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Electroless Plating of Carbon Nanotubes with Copper 总被引:1,自引:0,他引:1
A simple chemical method was employed to coat carbon nanotubes with a layer of copper. Due to the hydrophobic nature, large surface curvature, small diameter and large aspect ratio, it is difficult to gain continuous electroless plating layer on the surface of carbon nanotubes. In this paper, a series methods (oxidization, sensiti-zation and activation) are used to add active sites before electroless plating, and the adjustment of the traditional composition of copper electroless plating bath and operating condition can decelerate electroless plating rate. The samples before and after coating were analyzed using transmission electron microscopy and energy-dispersive X-ray spectroscopy. The results showed that the surface of carbon nanotubes was successfully coated with continuous layer of copper, which lays a good foundation for applying carbon nanotubes in composites. 相似文献
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The scaling process of calcium carbonate on a low-energy heat transfer surface clectroless plating surface was investigated in a simulated cooling water system. Owing to the very low surface energy, the electroless plating surface exhibited less scaling susceptibility. A longer induction period and a lower scaling rate were obtained on the low-energy surface compared to copper surface under identical conditions. The calcite particles obtained on the electroless plating surface during the induction period were larger in size than those on copper surface because fewer cryst~s formed and grew at the same time on the |ow-energy surface. With increasing surface temperature, the induction period reduced and the scaling rate increased for the low-energy surface. When initial surface temperature was fixed, an increase in fluid velocity would reduce the induction period and increase the scaling rate due to the diffusion effect. However, when the heat flux was fixed, an increase in fluid velocity would decrease the surface temperature, and lead to a longer induction period and a lower scaling rate. The removal experiments of calcium carbonate scale indicated that during post induction period, the detachment was not obvious, while during the induction period, apparent removal of crystal particles was obtained on the electroless plating surface owing to the weak adhesion force. The more frequently the transient high hydrodynamic force acted, the more the detached crystal particles were. 相似文献
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The initial nickel deposition for the direct electroless nickel plating on non-catalytically active magnesium alloy is critical. The surface morphology and composition of the initial nickel plating coating are obtained by means of the scanning electron microscopy (SEM) and the energy dispersive X-ray (EDS). In addition, the mass gain/loss in the initial nickel deposition process was measured by using the electrobalance. The results showed that the MgO coating was gradually corroded by the plating solution, at the same time, MgF2 produced by F , H and MgO was deposited on the substrate during the initial electroless plating process. The nickel of the initial electroless plating was mostly growing on the boundary between the MgF2 coating and the MgO coating of the activation substrate, and then came to two sides. After that, the Ni-P coating growth rate to cover with the MgF2 coating was prior to the MgO coating. The electroless plating was in company with the substrate corrosion, but the electroless plating rate catalyzed by the exchanged nickel was more than the substrate corrosion rate. 相似文献
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The development of efficient bonding agents is one aspect of the advancement of refractories. Based on a newly developed binder system, a new generation of tarresin bonded magnesia carbon products with high performance has been developed. Furthermore, the binder system characterized by high carbon yield after carbonization results in forming an extremely strong carbon bonding. It can improve refractories properties to get new product with more advantages than old refractories: more economic, lower cost and low toxicity. Tar-resin is not only used in shaped refractories, but also in more refractories types, such as monolithic refractories. Immersion experiments of MgO- C monolithic refractories samples in liquid steel at 1600℃ have been carried out for steel making industry. These experiments showed the formation of a dense and continuous MgO rich layer, on the interface between refractory and steel, and the possible formation of inclusions as large clusters protruding from the refractory surface. For the mechanical properties, the powder was heated up to 1400℃ in air to remove carbon, and was subsequently formed into brick shape. Standard ASTM was used to determine the MOR, porosity and density. It is found that antioxidantmaterials play an important role in improving the mechanical properties. 相似文献
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Isolated single-walled carbon nanotubes with high proportion of opening tips were synthesized by using alcohol as carbon source. The mechanism of cutting action of oxygen was proposed to explain its growth. Compared with carbon nanotubes synthesized with benzene as carbon source, their specific surface area was heightened by approximately 2.2 times (from 200.5 to 648 m2/g) and the hydrogen storage capacity was increased by approximately 6.5 times (from 0.95 to 7.17%, w) which had exceeded DOE energy standard of vehicular hydrogen storage. 相似文献
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The separation between methane and nitrogen is an inevitable and important task in the C1 chemical technology and the utilization of methane from coalbed, yet it is considered to be one of the tough tasks in the field of separation. Pressure swing adsorption is a preferable technology if an adsorbent that allowing a large coefficient of separation for the CH4/N2 system is available. The separation coefficients between CH4 and N2 were obtained on analyzing the breakthrough curves measured experimentally with nine adsorbents. A technique of measuring the temperature-pulse was incorporated in the experiments, and the reliability of the result was improved. Superactivated carbon with large surface area and plenty of micropores was shown to have the largest separation coefficient and to be promising for the commercial utilization. 相似文献
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Palladium membranes were prepared on an a-alumina support by metal-organic compound chemical vapor deposition (MOCVD) method from palladium(Ⅲ) acetate precursor. Permeation properties of hydrogen and helium gas were studied as a function of the number of times of deposition of palladium on the peeling off phenomenon of palladium, which is common in electroless plated membrane, was observed. Silica was introduced into the pores to prevent the palladium grain from peeling off. The palladium-silica conjugated membrane does not show the peeling off phenomenon and can withstand the high temperature up to 800℃ which is the upper limit of our apparatus.The separation factor for hydrogen gas over carbon dioxide gas was improved with the increase of number of times of silica coating by sacrificing the H2 permeation and finally increased to four times. The improvement on the separation of hydrogen gas over carbon dioxide for pulladium-silica conjugated membrane was evaluated and a model of permeation pattern (palladium and silica) was proposed. This model suggests that the separation factor for hydrogen over carbon dioxide could be improved by introducing silica layer because the silica layer fills the pores and reduces the gas permeation without sacrificing the hydrogen permeation through the palladium region. These results indicate that the introduction of silica into the palladium grain is a promising means to improve the hydrogen separation performance of palladium based composite membranes. 相似文献
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Anode materials were used to construct microbial fuel cells(MFCs), and the characteristics of the anodes were important for successful applied performance of the MFCs. Via the cyclic voltammetry(CV) method, the experiments showed that 5 wt% multiwalled carbon nanotubes(MWNTs) were optimal for the PANI/MWNT film anodes prepared using 24 polymerization cycles. The maximum output voltage of the PANI/MWNT film anodes reached 967.7 mV with a power density of 286.63 mW·m~(-2). Stable output voltages of 860 mV, 850 mV, and870 mV were achieved when the anaerobic fluidized bed microbial fuel cell(AFBMFC) anodes consisted of carbon cloth with carbon black on one side, copper foam and carbon brushes, respectively. Pretreatment of the anodes before starting the AFBMFC by immersion in a stirred bacterial fluid significantly shortened the AFBMFC startup time. After the AFBMFC was continuously run, the anode surfaces generated active microbial catalytic material. 相似文献
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Thin palladium composite membranes were prepared by modified electroless plating method on a-alumina supports and a dense Pd/α-Al2O3 composite membrane with high hydrogen flux, good selectivity for hydrogen was obtained. It was tested in a single gas permeation system for hydrogen permeance and hydrogen selectivity over mtrogen. The hydrogen permeance of the corresponding membrane was ashigh as 2.45×10^-6mol·m^-2·s^-1.Pa^-1 and H2/N2 selectivityover700 at 623K and a pressure difference of 0.1MPa. The-main resistance of the composite membrane to H2 permeation lies in the aluminum ceramic support rather than the thin Pd layer. 相似文献
10.
The separation between methane and nitrogen is an inevitable and important task in the C1 chemical technology and the utilization of methane from coalbed, yet it is considered to be one of the tough tasks in the field of separation. Pressure swing adsorption is a preferable technology if an adsorbent that allowing a large coefficient of separation for the CH4/N2 system is available. The separation coefficients between CH4 and N2 were obtained on analyzing the breakthrough curves measured experimentally with nine adsorbents. A technique of measuring the temperature-pulse was incorporated in the experiments, and the reliability of the result was improved.Superactivated carbon with large surface area and plenty of micropores was shown to have the largest separation coefficient and to be promising for the commercial utilization. 相似文献
11.
采用以甲醛为还原剂的化学镀铜液,用硝酸银作活化剂,在碳纤维布表面沉积出连续、均匀、有光泽的化学镀铜层。研究了不同前处理工艺对碳纤维布化学镀铜的影响。采用扫描电子显微镜表征了化学镀铜层的表面形貌,并用数字电压表测试了碳纤维布化学镀铜前后的导电性。 相似文献
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TiB2表面镀铜工艺 总被引:4,自引:0,他引:4
利用化学镀覆技术成功在TiB2颗粒表面均匀化学镀覆铜。透射电子显微镜观察表明:通过严格的镀前预处理工艺的优化设计以增加活化点,对传统镀液配方的调整以降低镀速,能够成功地在TiB2颗粒表面镀覆一层铜,从而培强了其和铜基体之间的界面结合力,为TiB2在复合材料领域之中的应用打下了坚实基础。 相似文献
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化学镀银的应用与发展 总被引:2,自引:0,他引:2
综述了化学镀银的沉积机理及其发展概况,主要包括:铜粉化学镀银,空心玻璃微球化学镀银,碳纤维布化学镀银,碳纳米管化学镀银,Yb2O3粉体化学镀银,高分子材料表面化学镀银等;并对化学镀银的应用进行了阐述. 相似文献
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V.M. Dubin R. Akolkar C.C. Cheng R. Chebiam A. Fajardo F. Gstrein 《Electrochimica acta》2007,52(8):2891-2897
Various technical issues related to feature scaling and recent electrochemical technologies advances for on-chip copper interconnects at Intel are reviewed. Effects of additives on electroplating, as well as performance of novel Cu direct plating on ruthenium liner are discussed. An electroless cobalt capping layer of Cu lines, which led to increased electromigration resistance, has been characterized. The potential application of carbon nanotubes as future interconnects materials, their properties and controlled placement by using dielectrophoresis are also reviewed. 相似文献
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