富勒醇与阳离子聚电解质复合薄膜的制备与表征

采用静电自组装技术制备了富勒醇与聚对亚苯亚乙烯基 (PPV)的前驱体、聚二烯丙基二甲基氯化铵(PDDA)的复合薄膜 ,利用紫外 可见光吸收光谱 (UV Vis)、原子力显微镜 (AFM )、透射电镜 (TEM)和X射线光电子能谱 (XPS)对薄膜进行了表征 .UV Vis吸收光谱显示 ,在特定波长下自组装薄膜的吸光度与薄膜的双层数成线性关系 ,组装过程具有一致性与重复性 .AFM图象显示富勒醇组装到基片表面后形成直径为几十到10 0多nm的团簇 .富勒醇溶液过滤后组装薄膜 ,薄膜具有较好的均匀性 ;富勒醇溶液不经过滤 ,直接组装薄膜 ,将在薄膜中引入C6 0 晶粒 .XPS分析结果提示C6 0 被羟基修饰并通过静电吸引机制与阳离子聚电解质组装成膜 .富勒醇与PPV的前驱体、PDDA具有很好的自组装性能 ,膜层间的结合力较强 ,所组装的薄膜具有较高的牢固度 .     

SnO2-TiO2薄膜载体对Au-Pt纳米颗粒电化学性能的影响

采用真空镀膜法在玻碳(GC)电极表面修饰SnO2-TiO2薄膜, 在SnO2-TiO2/GC复合电极表面组装Au-Pt双金属纳米颗粒, 制得Au-Pt/SnO2-TiO2/GC复合电极. 通过循环伏安法(CV)研究了SnO2-TiO2薄膜载体对Au-Pt双金属纳米颗粒电化学性能的影响; 采用扫描电镜(SEM)及X射线光电子能谱(XPS)对Au-Pt在SnO2-TiO2薄膜沉积的形貌及结构进行了表征. 研究结果表明, 10 nm的Au-Pt双金属纳米颗粒均匀地组装于SnO2-TiO2薄膜表面; SnO2-TiO2薄膜载体改善了复合电极抗CO中毒能力; Au-Pt双金属合金的形成提高了Pt 对甲醇氧化的电催化能力, SnO2-TiO2薄膜载体又使Pt纳米粒子d空轨道增多, 提高了Au-Pt双金属纳米颗粒的稳定性和催化性能.     

Ag/ZIF-90自组装薄膜的制备及SERS活性研究

合成了金属有机框架化合物沸石咪唑框架-90(ZIF-90)溶胶和ZIF-90晶体薄膜,分别以这2种材料为基底,制备出了Ag@ZIF-90复合材料和Ag/ZIF-90自组装薄膜.通过傅里叶变换红外(FT-IR),X射线衍射(XRD),扫描电子显微镜(SEM)对产物进行表征,分析了它们的形貌和结构特征.以罗丹明6G(R 6G)作为检测分子,对所制备材料的表面增强拉曼散射(SERS)性能进行测试.结果表明制备出的Ag/ZIF-90自组装薄膜具有好的SERS性能,而ZIF-90本身的拉曼峰并不会对Ag/ZIF-90自组装薄膜的SERS检测效果产生影响.这种材料可以作为一种较好的表面增强拉曼(SERS)活性基底,在农药残留检测方面具有很好的应用前景.     

静电自组装铁电超薄膜及其性能研究

利用静电自组装方法在石英玻璃表面交替沉积聚二烯丙基二甲基氯化铵(PDDA)和聚偏氟乙烯(PVDF)超薄膜,制得PDDA/PVDF铁电复合超薄膜.通过石英晶体微天平实时监测超薄膜的沉积,研究了超薄膜的表面形貌、结构及电性能.结果表明,自组装每层PVDF超薄膜的厚度为7.5 nm;PDDA/PVDF铁电复合超薄膜的表面平整、均匀,其中C1s的光电子能谱与极化处理后充负电荷的PVDF铁电聚合物一致,但F1s由于溶解再组装过程而降低了0.3 eV;静电自组装材料纳米级的薄膜厚度和聚合物的络合作用导致了铁电复合超薄膜的非晶结构和高的表面电阻率.     

自组装超薄膜修饰Ta2O5介质膜及其特性研究

采用静电自组装方法在五氧化二钽(Ta2O5)介质氧化膜上制备了聚二烯丙基二甲基氯化铵(PDDA)/聚苯乙烯磺酸钠(PSS)和聚二烯丙基二甲基氯化铵/聚-3,4-乙烯二氧噻吩-聚苯乙烯磺酸钠(PEDOT-PSS)超薄膜.研究了两种自组装超薄膜在Ta2O5介质氧化薄膜上的组装特性.结果表明两种自组装膜能够稳定地组装于Ta2O5介质膜表面,并有效降低薄膜的表面粗糙度.进一步研究了两种自组装超薄膜修饰的Ta2O5电容结构的电性能.结果表明静电自组装膜对Ta2O5介质膜表面进行修饰后,有效地隔离了介质氧化膜中的缺陷,降低了电容的漏电流并提高耐电压能力;研究还发现不同厚度的超薄膜对Ta2O5电容结构的耐压特性有不同程度的影响,较厚的薄膜可以更好地提高电容的耐压能力并降低漏电流,但会增加电容的等效串联电阻(ESR).另外,在相同薄膜层数的情况下,聚合物电解质PEDOT-PSS良好的导电性能降低了复合超薄膜的电阻,使得PDDA/PEDOT-PSS修饰的电容结构ESR值较低.     

金核银壳纳米粒子薄膜的制备及SERS活性研究

采用柠檬酸化学还原法制备金溶胶, 通过自组装技术在石英片表面制备金纳米粒子薄膜, 在银增强剂混合溶液中反应获得金核银壳纳米粒子薄膜. 用紫外-可见吸收光谱仪和原子力显微镜(AFM)研究了不同条件下制备的金核银壳纳米粒子薄膜的光谱特性和表面形貌, 并以结晶紫为探针分子测量了金核银壳纳米粒子薄膜的表面增强拉曼光谱(SERS). 结果表明, 金纳米粒子薄膜的分布、银增强剂反应时间的长短对金核银壳纳米粒子薄膜的形成均有重要影响. 制备过程中, 可以通过控制反应条件获得一定粒径的、具有良好表面增强拉曼散射活性的金核银壳纳米粒子薄膜.     

疏水性有序介孔氧化硅薄膜的制备

采用溶胶−凝胶技术并结合蒸发诱导自组装工艺, 以三嵌段共聚物EO₂₀PO₇₀EO₂₀ (P123)为模板剂, 使用浸渍提拉法制备了有序介孔氧化硅薄膜, 并使用不同的表面修饰剂对薄膜进行表面处理, 制备了疏水性有序介孔氧化硅薄膜. 利用FT-IR、小角XRD、HRTEM分别表征薄膜的化学物种和孔结构, 探讨了热处理温度和老化时间对薄膜介孔结构的影响, 通过接触角测试研究薄膜的疏水性能, 考察了修饰剂种类、修饰浓度和修饰时间对薄膜疏水性的影响, 结果表明所制备的薄膜为高度有序的介孔氧化硅薄膜, 孔径大小约为8 nm|表面修饰对薄膜的有序性有一定影响, 经三甲基氯硅烷(TMCS)和g-氨丙基三乙氧基硅烷(KH-550)修饰后的薄膜具有很好的疏水性能, 接触角分别为112°和96°|修饰后薄膜的水汽稳定性良好, 仍能保持有序介孔结构, 孔径达7.5 nm, 接触角达93°.     

自组装制备二氧化铪图案化薄膜

采用短波紫外光(UV)在十八烷基三氯硅烷(OTS)自组装单分子层刻蚀不同的微型图案,利用液相自组装技术在OTS模板表面沉积HfO₂图案化薄膜。通过XRD、AFM、SEM、EDS等测试手段对OTS膜和HfO₂薄膜进行表征,结果表明：以OTS为模板利用液相自组装技术成功制备出边缘轮廓清晰、粗糙度较小、条纹宽度为10μm的立方晶型的HfO₂图案化薄膜。     

类金刚石碳薄膜对碳膜导电性能的影响

以聚酰亚胺薄膜为原料,经炭化形成碳膜;进而在碳膜表面制备了类金刚石碳(DLC)薄膜,研究了制备条件对碳膜导电性能的影响.采用扫描电镜分析了薄膜的表面形貌和微观结构;采用X射线衍射仪分析了薄膜的晶体结构.结果表明,DLC薄膜的电阻率随着沉积时间的延长先减小后增加;当沉积时间达到3 h时,相应DLC薄膜的电阻率达到最小值5.66×10-5Ω.m.     

气氛氧压对PLD法生长Nd:LuVO4薄膜的性能影响

采用脉冲激光沉积技术在不同气氛和氧分压下, 在抛光石英片上生长了一系列(200)面择优取向的NdLuVO4薄膜. 利用X射线衍射(XRD)分析了所制备薄膜性能, 认为成膜较为适宜的气氛为氧气, 且氧分压为20 Pa时所得到的薄膜性能较好. 利用原子力显微镜(AFM)观察了NdLuVO4薄膜的表面形貌, 分析了氧分压的存在对薄膜表面质量的影响. 利用卢瑟福背散射(RBS)分析了薄膜的组成, 发现薄膜的成分组成与靶材的成分较为一致. 利用棱镜耦合法测得了该薄膜中每条模所对应的有效折射率为2.0044和1.7098.     

Influence of solution conditions on formation of amphiphilic hyperbranched polyanion/linear polycation multilayer films

Amphiphilic hyperbranched polyester (P2) consisting of a hydrophobic core, surrounded by aromatic carboxylic acids, is self-assembled into aggregates in aqueous solution at pH region of 3.8–4.7 and in THF–water mixed solution at THF/water volume ratio of 1/100–1/10. With P2 in both aqueous and THF–water mixed solution as polyanion and linear poly(diallydimethylammonium chloride) (PDAC) as polycation, self-assembled films were successfully formed by layer-by-layer dipping. The solution condition of P2, including the pH of aqueous solution and the THF/water volume ratio, affected not only the absorption behavior of P2 but also the surface morphology and hydrophilicity of the films with P2 as the outmost layer. At lower pH or higher THF/water volume ratio the aggregation of P2 in solution was enhanced, thus resulting in higher adsorption rate for P2, more rough and less hydrophilic surface for the films.     

Orthogonally reactive SAMs as a general platform for bifunctional silica surfaces

We report the synthesis and self-assembly of azide and amine trimethoxysilanes that result in mixed monolayers on silica. The amine and azide functional groups can be independently reacted with acid chlorides and terminal alkynes, respectively. Consequently, these orthogonally reactive monolayers represent a general starting point for making bifunctional surfaces. Using X-ray photoelectron spectroscopy, we determined the azide/amine surface ratio as well as the reactivity of the azide and amine functional groups in the mixed self-assembled monolayer (SAM). Significantly, the surface azide/amine ratio was much lower than the azide/amine ratio in the self-assembly mixture. After determining the self-assembly mixture composition that would afford 1:1 azide-amine mixed monolayers, we demonstrated their subsequent functionalization. The resulting bifunctional surface has a similar functional group ratio to the azide/amine precursor SAM demonstrating the generality of this approach.     

Sulfur-containing polymers. V. Preparation of polyoxycarbonylsulfenamides by polycondensation of bis(oxycarbonylsulfenyl chlorides) with diamines

Polyoxycarbonylsulfenamides (POSA) have been prepared by interfacial polycondensation of bis(oxycarbonylsulfenyl chlorides) with diamines. The polymers obtained ranged in physical form from crystalline solids to resinous materials depending on the kind of both bis(oxycarbonylsulfenyl chlorides) and diamines used. Some of the polymers gave transparent pliable films from chloroform solution. The polymer films decomposed with liberation of carbonyl sulfide on being subjected to ultraviolet radiation.     

旋涂-逐层自组装制备光响应性聚丙烯酸酯类偶氮聚电解质多层膜

偶氮聚电解质的静电逐层自组装是实现偶氮聚合物功能性的重要手段,是制备诸如光存储材料、光开关材料和非线性光学材料等的新途径.因此,光响应性偶氮聚电解质的静电逐层自组装已引起了人们的广泛关注.静电逐层自组装通常在水溶液中进行,即通过基材在在水溶液中的交替浸渍和逐层     

Micro- and nanopatterned copper structures using directed self-assembly on templates fabricated from phase-separated mixed Langmuir-Blodgett films

We report a versatile method to confine metal thin films in micro- and nanopatterns using directed self-assembly on the templates fabricated from phase-separated mixed Langmuir-Blodgett (LB) films. The pattern of the mixed LB films can be tuned by adjusting intermolecular interaction between the film-forming molecules in the LB films and by varying the fabrication conditions of the films such as the mixing ratio, subphase temperature, and surface pressure. We use the patterned LB films for templates to confine metal in patterned regions, taking advantage of the difference between the surface free energy of the patterned regions and that of the self-assembled monolayer of the silane coupling agent. Au nanoparticles are confined onto the patterned films as a catalyst for the succeeding Cu electroless deposition. The atomic force microscopic images, Auger electron spectra, and scanning Auger electron maps of a Cu-deposited film show that Cu is selectively deposited on the patterns of phase separation of the original mixed LB films.     

Local packing environment strongly influences the frictional properties of mixed CH3- and CF3-terminated alkanethiol SAMs on Au(111)

Compositionally mixed, self-assembled monolayers (SAMs) derived from 16,16,16-trifluorohexadecanethiol and a normal alkanethiol, either hexadecanethiol or pentadecanethiol, were formed on Au(111) substrates. The relative composition of the films was determined using X-ray photoelectron spectroscopy and was found to approximately equal the equimolar composition of the isooctane solution from which they were formed. The frictional properties of the mixed films were measured on the nanometer scale using atomic force microscopy and were observed to decrease when the chain length of the CH(3)-terminated component was shortened by one methylene unit (i.e., when hexadecanethiol was replaced by pentadecanethiol). For comparison, the frictional properties of a mixed-chain-length CH(3)-terminated SAM derived from hexadecanethiol and pentadecanethiol in a 1:1 ratio was also examined. In contrast to the mixed CF(3)/CH(3) system, the latter mixed-chain-length system exhibited relatively higher friction when compared to single-component SAMs derived solely from either hexadecanethiol or pentadecanethiol. For both types of mixed films, the change in frictional properties that occurs as a result of modifying the position of neighboring terminal groups with respect to the surface plane is discussed in terms of the influence of local packing environments on interfacial energy dissipation (friction).     

Self-assembled monolayers of ferrocene-substituted biphenyl ethynyl thiols on gold

Homogeneous and mixed [with biphenylthiol (BPT)] self-assembled monolayers (SAMs) of ferrocene-substituted biphenyl ethynyl thiols (Fc) were prepared on Au(111) substrates and characterized by several complementary spectroscopic techniques. The mixed films were fabricated either by subsequent immersion of the substrates into the BPT and Fc solutions or by immersion of the substrate into a mixed solution of BPT and Fc. The first procedure resulted in the preparation of high-quality mixed SAMs, in which the Fc molecules were stochastically distributed in the BPT matrix and well-separated from each other. The portion of these molecules in such films could be precisely varied from ca. 7 to 42% by selection of the immersion time in the BPT solution. The films prepared from the mixed solution exhibited a phase separation between the Fc and BPT constituents. These films contained mostly the Fc molecules ( approximately 80-90%), showing, thus, a significant deviation from the relative content of the target molecules in the primary solution (a 1:1 ratio). This finding shows that the Fc molecules, when competing with BPT, preferably adsorb onto Au(111) substrate, suggesting a significant impact of the ferrocene groups onto the structure-building interactions responsible for molecular self-assembly.     

铁表面自组装缓蚀功能膜的电化学阻抗谱研究

在铁表面自组装十四烷基胺膜.研究该膜在0.5 mol/LH2SO4溶液中对铁的缓蚀性能.电化学阻抗谱测试表明,随着组装时间的延长,缓蚀性能也随之增强,最大缓蚀效率为68.7%.而以十二烷基硫醇和十四烷基胺修饰的混合膜则更为致密、稳定,对铁的缓蚀能力也明显优于仅以十二烷基硫醇或十四烷基胺修饰的单一膜,其缓蚀效率可提高至78.2%.     

Self-assembled arrays of silica particles on the patterns reflecting the phase-separated structures of mixed Langmuir–Blodgett films

In this study, we constructed self-assembled arrays of silica particles on the micro- and nanopatterns of functionalized templates fabricated from phase-separated mixed Langmuir–Blodgett (LB) films. Electrostatic interaction between the carboxylic groups of silica particles and amino groups on the functionalized templates results in the formation of the self-assembled arrays of silica particles. The patterns of the silica particle arrays can be designed by controlling the phase-separated structures of the original mixed LB films.     

正、叔十二烷基硫醇在铜表面上自组装膜测试

研究了正、叔十二烷基硫醇在铜表面上的自组装及混合自组装成膜情况,并利用交流阻抗和极化曲线电化学方法测试了正、叔十二烷基硫醇在铜表面上自组装膜及混合自组装膜对铜的耐腐蚀性,考察了正十二烷基硫醇自组装膜质量与正十二烷基硫醇溶液的浓度及组装时间的关系。研究结果显示,混合自组装膜的质量及其对铜的耐腐蚀性比仅组装正或叔十二烷基硫醇均有很大的提高。