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Experimental Investigations on Electroless Deposition of Copper on Basalt Fibers  [PDF]
S. Ezhil Vannan
Journal of Minerals and Materials Characterization and Engineering (JMMCE) , 2015, DOI: 10.4236/jmmce.2015.34031
Abstract: In this work, an electroless method of coating copper on the basalt short fibers using copper sulphate solution is described. In order to avoid any interfacial reactions in the basalt fiber reinforced metal matrix composites, the basalt fibers were coated with copper. The effects of the time of sensitization, activation, metallization, PdCl2 concentration, pH and temperature bath on the extent of copper coating on basalt fiber are reported. The conditions used for electroless coating were optimized to obtain a uniform and continuous layer of copper. Using this method, it is possible to deposit up to about 25 wt% copper on the basalt fiber. The resultant composite fiber was characterized by scanning electron microscopy (SEM)/energy-dispersive X-ray (EDX) during and after the coating process. The effects of the thickness of copper coating on surface condition and also the tensile strength of the basalt fibers have been investigated. The study of surface condition of the coated basalt fibers by SEM showed that the copper coating at the thickness of about 0.2 μm had the best continuity on the basalt fibers. The results of tensile tests of basalt fibers coated with different thickness of copper showed that increasing the thickness of coating layer decreased the overall strength of fibers.
Precipitate assemblies formed on dislocation loops in aluminium-silver-copper alloys  [PDF]
Julian M. Rosalie,Laure Bourgeois,Barrington C. Muddle
Physics , 2012, DOI: 10.1080/14786430903066959
Abstract: The precipitation microstructure of the \gamma' (AlAg2) intermetallic phase has been examined in aluminium-silver-copper alloys. The microstructure developed in an Al-0.90at.%Ag-0.90at.%Cu alloy was significantly different from that reported for binary Al-Ag alloys. The orientation relationship between the matrix and precipitate was unchanged; however, the \gamma' phase formed as aggregates with a two-dimensional open assemblies. Each such assembly contained two variants of the \gamma' phase alternately arranged to form a faceted elliptical unit. The \theta' (Al2Cu) phase formed on these assemblies after further ageing. The faceted elliptical assembly morphology has not been previously reported for the \gamma' precipitate. The change in precipitation behaviour was attributed to copper modifying the as-quenched defect structure of the matrix. This precipitation morphology clarifies earlier observations on the precipitate number density and mechanical properties of aluminium-silver-copper alloys.
A study of the initial stages of the electrochemical deposition of metals on foreign substrates: Lead and thallium on copper and silver surfaces: General discussion  [PDF]
Jovi?evi? Jovan N.,Bewick Alan
Facta Universitatis Series : Physics, Chemistry and Technology , 2005, DOI: 10.2298/fupct0502183j
Abstract: The basic applicability of the UPD theory of Gerischer et al. has been confirmed in the case of lead and thallium deposition on copper and silver single crystals, but it was shown also that this is only one of the important factors. It was established that the effect of substrate structure on the mechanism of the UPD monolayer formation plays an important role in the addition to the effect of electronegativity difference between the substrate and depositing atoms. An effect of changing the concentration of depositing metal and specifically adsorbing anion were found and attributed to the changes in the electronegativity of the substrate and underpotential layer as a result of changing the electrode potential. It was conclusively proven by the analysis of the peaked current-time transients obtained by potential step measurements and the very sharp voltammetry peaks, that first order 2D phase transformations are possible in UPD systems. It was also found that the L.S.V. peaks reflecting such processes must not be expected to be free from the influence of slow kinetics. It was established that the 2D crystalline metal-like phases with the closest-packed epitaxial structure exist as a stable, final product in UPD. Moreover, the possibility of higher order 2D transformations in UPD has been given strong support by the evidence of gradual monolayer density change with increasing driving force. Lead UPD on vitreous carbon was found to be the result of substrate reconstruction induced by the repeated deposition and dissolution leading to surface condition changes favoring deposition of the first layer. UPD monolayers on copper and silver surfaces always preceded OPD and had a profound effect on its nucleation overpotential (making it very small indeed) or even changing its character from 3D into 2D (in the case of vitreous carbon substrate). It was also shown that lead and thallium OPD on copper and silver single crystals starts off by charge transfer controlled instantaneous 3D nucleation and subsequent growth of 3D centers. Finally, the results obtained in the experiments performed have shown that electrochemical techniques can prove very suitable in the study of 2D phase transformation kinetics and that their further employment in this field should prove particularly rewarding.
Influence of both the composition of impregnation solution and impregnation method on copper(II), chromium(VI) and silver(I) deposition on activated carbon
Ivanovi? Slavica,?ivanovi? Aleksandar S.,Bo?njakov Gordana
Hemijska Industrija , 2003, DOI: 10.2298/hemind0301001i
Abstract: The composition of a solution for impregnating activated carbon (AC) for use in a gas filter was investigated. The solution components were tetraaminocop-per(II) complex, chromium(VI), silver(l) and carbonate ions. Two methods of impregnation were investigated: ion adsorption from aqueous solution in excess and the incipient wetness method. Copper, chromium and silver con-tents on AC Were determined by atomic absorption spectrometry. The largest copper contents (4.38 and 5.00 % (w/w for two AC samples) were achieved at: c([Cu(NH3)4]2+) = 1.0 mol/L; M(Cu) i M(Cr) = 3.75: 1; M(Cu) i M(Ag) = 62: 1 and M(Cu): M(CO3) = 2: 1, using two fold impregnation by the incipient wetness method with 2.4 mL of solution per 3 g AC. The contents of chromium and silver on the same AC samples Were 1.06 and 0.0098 % for the first and 1.14 and 0.009 % for the second AC. A larger Cr content (1.57 %) was achieved from an impregnation solution in excess (c([Cu(NH3)4]2+) = 1.25 mol/L; M(Cu) i M(Cr) = 3: 1; without Ag). The largest Ag content (0.17 %) was obtained using two fold impregnation by the incipient wetness method (c([Cu(NH3)4]2+) = 0.8 mol/L; M(Cu): M(Cr) = 3.75: 1<; M(Cu) i M(Ag) ( 80: 1 and M(Cu) i M(CO3) = 1 i 1.32). Larger metal contents were obtained using two fold impregnation by the incipient wetness method. Further work is needed on the determination of the influence of carbonate ions both on the solution stability and metal deposition on AC.
ELECTROLESS COPPER PLATING ON FRAXINUS MANDSHURICA VENEER USING GLYOXYLIC ACID AS REDUCING AGENT  [PDF]
Lijuan Wang,Lili Sun,Jian Li
BioResources , 2011,
Abstract: Copper coating was deposited on Fraxinus mandshurica veneers for preparing EMI shielding composite by electroless plating using glyoxylic acid as reducing agent in the solution. XPS and SEM were used to analyze the activation process. It was found that a continuous chitosan membrane was loaded on the wood surface. XPS results showed that Pd(II) ions were chemically adsorbed on a chitosan membrane on the wood surface through an N-Pd σ coordination bond. After reduction, part of Pd(II) absorbed formed very little Pd(0) particles on the chitosan-treated wood surface. The activated wood veneers were immersed into a plating bath in which copper film was successfully initiated. The coatings were characterized by SEM-EDS, XPS, and XRD. The metal deposition, surface resistivity, and electromagnetic shielding effectiveness were measured. The morphology of the coating was uniform, compact, and continuous. The wood grains were preserved on the plated wood veneer, which had a copper-like color and sheen. EDS, XPS, and XRD results indicated that the coating consisted of Cu0 with crystalline structure. The surface resistivity and copper deposition reached 175.14 mΩ cm-2 and 21.66 g/m2 when the veneer was pretreated with 0.8 % chitosan for 8 min and plated for 30 min at 55 oC. The plated veneers exhibited good electromagnetic shielding effectiveness of over 60 dB in frequency ranging from10 MHz to 1.5 GHz.
STUDY OF POLYPYRROLE FILMS MODIFIED WITH COPPER AND SILVER MICROPARTICLES BY ELECTROCHEMICAL CEMENTATION PROCESS
Arrieta Almario,álvaro A; Vieira,Roberto L;
Journal of the Chilean Chemical Society , 2006, DOI: 10.4067/S0717-97072006000300009
Abstract: electroactive polypyrrole (ppy) films obtained under potentiostatic electropolimerization from aqueous solutions of pyrrole doped with sulfate (so42-) anions were modified by incorporation of copper (cu) and silver (ag) microparticles using electrochemical cementation process. the electrochemically deposited and dissolving processes metals (cu and ag) onto and from polypyrrole were investigated. the ppy-cu and ppy-ag electrodes were characterized by electrochemical techniques and scanning electron microscopy (sem) analysis and the electrochemical response of these modified electrodes was compared to that of the unmodified polypyrrole electrode. the results indicate that two forms of metal, valence and elemental ones, can be formed on polypyrrole at a constant cathodic potential. however, only the valence metal can be left on polypyrrole at the anodic potential. the copper and silver particles interact with polypyrrole films involving a strong complex formation affecting its electrochemical behavior. scanning electron microscopy measurements show that dendritic-like metal aggregates are formed on the film surface. the electrochemical experiments reveal that metal deposition on conducting polymer can be envisaged as an attractive method for the electrodes fabrication
STUDY OF POLYPYRROLE FILMS MODIFIED WITH COPPER AND SILVER MICROPARTICLES BY ELECTROCHEMICAL CEMENTATION PROCESS  [cached]
álvaro A Arrieta Almario,Roberto L Vieira
Journal of the Chilean Chemical Society , 2006,
Abstract: Electroactive polypyrrole (PPy) films obtained under potentiostatic electropolimerization from aqueous solutions of pyrrole doped with sulfate (SO4(2-)) anions were modified by incorporation of copper (Cu) and silver (Ag) microparticles using electrochemical cementation process. The electrochemically deposited and dissolving processes metals (Cu and Ag) onto and from polypyrrole were investigated. The PPy-Cu and PPy-Ag electrodes were characterized by electrochemical techniques and scanning electron microscopy (SEM) analysis and the electrochemical response of these modified electrodes was compared to that of the unmodified polypyrrole electrode. The results indicate that two forms of metal, valence and elemental ones, can be formed on polypyrrole at a constant cathodic potential. However, only the valence metal can be left on polypyrrole at the anodic potential. The copper and silver particles interact with polypyrrole films involving a strong complex formation affecting its electrochemical behavior. Scanning electron microscopy measurements show that dendritic-like metal aggregates are formed on the film surface. The electrochemical experiments reveal that metal deposition on conducting polymer can be envisaged as an attractive method for the electrodes fabrication
Deposition of Nanofilms by the Electroless Method
Khoperia T.,Gakhokidze R.
Proceedings of the International Conference Nanomaterials : Applications and Properties , 2012,
Abstract: In the result of application of the developed technology, Au, Ag and Pd were adequately replaced with non-precious metal alloys. The nanotechnologies using the electroless deposition are much more advantageous and simpler than other expensive methods of nanotechnology and allow the fabrication of photocatalysts and catalysts by means of deposition of nanocrystals having the specified properties on high-dispersive powder like semiconductors.
STUDY OF ELECTROLESS COPPER PLATING FROM COPPER-GLYCERIN COMPLEX SOULTION
甘油铜络合物溶液化学镀铜的研究

WANG Hong-xian,ZHAO Hong-kun,
王鸿显
,赵红坤

腐蚀科学与防护技术 , 2007,
Abstract: The factors affecting the deposition rate of copper and stability of electroless copper plating solution were investigated. The formulation of bath solution and processing parameters were established by the research. The results show that the proposed bath solution was highly stabile, by which cupper plating had high deposition rate with good appearence. Therefore, the copper-glycerin camplex solution shows a good prospect for copper plating.
A review of electroless gold deposition processes
Hassan O. Ali,Ian R. A. Christie
Gold Bulletin , 1984, DOI: 10.1007/BF03214674
Abstract: The literature on electroless gold deposition processes is reviewed both with respect to bath formulation and the kinetics of the electrochemical reduction and oxidation reactions involved. Some modified formulations are discussed in more detail and components processed by the use of electroless gold deposition are illustrated.
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