化材料(Amx-HMS).采用粉末X射线衍射分析、透射电镜、氮气吸附-脱附、29Si固体核磁共振、 红外光谱和元素分析等方法对合成材料进行了表征. 通过典型的2'-羟基苯基甲基酮和苯甲醛缩合制备黄烷酮的反应对其碱催化活性中心进行了表征.     

有序介孔硅胶及其复合材料作固定相在液相色谱中的应用

系统地介绍了有序介孔硅胶及其复合材料的研究进展。重点评述了颗粒状无机介孔硅胶材料、颗粒状有机-无机复合介孔硅胶材料、手性介孔硅胶材料和整块介孔硅胶材料在用作液相色谱固定相方面的最新进展。对硅基有序介孔材料制备方面存在的问题进行了分析,并就该领域今后的发展趋势做了展望。     

Organic-inorganic hybrid mesoporous silicas: functionalization, pore size, and morphology control

Topological design of mesoporous silica materials, pore architecture, pore size, and morphology are currently major issues in areas such as catalytic conversion of bulky molecules, adsorption, host-guest chemistry, etc. In this sense, we discuss the pore size-controlled mesostructure, framework functionalization, and morphology control of organic-inorganic hybrid mesoporous silicas by which we can improve the applicability of mesoporous materials. First, we explain that the sizes of hexagonal- and cubic-type pores in organic-inorganic hybrid mesoporous silicas are well controlled from 24.3 to 98.0 A by the direct micelle-control method using an organosilica precursor and surfactants with different alkyl chain lengths or triblock copolymers as templates and swelling agents incorporated in the formed micelles. Second, we describe that organic-inorganic hybrid mesoporous materials with various functional groups form various external morphologies such as rod, cauliflower, film, rope, spheroid, monolith, and fiber shapes. Third, we discuss that transition metals (Ti and Ru) and rare-earth ions (Eu(3+) and Tb(3+)) are used to modify organic-inorganic hybrid mesoporous silica materials. Such hybrid mesoporous silica materials are expected to be applied as excellent catalysts for organic reactions, photocatalysis, optical devices, etc.     

A General Method for Preparing Bridged Organosilanes with Pendant Functional Groups and Functional Mesoporous Organosilicas

New organosilica precursors containing two triethoxysilyl groups suitable for the organosilica material formation through the sol‐gel process were designed and synthesised. These precursors display alkyne or azide groups for attaching targeted functional groups by copper‐catalysed azide–alkyne cycloaddition (CuAAC) and can be used for the preparation of functional organosilicas following two strategies: 1) the functional group is first appended by CuAAC under anhydrous conditions, then the functional material is prepared by the sol‐gel process; 2) the precursor is first subjected to the sol‐gel process, producing porous, clickable bridged silsesquioxanes or periodic mesoporous organosilicas (PMOs), then the desired functional groups are attached by means of CuAAC. Herein, we show the feasibility of both approaches. A series of bridged bis(triethoxysilane)s with different pending organic moieties was prepared, demonstrating the compatibility of the first approach with many functional groups. In particular, we demonstrate that organic functional molecules bearing only one derivatisation site can be used to produce bridged organosilanes and bridged silsesquioxanes. In the second approach, clickable PMOs and porous bridged silsesquioxanes were prepared from the alkyne‐ or azide‐containing precursors, and thereafter, functionalised with complementary model azide‐ or alkyne‐containing molecules. These results confirmed the potential of this approach as a general methodology for preparing functional organosilicas with high loadings of functional groups. Both approaches give rise to a wide range of new functional organosilica materials.     

有机修饰的含钴HMS对环己烷选择氧化反应的催化活性

以十六胺为模板剂,采用一步共聚的方法,室温下合成出了骨架含金属钴离子,表面连接疏水性有机基团的双功能化中孔氧化硅材料,并在环己烷液相氧化反应中考察了该材料的催化活性.有机基团的引入能够显著提高催化剂的活性,其中苯基效果最佳,其次是甲基和丙基.     

Medical applications of organic-inorganic hybrid materials within the field of silica-based bioceramics

Research on bioceramics has evolved from the use of inert materials for mere substitution of living tissues towards the development of third-generation bioceramics aimed at inducing bone tissue regeneration. Within this context hybrid bioceramics have remarkable features resulting from the synergistic combination of both inorganic and organic components that make them suitable for a wide range of medical applications. Certain bioceramics, such as ordered mesoporous silicas, can exhibit different kind of interaction with organic molecules to develop different functions. The weak interaction of these host matrixes with drug molecules confined in the mesoporous channels allows these hybrid systems to be used as controlled delivery devices. Moreover, mesoporous silicas can be used to fabricate three (3D)-dimensional scaffolds for bone tissue engineering. In this last case, different osteoinductive agents (peptides, hormones and growth factors) can be strongly grafted to the bioceramic matrix to act as attracting signals for bone cells to promote bone regeneration process. Finally, recent research examples of organic-inorganic hybrid bioceramics, such as stimuli-responsive drug delivery systems and nanosystems for targeting of cancer cells and gene transfection, are also tackled in this tutorial review (64 references).     

Post-treatment and characterization of novel luminescent hybrid bimodal mesoporous silicas

A novel luminescent hybrid bimodal mesoporous silicas (LHBMS) were synthesized via grafting 1,8-Naphthalic anhydride into the pore channels of bimodal mesoporous silicas (BMMs) for the first time. The resulting samples were characterized by powder X-ray diffraction (XRD), N₂ adsorption/desorption measurement, Fourier transform infrared spectroscopy (FT-IR), Transmission electron microscopy (TEM), UV-vis absorption spectroscopy, and Photoluminescence spectroscopy (PL). The results show that 1,8-Naphthalic anhydride organic groups have been successfully introduced into the mesopores of the BMMs and the hybrid silicas are of bimodal mesoporous structure with the ordered small mesopores of around 3 nm and the large mesopores of uniform intra-nanoparticle. The excellent photoluminescent performance of LHBMS has a blue shift compared to that of 2-[3-(triethoxysilyl) propyl-1 H-Benz [de]isoquinoline-1, 3(2 H)-dione, suggesting the existence of the quantum confinement effectiveness.     

Synthesis,Bifunctionalization, and Remarkable Adsorption Performance of Benzene‐Bridged Periodic Mesoporous Organosilicas Functionalized with High Loadings of Carboxylic Acids

Highly ordered benzene‐bridged periodic mesoporous organosilicas (PMOs) that were functionalized with exceptionally high loadings of carboxylic acid groups (COOH), up to 80 mol % based on silica, have been synthesized and their use as adsorbents for the adsorption of methylene blue (MB), a basic dye pollutant, and for the loading and release of doxorubicin (DOX), an anticancer drug, is demonstrated. These COOH‐functionalized benzene? silicas were synthesized by the co‐condensation of 1,4‐bis(triethoxysilyl) benzene (BTEB) and carboxyethylsilanetriol sodium salt (CES), an organosilane that contained a carboxylic acid group, in the presence of non‐ionic oligomeric surfactant Brij 76 in acidic medium. The materials thus obtained were characterized by a variety of techniques, including powder X‐ray diffraction (XRD), nitrogen‐adsorption/desorption isotherms, TEM, and ¹³C and ²⁹Si solid‐state NMR spectroscopy. Owing to the exceptionally high loadings of COOH groups, their high surface areas, and possible π? π‐stacking interactions, these adsorbents have very high adsorption capacities and extremely rapid adsorption rates for MB removal and for the controlled loading/release of DOX, thus manifesting their great potential for environmental and biomedical applications.     

Electroanalytical Applications of Microporous Zeolites and Mesoporous (Organo)Silicas: Recent Trends

Microporous zeolites and ordered mesoporous (organo)silicas have been widely used as electrode modifiers because of their attractive properties (ion exchange and size selectivity of zeolites, well ordered nanoreactors containing a high number of widely accessible active centers in mesoporous (organo)silicas). These properties have been intelligently combined to selected redox processes to improve the response of the resulting modified electrodes or to design novel electrochemical detection schemes. This up‐to‐date review provides the recent advances made in the electroanalytical applications of zeolite modified electrodes and discusses the interest of ordered mesoporous (organo)silica materials in electroanalysis.     

Mesoporous Silica Layer: Preparation and Opportunity

Periodic mesoporous silicas, which were prepared from silica‐surfactant mesostructured materials, have been investigated for a wide range of application due to their very large surface area, high porosity, pore size uniformity and variation, periodic pore arrangement and possible pore surface modification, after the pioneering papers on the formation of mesoporous silicas (MCM‐41 and FSM‐16). Morphosyntheses from such macroscopic morphologies as bulk monolith and film to nanoscopic ones, nanoparticles and their stable suspension, make mesoporous materials more attractive for applications and detailed characterization. Mesoporous silicas have been studied initially for such applications as adsorbent and catalyst, and more recently, optical, electronic, and bio‐related applications have been investigated. This review summarizes the studies on mesoporous silica film to highlight the present status and future of the preparation, characterization and application of the mesoporous silica film.