复合电沉积的最新研究动态

综述近年来国内外复合电沉积技术最新研究动态．重点探讨纳米复合镀层，电催化复合镀层以及光活性复合镀层等方面的研究现状和发展趋势．纳米复合镀层比一般的复合镀层具有更高的硬度，更好的耐磨性和耐蚀性；电催化复合镀层则可在纯金属电极，合金电极的基础上进一步降低电极反应的过电位．以金属氧化物，导电聚合物作为基质材料的电催化复合镀层已为现代复合电沉积技术开辟了一个新领域．     

Zn-TiO2和Zn-Fe-TiO2纳米复合镀层中二氧化钛复合量的测定

近年来，利用纳米二氧化钛光催化剂降解有机废气及杀菌除污已成为环境污染治理的一个热点。以往研究的重点放在粉末状二氧化钛光催化剂上。由于粉末状二氧化钛光催化剂存在分离与回收的问题导致其无法工业化，而催化剂固载化技术则是解决这一问题的有效途径。其中利用电沉积技术或化学镀技术在金属器件上制备纳米二氧化钛复合镀层是一种较为有效的方法。复合镀层中二氧化钛的复合量直接影响其光催化能力的强弱。另外，纳米二氧化钛复合镀层与普通镀层相比还常具有更优异的力学性能和耐蚀性能。以往测定纳米复合镀层中二氧化钛（或其它纳米微粒）的复合量通常是用能谱分布仪（EDS），但该仪器价格昂贵，且属于微区分析，不能代表整个镀层中的平均含量，难于推广。本文建立了以二安替比林甲烷为显色剂，采用常规的分光光度法测定Zn—TiO2和Zn—Fe-TiO2纳米复合镀层中的二氧化钛复合量，方法简便可靠，易于普及。     

氧化锌-银复合纳米粒子的制备：吸收光谱和荧光光谱

金属和半导体纳米粒子的制备及性质的研究是当今材料科学和物理化学的热门课题［1－6］．在利用太阳能光降解环境污染物、生物传感器以及光生物等方面这些纳米粒子都具有实际应用的可能性．对纳米粒子表面进行修饰而形成的复合纳米粒子可以有效地调整单一颗粒的表面性质甚至颗粒的稳定性．另外，复合纳米粒子的制备对研究纳米粒子的尺寸量子化效应、非线性光学性质及其它光电性质都有重要的意义．人们已成功地制备了许多复合金属－金属纳米粒子，如Cu－Ag［7］，Ag-Pd［8］及Ag－Pt［9］等．关于复合半导体－半导作纳米粒子也有报导，如C…     

采用一锅法制备量子点/琼脂纳米复合凝胶

以天然高分子琼脂为稳定剂,采用简单便捷的一锅法制备Mn掺杂ZnS量子点/琼脂纳米复合凝胶,琼脂不仅作为制备量子点的稳定剂,同时也是纳米复合凝胶的主要成分。对该纳米复合凝胶中量子点的化学结构和尺寸大小进行了表征,并对纳米复合凝胶的荧光性能和凝胶性能进行了研究。实验结果表明,制备得到的纳米复合凝胶均一稳定,在302 nm紫外光下呈现十分明显的橙红色荧光。在该纳米复合凝胶的透射电子显微镜（TEM）表征中可以观察到大小比较均一、粒径为3 nm左右的纳米粒子,光谱分析结果进一步证实纳米复合凝胶中存在Mn掺杂ZnS量子点。该纳米复合凝胶不仅具有良好的荧光性能,还具有温度刺激响应性可逆溶胶-凝胶转变性能,同时具有较高的溶胶转变温度和较好的温度稳定性。利用这些性能特点,可以方便地制备纳米复合凝胶小球。此外,该纳米复合凝胶还可以被潜在应用于金属离子的荧光检测分析领域。     

核/壳型CdTe@SiO2荧光纳米复合粒子的制备与表征

利用反相微乳法, 以巯基乙酸修饰的水溶性CdTe量子点为核, 包覆SiO₂, 制备得到核壳型CdTe@SiO₂荧光纳米复合粒子. 用紫外-可见(UV-vis)分光光度计, 荧光(PL)分光光度计, 红外(FT-IR)光谱仪, 透射电子显微镜(TEM)等分析测试手段, 对得到的荧光纳米复合粒子的性能进行表征, 结果表明: 得到的CdTe@SiO₂纳米复合粒子是核壳型结构, 由SiO₂壳层包覆多个量子点, 其大小均匀, 水溶性好, 有效地提高了量子点的稳定性, 大大增强了其抗光漂白性能, 为该材料的进一步生物应用打下了良好的基础.     

Papain/HA-Phe自组装复合纳米粒子及乳化性能

用L-苯丙氨酸乙酯(L-Phe)改性透明质酸(HA)双亲性生物大分子(HA-Phe)负载生物活性分子木瓜蛋白酶(papain),HA-Phe和Papain通过静电、氢键和疏水相互作用自组装形成生物基Papain/HA-Phe复合纳米粒子.用动态光散射(DLS)和透射电镜(TEM)对复合纳米粒子的尺寸和形貌进行表征.结果显示,形成的复合纳米粒子为球形结构,粒径约308 nm.以此复合纳米粒子为颗粒乳化剂稳定白油,形成水包油型Pickering乳液.乳液的扫描电镜(SEM)显示,复合纳米粒子吸附在油水界面,形成复合纳米粒子的吸附层以稳定乳液.详细研究了pH和盐浓度对复合纳米粒子性质和复合纳米粒子乳化性能的影响.结果表明,随着pH增加,复合纳米粒子在油滴表面的吸附数目减少,乳化性能降低;随着盐浓度增加,复合纳米粒子的形变能力增强,乳化性能提高.进一步研究了乳液中木瓜蛋白酶的活性及美白效果.研究表明,制备的乳液保留了一定的活性,且具有一定的美白效果.     

纳米二氧化硅对镍电沉积影响及在复合镀层中的化学键合状态

用线性扫描伏安法和电位阶跃法研究了n-SiO2/Ni复合电刷镀体系的电化学响应，探讨了纳米颗粒的影响；用X射线光电子谱研究了复合镀层中n-SiO2/Ni颗粒表面与基质金属间的相互作用．结果表明纳米颗粒使金属沉积过电位显著降低，电流效率、金属成核率及晶体生长速度增加，纳米颗粒对金属镍电结晶有明显的催化效应；n-SiO2/Ni表面氧的不饱和化学键与表面扩散过程中吸附态金属Ni原子键合形成Ni-O键，纳米颗粒与基质镍以化学键方式结合．     

金属纳米粒子增强有机光电器件性能研究进展

金属纳米粒子以其特殊的体积效应、量子尺寸效应、表面效应和宏观量子隧道效应提供了诸多优异的光学和电学性能.实验表明,利用金属纳米粒子的光学和电学效应可以有效提升有机光电器件的综合性能.目前在有机发光二极管器件中流明效率最好的增强效果为150%,在有机光伏器件中功率转换效率最好的增强效果为70%,特别是在一些高效有机光电器件中的成功应用,虽然增强的比例相对较低,但是器件效率基数大,最终得到的器件性能相当优异.这些性能提升的主要机理包括表面增强荧光、等离激元光捕获、能量转移、电学效应、散射效应等.本文以金属纳米粒子的表面等离子体共振效应和电学效应为主线,按照不同纳米粒子及器件中的修饰位置进行分类,系统总结了金属纳米粒子提高有机发光二极管器件和有机光伏器件性能方面的工作.针对纳米粒子的局域表面等离子共振效应作用范围小,增强波长单一等问题,总结了一些新的设计思路如远场增强效应、纳米粒子和激子剖面的调控与匹配及散射增强效应等,希望为进一步的结构设计提供帮助.     

超声法制备硫化铅/二氧化硅核壳结构亚微米粒子

0 引言 纳米微粒具有的小尺寸效应,表面效应、量子尺寸效应及宏观量子隧道效应等导致纳米粒子的热、磁、光、敏感特性和表面稳定性等不同于常规粒子,这就使得它具有广阔的应用前景.     

纳米金刚石稳定水分散体系在复合电镀铬中的应用

研究纳米金刚石水基稳定分散体系的组成及分散操作工艺.以低泡沫磺酸基阴离子表面活性剂作分散活化剂,比较了各种机械搅拌方式对体系稳定性的影响,并以复合镀铬作应用试验.测定了纳米金刚石复合镀铬的镀层沉积速率,镀层硬度,耐磨性等参数,由SEM观察镀层晶态结构图像.列举了试验结果、测试数据及复合镀铬的工艺条件,并对实验结果及机理进行了分析探讨.     

复合镀层中ZrO2微粒对基质Ni晶体结构的影响

采用复合电沉积方法制备了Ｎｉ－ＺｒＯ２复合镀层，探讨了ＺｒＯ２微粒引起的基质金属Ｎｉ的晶体择优取向及点阵常数的变化，及其对析氢电催化活性的影响。结果表明，ＺｒＯ２微粒的存在改变了Ｎｉ的电沉积层结构，使基质金属Ｎｉ产生新的沿（２２０）晶面的择优取向。这一新的择优取向不利于析氢反应。择优取向的改变说明复合电沉积过程中，Ｎｉ与ＺｒＯ２微粒是以一定的界面匹配进入复合镀层的，基质金属Ｎｉ点阵参数的改变也证明     

ITO/TiO2表面电沉积CdS纳米粒子及其薄膜的光电性能

采用阴极恒电位沉积方法, 在TiO2表面沉积制备出CdS纳米粒子. XRD和SEM测试结果表明, CdS粒子的结构以六方晶相为主, 粒径分布均匀, 表面形貌呈菜花状. 通过调节沉积电位和沉积时间等因素在一定程度上可以控制CdS纳米粒子的生长. 随着沉积电位变负, CdS粒子的粒径逐渐减小. 沉积时间越短, 粒子粒径越小. 紫外-可见吸收光谱测试结果表明, 不同条件下制备出来的CdS粒子表现出一定的量子尺寸效应. 此外, 沉积条件也会影响ITO/TiO2/CdS复合半导体薄膜的光电性能.     

Electrodeposition and characterization of chromium–tungsten carbide composite coatings from a trivalent chromium bath

The electrodeposition of chromium from a trivalent chromium bath has been described in this work. The electrocomposite coatings of chromium with hard abrasive particles were investigated. The chromium–tungsten carbide (Cr? WC) composite coatings were obtained by suspending different concentrations of WC particles in a trivalent chromium plating solution to improve the various properties of the chromium deposit layers. The effect of operating conditions on the deposit layers has been studied. On the other hand, the effect of non‐ionic polymeric surfactant [nonyl phenol ethoxylate with 12 units of ethylene oxide (NPE)] as an additive in enhancing the incorporation of the WC ceramic particles in the chromium metal matrix was investigated. It was found that the co‐deposition of the WC ceramic particles depends on the concentration of the additive and its efficiency in reducing the surface tension of the electroplating solution. The mechanism of incorporation of WC particles into a growing deposit was suggested and discussed in view of the zeta potential and degree of wetability of WC particles in the plating solution. Furthermore, the adsorption behaviour of the additive on WC particles was analysed according to the Frumkin isotherm. The surface morphology and the distribution of WC in the chromium metal matrix were investigated. The properties of the deposit layers, hardness, corrosion resistance and wear resistance were determined and compared with free chromium deposits. The test results reveal that the Cr? WC deposit layer shows better performance compared with the chromium‐free deposit. Copyright © 2005 John Wiley & Sons, Ltd.     

Carbon nanofiber–copper composite powder prepared by electrodeposition

Carbon nanofiber–copper composite powder is prepared by an electrodeposition process using a copper plating bath containing homogeneously dispersed carbon nanofibers. Particles of the composite with a spiky ball structure are accumulated on the plating electrode during the initial stage of electroplating, and can be separated easily to give a powder carbon nanofiber–copper composite. The particle size can be controlled by selecting appropriate electroplating conditions.     

离子液体中18-冠醚-6添加剂对三价铬电沉积的影响

在1-丁基-3-甲基咪唑硫酸氢盐（[BMIM]HSO₄）电镀液中,探究了18-冠醚-6添加剂对电沉积铬的影响. 紫外-可见光谱结果表明,18-冠醚-6与Cr³⁺形成配合物,使最大吸收波长发生红移. 循环伏安研究表明,Cr³⁺的还原经历了两步. 18-冠醚-6的添加使Cr³⁺的峰电位和起始还原电位均正移了220 mV. 能谱仪（EDS）结果显示,在18-冠醚-6的作用下镀层中铬含量有所提高. 铬镀层的扫描电子显微镜（SEM）表征结果表明,加入18-冠醚-6后,所得镀层的颗粒变大. 18-Crown-6/CrCl₃/[BMIM]HSO₄/H₂O电镀液中工艺优化的结果为：在温度为50 ^oC、pH值为3.5、电流密度为1200 A·m^-2、电镀时间为1.5 h的最佳工艺条件下,铬镀层的厚度达到72.5 μm,电流效率为42.3%.     

Ultrasound technique as a tool for high-rate incorporation of Al<Subscript>2</Subscript>O<Subscript>3</Subscript> in NiCo layers

NiCo–Al₂O₃ composite coatings were prepared by electrodeposition in a sulfamate plating bath containing Al₂O₃ particles to be co-deposited under sonication. For reliable determination of the microstructure, detailed studies on composite cross-sections were carried out by energy-dispersive spectrometer (matrix composition, particle content) and FE-SEM/electron backscattered diffraction data (particle distribution, grain size), accompanied by XRD analyses concerning texture, lattice parameter, grain size, and residual stress. The NiCo matrix with a Co/Co + Ni ratio up to 0.4 is a face-centered cubic solid solution with <100> and <110> fiber textures. The distribution of the particles (size 250 nm) was well-dispersed and enhanced up to 15 wt.% by ultrasound application during plating. Vickers hardness increased up to 50% by dispersion hardening. First-order residual stress in the matrix increased with rising Co content, thus decreasing wear resistance and revealing the complex of composite properties with partially opposite effects.     

电沉积Ni-PSZ梯度镀层过程中阴极电流效率的研究

采用动电位扫描，电化学交流阻抗及扫描电子显微镜研究电沉积Ｎｉ－ＰＳＺ梯度镀层过程中阴极电流效率的变化规律及其机理．结果表明，Ｎｉ－ＰＳＺ复合镀层对氢的析出反应具有催化作用，在镀液中加入ＰＳＺ微粒后，能增大镍还原过电位，降低氢析出过电位，从而不断降低电沉积梯度镀层过程中的阴极电流效率．在电沉积Ｎｉ的过程中，有中间吸附相Ｎｉ＋ａｄｓ生成，ＰＳＺ微粒的加入能优先催化Ｈａｄｓ，加速氢气析出     

AFM study of the behavior of polystyrene and glass particles during the electrodeposition of copper

In this paper, the behavior of polystyrene and glass particles on a copper electrode during the electrodeposition of copper was studied using an atomic force microscope (AFM). Polystyrene or glass particles glued to the tip of the AFM cantilever were kept in contact with the surface of the electrode. The surface forces between the polystyrene or glass particle and the copper electrode were measured before, during, and after electrodeposition. These experiments revealed that glass particles do not make contact with the electrode, probably due to the repulsive hydration force. Polystyrene particles, on the other hand, make contact with the electrode, due to the attractive hydrophobic force. The AFM experiments were correlated with sedimentation co-deposition experiments of polystyrene and glass particles with copper. It was found that 80% of the polystyrene particles added to the plating solution incorporated with copper, while only 0.25% of the glass particles co-deposited under the same conditions.     

Preparation of Au/Ag multilayers via layer-by-layer self-assembly in spherical polyelectrolyte brushes and their catalytic activity

Spherical polyelectrolyte brushes(SPBs) consisting of polystyrene(PS) core and poly(2-aminoethyl methacrylate hydrochloride)(PAEMH) shell were prepared by photo-emulsion polymerization. Au nanoparticles(Au-NPs) with controlled size and size distribution were synthesized in situ using SPBs as nanoreactors. Via layer-by-layer deposition technique on the surface of SPBs, nano-composite particles with Au/Ag-NPs bilayer and Au/Ag/Au-NPs trilayer were prepared. The structures of the as-prepared Au/Ag multilayer SPBs were characterized by UV-Vis spectroscopy, TEM, ICP-AES and DLS. The charge reversal of the nano-composite particles observed by zeta potential confirmed the success of layer-by-layer assembly. The Au/Ag-NPs bilayer nano-composite particles showed high catalytic efficiency with an apparent activation energy of about 41.2 k J/mol in the reduction reaction of 4-nitrophenol to 4-aminophenol in the existence of sodium borohydride monitored. The catalytic activity of Au/Ag-NPs multilayer SPBs close to that of Au-NPs SPBs and much higher than that of Ag-NPs SPBs reveals its potential applications in cost-effective catalysts with high-performance.     

Mössbauer and XRD investigation of electrodeposited Fe,Co and Fe-Co alloys using a gluconate plating process

Summary A fundamental requirement for electrodeposition systems of the 21st century is that the processes involved should be environmentally safe, as well as they should be suited to replace hazardous conventional processes thereby supporting global sustainability. Conventional plating baths contain hazardous components and facilitate the generation of non-desirable compounds. The subject of the present article is the electrodeposition of Fe, Co, and Fe-Co alloys from an electrolyte based on gluconate. Preliminary studies showed that good quality iron-cobalt alloy coatings could be obtained on copper substrates from an environmentally acceptable gluconate plating system. The gluconate bath is inexpensive, non-toxic and easily disposed of. We report the successful deposition of Fe, Co and Fe-Co alloys from a modified gluconate based electrolyte which has not been used previously to deposit these materials. The effect of process parameters, such as current density, pH and deposition time were investigated using the gluconate electrolyte at a temperature of 60 °C and a pH of 7. The phase composition, crystal structure and magnetic anisotropy of the obtained alloy deposits are correlated with the applied process parameters. The structural analysis of the deposits is mainly based on ⁵⁷Fe CEMS and XRD measurements. α-Fe and Co-Fe were identified as dominant phases in Fe and Co/Fe deposits, respectively. The magnetic anisotropy of the Fe-containing deposits was found to correlate with the current density applied during deposition. The time of electrodeposition, at the same time, had little if any effect on the magnetic anisotropy of the obtained deposits. The mechanism and formation of the electrodeposits are discussed on the basis of the obtained results.