溶胶-凝胶材料的制备及其应用

综述了溶胶凝胶技术的应用现状及发展趋势,着重阐述了溶胶-凝胶态物质的制备工艺及该技术在纳米粉体材料、薄膜及涂层材料、纤维材料、有机-无机复合材料等领域的应用。新型溶胶-凝胶反应机理以及溶胶向凝胶转化过程中体系微结构变化规律的研究将是今后该领域发展的主要方向。     

溶胶-凝胶法制备纳米材料研究进展

溶胶凝胶技术具有其它传统的无机材料制备方法无可比拟的优点,以溶胶凝胶技术制备的产品均匀度好、纯度高、种类多及操作温度低,溶胶-凝胶技术已成为固体材料制备的主要方法。文章阐述了溶胶-凝胶法制备纳米粒子、纳米杂化材料与纳米薄膜的方法,并对溶胶凝胶法的基本原理、过程,以及对控制团聚和粒子的形状、大小的影响因素进行了综述。     

溶胶-凝胶材料的制备及其应用

综述了溶胶凝胶技术的应用现状及发展趋势,着重阐述了溶胶-凝胶态物质的制备工艺及该技术在纳米粉体材料、薄膜及涂层材料、纤维材料、有机-无机复合材料等领域的应用。新型溶胶-凝胶反应机理以及溶胶向凝胶转化过程中体系微结构变化规律的研究将是今后该领域发展的主要方向。     

溶胶-凝胶法的应用研究

为研究溶胶-凝胶法的应用,文章通过研究溶胶-凝胶法的基本原理、工艺过程的影响因素,总结溶胶-凝胶法的优缺点。结果表明,水的加入量、温度、醇盐的滴加速度、反应液的pH都会影响溶胶-凝胶法的产品质量。溶胶-凝胶法可制得的材料主要有以下几大类型:单晶、纤维材料、涂层和薄膜材料、超细粉末材料及复合材料等,有很大的发展前景。     

溶胶-凝胶法制备超级电容器纳米电极材料的研究进展

溶胶-凝胶法是一种常用的制备超级电容器纳米电极材料的方法。利用溶胶-凝胶法制备超级电容器纳米电极材料将为获得具有优异电化学性能的材料提供了重要的方法和基础。本文介绍了电容器的制备方法及优缺点,通过分析溶胶-凝胶法制备超级电容器纳米电极材料的工艺参数、影响因素与优化策略,通过探讨溶胶-凝胶法的发展历程和相关研究成果,希望可以为今后超级电容器纳米电极材料的研究提供参考。     

溶胶—凝胶技术的研究与应用

综述了溶胶-凝胶技术在现代材料制备工艺中的应用及发展。通过对溶胶-凝胶技术的机理、特点的分析进而指出溶胶-凝胶技术中实际存在的一些问题，并为改进工艺提出了一些建议。     

溶胶-凝胶包埋固定化酶的研究

介绍了溶胶-凝胶(sol-gel)包埋法制备固定化酶的基本过程和影响因素,着重论述了S iO2、有机改性硅胶和有机/无机杂化硅胶三类溶胶-凝胶基质材料制备固定化酶的特性和在催化反应中的应用,对溶胶-凝胶包埋法制备高性能固定化酶的发展前景予以展望。     

溶胶-凝胶法的基本原理、发展及应用现状

溶胶-凝胶法是一种条件温和的材料制备方法,简述了Sol-Gel法的基本原理和主要步骤,讨论了溶胶-凝胶法在复合材料制备过程中的应用及其发展前景。     

溶胶—凝胶法在陶瓷／玻璃纤维制备中的应用

溶胶-凝胶工艺是一种很有发展前途的材料制备方法,在制备功能陶瓷材料方面已经显示出其优越性。近二、三十年来,溶胶-凝胶工艺在制备陶瓷方面也取得了重大进展,许多高性能溶胶-凝毅然法陶瓷纤维得到了广泛应用。本文简要综述了溶胶-凝胶工艺特点及其在陶瓷纤维制造方面的应用情况。     

包埋生物分子的SiO2载体材料的研究进展

综述了用于包埋生物分子生物传感器的溶胶-凝胶的制备过程,影响包埋的生物分子活性的因素、生物分子在载体中的性质以及载体的改性.重点阐述了对载体的改进,主要是对无机二氧化硅载体材料的有机掺杂.展望了新的生物兼容的溶胶-凝胶载体的设计.     

Influence of preparation method and alumina content on crystallization and morphology of porous yttria stabilized zirconia

Influence of addition of alumina and preparation methods (sol-gel synthesis and mechanochemical preparation) on crystallization and morphology of yttria stabilised zirconia was examined. Presence of alumina was found to delay crystallization of zirconia, the effect being more pronounced at higher alumina content. The two oxides form easily distinguished separate phases. Milling lowers the crystallization temperatures of the sol-gel derived powders since nuclei are formed during the milling and smaller particle size allows easier removal of residual organic components. The milling results in crystallization of some monoclinic zirconia, both in sol-gel derived powders and in case of mechanochemical processing. There are no significant differences between the preparation methods in pore size and relative density of sintered tablets: powders obtained by mechanochemical processing and milled sol-gel derived powders both give tablets with homogeneous morphology. The advantage of sol-gel process is preparation of pure tetragonal zirconia phase without traces of monoclinic phase.     

制备方法对尖晶石Li4Ti5O12负极材料的性质影响

采用高温固相法、热聚合法和改良溶胶-凝胶法制备锂离子电池负极材料Li4Ti5O12。通过X-射线衍射、扫描电镜、恒电流充放电及电化学阻抗等技术和手段表征合成产物的结构、形貌及电化学性能。结果表明：溶胶-凝胶法合成的粉末为纯相Li4Ti5O12,而高温固相法和聚合法合成的Li4Ti5O12则存在TiO2杂相。高温固相法合成的Li4Ti5O12粉末晶粒最大,溶胶-凝胶法合成的粉末晶粒最小,分布最为均匀,晶粒尺寸约为80nm。高温固相法、热聚合法和溶胶-凝胶法制备的Li4Ti5O12粉末首次放电容量分别为161.6mAh/g、165.9mAh/g和171.5mAh/g,循环25次后的容量保持率分别为84.7%、87.7%和94.3%,溶胶-凝胶法合成的Li4Ti5O12粉末电化学性能最好。     

制备方法对Co-Pd/TiO2催化剂催化CH4-CO2梯阶转化的影响

以钴、钯为活性金属, 分别采用浸渍法和溶胶-凝胶法制备了Co-Pd/TiO₂催化剂, 考察了不同制备方法制备的Co-Pd/TiO₂催化剂对CH₄-CO₂梯阶转化直接合成C₂含氧化合物的影响。利用XRD、XPS和N₂-吸附-脱附对催化剂进行了表征。结果表明:两种方法制备的催化剂反应前与反应后表面织构都存在较大变化, 且催化剂中均存在CoTiO₃物种, 这是活性金属Co与载体TiO₂之间发生强相互作用, CO²⁺替代TiO₂晶格中的Ti⁴⁺的结果;CoO和金属Pd可能是该反应的活性中心;反应前与反应后溶胶-凝胶法制备的催化剂的表面Co含量均低于浸渍法制备的催化剂, 而表面Pd含量则均高于浸渍法制备的催化剂, 且溶胶-凝胶法制备的催化剂各种产物的生成速率均高于浸渍法制备的催化剂, 因此, 与浸渍法制备的催化剂相比, 溶胶-凝胶法制备的催化剂具有更好的催化活性。     

Catalytic reduction of nitric oxide on Pt and Rh catalysts supported on alumina and titania synthesized by the sol-gel method

Platinum and rhodium supported on alumina and titania were synthesized by the sol-gel method. Characterization and catalytic activity for the reduction of nitric oxide by carbon monoxide was performed. In sol-gel ‘sintered/reduced catalysts’ a redispersion of the metal phase and higher resistance to sintering was observed. On the other hand, in the impregnated ‘sintered/reduced catalysts’, an important sintering effect was observed. The sol-gel ‘reduced catalysts’ and ‘sintered/reduced catalysts’ showed higher activity than that of impregnated reference catalysts, mainly when the titania is the support. Moreover, sol-gel preparations are more selective to N₂, whereas impregnated reference catalysts are selective to N₂O. The increase in dispersion and high resistance to sintering on sol-gel ‘sintered/reduced catalysts’ was interpreted as a surface migration effect of the metal particles buried in alumina and titania gels.     

Investigation into the influence of organic modifiers and ultradispersed hybrid fillers on the structure and properties of glass-ceramic coatings prepared by the sol-gel method

Glass-ceramic coatings on nickel and its alloys are produced from organic-inorganic hybrids by the sol-gel method. The coatings are applied using sol-gel systems composed of tetraethoxysilane (inorganic dopant), as well as of finely dispersed oxide and ultradispersed hybrid fillers. Acrylic and methacrylic acid derivatives are taken as organic modifiers. Oligocarbonate dimethacrylate-substituted tetranuclear titanium oxide clusters are used as the ultradispersed hybrid filler. The influence of the organic modifiers and ultradispersed hybrid fillers on the physicochemical processes occurring in the sol-gel systems and on the electrical parameters of the coatings are experimentally studied, and the data obtained are analyzed.     

溶胶-凝胶法制备纳米材料的研究进展

介绍了溶胶-凝胶技术的发展阶段及反应机理,溶胶-凝胶技术在合成零维、一维、二维及复合纳米材料方面的应用,对溶胶-凝胶技术今后的发展和研究方向提出了建议。引用文献45篇。     

Reinforcement of natural rubber: use of in situ generated silicas and nanofibres of sepiolite

Natural rubber composites containing silica particles generated in situ by the sol-gel process are investigated. The sol-gel processing is conducted before and after the cross-linking reaction. A good dispersion of the inorganic particles is obtained when the sol-gel reaction takes place after curing. In each case, the level of reinforcement is assessed from the mechanical and orientational behaviors. The reinforcement provided by in situ silica is compared with that obtained with anisotropic particles such as nanofibers of sepiolite.     

纳米含氟磷灰石涂层及其在模拟溶液中的行为

以Ca(NO3)2×4H2O和P2O5乙醇溶液为先驱体，六氟磷酸(HPF6)为氟引入剂，采用溶胶-凝胶法在钛合金基板上制备含氟羟基磷灰石涂层. 获得的涂层晶粒尺寸为120~150 nm. 实验结果表明，加入HPF6后形成的含氟磷灰石涂层在模拟体液中有良好的生物活性特性，在柠檬酸改性的磷酸缓冲溶液中表现出较好的稳定性.