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银表面组装有一系列自组装膜:3-巯基三甲氧基硅烷(3-MPT SAMs)、3-巯基三甲氧基硅烷与十八硫醇混合自组装膜(SAMM)以及两者之上分别自组装有乙烯基咔唑与甲基丙烯酸乙脂共聚物的复合自组装多层膜(CSAF(Ⅰ)和CSAF(Ⅱ)).这些惰性膜可作为金属表面的隔绝层.使用电化学阻抗(EIS)技术和X射线衍射(XRD)技术分析了表面修饰有这些自组装膜的银在10%氢氧化钠水溶液中的氧化阻力及其影响因素,发现自组装膜的存在不同程度地抑制了银表面的氧化反应,氧化过程存在2个以上时间常数. 相似文献
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目的：电化学合成过氧化氢(H2O2)是一种极具应用前景的分散式生产方法,但因传统的单极电合成电流效率不高,其发展受到了严重限制。本文旨在通过自组装单层膜修饰碳纤维纸制备高效二电子水氧化合成过氧化氢的阳极,同时耦合负载聚四氟乙烯/炭黑的自然空气扩散阴极,实现阴阳极同步电合成过氧化氢,从而大幅度提高其电流效率。创新点：1.通过自组装单层膜修饰碳纤维纸制备功能化阳极高效二电子水氧化合成过氧化氢;2.耦合阳极和阴极大幅度提高电合成过氧化氢的电流效率。方法：1.利用自组装单层膜修饰碳纤维纸制备功能化阳极,通过物化性能表征确定电极的结构特征(图1),并通过活性、选择性等指标考察电极的二电子水氧化性能(图2);2.制备负载聚四氟乙烯/炭黑的自然空气扩散阴极,并通过电化学性能表征确定最佳的物料配比(图3);3.耦合功能化阳极和自然空气扩散阴极,并通过电流效率、产率、稳定性等指标评估体系电合成过氧化氢的性能(图4和表1)。结论：1.利用自组装单层膜修饰碳纤维纸制备高效的二电子水氧化阳极;阳极过氧化氢的选择性为62.1%,产率为12.6μmol/(min·cm<... 相似文献
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讨论了随着铜电极在ODT溶液中浸泡时间的增长,成膜铜电极的腐蚀电阻、双电层电容的变化规律.结果表明ODT在铜表面30min内即可自组装形成致密、均匀、稳定的单分子膜. 相似文献
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王学杰 《浙江教育学院学报》2005,(4):1-6
采用电化学石英晶体微天平(EQCM)测量了金电极表面上聚二茂铁二甲基硅烷(PFDMS)膜在水、甲醇、乙醇和丙酮等溶液中循环伏安(CV)过程中的质量变化.在PFDMS膜的氧化还原过程中伴有电解质阴离子向膜内扩散,进出聚合物膜的阴离子量与发生氧化还原的Fe的物质量相等,在水溶液中ClO-4离子是非水化的,进入聚合物膜的ClO-4离子不带水分子,在有机溶剂中ClO-4离子是溶剂化的,在甲醇和乙醇溶液中分别有1:1和1:0.5等摩尔量的溶剂分子随阴离子进出聚合物膜. 相似文献
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1离子、小分子物质通过生物膜或磷脂分子的层数离子、小分子物质以跨膜方式(自由扩散、主动运输、协助扩散)通过生物膜。解答此类题目的方法是:明确所研究的物质运动的起点和止点→弄清物质通过的方式和经过的结构及其结构特点→注意一个等量关系“生物膜的层数=1/2磷脂分子的层数”。此外,还要明确细胞结构中,具有双层生物膜的结构有线粒体、叶绿体、核膜(有核孔),具有单层生物膜的结构有细胞膜、液泡膜、内质网、高尔基体、溶酶体。[例1]葡萄糖经小肠粘膜上皮进入毛细血管,需透过的磷脂分子层数是()A.4层B.6层C.8层D.10层[解析]葡萄糖是… 相似文献
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采用原子镶嵌(EAM)势,利用分子动力学方法研究了单个空位在Cu(100)表面及其附近区域扩散分子动力学过程,给出了空位在此表面附近不同层的形成能和迁移能.研究结果表明空位在表面形成能最小,随着层数增加空位形成能也增加,直到表面以下第五层达到体值.对于空位迁移,计算结果表明处于表面层附近的空位容易向上一层迁移直至迁移到表面. 相似文献
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采用接触角测试及扫描隧道显微镜(STM)分析测试了二元化合物[C8-TPP-(ip)Ru(phen)2](ClO4)2在高定向裂解石墨衬底上形成的自组装膜.接触角测试结果显示自组装膜具有较强的疏水性.STM观测结果发现[C8-TPP-(ip)Ru(phen)2](ClO4)2在石墨表面形成两种不同畴界的自组装形式,并初步分析了其形成的原因. 相似文献
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为进一步深化实验教学改革,培养学生的综合能力、实践能力、创新能力和科研探索精神,开设了由教师科研项目转化而来的设计性实验.介绍了聚电解质复合纳滤膜的制备及性能测试的原理和方法.学生可根据自己的思路选择不同的聚电解质,制备出不同的聚电解质复合纳滤膜.通过对膜性能的测试,初步了解聚电解质种类、聚电解质层数、组装顺序等对膜性能的影响. 相似文献
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界面反应已成为界面自组装构筑的一个重要反应方面.从自组装膜的形成及自组装膜的气相、液相、膜上分子交联反应以及膜表面大分子寡聚体的设计组装等几个方面的表面反应对近年来自组装膜构筑方面的进展予以分析和综述.引用文献23篇. 相似文献
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采用N一丁基吡啶六氟磷酸盐EBuPy]PF6和壳聚糖（Chi）作为修饰剂,通过静电吸附作用在玻碳电极表面形成稳定性较强的自组装膜修饰电极[BuPy]PF4-Chi／GC．采用电化学阻抗谱技术和循环伏安法研究自组装膜在K3[Fe（CN）4]-K4EFe（CN）6]溶液中的电化学行为,结果表明：形成的自组装膜对溶液与基底间的界面电子转移有强烈的阻碍作用,氧化还原峰电流与扫速的1／2次方在20～100mV／s的范围内呈良好的线性关系,表明该电极过程受扩散控制．该修饰电极对铜离子有很好的选择性,响应灵敏度相比于未修饰的电极提高60倍,铜离子的溶出线性伏安峰电流与其浓度在1．56×10“～6．25×10-4mol·L-1范围内呈良好的线性关系（R=0．9966）． 相似文献
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通过在底栅顶接触的喷墨打印有机薄膜晶体管的SiO2表面采用原子层沉积方式制备薄层的Al2O3修饰层,并与未修饰前进行比较,发现有源层在ALD-Al2O3修饰后的SiO2表面接触角大大变小,且喷墨打印的有源层线条变粗。而随着ALD-Al2O3修饰层厚度的增加,SiO2表面粗糙度变大。通过测试其电学性能,发现ALD- Al2O3修饰层厚度为1 nm时,OTFT的性能最好,与未修饰前相比,其迁移率提高了近8倍,而开关比提高约4个数量级。 相似文献
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A type of azobenzene-containing block copolymer polymethyl methacrylate-b-poly (n-butylmethacrylate-co-6-(4-(phenylazo) benzoate) hexyl methacrylate) (PMMA-b-(PnBMA-co-PAzoMA)) was synthesized by the atom transfer radical polymerization (ATRP). Macroinitiator polymethyl methacrylate (PMMA) was prepared by ATRP and used to initiate the copolymerization of monomer n-butyl methacrylate (nBMA) and azobenzene-based methacrylate monomer (AzoMA). Herein, three block copolymers with different molecular weights and block volume fractions were obtained and spin-coated on a silicon substrate or quartz plate before annealing at 180 °C for 14 h. The surface morphologies in these annealed copolymer films were observed by atomic force microscopy (AFM). Bicontinuous stripe or island patterns with different sizes were formed dependent on the film thickness. These ordered patterns are considered to be formed arising from the dewetting process of the surface layer in the copolymer film. Photoisomerization of azobenzene units in the copolymer films changed the dewetting behaviors of the surface layer of the thin film. Therefore, some copolymer annealed films showed a reversible morphology conversion between bicontinuous stripe and island structure when exposed to UV light and upon being stored in the dark. It was found that the composition of the block copolymer had obvious influences on the photoinduced morphology conversion behaviors in these copolymer thin films. When the volumes of PnBMA and PAzoMA phases in the block copolymer were large enough, the surface morphology could be modulated by UV light irradiation and storage in the dark. This work proposes a new possibility for photoinduced control and design of the dewetting processes of thin films using a linear block copolymer. 相似文献
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薄膜镀层由于厚度小，难以用通常的磨损方法评估其耐磨性。本文研究了采用精密凹坑研磨仪评价薄膜镀层耐磨性的方法，并对TaN/NbN纳米多层膜和TaN、NbN单层膜进行了磨损实验。结果表明，精密凹坑研磨仪是一种适用于评价薄膜镀层耐磨性的方法。TaN/NbN纳米多层膜有TaN、TbN单层膜更高的耐磨性。 相似文献
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ZHANG Yun-lian LI Qi-ling 《浙江大学学报(A卷英文版)》2006,7(8):1447-1452
INTRODUCTION Steel rebar embedded in concrete is protectedagainst corrosion by the thin passive film on its sur-face and the physical protection from concrete. Thealkaline environment (pH≥12.5) of the concrete poresolution triggers passivation on the rebar surface andformation of the protective oxide film. The physicaprotection of concrete coverage hinders the invasionof aggressive agents. However, this passivity can bebroken down by local pH loss as a result of concretecracking or the… 相似文献
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Amorphous InGaZnO (a-IGZO) film is deposited on the glass substrate by radio-frequency sputtering and the influence of annealing on wet etch of a-IGZO films were investigated.The results show that etch rate of IGZO films decrease with the increase of annealing temperature.Etching taper angle is less than 60 and critical dimension (CD) loss is less than 1 μm in over-etching time of 30 s.The fact implies that IGZO films etching with oxalic acid may be a good wet etching way for the thin-film transistor (TFT) ... 相似文献
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Amorphous InGaZnO (a-IGZO) films were deposited on the corning eagle XG (EXG) glass substrates using magnetron sputtering
method. The structure, surface morphology, electrical and optical properties of these films were investigated by X-ray diffraction
(XRD), scanning electron microscopy (SEM), semiconductor parameter analyzer and spectrophotometry, respectively. The influence
of oxygen flow on the electrical properties of IGZO thin films was studied, showing that increasing oxygen flow changes the
resistivity with six orders of magnitude. The contact resistance of ITO/IGZO is 7.35×10−2 Ω·cm2, which suggests that a good ohmic contact exists between In2O3: Sn (ITO) and IGZO film. 相似文献
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Aluminum nitride (AIN) thin films with high c-axis orientation have been prepared on a glass substrate with an A1bottom electrode by radio frequency (RF) reactive magnetron sputtering. Based on the analysis of Berg's hysteresis model, the improved sputtering system is realized without a hysteresis effect. A new control method for rapidly depositing highly c-axis oriented AIN thin films is proposed. The N2 concentration could be controlled by observing the changes in cathode voltage, to realize the optimum processing condition where the target could be fixed stably in the transition region, and both stoichiometric film composition and a high deposition rate could be obtained. Under a 500 W RF power of a target with a 6 cm diameter, a substrate temperature of 450 ℃, a target-substrate distance of 60 mm and a N2 concentration of 25%, AIN thin film with prefer-ential (002) orientation was deposited at 2.3 μm/h which is a much higher rate than previously achieved. Through X-ray diffraction (XRD) analysis, the full width at half maximum (FWHM) of AIN (002) was shown to be about 0.28°, which shows the good crystallinity and crystal orientation of AIN thin film. With other parameters held constant, any increase or decrease in N2 con-centration results in an increase in the FWHM of AIN. 相似文献