组合材料学研究进展

综述了近年来组合材料学的研究进展. 首先简介了组合材料学的基本概念和历史传承, 然后重点介绍了组合材料学中的并行合成方法和高通量表征技术, 最后展示了一些用组合方法筛选新材料的成功范例. 并行合成方面包括：液滴喷射技术、阵列燃烧法、结合薄膜沉积的四元掩模技术和结合薄膜沉积的原位掩模技术等；高通量表征部分包括：针对发光表征的照相术, 扫描X射线结构/成分分析技术, 介电/铁电表征技术等. 在范例中, 给出一个发光材料, 一个磁电材料和一个电催化材料组合研究的例子. 最后, 对组合材料学的现状和未来进行了分析和展望.     

组合化学法在筛选真空紫外荧光材料中的应用

综述了近年来组合化学法在筛选新型真空紫外荧光材料研究方面取得的进展, 包括组合材料库的并行合成和高通量表征技术, 并重点介绍了组合材料库的设计艺术, 最后列举了组合化学法筛选真空紫外荧光材料体系研究的实例及结果.     

The influence of fuel additives on the behaviour of gaseous alkali-metal compounds during pulverised coal combustion

The alkali-metal vapour release during pulverised hard (bituminous) coal combustion was investigated in a semi-technical drop flow reactor in the temperature range 1100-1400 degrees C. Absolute concentrations of total gas-phase sodium and potassium species were determined using the in situ/on-line excimer laser induced fragmentation fluorescence technique (ELIF). Alkali-metal concentrations measured for the untreated coals were found to be in the range 0.1 to 4.7 ppm, depending on the temperature. As well as observing the temperature dependence, the effect of co-feeding defined amounts of silica and clay minerals was studied. In addition, to assist interpretation of ELIF measurements, ash samples were taken and analysed by scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). The additives lead to a pronounced binding of the alkali-metal species and suppression of the sharp temperature dependence observed without co-feeding. Therefore, the use of such getter materials can be confirmed as an effective way to remove corrosive alkali-metal species from the flue gas in pulverised coal combustion.     

甲烷催化燃烧中制备参数对NiO/CuO-ZrO2催化剂高温反应性能的影响

采用溶胶凝胶－超临界干燥的方法制备了NiO/CuO-ZrO2催化剂，分别考察了焙烧温度、活性组分含量对催化剂甲烷燃烧性能的影响，并利用XRD、物理吸附等手段考察了两个参数对催化剂性能影响的本质原因，发现NiO/CuO-ZrO2催化剂具有较高的催化活性，较好的高温（1 000 ℃）反应稳定性，焙烧温度对催化剂的影响很大，500 ℃是合适的焙烧温度，通过试验发现活性组分NiO为5 mol％时催化剂适于在相对较低的温度下使用，而NiO为15 mol％时，催化剂具有较好的高温稳定性。     

The use of combinatorial chemical vapor deposition in the synthesis of Ti(3-delta)O4N with 0.06 < delta < 0.25: a titanium oxynitride phase isostructural to anosovite

We employ, for the first time, a unique combinatorial chemical vapor deposition (CVD) technique to isolate a previously unreported transition-metal mixed-anion phase. The new oxynitride phase, Ti(3-delta)O4N (where 0.06 < delta < 0.25), is the first example of a complex titanium oxynitride and was synthesized within composition graduated films formed from atmospheric pressure CVD of TiCl4, NH3, and ethyl acetate. Characterization was performed by X-ray diffraction, X-ray photoelectron spectroscopy, UV-visible spectra, and SQUID magnetometry. The material crystallizes in the Cmcm space group, with the ordered nitrogen ions stabilizing the orthorhombic analogue of the monoclinic anosovite structure, beta-Ti3O5. The lattice parameters are sensitive to composition, but were determined to be a = 3.8040(1) A, b = 9.6486(6) A, and c = 9.8688(5) A for Ti(2.85(2))O4N. Powder samples were prepared through delamination of the thin films for synchrotron X-ray diffraction and magnetic measurements. It is the first example of a new phase to be synthesized using such a combinatorial CVD approach and clearly demonstrates how such techniques can provide access to new materials. This metastable phase with unusual nitrogen geometry has proved to be elusive to conventional solid-state chemistry techniques and highlights the value of the surface growth mechanism present in CVD. Furthermore, the ease and speed of the synthesis technique, combined with rapid routes to characterization, allow for large areas of phase space to be probed effectively. These results may have major implications in the search for new complex mixed-anion phases in the future.     

Combinatorial Methods for the Synthesis of Aluminophosphate Molecular Sieves

Automatic dispensing of reagents into autoclave blocks followed by synthesis, isolation, and automated structure analysis with X-ray diffractometry represents an efficient methodology for the combinatorial synthesis of microporous materials. The figure shows a typical diffractogram of as-synthesized AFI-type molecular sieves taken with a CCD camera.     

NiO/SnO2-ZrO2催化剂的制备及甲烷燃烧催化性能的研究

利用正交分析，通过溶胶凝胶－超临界干燥及复合浸渍的方法制备了NiO/SnO2-ZrO2催化剂，进行了活性评价，考察了前驱物、NiO、SnO2含量及制备方法对催化剂活性及稳定性的影响，并采用XRD、TEM对催化剂进行了表征分析，结果表明：NiO/SnO2-ZrO2催化剂具有良好的甲烷燃烧催化性能（t100%=640 ℃），其活性、稳定性与制备参数密切相关，其中NiO含量是影响催化剂活性、稳定性的最主要参数，它对催化剂稳定性和活性的影响规律正相反； SnO2组分的添加使ZrO2单斜相稳定，对催化剂起到了良好的稳定化作用，发现当SnO2含量在6 mol％左右时，催化剂具有较好的稳定性；对于制备方法，在凝胶前加入活性组分有利于催化剂的高活性，而在凝胶后加入活性组分，则有利于催化剂保持较好的稳定性；活性组分前驱物对催化剂性能影响不大，采用Ni(NO3)2作为前驱物较为合适。     

Preparation and characterization of BiFeO3 ceramic

From the technological point of view, the mutual control of electric and magnetic properties is an attractive possibility, but the number of candidate materials is limited. One of them, BiFeO₃, has critical conditions for synthesizing single phase since the temperature stability range of the phase is very narrow. Hence, various aspects of BiFeO₃ system have to be studied.

Fine particles of BiFeO₃ are obtained using a wet chemical route (combustion technique) and compared with the same product prepared by classic solid state reaction. The sintering programs have been varied in order to investigate the mechanism reactions and to show the relation between the microstructures and the magnetoelectric behavior.

The samples are characterized by using various techniques: X-ray diffraction (XRD) study is carried out for phase determination and lattice parameter calculations; scanning electron microscopy (SEM-EDX) and TEM to find out grain size and morphology; differential thermal analysis (DTA) to determine transformations of the starting materials. The obtained bulk materials were characterized (density, porosity, etc.) and correlated with the phase composition present in the samples. Electric and magnetic properties were evaluated.

This study underlines the role of the preparation route on the structural and morphological characteristic of the obtained materials and their influence on the magnetoelectric behavior.     

单一微孔模板剂一锅法制备多级结构ZSM-5沸石

以微孔模板剂四丙基氢氧化铵为单一模板剂,采用一种温和的低温水热一锅法工艺,成功制备出多级结构ZSM-5沸石(HSZs)。与传统的双模板法和后处理法相比,这种结合了沸石生长与后刻蚀于一体的新方法,不仅减少了模板剂的用量及二次酸/碱刻蚀、煅烧造成的环境污染,同时也极大地简化了合成工艺。利用XRD, N2吸附, SEM, TEM, XRF,27Al NMR与NH3-TPD等测试手段对合成的HSZs进行了全面表征,并提出了一种“成核/生长-刻蚀/再晶化”的形成机理。与传统ZSM-5沸石相比,这种具有均一梭型形貌的HSZs具有高的水热稳定性,并在三异丙苯催化裂解的探针反应中表现出优异催化性能和较长使用寿命。     

Solid phase library synthesis of cyclic depsipeptides: aurilide and aurilide analogues

A solid-phase combinatorial synthesis approach toward the cyclic depsipeptide aurilide (1) and related analogues is described. The peptide moiety 2 was assembled on trityl linker-functionalized SynPhase Crowns using an Fmoc strategy. Optimization of the tetrapeptide assembly 5 was carried out using parallel multiple synthesis and LC/MS analysis. The aliphatic moiety 3a was coupled with the solid-supported 2 using DIC/HOBt. Following deprotection and cleavage of linear precursor 26, macrocyclization was achieved under high dilution conditions. Removal of the methylthiomethyl protecting group provided aurilide (1) in 11% overall yield. Synthesis of a combinatorial library of aurilide derivatives 4 was accomplished with a similar protocol using the TranSort technique.     

Preparation,characterization and use of new lignocellulose-based bio nanocomposite as a heterogeneous catalyst for sustainable synthesis of pyrimido benzazoles

A sustainable combinatorial synthesis of densely substituted pyrimido [1,2-b] benzazole derivatives in water under microwave irradiation was performed using a new lignocellulose-based bio nanocomposite (BNC) as heterogeneous catalyst. The lignocellulosic waste peanut shells (LCWPS) were turned into a value-added product, a new BNC PS/ZnO, which was prepared via in situ hydrothermal synthesis. The as-prepared BNC was characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy and X-ray diffraction spectrum. PS/ZnO has been successfully used in a sustainable catalytic method for the synthesis of pyrimido [1, 2-b] benzazole derivatives in water under microwave irradiation. The time of this reaction was significantly reduced. This catalytic system has a very high turnover number (TON?～?10³) and turnover frequency (TOF?～?10^5?h^?1). This paper presents the benefit of sustainable management of LCWPS, a bio-sourced polymeric carbohydrate for production of new nanocatalyst.     

铽含量对硫氧化钇纳米发光材料荧光性能的影响

用燃烧法制备了不同Tb3+掺杂量的Y2O2S:Tb3+纳米发光材料,同时用高温固相法制备了不同Tb3+掺杂量的Y2O2S:Tb3+体相材料,X射线晶体衍射结果表明,制备的纳米材料和体相材料均为单一的Y2O2S相.由Debye-Scherre公式估算得到纳米颗粒的平均粒径大约为10 nm.讨论了纳米材料和体相材料Y2O2S:Tb3+中Tb3+的掺杂浓度对荧光性能的影响.激发光谱表明纳米材料的基质吸收带与体相材料相比向高能端移动了6nm,应用久保理论对此进行了定性的解释.     

Thermal study of organic electrolytes with fully charged cathodic materials of lithium-ion batteries

We systematically investigated thermal effects of organic electrolytes/organic solvents with fully charged cathodic materials (Li_0.5CoO₂) of Li-ion battery under rupture conditions by using oxygen bomb calorimeter. In the six studied systems, both the amount of combustion heat and heat release rates showed a pronounced increase with the increase in mass ratios of cathodic materials to electrolytes/solvents. More importantly, synergistic effects not simply physical mixtures have firstly been observed between cathodic materials and electrolytes/solvents in the complete combustion reactions. The results have been further analyzed by X-ray diffraction spectra, which revealed that Co₃O₄, CoO, and LiCoO₂ were the main solid products for the combustion reactions of studied systems. And there are more CoO and less LiCoO₂ products for the higher ratio of cathodic materials system and more amount of heat generated. It means that the combustion reaction, which produced CoO, generated more amount of heat than LiCoO₂. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Combustion synthesis as a novel method for production of 1-D SiC nanostructures

1-D nanostructures of cubic phase silicon carbide (beta-SiC) were efficiently produced by combustion synthesis of mixtures containing Si-containing compounds and halocarbons in a calorimetric bomb. The influence of the operating parameters on 1-D SiC formation yield was studied. The heat release, the heating rate, and the chamber pressure increase were monitored during the process. The composition and structural features of the products were characterized by elemental analysis, X-ray diffraction, differential thermal analysis/ thermogravimetric technique, Raman spectroscopy, scanning and transmission electron microscopy, and energy-dispersive X-ray spectrometry. This self-induced growth process can produce SiC nanofibers and nanotubes ca. 20-100 nm in diameter with the aspect ratio higher than 1000. Bulk scale Raman studies showed the product to be comprised of mostly cubic polytype of SiC and that finite size effects are present. We believe that the nucleation mechanism involving radical gaseous species is responsible for 1-D nanostructures growth. The present study has enlarged the family of nanofibers and nanotubes available and offers a possible, new general route to 1-D crystalline materials.     

微波辅助组合合成的研究进展

微波辅助组合合成技术是近年来发展起来的一种新的制备化合物库的组合化学技术, 它不仅可以克服传统固相组合合成技术以及液相组合合成技术无法提高产物收率的不足, 而且利用该技术所制得的化合物库中对应的是高纯度的单一化合物, 采用高通量筛选技术可以快速直接地确定高活性结构, 极大地提高了新药开发的效率. 主要就近年来微波辅助组合合成技术的研究进展情况进行介绍, 内容包括固相组合合成、基于聚合物支载的催化剂的组合合成、液相组合合成、氟相组合合成以及组合平行合成等.     

Part I: NiMoO4 Nanostructures Synthesized by the Solution Combustion Method: A Parametric Study on the Influence of Synthesis Parameters on the Materials’ Physicochemical,Structural, and Morphological Properties

The impact of process conditions on the synthesis of NiMoO₄ nanostructures using a solution combustion synthesis (SCS) method, in which agar powder and Ni(NO₃)₂ were utilized as fuel and as the oxidant, respectively, was thoroughly studied. The results show that the calcination temperature had a significant implication on the specific surface area, phase composition, particle size, band gap, and crystallite size. The influence of calcination time on the resulting physicochemical/structural/morphological properties of NiMoO₄ nanostructures was found to be a major effect during the first 20 min, beyond which these properties varied to a lesser extent. The increase in the Ni/Mo atomic ratio in the oxide impacted the combustion dynamics of the system, which led to the formation of higher surface area materials, with the prevalence of the β-phase in Ni-rich samples. Likewise, the change in the pH of the precursor solution showed that the combustion reaction is more intense in the high-pH region, entailing major implications on the physicochemical properties and phase composition of the samples. The change in the fuel content showed that the presence of agar is important, as it endows the sample with a fluffy, porous texture and is also vital for the preponderance of the β-phase.     

采用燃烧技术制备CuO纳米粒子:一种高效且环境友好的用于芳族醛合成芳族腈催化剂(英文)

CuO nanoparticles were synthesized using an energy-efficient and rapid solution combustion technique with malic acid employed as a fuel. The combustion-derived CuO nanoparticles were used as catalysts in a one-pot synthesis of aromatic nitriles from aromatic aldehydes and hydroxylamine hydrochloride. The catalyst was characterized by X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray analysis, transmission electron microscopy, and Brunauer-Emmett-Teller surface area analysis. The catalytic activity of the CuO nanoparticles in the synthesis of aromatic nitriles from aromatic aldehydes was evaluated. The present protocol offers the advantages of a clean reaction, simple methodology, short reaction duration (1-2 min), and high yield (85%-98%). The catalytic activity of the CuO nanoparticles was found to be higher than that of bulk CuO powder under the same conditions. The catalyst can also be recovered and reused up to four times with no significant loss of catalytic activity. The present approach is inexpensive and is a convenient technique suitable for industrial production of CuO nanoparticles and nitriles.     

One-step incorporation of Pd-Zn catalytic sites into organized mesoporous alumina for use in the oxidative steam reforming of methanol

In this paper we report the preparation of an organized mesoporous Pd-Zn/alumina system, by a new surfactant-assisted single-step sol-gel synthesis, performed in alcohol, using stearic acid as a chemical template, aluminum sec-butoxide as Al source and metal stearates both as Pd-Zn sources and as structural directing agents. The prepared materials have been characterized using a variety of techniques such as thermogravimetric analysis, atomic absorption spectroscopy, X-ray powder diffraction and N2 adsorption-desorption, and preliminarily tested in the oxidative steam reforming of methanol (OSRM) in the temperature range 100-400 degrees C.     

Ag/Co-Ce复合氧化物在O2及NOx气氛中催化燃烧碳烟的性能:Ag的作用

柴油车由于其良好的燃油经济性及强劲的动力得到了广泛应用,但同时柴油车尾气排放中颗粒物(PM)也对环境造成巨大污染,并严重威胁人类健康.与气体污染物相比,PM的处理难度更大,其组分复杂,起燃温度高,是当前柴油车排放问题的瓶颈和难点.颗粒过滤器(DPF)是一种有效消除PM的手段,它需要及时再生以保证其较高的碳烟捕集效率.与其他再生方案相比,连续催化再生系统工艺简单,能耗低,研发一种能够连续催化再生柴油车DPF的催化剂也成为当务之急.Ag是一种比较特殊的贵金属,其工业属性较强,价格也相对低廉.Ag基催化剂在环境催化领域有着广泛应用,已被应用于CO催化氧化、VOC催化去除及甲醛催化氧化等领域.目前的文献报道主要集中于研究Ag基催化剂负载于惰性载体对O2气氛下碳烟起燃性能的影响,并基于此讨论Ag的作用.本文利用柠檬酸络合法合成了高性能低温催化氧化材料体系xAg/Co0.93Ce0.07,探讨了不同Ag负载量对在两种气氛O2及O2+NO中催化性能的影响,并深入分析了引起此现象的原因.结果表明,Ag对Co-Ce复合氧化物的催化性能有显著的促进作用;Ag/Co-Ce复合氧化物在O2气氛下的起燃活性取决于Ag含量,Ag含量最高的样品0.3Ag/Co0.93Ce0.07催化性能最佳.而在NOx气氛下,Ag基催化剂的起燃性能不及在O2中的数值;0.2Ag/Co0.93Ce0.07与0.3Ag/Co0.93Ce0.07催化活性并列最优,其起燃温度可低至226oC.XRD及Raman的表征结果证实了Ag主要以单质形态存在,且其对Co-Ce复合氧化物的晶体结构未产生显著的影响,Ag的晶粒尺寸也未明显变化.H2-TPR则表明了Ag的负载未能提高催化剂的整体氧化还原能力,soot-TPR预示Ag甚至恶化了催化剂在惰性气氛下表面晶格氧及体相晶格氧的活性.NOx-TPD表征结果则证明了Ag对催化剂的NOx吸附有积极作用.此外,Ag/Co-Ce复合氧化物催化剂也具备了优异的耐久性及稳定性.本文还依据催化性能及表征结果剖析了碳烟在不同气氛下的催化氧化机理.在O2气氛下,Ag为反应的活性位,Ag与其表面的氧化物层AgOy之间存在一个自再生的反应循环.Ag吸附解离氧原子后,将其转化为AgOy,这表明此氧化物层不仅能够在低温下贡献表面晶格氧去除碳烟,促进氧分子向超氧物种转化,它在分解后也能将吸附氧解离为过氧物种及超氧物种.在NOx气氛下,催化剂表面硝酸根物种是催化剂催化性能维持稳定的重要因素;反应过程中催化材料表面硝酸盐物种的热稳定性筛查结果也进一步佐证了催化剂表面的AgNO3物种是碳烟起燃的决定性因素,其自身的氧化还原活性及Ag离子移动性均有利于降低碳烟的起燃温度.TGA结果说明了NOx气氛中的活性中间产物AgNO3的氧化还原活性劣于O2气氛下活性中间产物Ag2O,这直接导致催化剂在O2气氛下具备更好的碳烟起燃性能.本文工作有助于启发其他研究者开发高活性催化氧化催化材料.