稀土改性多金属氧酸盐的合成、表征及催化燃油深度脱硫研究

采用分步反应,分步酸化法制得硅钼钒前驱体,并通过调合原料配比制得不同钒含量的前驱体H4+xSiMo12-xVxO40·nH2O(x为1～4).以6种稀土La、Ce、Pr、Nd、Sm、Gd对制备的前驱体进行改性,制得24种稀土改性多金属氧酸盐催化剂.通过FT-IR与ICP-OES等表征手段对所制备的多金属氧酸盐催化剂进行...     

聚电解质自组装复合多层膜的研究进展

以静电机互作用为基础的聚电解质自组装复合多层膜近十年来发展非常迅速,本文总结了聚电解质自组装复合多层膜的研究历史及聚电解电解质组装的制备和表征方法,介绍了聚电解质自组装机理和自组装复合多层膜的应用,分析了两亲性聚氨酯自组装的可行性及意义。     

自组装膜的制备及其处理含铬废液的研究进展

废液中的六价铬(CrVI)严重污染环境,影响人们的身体健康。文章介绍了自组装膜几种主要的制备方法,及几种常见的处理含铬废液的方法。讨论并研究了自组装膜在处理含铬废液领域的应用。     

过渡金属取代型多金属氧酸盐催化反应研究进展

过渡金属离子与缺位多酸构成的金属取代型多酸不仅具有丰富多样的结构,而且在催化、材料、食品化学等应用领域都占有不可替代的地位.对过渡金属元素取代的经典多金属氧酸盐及其催化反应研究进展进行了概述.     

光学活性偶氮苯自组装膜的研究进展

目前,材料的研究越来越朝着精密可控的方向发展,对外场敏感材料的研究日益成为研究的热点.偶氮苯及其衍生物具有在紫外-可见光照射下发生可逆光致异构化的特性,因而偶氮苯类敏感膜材料的研究日益成为研究的热点.首先介绍偶氮苯分子光致异构现象及异构化过程中性能的变化,然后详细阐述了影响偶氮苯分子光致速率的诸多因素,最后综述了国内外...     

纳米级多金属氧酸盐的分子设计

评述了制造纳米结构的多金属氧酸盐的可行性,探索了它们的特殊性质,并对纳米级多金属氧酸盐的形成、制备及载体的选择进行了分析,展望了进一步研究和开发的前景。     

环丙沙星-磷钼多金属氧酸盐的制备及热分解动力学

报道了环丙沙星与十二磷钼酸的多金属氧酸盐化合物,用元素分析、IR、TG-DTA等方法对其进行了表征,结果显示该化合物仍保持Keggin型结构特征。同时,采用TG-DTG技术研究了标题化合物在氮气气氛中的热分解机理及非等温动力学,它的热分解过程经历了3个阶段,其中间体和残余物运用TG-DTG、IR和XRD 技术进行了确证。采用Achar方程、Coats-Redfern方程、Kissinger方程、Flynn-Wall-Ozawa方程和Starink方程对非等温动力学数据进行了分析,得到了第3步热分解反应的机理函数、动力学参数和热分解反应动力学方程,其热分解反应过程受F3（化学反应）机理控制, 表观活化能为351 kJ·mol-1,指前因子为2.57×10 30s-1。     

自组装膜在生物矿化中的应用

文章综述了自组装膜在生物矿化中的应用研究进展。介绍了有机硅烷类、有机硫化物类、脂肪羧酸类和醇胺类等自组装膜体系。概述了自组装膜在碳酸钙、草酸钙和羟基磷灰石研究中的现状,并对其今后的发展趋势进行了展望。     

树枝状分子自组装膜的组装类型和应用进展

将树枝状结构引入到分子自组装膜中来构筑功能性表面,既增加了自组装膜的稳定性,同时也为制备功能性表面提供一条有效的途径,拓宽了自组装膜的应用。对固体表面树枝状分子自组装膜的制备策略进行了综述。     

分子自组装膜的应用研究

综述分子自组装膜技术的应用研究,并就该技术在含能材料中的应用前景作了展望。     

层层自组装法修饰电极检测硫代胆碱的研究

通过层层自组装技术利用多壁碳纳米管(MWNTs)对玻碳电极进行厚度可控的表面修饰.在1.7 V电压下,分散于水中的MWNTs在玻碳电极上电沉积2 h后,分别在质量分数为1%的聚二烯丙基二甲基氯化铵溶液和1 mg/L MWNTs的四硼酸钠分散液(pH 9.18)中交替浸泡15 min,实现层层自组装修饰电极.当自组装层数为5时,得到的修饰电极对硫代胆碱(TCh)的循环伏安法检测结果与裸玻碳电极相比,氧化过电位由0.65 V降低到0.35 V,峰电流提高一倍左右,而且由于碳纳米管和双分子层结构的存在,使得电极抗产物污染能力加强,稳定性和重复性大幅度提升.该修饰电极对硫代胆碱的检测限在0.75 μm以下,在1.50～75.00 μm内呈现良好的线性关系(R=0.9998),在酶传感器的研制及农药残留的快速检测中有良好的应用前景.     

层层沉积热处理法制备超薄Cu3(BTC)2膜

基于层层沉积法,引入简单易控的热处理方式在玻璃基底表面制备出高结晶度且致密无裂缝的Cu₃(BTC)₂膜,并详细探讨热处理温度、组装时间和组装溶剂对Cu₃(BTC)₂成膜的影响。FESEM分析结果显示:膜层的厚度仅为200 nm;热处理有利于获得完整的晶体结构,且高温下膜层不会产生裂纹;组装时间为5 min或10 min,Cu₃(BTC)₂ 颗粒尺寸小且均一。然而,当组装时间延长至20 min,尺寸变得不均一,膜层表面变粗糙;通过改变组装溶剂环境,可以制备出不同维数的晶体膜。     

层层自组装技术制备类水滑石基新型薄膜材料的研究进展

类水滑石（layered double hydroxides,LDHs）具有各向异性的结构特征、特殊的理化特性及多功能性,在材料科学领域得到广泛应用。本文围绕近年来LDHs基薄膜材料的研究进展,系统概括了层层自组装技术（layer-by-layer self-assembly,LBL技术）制备的LDHs基新型薄膜材料的基础作用力（如静电吸附作用、氢键作用等）,阐述了LDHs与无机分子（如蒙脱石、二氧化锰、石墨烯等）、有机分子（如聚乙烯醇、荧光染料、聚苯乙烯磺酸盐等）等组装制备的特性薄膜材料,并总结了其在光、电、催化、生物无机材料等方面的应用。指出伴随着制备方法、化学组成及成膜作用力等方面基础研究的深入以及对LBL技术的功能化、实用化研究的日臻成熟,以LBL技术构筑的LDHs基薄膜材料必将对材料、化学、生物等科技领域产生深远的影响。     

Spinning-assist layer-by-layer assembled polysulfonamide membrane for reverse osmosis from naphthalene-1,3,6-trisulfonylchloride and piperazine

Polysulfonamide (PSA), with its chemical stability and acid-resistance, is seen as a potential material for reverse osmosis. However, the present PSA thin film composite membranes fabricated via prevailing interfacial polymerization (IP) approach generally exhibited nonfavored desalination performance. In this work, PSA membrane was assembled via spinning-assist layer-by-layer (sLbL) on a poly(vinyl alcohol) modified polyethersulfone substrate. Fabrication was carried out through sequential interfacial reaction between naphthalene-1,3,6-trisufonylchloride and piperazine by alternately dipping and drying the substrate in two monomer phases. Morphology, chemical composition, surface charge distribution as well as surface hydrophilicity were investigated as a function of repeated cycles. The sLbL assembly approach implemented facile control over membrane properties with well-organized selective layer thickness growth and twofold to threefold reduced surface roughness. As measured from spectroscopic ellipsometry, the sLbL assembled membranes exhibited a linear thickness growth at ~2.72 nm per layer. Performance test indicated that the salt rejection and water flux showed a trade-off pattern with increasing layer number. The PSA membrane with five layers showed a preferable NaCl rejection of 95.7 ± 0.4% with a water flux of 12.4 ± 0.9 L m⁻² h⁻¹ at 10 bar, whereas the IP membrane exhibited only 58% and a 22.12 L m⁻² h⁻¹ flux. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47138.     

Fabrication of photovoltaic cells using rhenium diimine complex containing polyelectrolytes by the layer-by-layer electrostatic self-assembly method

A series of poly(p-phenylenevinylene)s polycations incorporated with rhenium(I) chlorotricarbonyl bis(phenylimino)acenaphthene complex and pendant pyridinium side groups was synthesized. Due to the presence of ionic pendant groups, the polymers could be used to form multilayer thin films with sulfonated polyaniline (SPAN) by the layer-by-layer (LbL) electrostatic assembly process. The rhenium complexes could function as photosensitizers and SPAN could serve as a charge carrying polymer, and the resulting multilayer films form the active layer of photovoltaic cells. Upon irradiation of the photovoltaic devices by simulated AM 1.5 solar light, the power conversion efficiencies were measured to be of the order of 10⁻⁴%. Measurement of the incident photon-to-electron conversion efficiency (IPCE) at different wavelengths confirmed that the photosensitization was due to the presence of rhenium complexes in the polymer. The photocurrent generation and decay processes could be simulated by triexponential functions, which consisted of a rapid process followed by a relatively slow process. This paper is dedicated to Professor Ian Manners and his scientific accomplishments.     

Hydrophobization of multilayered film containing layer-by-layer assembled nanoparticle by Nafion adsorption

Summary The multilayered film on a glass substrate, assembled from cationic poly(ethyleneimine) (PEI), anionic nano-sized polystyrene (PS) latex particle and cationic PEI or poly(allylamine hydrochloride) (PAH) layer was prepared by using the layer-by-layer (LbL) technique. Hydrophobization was carried out by immersing the film in Nafion solution. The hydrophobicity with high contact angle value was achieved by adjusting deposition ionic strength and ratio of water/ethanol of Nafion solution. The existence of PS particles in the LbL film significantly enhanced hydrophobicity of the film surface.     

Photoluminescent Polymer Aerogels with R,G and B Emission

In this work, three new polymer aerogels based on 2-hydroxy ethyl methacrylate (HEMA) complexes with Eu(III), Tb(III) and La(III) are prepared and investigated. The polymer aerogels present strong photoluminescence with emissions located in the red, green and blue regions of the visible spectrum. Depending on the water content used during the preparation path, the consistency of the photoluminescent aerogels varies from rigid, regularly shaped monoliths to a flexible, fibrous material with very low density. The morpho-structural investigation was performed by FT-IR, XPS and SEM. Thermal behavior was also evaluated, while steady-state fluorescence spectroscopy, absolute PLQY and lifetime were used for the investigation of their luminescent properties. The impressive photoluminescent emission located in the red, green and blue areas of the visible spectrum is preserved irrespective of the selected porosity. Their photo-emissive properties, tunable porosity and the convenience of the preparation path could be some arguments for applications as photonic conversion mediums in special-purpose optoelectronic devices or sensors.     

预制膜层对铝合金微弧氧化陶瓷层性能的影响

在硅酸钠电解液体系中,利用微弧氧化技术,对无预制膜层和含化学氧化膜或稀土转化膜的6061铝合金表面进行陶瓷化处理,研究了预制膜层处理对陶瓷膜层性能的影响。结果表明,预制膜层处理能够降低起弧电压,有利于膜层增厚和硬度提高。无预制膜的铝合金微弧氧化膜层表面呈现凹凸不平的多孔状结构,经预制膜层处理后,其表面粗糙度变小。微弧氧化后,铝合金表面膜层主要由α-Al2O3和γ-Al2O3晶体相组成,而含预制膜层试样中,硬度较大的α-Al2O3相的相对含量较高。与无预制膜层及含化学氧化膜的试样相比,稀土转化膜试样的膜层厚度和硬度最大,粗糙度最小,表面较大较深的孔洞缺陷减少。     

Mg3(AlEU)层状氢氧化物的结构与发光性能的研究

本文采用共沉淀法合成了一系列不同Eu3+含量的Mg-Al-Eu三元层状复合金属氢氧化物(LDH).采用X-射线衍射(XRD)、红外光谱(IR)、光致发光光谱(PL)以及热重(TG-DTG)对产物进行表征,发现LDH中Eu3+/Al3+物质的量百分比小于25%时,三元LDH中Eu3+含量的增加对其结晶性没有明显的影响;当Eu3+/Al3+物质的量百分比达到25%时,其结晶质量明显变差.PL分析结果表明,所有样品中出现典型的Eu3+5DO-7FJ(J=1,2,3,4)跃迁所致的红光发射.随Eu3+含量的增加,Eu3+的发射强度明显呈增强趋势;当Eu3+/Al3+物质的量百分比达到25%时,其发射强度明显减弱.由此可知,Mg-Al-Eu LDH结构中,Eu3+/Al3+最佳物质的量百分比为20%.     

Properties of gradient polyimide aerogels prepared through layer-by-layer assembly

A series of density gradient polyimide (PI) aerogels were prepared using layer-by-layer assembly and radial freezing method. Briefly, a layer of poly(amic acid) (PAA) ammonium salt aqueous solution was first radially frozen. Then, the second layer of PAA ammonium salt (PAS) aqueous solution of different concentration was added on the top of the first PAS layer and radially frozen. A multilayer gradient PAS solid sample could therefore be fabricated by repeating this similar procedure. The density gradient PI aerogels were obtained after freezing drying and final thermal imidization treatment. Each layer of gradient PI aerogels had anisotropic pore structure, which consisted of tube-like pores along the radial direction and toward the center axis of the cylindrical samples. The compressive strength of five-layer gradient PI aerogel was higher than that of three-layer gradient and single-layer PI aerogels with the same density. The gradient PI aerogels exhibited anisotropic heat transfer behavior in the direction of density gradient, and heat transfer from the higher density side to the lower density side was faster.