Thick silicate glass film by an interfacial polymerization

A silicate glass film of 2–20 µm in thickness has been formed on a fused quartz substrate by a sol-gel process using an interfacial polymerization technique. A partially hydrolyzed silicon alkoxide was dissolved in hexane and brought into contact with ammonia water in a cylindrical Teflon container. A silica gel film formed at the interface between the two immiscible liquids by the polycondensation of the partially hydrolyzed silicon alkoxide was gently placed on a substrate at the bottom of the container, by draining the liquid. The crack free gel film was dried in an ambient atmosphere and dip-coated with boron ethoxide, followed by sintering in an oven at 1250°C for 1 h. The glass film thus obtained was highly transparent and 2–20 µm in thickness depending on the concentration of the precursor solution and the pH of ammonia water.     

Preparation of Thick PZT Ceramic Film by an Interfacial Polymerization

The formation of a PZT film of 10–20 m in thickness via an interfacial polymerization of metal-organic precursors has been studied. A commercially available PZT precursor solution developed for dip- or spin-coating was diluted with hexane containing acetylacetone as chelating agent. The solution was poured on water contained in a teflon reaction container of 88 mm inside diameter. A translucent gel film was formed at the interface of the two immiscible liquids. While floating on water it shrank as the evaporation of solvent proceeded until its diameter decreased to about 45% of its initial value. The dried gel film was almost pore free and its thickness was estimated to be about 10 m.     

硫化镉纳米膜的生物还原-化学沉淀耦合制备及其性能表征

本文应用生物还原-化学沉淀耦合反应(CRBRCP-EDTA)制备出硫化镉纳米薄膜,并借助XRD和SEM对合成材料的物相、结构、形貌进行了表征。研究表明,以铝片为基底时CdS难以沉积,CdS纳米薄膜不能形成;以导电玻璃和单晶硅片为基底时CdS纳米薄膜方可生成。导电玻璃和单晶硅片薄膜都是双层结构,导电玻璃薄膜下层厚度大约40~50 nm,上层厚度大约450~500 nm,整体厚度大约500~550 nm;硅片薄膜的上下两层厚度基本相等,均为300 nm左右,而整体厚度达到600~650 nm。Cd²⁺浓度增加和分散剂PAM加入显著改善了导电玻璃薄膜质量,膜的致密性、均匀性和光催化活性都有所提高。     

磷酸铁纳米薄膜复合光波导氨气传感元件的制备

将硝酸铁和甲醇、磷酸溶液按一定比例混合后,通过旋涂法制备了磷酸铁（FePO₄）纳米薄膜,测定了匀胶机转速对膜厚及烘干温度对膜厚和折射率的影响,并发现薄膜的烘干温度超过150 ℃时,薄膜的厚度（130 nm）和折射率(1.7)变化不大。将该薄膜固定在钾离子交换玻璃光波导表面,研制出FePO₄膜/K⁺交换玻璃复合光波导。酸碱指示剂溴百里酚兰（BTB）作为敏感试剂,固定在复合光波导表面,研制了BTB膜-FePO₄膜/K⁺交换玻璃复合光波导氨气传感元件。采用自装的光波导气体传感检测系统对不同浓度的氨气进行了检测。结果表明,该传感元件能够检测0.35 mg/m³浓度的氨气,并具有响应（10 s）及恢复（90 s）速度快、可逆性好、连续使用等特点。     

Property of ionic liquid in electrophoresis and its application in chiral separation on microchips

The aqueous solution of a kind of room-temperature ionic liquids (RTILs), 1-ethyl-3-methylimidazolium-tetrafluoroborate (1E-3MI-TFB), demonstrated its exclusive electroosmotic property in microchip electrophoresis. It was applied as the working electrolyte for chiral separation in glass microchip electrophoresis. Compared with boric acid buffer, 1E-3MI-TFB aqueous solution exhibited a broader separation window for enantiomers of dipeptides. Then the influences of chiral selector, pH and concentration on efficiency of chiral separation were discussed in detail. The unique mechanism of the generation of EOF was explored in a glass microchannel using 1E-3MI-TFB aqueous solution as working electrolyte. A possible status of 1E-3MI cation in water was suggested at the first time, which facilitated the explanation of EOF and its characteristics in glass microchannel. Additionally, microchip electrophoresis using 1E-3MI-TFB aqueous solution was successfully applied to the chiral separation of complex enantiomers of dipeptides. RTILs aqueous solution, as the electrolyte for the separation of complicated optical isomers, could lead to a revolution in the analytical methods of chiral or conformational analysis for biomolecules.     

基于虫型碳纳米纤维的气敏薄膜传感器对工作场所氨气的高灵敏性检测

本文使用铝支持的铁催化剂,通过化学气相淀积方法合成了虫型碳纳米纤维;并把它以3：2的质量比与玻璃粉混合,借助松油醇的粘结,制备了薄膜传感器。使用扫描电镜和透射电镜对虫型碳纳米纤维,铁催化剂和传感器薄膜进行了形貌分析。最后在室温和常压下,采用新的检测方法在低电压（0-1伏）条件下进行了传感器的气敏测试,分析了它对氨气的灵敏性等特性。实验结果证实：在低浓度氨气条件下(0.175 mg/m³-0.35 mg/m³),基于虫型碳纳米纤维的薄膜传感器具有极高的灵敏性;经过反复的实验,证实薄膜传感器具有很高的稳定性,极快的反应时间(0.05 s)和恢复时间(1 min)。实验结果说明虫型碳纳米纤维是极好的气敏材料。     

Electrochemical redox reaction in a silica sol-gel glass with embedded organic electrolyte

The electrochemical redox reaction of ferrocene was studied in silica sol-gel glass with embedded organic electrolyte. This material has been prepared by mixing hydrolysed tetramethylorthosilicate sol with propylene carbonate LiClO₄ solution containing ferrocene and further gelation in a form of block or film. The electrochemical behaviour of encapsulated ferrocene was studied by cyclic voltammetry, chronoamperometry, differential pulse voltammetry and impedance spectroscopy on ultramicroelectrodes. The shape of the cyclic voltammograms corresponding to the electrooxidation of ferrocene in sol-gel block is similar to that obtained in liquid electrolyte and it does not depend on gel aging. The current substantially decreases during the first few days after gelation. Later it becomes weakly dependent on aging and the apparent diffusion coefficient of ferrocene in the gel block is about half of that in liquid electrolyte. The electrooxidation of ferrocene also occurs in film of the analogous sol-gel material cast on the surface of the electrode assembly.     

Characteristics of acrylic acid-grafted polyethylene prepared by photografting using mixed solvents consisting of water and organic solvent

Photografting of acrylic acid (AA) on linear-low density polyethylene film (thickness=30 μm) was investigated at 60 °C using mixed solvent consisting of water and organic solvents such as acetone and methanol. Xanthone was used as photoinitiator, which was coated on the film earlier. With longer photoirradiation time, such as 40 and 60 min, the percentage of grafting decreased with increasing the concentration of organic solvent in the mixed solvent, where formation of homopolymer occurred preferentially over the grafting reaction. In the system with photoirradiation of 20 min, on the other hand, a maximum percentage of grafting was observed at a certain concentration of organic solvent, in which formation of grafted polymer rather than homopolymer was emphasized. Photografting using the mixed solvent resulted in AA-grafted film with homogeneous distribution of grafted chains, exhibiting larger pH-responsive character, where the grafted film shrinks in an acidic medium, while it swells in an alkaline region. Polymer catalysts for hydrolysis of p-nitrophenylacetate, which was performed at 40 °C in water/ethanol (1/4, v/v)-mixed solvent at pH=9.0, could be prepared by reacting the AA-grafted film with L-histidine and its catalytic activity was slightly influenced by location of grafted chains.     

Fabrication and characterization of TiO2 photocatalytic thin film prepared from peroxo titanic acid sol

A novel sol–gel technique using the PTA (peroxo titanic acid) sol as precursor for the fabrication of TiO₂ photocatalytic thin film is introduced in this paper. The peroxo titanic acid sol was synthesized from titanyl sulfate (TiOSO₄), ammonia and peroxide solution (H₂O₂). The transparent and porous TiO₂ thin film was prepared via a sol–gel technique using PTA sol and polyethylene glycol (PEG) as precursor and template, respectively. The TiO₂ thin film samples were characterized by the X-ray diffraction (XRD), scanning electron microscopy (SEM), UV–visible spectrophotometry (UV–vis), X-ray photoelectron spectrum (XPS) and thermogravimetry and differential thermal analysis (TG-DTA) technique. The PTA sol displayed amorphous TiO₂ below 100 °C. The anatase phase formed at 200 °C to 700 °C. The crystallinity of anatase phase was improved with increasing temperature. The anatase crystals on the surface of TiO₂ film were strip-like, the size being about 100 nm in length and 40 nm in diameter. Addition of PEG to the PTA sol developed porous structures in the film and changed the size and shape of the particles. The surface of the film contained Ti, O and C elements and Na element that diffused into the film from the glass substrate. The photocatalytic performance of TiO₂ film was tested for the degradation of 10 mg/L methyl orange. The degradation of methyl orange solution reached 98.9% after irradiated for 180 min under UV light. The porous TiO₂ thin film exhibited high photocatalytic activity towards degrading methyl orange.     

Glass-liquid transition of vapor-deposited hexane studied using TOF-SIMS

Thermodynamic connection between liquid and glass is not obvious for poor glass formers. In this study, microscopic molecular diffusivity and macroscopic fluidity of vapor-deposited thin films of n-hexane were investigated using TOF-SIMS to elucidate the mechanism of the glass-liquid transition. The C 6H 14 film deposited at 15 K is characterized by a porous structure, as inferred from the intermixing with adsorbed C 6D 14 and D 2O molecules, as well as the formation of D 2O nanoclusters on the surface. The hexane molecules are reoriented at temperatures higher than 60-70 K, resulting in smoothing of the surface and densification of the film. Self-diffusion of the hexane molecules commences at 110 K; then, the film dewets the Ni(111) substrate after some aging time. Results indicate that ultraviscous liquid formed at the glass transition temperature of 110 K transforms into fluidized liquid immediately before crystallization. The D 2O molecules adsorbed onto the surface play a role as a surfactant, as evidenced by quenching the film dewetting. The ultraviscous liquid is likely to be a distinct phase, which might explain the absence of calorimetric glass transition for poor glass formers like hexane.     

水溶性丙烯酸酯类感光干膜的制备及其性能研究

用溶液聚合法合成了水溶性丙烯酸树脂,并以该树脂为成膜物质制备了水溶性感光干膜。傅立叶-红外光谱和¹HNMR分析表明,丙烯酸树脂中不含CC不饱和双键,基本不参与紫外光固化反应。感光干膜性能测试表明,干膜中丙烯酸树脂的酸值及重均分子量会影响干膜的解析度和附着力等性能。进一步的研究表明,曝光能量、感光级数和显影时间也会直接影响干膜的性能。以30 μm厚度干膜Ⅱ为例,为获得较好的性能,丙烯酸树脂中甲基丙烯酸含量范围为21.5%~23.8%,重均分子量范围为6.00×10⁴~7.54×10⁴,曝光能量设定40~60 mJ/cm²,感光级数为18~23/41^ST,显影时间40~50 s,在此条件下,干膜的解析度可以达到30 μm,附着力为20 μm,干膜线路的侧边形貌和尺寸稳定性良好。此外,感光干膜中丙烯酸酯的比例和种类也会影响干膜的各方面性能,通过调节干膜中各组分含量的比例可以优化干膜性能。     

Stress and Cracks in Gel-Derived Ceramic Coatings and Thick Film Formation

Residual stress was evaluated by measuring the substrate curvature for alkoxide-derived silica and titania films deposited on silica glass substrates. The residual stress was tensile, increasing with increasing heat-treatment temperature. The stress in fired films was affected greatly by water/alkoxide ratio and chelating agents in starting solutions. Secondly, in situ observation was made on cracking of gel films subjected to heat-treatment. Silica and titania gel films deposited on silicon wafers were cracked in the heating-up stage at temperatures of 100°–400°C, depending on the film thickness and heating rate. Larger thickness and lower heating rates were found to lower the cracking onset temperature. Finally, organic polymers with amide groups were demonstrated to increase the uncracking critical thickness. The polymers include polyvinylpyrrolidone and polyvinylacetamide, allowing single layer ceramic coating films over 1 m in thickness to be formed without cracking.     

黑膜厚度与膜表面张力关系的研究

用微干涉测量技术直接测定楔压等温线,研究了电解质浓度对阳离子表面活性剂TTAB在浓度大于cmc时形成黑膜厚度的影响及膜表面张力与溶液表面张力之间的差别.结果显示,黑膜厚度取决于楔压和电解质浓度,随着楔压的增加,液膜厚度减少至一定程度后几乎保持不变,表明黑膜类型的转化是阶跃式的,而电解质屏蔽了液膜两个表面电荷层间的排斥作用,故电解质浓度增加,液膜厚度变小.由楔压等温线得出的膜表面张力的结果说明一般黑膜的表面张力与溶液的表面张力并无明显差别.     

Sol–gel preparation of antireflective coatings at 351 nm with different thickness and improved moisture-resistance

Antireflective (AR) coatings at 351 nm with different thickness were designed and prepared by sol–gel process using tetraethylorthosilicate as precursor and ammonia as catalyst. The parameters of these coatings, including film thickness and refractive index, were calculated by optical formula and the coatings were prepared accordingly. Sol dilution method was used to adjust the film thickness. The wavelengths of maximum transmission measured by UV–Vis spectrophotometer, were used to monitor the film thickness. It was found that AR coatings with higher thickness possess better abrasion-resistance. Hydroxyl terminated polydimethylsiloxane (PDMS) was added into pure silica sol to improve both the abrasion-resistance and moisture-resistance of AR coating.     

相转移方法制备银纳米粒子单层膜

在油酸钠保护下用NaBH_4还原AgNO_3，制得了银纳料粒子胶体溶液。利用相转 移剂NaH_2PO_4等，使Ag纳料粒子在水／朋机相界面之间形成薄膜。形成的Ag纳料 粒子膜可以转移到玻璃等基质上，讨论了其转移机理；并用石英晶体微天平（QCM ）宣检测了银纳料粒子的相转移量。     

PMMA/超支化聚(酯-酰胺)共混物薄膜中柱状相结构的形成

利用相差显微镜、三维形貌测量仪对聚甲基丙烯酸甲酯 超支化聚 (酯 酰胺 ) (PMMA HBP)共混物薄膜在玻璃基板作用下的相分离行为进行了研究 .结果表明 ,不同组分比的共混物薄膜会呈现不同的相形态和相分离过程 .当薄膜厚度在 5 0 0nm左右 ,HBP为低组分时 ,发现了一种特殊的分散相为圆柱状的相形态 ,并对该相形态出现的条件进行了研究 .认为基板与组分之间的相互作用和薄膜厚度决定了圆柱状结构形成 .     

Preparation and Properties of Sol–Gel Thin Film Containing Rhodamine B Derivative with Ethoxy Silano Group on Organic Substrate and its Application to Surface-Treatment Thin Film for Display

A thin film containing rhodamine B derivative with ethoxy silano group was formed on organic film substrate using the sol–gel method. Rhodamine B derivative with a triethoxysilano group, SiO₂ sol and acrylic polymer having a triethoxy group were reacted in alcohol to give a coating solution for film formation, followed to be roll-coated on polyethylene terephthalate (PET) film and heat-treated at 130°C. This thin film consists of inorganic polymer (SiO₂), organic polymer (acrylic resin) and organic dye. These component parts become interconnected through mutual chemical bonding. This thin film has an absorption peak at 578 nm and superb water resistant characteristics (almost no dye elution in 50°C water for 150 min) as a result of chemical bonding between the organic dye and the matrix skeleton. It also has good flexibility. The film can be used as a wavelength-selective absorption film for displays to improve contrast.     

An Electrochemical Study on the Corrosion Inhibition of Stainless Steel by Polyaniline Film

Polyaniline(PANI)film was electrosynthesized on 304 stainless steel by cyclic voltammetry using aqueous oxalic acid as supporting electrolyte.The potential sweep rates were changed to achieve the PANI film with different thickness and structures.Protective properties of the PANI film for corrosion of stainless steel in 3% NaC1 aqueous solution were investigated by monitoring potentiodynamic polarization curves and electrochemical impedance spectroscopy(EIS).The results showed that the PANI film which was formed with lower sweep rate led to more positive shift of corrosion potential and greater charge transfer resistance,reflecting higher inhibition for corrosion of the stainless steel.     

New gelators of urea-containing triazine derivatives: effects of aggregation and optical features in different organic solvents

New gelators for urea-containing triazine derivatives were synthesised, and their gelation potential was examined using different organic solvents. These compounds were found to form the organogels with a variety of organic solvents, such as hexane and other solvents. The elongated alkyl tails of the gelators displayed an obvious decrease in the critical gelation concentrations of apolar solvents and an increase in the compatibility of gelation in polar solvents. The resulting thermo-reversible gels were characterised by using the dropping ball method and a number of other instruments. The melting temperature (Tm) of the gels in decalin and CCl₄ increased with the gelator concentrations. The intermolecular hydrogen bonding of gelation in different organic solvents was observed using an FT-IR spectrometer. Temperature-dependent UV–vis and fluorescence analysis showed that the organogels displayed diverse aggregations and various fluorescence effects in different organic solvents. Blue fluorescence and J-aggregation in decalin and the quenched effect and π–π stacking in CCl₄ were observed. Further, the morphological self-assembled feature in different organic solvents was studied with a scanning electron microscope, and the morphological features demonstrated that there were different aggregations in different solvents. In conductivity electrolyte experiments, the organogel electrolytes exhibited high conductivity (σ) compared with the corresponding tetrabutylammonium perchlorate (TBAP)/THF solution. The conductivity of the gel electrolytes increased with the concentration of the electrolyte salts and temperature. When the sol–gel temperature was achieved, a high ion conductivity was observed compared with the corresponding TBAP/THF solution. When the ratio of the added electrolyte salts exceeded 5%, gelation was inhibited. Furthermore, the effect of the electrolyte salts on the Tm of the gel was confirmed. The added electrolyte salts affected the gelation ability, but did not affect the sol–gel temperature.     

Chemical Solution Deposition of ZnO Thin Films by an Aqueous Solution Gel Precursor Route

An aqueous chemical solution deposition method was used to prepare thin films of ZnO on SiO₂/Si (1 1 1) substrates. Starting from an aqueous solution of Zn acetate, citric acid and ammonia, very thin films could be deposited by spin coating. Heating parameters, necessary for thin film annealing, were determined using FTIR experiments on dried gel precursors, heated up to different temperatures. The morphology and the thickness of the films were investigated by SEM. It is found that homogeneous thin films with grain sizes of about 20 nm are formed. XRD experiments show that there is an indication that the films, crystallized at 500°C, exhibit preferential grain growth along the c-axis.