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Sample records for auto-catalytic electroless plating

  1. LASER INDUCED SELECTIVE ACTIVATION UTILIZING AUTO-CATALYTIC ELECTROLESS PLATING ON POLYMER SURFACE

    DEFF Research Database (Denmark)

    Zhang, Yang; Nielsen, Jakob Skov; Tang, Peter Torben;

    2009-01-01

    This paper presents a new method for selective micro metallization of polymers induced by laser. An Nd: YAG laser was employed to draw patterns on polymer surfaces using a special set-up. After subsequent activation and auto-catalytic electroless plating, copper only deposited on the laser tracks....... Induced by the laser, porous and rough structures are formed on the surface, which favours the palladium attachment during the activation step prior to the metallization. Laser focus detection, scanning electron microscopy (SEM) and other instruments were used to analyze the topography of the laser track....... Characterization of the deposited copper layer was used to select and improve laser parameters. Several types of polymers with different melting points were used as substrate. Using the above mentioned laser treatment, standard grades of thermoplastic materials such as ABS, SAN, PE, PC and others have been...

  2. Electroless Plating on Plastic Induced by Selective Laser Activation

    DEFF Research Database (Denmark)

    Zhang, Yang; Tang, Peter Torben; Hansen, Hans Nørgaard;

    2009-01-01

    surface property’s point of view, the basic polymer surface tends to attract palladium in an acidic solution. Using the laser treatment mentioned above, standard grades of thermoplastic materials such as ABS, SAN, PE, PC and others have been successfully metalized. The metalized tracks are down to 300 μm......This paper presents a new method for selective micro metallization of polymers. A Nd:YAG laser is employed to draw patterns on polymer surfaces that are submerged in a liquid (usually water). After subsequent activation with palladium chloride and followed by auto-catalytic electroless plating......, copper deposit only on the laser tracks. The mechanism of the palladium activation step is analyzed based on experimental results and theoretical calculations. It is believed that the laser introduces porous and rough structures on the surface, which favours the palladium attachment. Looking from the...

  3. Hydrogen Recombination Rates of Plate-type Passive Auto-catalytic Recombiner

    International Nuclear Information System (INIS)

    The hydrogen mitigation system may include igniters, passive autocatalytic recombiner (PAR), and venting or dilution system. Recently PAR is commonly used as a main component of HMS in a NPP containment because of its passive nature. PARs are categorized by the shape and material of catalytic surface. Catalytic surface coated by platinum is mostly used for the hydrogen recombiners. The shapes of the catalytic surface can be grouped into plate type, honeycomb type and porous media type. Among them, the plate-type PAR is well tested by many experiments. PAR performance analysis can be approached by a multi-scale method which is composed of micro, meso and macro scales. The criterion of the scaling is the ratio of thickness of boundary layer developed on a catalytic surface to representative length of a computational domain. Mass diffusion in the boundary layer must be resolved in the micro scale analysis. In a lumped parameter (LP) analysis using a system code such as MAAP or MELCOR, the chamber of the PAR is much smaller than a computational node. The hydrogen depletion by a PAR is modeled as a source of mass and energy conservation equations. Te catalytic surface reaction of hydrogen must be modeled by a volume-averaged correlation. In this study, a micro scale analysis method is developed using libraries in OpenFOAM to evaluate a hydrogen depletion rate depending on parameters such as size and number of plates and plate arrangement. The analysis code is validated by simulating REKO-3 experiment. And hydrogen depletion analysis is conducted by changing the plate arrangement as a trial of the performance enhancement of a PAR. In this study, a numerical code for an analysis of a PAR performance in a micro scale has been developed by using OpenFOAM libraries. The physical and numerical models were validated by simulating the REKO-3 experiment. As a try to enhance the performance of the plate-type PAR, it was proposed to apply a staggered two-layer arrangement of the

  4. Hydrogen Recombination Rates of Plate-type Passive Auto-catalytic Recombiner

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jongtae; Hong, Seong-Wan [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Kim, Gun Hong [Kyungwon E-C Co., Seongnam (Korea, Republic of)

    2014-10-15

    The hydrogen mitigation system may include igniters, passive autocatalytic recombiner (PAR), and venting or dilution system. Recently PAR is commonly used as a main component of HMS in a NPP containment because of its passive nature. PARs are categorized by the shape and material of catalytic surface. Catalytic surface coated by platinum is mostly used for the hydrogen recombiners. The shapes of the catalytic surface can be grouped into plate type, honeycomb type and porous media type. Among them, the plate-type PAR is well tested by many experiments. PAR performance analysis can be approached by a multi-scale method which is composed of micro, meso and macro scales. The criterion of the scaling is the ratio of thickness of boundary layer developed on a catalytic surface to representative length of a computational domain. Mass diffusion in the boundary layer must be resolved in the micro scale analysis. In a lumped parameter (LP) analysis using a system code such as MAAP or MELCOR, the chamber of the PAR is much smaller than a computational node. The hydrogen depletion by a PAR is modeled as a source of mass and energy conservation equations. Te catalytic surface reaction of hydrogen must be modeled by a volume-averaged correlation. In this study, a micro scale analysis method is developed using libraries in OpenFOAM to evaluate a hydrogen depletion rate depending on parameters such as size and number of plates and plate arrangement. The analysis code is validated by simulating REKO-3 experiment. And hydrogen depletion analysis is conducted by changing the plate arrangement as a trial of the performance enhancement of a PAR. In this study, a numerical code for an analysis of a PAR performance in a micro scale has been developed by using OpenFOAM libraries. The physical and numerical models were validated by simulating the REKO-3 experiment. As a try to enhance the performance of the plate-type PAR, it was proposed to apply a staggered two-layer arrangement of the

  5. Study of electroless nickel plating on PerFactoryTM rapid prototype model

    Directory of Open Access Journals (Sweden)

    J.C. Rajaguru

    2012-12-01

    Full Text Available This paper presents an investigation of electroless nickel plating on PerFactoryTM rapid prototype model built on PerFactoryTM R05 material. PerFactoryTM R05 is acrylic based photo sensitive resin. It is a popular material in rapid prototyping using PerFactoryTM method which employs addictive manufacturing technique to build prototypes for visual inspection, assembly etc. Metallization of such a prototype can extend the application envelop of the rapid prototyping technique as they can be used in many functional applications. Unlike the electroless nickel plating on metal substrate, the process on acrylic resin substrate is not auto-catalytic. Hence, etching and activation are necessary for initiating the process. The final coating is then investigated using scanning electron microscope (SEM together with energy dispersive spectroscopy (EDS and x-ray diffraction (XRD analysis to identify the morphology and structure of the coating. The SEM & EDS analysis on surface and chemical composition of model surface after each preliminary surface treatment are also presented. Finally the layer is tested on Vickers micro hardness tester.

  6. Electroless metal plating of plastics

    Science.gov (United States)

    Krause, Lawrence J.

    1984-01-01

    Process for plating main group metals on aromatic polymers is carried out by the use of a nonaqueous solution of a salt of an alkali metal in a positive valence state and a main group metal in a negative valence state with contact between the solution and polymer providing a redox reaction causing the deposition of the main group metal and the reduction of the polymer. Products from the process exhibit useful decorative and electrical properties.

  7. Electroless nickel plating on polymer particles.

    Science.gov (United States)

    Fujii, Syuji; Hamasaki, Hiroyuki; Takeoka, Hiroaki; Tsuruoka, Takaaki; Akamatsu, Kensuke; Nakamura, Yoshinobu

    2014-09-15

    Near-monodisperse, micrometer-sized polypyrrole-palladium (PPy-Pd) nanocomposite-coated polystyrene (PS) particles have been coated with Ni overlayers by electroless plating in aqueous media. Good control of the Ni loading was achieved for 1.0 μm diameter PPy-Pd nanocomposite-coated PS particles and particles of up to 20 μm in diameter could also be efficiently coated with the Ni. Laser diffraction particle size analysis studies of dilute aqueous suspensions indicated that an additional water-soluble colloidal stabilizer, poly(N-vinyl pyrrolidone), in the electroless plating reaction media was crucial to obtain colloidally stable Ni-coated composite particles. Elemental microanalysis indicated that the Ni loading could be controlled between 61 and 78 wt% for the 1.0 μm-sized particles. Scanning/transmission electron microscopy studies revealed that the particle surface had a flaked morphology after Ni coating. Spherical capsules were obtained after extraction of the PS component from the Ni-coated composite particles, which indicated that the shell became rigid after Ni coating. X-ray diffraction confirmed the production of elemental Ni and X-ray photoelectron spectroscopy studies indicated the existence of elemental Ni on the surface of the composite particles. PMID:24998053

  8. Electroless nickel plating on optical fiber probe

    Institute of Scientific and Technical Information of China (English)

    Li Huang; Zhoufeng Wang; Zhuomin Li; Wenli Deng

    2009-01-01

    As a component of near-field scanning optical microscope (NSOM),optical fiber probe is an important factor influncing the equipment resolution.Electroless nickel plating is introduced to metallize the optical fiber probe.The optical fibers are etched by 40% HF with Turner etching method.Through pretreatment,the optical fiber probe is coated with Ni-P film by clectrolcss plating in a constant temperature water tank.Atomic absorption spectrometry (AAS),scanning electron microscopy (SEM),and energy dispersive X-ray spectrometry (EDXS) are carried out to charaeterizc the deposition on fiber probe.We have rcproducibly fabricated two kinds of fiber probes with a Ni-P fihn:aperture probe and apertureless probe.In addition,reductive particle transportation on the surface of fiber probe is proposed to explain the cause of these probes.

  9. Direct electroless nickel plating on silicon surface

    Institute of Scientific and Technical Information of China (English)

    HU Guanghui; WU Huihuang; YANG Fangzu

    2004-01-01

    Direct electroless nickel plating on n-Si(100)wafers in alkaline solutions was demonstrated without any activation procedure in advance, the effect of pH and temperature of the solutions on size of metal particles in deposits was examined, and also the element contents of deposits were analyzed by energy disperse spectroscopy (EDS). The results indicated that the size of metal particles increases with increasing temperature or decreasing pH. The possible mechanism of nickel deposition on n-Si(100) was discussed in terms of semiconductor electrochemistry, and the formation of nickel seed crystal on Si was mainly attributed to the generation of atomic hydrogen by electron capture of water molecule from the semiconductor in alkaline solutions.

  10. Electroless copper coating of epoxide plates in an ultrasonic field.

    Science.gov (United States)

    Touyeras, F; Hihn, J Y; Doche, M L; Roizard, X

    2001-07-01

    This paper reports the study of ultrasonic irradiation effects on electroless copper coating on an epoxide resin. Several parameters were monitored, such as plating rates, practical adhesion and internal stress, versus varying acoustic powers at a constant frequency of 530 kHz. Exposure conditions were characterised by both transmitted power and interfacial mass transfer coefficients. Optimum conditions expressed in irradiation time and power were determined. The use of ultrasound during electroless copper plating affects the plating rates and the deposits properties, particularly the practical adhesion which increases whereas the internal stress decreases. Then, the changes in the coating mechanisms are discussed. PMID:11441612

  11. Facile fabrication of silver nanofin array via electroless plating.

    Science.gov (United States)

    Miyoshi, Kentaro; Aoki, Yoshitaka; Kunitake, Toyoki; Fujikawa, Shigenori

    2008-04-15

    The fabrication of metallic nanostructures is one of the main issues in nanotechnology. This article describes the fabrication of a silver nanofin array by combining microlithography, electroless plating, and an etching technique. Fabricated Ag nanofins have a high aspect ratio (height/width = 10, width = 60 nm, height = 600 nm), and their widths and heights can be controlled by the period of electroless plating and the height of the original line pattern. An isolated Ag nanofin was proven to show metallic electrical conductivity. The current process provides a rapid and shape-designable fabrication method of metallic nanostructures. PMID:18312009

  12. Electroless Ni-B plating for electrical contact applications

    OpenAIRE

    C. T. Dervos; Vassiliou, P.; Novakovic, J.

    2005-01-01

    Electroless Ni-B plating has been tried on steel substrate in an effort to employ low-cost starting materials for electrical contacts or connectors. By selected conditions of heat treatment in a high vacuum environment the plating can acquire Cr-equivalent hardness without the effluents of the hard chromium plating process. The surfaces were characterized under scanning electron microscope and by XRD. The fabricated materials were tested under corrosion conditions by polarization measurements...

  13. Electroless plating apparatus for discrete microsized particles

    Science.gov (United States)

    Mayer, Anton

    1978-01-01

    Method and apparatus are disclosed for producing very uniform coatings of a desired material on discrete microsized particles by electroless techniques. Agglomeration or bridging of the particles during the deposition process is prevented by imparting a sufficiently random motion to the particles that they are not in contact with each other for a time sufficient for such to occur.

  14. Electroless plating of copper on surface-modified glass substrate

    Energy Technology Data Exchange (ETDEWEB)

    Su Wei, E-mail: aaasuwei@yahoo.com.cn [College of Chemistry and Life Science, Guangxi Teachers Education University, Nanning 530001 (China); Yao Libei; Yang Fang [College of Chemistry and Life Science, Guangxi Teachers Education University, Nanning 530001 (China); Li Peiyuan, E-mail: lipearpear@yahoo.cn [College of Pharmacy, Guangxi Traditional Chinese Medical University, Nanning 530001 (China); Chen Juan; Liang Lifang [College of Chemistry and Life Science, Guangxi Teachers Education University, Nanning 530001 (China)

    2011-07-01

    This work focuses on developing a novel convenient method for electroless copper deposition on glass material. This method is relied on the formation of amino (NH{sub 2})-terminated film on the surface of glass substrate, by coating polyethylenimine (PEI) on glass matrix and using epichlorohydrin (ECH) as cross-linking agent. The introduced amino groups can effectively adsorb the palladium, the catalysts which could initiate the subsequent Cu electroless plating, onto the glass substrate surface. Finally, a copper film is formed on the palladium-activated glass substrate through copper electroless plating and the surface-coppered glass material is therefore acquired. X-ray diffraction (XRD), atomic force microscope (AFM), scanning electron microscopy (SEM) images combined with energy diffraction X-ray (EDX) analysis demonstrate the successful copper deposition on the surface of glass substrate.

  15. Electroless plating of copper on surface-modified glass substrate

    International Nuclear Information System (INIS)

    This work focuses on developing a novel convenient method for electroless copper deposition on glass material. This method is relied on the formation of amino (NH2)-terminated film on the surface of glass substrate, by coating polyethylenimine (PEI) on glass matrix and using epichlorohydrin (ECH) as cross-linking agent. The introduced amino groups can effectively adsorb the palladium, the catalysts which could initiate the subsequent Cu electroless plating, onto the glass substrate surface. Finally, a copper film is formed on the palladium-activated glass substrate through copper electroless plating and the surface-coppered glass material is therefore acquired. X-ray diffraction (XRD), atomic force microscope (AFM), scanning electron microscopy (SEM) images combined with energy diffraction X-ray (EDX) analysis demonstrate the successful copper deposition on the surface of glass substrate.

  16. Electroless plating of copper on surface-modified glass substrate

    Science.gov (United States)

    Su, Wei; Yao, Libei; Yang, Fang; Li, Peiyuan; Chen, Juan; Liang, Lifang

    2011-07-01

    This work focuses on developing a novel convenient method for electroless copper deposition on glass material. This method is relied on the formation of amino (NH2)-terminated film on the surface of glass substrate, by coating polyethylenimine (PEI) on glass matrix and using epichlorohydrin (ECH) as cross-linking agent. The introduced amino groups can effectively adsorb the palladium, the catalysts which could initiate the subsequent Cu electroless plating, onto the glass substrate surface. Finally, a copper film is formed on the palladium-activated glass substrate through copper electroless plating and the surface-coppered glass material is therefore acquired. X-ray diffraction (XRD), atomic force microscope (AFM), scanning electron microscopy (SEM) images combined with energy diffraction X-ray (EDX) analysis demonstrate the successful copper deposition on the surface of glass substrate.

  17. Study on electroless 103Pd-plating process

    International Nuclear Information System (INIS)

    Using ϕ0.5 mm × 3.0 mm carbon rod as substrate, PdCl2 as precursor, 103Pd as radioactive tracer, and hydrazine as reductant, the process of electroless 103Pd-plating was studied. The results show that the optimum conditions of electroless 103Pd-plating are 2 g/L PdCl2, 65 g/L Na2EDTA, 700 mL/L 25%NH3 · H2O, 100 mL/L 5% H4N2 · H2O, pH=10, t=90 min, and the temperature of 50 ℃. The solution has good stability. The electroless 103Pd-plating is easy to carry out. About 95% 103Pd is deposited and 12% activity is shielded by the carbon rod. The utilization rate of 103Pd in the chemical adsorption reaction is high. 103Pd-coating is grey and smooth. 103Pcoating on each substrate of carbon rod is uniform, and the reaction can be repeated well. The technology of electroless 103Pd-plating can be applied in preparation of 103Pd seed and 103Pd-125I hybrid seed which is a new member of brachytherapy. (authors)

  18. ELECTROLESS NICKEL PLATING ON CHITOSAN-MODIFIED WOOD VENEER

    OpenAIRE

    Lijuan Wang; Haibing Liu

    2011-01-01

    An activation process involving chitosan was conducted to prepare electroless nickel plated wood veneers for electromagnetic interference (EMI) shielding. In this process Pd(Ⅱ) ions were chemically adsorbed on wood surface modified with chitosan. Then they were reduced and dipped into a plating bath in which Ni-P co-deposition was successfully initiated. The coatings were characterized by SEM-EDS and XRD. The metal deposition, surface resistivity, and electromagnetic shielding effectiveness w...

  19. Electroless plating of Ni thin films using foam of electrolyte

    Science.gov (United States)

    Furuhashi, Takahiro; Yamada, Yoshiyasu; Ichihara, Shoji; Takai, Akihiro; Usui, Hiroaki

    2016-02-01

    Electroless plating of Ni thin films was achieved in foam of electroplating solution in place of electroplating liquid. Commercial hypophosphite-based solution for Ni electroless plating was added with a surfactant of sulfuric acid monododecyl ester sodium salt (SDS) and bubbled with nitrogen gas to produce airy foam. Ni thin films were deposited by immersing iron substrates in the foam. Although stationary foam was inconvenient for electrodeposition by itself, film growth was enhanced by generating a flow of foam using substrate rotation and by adding SDS to a concentration of 0.1 to 0.3 wt %. No defects attributed to pinholes were observed on the film surface. This method was effective in reducing the net amount of plating solution necessary for film deposition.

  20. REVIEW ON ELECTROLESS PLATING Ni–P COATINGS FOR IMPROVING SURFACE PERFORMANCE OF STEEL

    OpenAIRE

    HONGYAN ZHANG; JIAOJUAN ZOU; NAIMING LIN; BIN TANG

    2014-01-01

    Electroless plating has been considered as an effective approach to provide protection and enhancement for metallic materials with many excellent properties in engineering field. This paper begins with a brief introduction of the fundamental aspects underlying the technological principles and conventional process of electroless nickel–phosphorus (Ni–P) coatings. Then this paper discusses different electroless nickel plating, including binary plating, ternary composite plating and nickel plati...

  1. Electroless silver plating on tetraethoxy silane-bridged fiber glass

    International Nuclear Information System (INIS)

    Tetraethoxy silane was used to functionalize the surface of fiber glass (FG) for adsorption with the electroless plated silver shell. The performance of electroless silver plated FG with tetraethoxy silane modification was compared to that of unmodified FG in terms of mechanical and electrical properties. The silane bridge provided more stability for binding with different concentrations of electroless plating silver ions. The characterization was investigated by using field emission scanning electron microscope (FESEM), X-ray diffraction patterns (XRD), energy-dispersion X-ray (EDX), metal microscope (MM) and electric resistance. The Ag coating on TEOS modified FG was more durable than that of unmodified FG in the ball milling test, as confirmed by the data of electric resistance and residue weight. The optimized conditions for producing the Ag coating FG were also investigated. The Ag-Si-FG-3-c product in this study has the lowest electrical resistance of 1.56 × 103 Ω/cm2 and good mechanical stability as exhibited in ball milling tests.

  2. Electroless silver plating on tetraethoxy silane-bridged fiber glass

    Energy Technology Data Exchange (ETDEWEB)

    Lien, Wan-Fu [Department of Cultural Heritage Conservation, National Yunlin University of Science and Technology, 123, Section 3, University Road, Touliu, Yunlin 640, Taiwan (China); Huang, Po-Chen [Department of Chemical and Materials Engineering, National Yunlin University of Science and Technology, 123, Section 3, University Road, Touliu, Yunlin 640, Taiwan (China); Tseng, Shi-Chang [Department of Mechanical Engineering, National Yunlin University of Science and Technology, 123, Section 3, University Road, Touliu, Yunlin 640, Taiwan (China); Cheng, Chia-Hsiang; Lai, Shih-Ming [Department of Chemical and Materials Engineering, National Yunlin University of Science and Technology, 123, Section 3, University Road, Touliu, Yunlin 640, Taiwan (China); Liaw, Wen-Chang, E-mail: liawwc@hotmail.com [Department of Chemical and Materials Engineering, National Yunlin University of Science and Technology, 123, Section 3, University Road, Touliu, Yunlin 640, Taiwan (China)

    2012-01-15

    Tetraethoxy silane was used to functionalize the surface of fiber glass (FG) for adsorption with the electroless plated silver shell. The performance of electroless silver plated FG with tetraethoxy silane modification was compared to that of unmodified FG in terms of mechanical and electrical properties. The silane bridge provided more stability for binding with different concentrations of electroless plating silver ions. The characterization was investigated by using field emission scanning electron microscope (FESEM), X-ray diffraction patterns (XRD), energy-dispersion X-ray (EDX), metal microscope (MM) and electric resistance. The Ag coating on TEOS modified FG was more durable than that of unmodified FG in the ball milling test, as confirmed by the data of electric resistance and residue weight. The optimized conditions for producing the Ag coating FG were also investigated. The Ag-Si-FG-3-c product in this study has the lowest electrical resistance of 1.56 Multiplication-Sign 10{sup 3} {Omega}/cm{sup 2} and good mechanical stability as exhibited in ball milling tests.

  3. Electroless silver plating on tetraethoxy silane-bridged fiber glass

    Science.gov (United States)

    Lien, Wan-Fu; Huang, Po-Chen; Tseng, Shi-Chang; Cheng, Chia-Hsiang; Lai, Shih-Ming; Liaw, Wen-Chang

    2012-01-01

    Tetraethoxy silane was used to functionalize the surface of fiber glass (FG) for adsorption with the electroless plated silver shell. The performance of electroless silver plated FG with tetraethoxy silane modification was compared to that of unmodified FG in terms of mechanical and electrical properties. The silane bridge provided more stability for binding with different concentrations of electroless plating silver ions. The characterization was investigated by using field emission scanning electron microscope (FESEM), X-ray diffraction patterns (XRD), energy-dispersion X-ray (EDX), metal microscope (MM) and electric resistance. The Ag coating on TEOS modified FG was more durable than that of unmodified FG in the ball milling test, as confirmed by the data of electric resistance and residue weight. The optimized conditions for producing the Ag coating FG were also investigated. The Ag-Si-FG-3-c product in this study has the lowest electrical resistance of 1.56 × 103 Ω/cm2 and good mechanical stability as exhibited in ball milling tests.

  4. Copper plating on the polyimide film by electroless plating techniques for EMI shielding.

    Science.gov (United States)

    Ji, Eun Sun; Cha, Hyun Gil; Kim, Chang Woo; Kang, Dong In; Kang, Young Soo

    2009-12-01

    In this work, the metal plated film was prepared by electroless plating techniques. The film was prepared for the fabrication of EMI shielding. Polyimide film was treated by base solution for etching and then activated by silver. The modified polyimide film was immersed into the electroless copper plating solution which has different molar ratios of nickel in the solution. The thickness and surface morphology of copper layer on the polyimide films were characterized with scanning electron microscopy (SEM). Furthermore, EMI shielding ability of the film was calculated by measuring reflectivity of EM wave on the film surface using the equation of Schelkunoff theory. PMID:19908729

  5. Method for regeneration of electroless nickel plating solution

    Science.gov (United States)

    Eisenmann, Erhard T.

    1997-01-01

    An electroless nickel(EN)/hypophosphite plating bath is provided employing acetic acid/acetate as a buffer and which is, as a result, capable of perpetual regeneration while avoiding the production of hazardous waste. A regeneration process is provided to process the spent EN plating bath solution. A concentrated starter and replenishment solution is provided for ease of operation of the plating bath. The regeneration process employs a chelating ion exchange system to remove nickel cations from spent EN plating solution. Phosphites are then removed from the solution by precipitation. The nickel cations are removed from the ion exchange system by elution with hypophosphorous acid and the nickel concentration of the eluate adjusted by addition of nickel salt. The treated solution and adjusted eluate are combined, stabilizer added, and the volume of resulting solution reduced by evaporation to form the bath starter and replenishing solution.

  6. Electroless nickel plated graphite fibers and surface behavior in Gr(Ni)/6061Al composite

    Institute of Scientific and Technical Information of China (English)

    WANG Chun-yu; WU Gao-hui; ZHANG Qiang; ZHANG Yun-he; XIU Zi-yang; CHEN Guo-qin

    2006-01-01

    The electroless nickel plated graphite fibers reinforced aluminum matrix composites (Gr(Ni)/Al) were produced by squeeze casting, and the microstructure of Gr(Ni)/Al composite and surface behavior of Ni-P coating were studied. The optimum process of electroless Ni-P plating included: burning to get rid of glue→degreasing→neutralization→acidulating→sensitizing→activation→electroless plating. The surface analysis results show that the electroless nickel plating can diffuse into the graphite fiber surface during the squeeze casting, and the Ni-P coating and aluminum alloys can produce brittle phase NiAl3 or NiAl. The X-ray diffraction(XRD) results indicate that Al4C3 is so little that no Al4C3 peaks are found, and the harmful hl4C3 can be decreased by the electroless plating Ni-P coating. The coating improves the interfacial bonding of continuous graphite fibers reinforced aluminum matrix composites.

  7. Electroless copper plating using dimethylamine borane as reductant

    Institute of Scientific and Technical Information of China (English)

    Yong Liao; Shengtao Zhang; Robert Dryfe

    2012-01-01

    Electroless copper plating was studied using dimethylamine borane (DMAB) as reductant and 1,5,8,12-tetraazadodecane as additive and triethanolamine (TEA) as buffer.The effects of pH,temperature and concentrations of reactants and additives on the anodic oxidation of DMAB and the cathodic reduction of copper ion were investigated.Experimental results indicate that high pH values (10-12.5) promote the oxidation of DMAB,and suppress the reduction of the copper ion,while high bath temperatures (55-70℃)accelerate both anodic oxidation and cathodic reduction.Increase of the Cu2+ and DMAB concentrations can improve the deposition rate of copper plating.Results for a dual-chelating-agent system indicate that 1,5,8,12-tetraazadodecane plays an important role in chelation,while the main effect of TEA is adsorption on copper surfaces to inhibit DMAB oxidation and to promote deposition.

  8. Electroless Nickel Plating and Electroplating on FBG Temperature Sensor

    Institute of Scientific and Technical Information of China (English)

    SHEN Ren-sheng; TENG Rui; LI Xiang-ping; ZHANG Jin; XIA Dao-cheng; FAN Zhao-qi; YU Yong-sen; ZHANG Yu-shu; DU Guo-tong

    2008-01-01

    Metal-coated fiber Bragg grating(FBG) temperature sensors were prepared via electroless nickel(EN) plating and tin electroplating methods on the surface of normal bare FBG.The surface morphologies of the metal-coated layers were observed under a metallographic microscope.The effects of pretreatment sequence,pH value of EN plating solution and current density of electroplating on the performance of the metal-coated layers were analyzed.Meanwhile,the Bragg wavelength shift induced by temperature was monitored by an optical spectrum analyzer.Sensitivity of the metal-coated FBG(MFBG) sensor was almost two times that of normal bare FBG sensor.The measuring temperature of the MFBG sensor could be up to 280 ℃,which was much better than that of conventional FBG sensor.

  9. Studies on Properties and Structure of Electroless Plating Tin Coating

    Institute of Scientific and Technical Information of China (English)

    XU Rui-dong; GUO Zhong-cheng; ZHU Xiao-yun

    2004-01-01

    The composition and structure of electroless tin coating were analyzed by SEM and X-ray diffraction. In the meantime, porosity, solderability and extensibility were determined by physical and chemical methods. The results showed that the porosity of the tin coating increases with the rise of bath temperature and decreases as the plating time rises. Solderability is improved with the rise of thickness of tin coating, and decreases when the tin deposit is heated at 180 ~ 200 ℃. The crystalline grain size becomes bigger and bigger with increasing plating time or bath temperature or coating thickness. X-ray diffraction indicates that only Cu and β-Sn phases show up in the diffraction patterns. Tin coating has a strong joint force with copper substrate and excellent function of electrochemical protection as anode coating.

  10. Synthesis of bimetallic nanoshells by an improved electroless plating method.

    Science.gov (United States)

    Liu, J B; Dong, W; Zhan, P; Wang, S Z; Zhang, J H; Wang, Z L

    2005-03-01

    In the Letter, we demonstrate an improved electroless plating method for the synthesis of bimetallic shell particles. The procedure involves a combination of surface reaction, seeding growth, and removal of supporting cores. We modified ammonical AgNO3 in ethanol with a controlled amount of HCHO in the seeding process and a uniform and relatively dense coverage of silver nanoparticle seeds on colloid cores was achieved. Following the second kind of metal plating, we extended this method to prepare continuous bimetallic core-shell and hollow particles with a submicrometer diameter. The morphologies of the bimetallic Cu/Ag and Pt/Ag particles were studied with transmission electron microscopy and scanning electron microscopy, and their crystallinity and chemical composition were confirmed by X-ray diffraction. The prepared materials may be of applied value in areas such as catalysis, optics, and plasmonics. PMID:15723456

  11. Review on Electroless Plating Ni-P Coatings for Improving Surface Performance of Steel

    Science.gov (United States)

    Zhang, Hongyan; Zou, Jiaojuan; Lin, Naiming; Tang, Bin

    2014-04-01

    Electroless plating has been considered as an effective approach to provide protection and enhancement for metallic materials with many excellent properties in engineering field. This paper begins with a brief introduction of the fundamental aspects underlying the technological principles and conventional process of electroless nickel-phosphorus (Ni-P) coatings. Then this paper discusses different electroless nickel plating, including binary plating, ternary composite plating and nickel plating with nanoparticles and rare earth, with the intention of improving the surface performance on steel substrate in recent years in detail. Based on different coating process, the varied features depending on the processing parameters are highlighted. Separately, diverse preparation techniques aiming at improvement of plating efficiency are summarized. Moreover, in view of the outstanding performance, such as corrosion resistance, abrasive resistance and fatigue resistance, this paper critically reviews the behaviors and features of various electroless coatings under different conditions.

  12. ELECTROLESS NICKEL PLATING ON CHITOSAN-MODIFIED WOOD VENEER

    Directory of Open Access Journals (Sweden)

    Lijuan Wang

    2011-04-01

    Full Text Available An activation process involving chitosan was conducted to prepare electroless nickel plated wood veneers for electromagnetic interference (EMI shielding. In this process Pd(Ⅱ ions were chemically adsorbed on wood surface modified with chitosan. Then they were reduced and dipped into a plating bath in which Ni-P co-deposition was successfully initiated. The coatings were characterized by SEM-EDS and XRD. The metal deposition, surface resistivity, and electromagnetic shielding effectiveness were measured. The morphology of the coating observed by SEM was uniform, compact, and continuous. EDS results showed that the coating consists of 1.8 wt.% phosphorus and 98.2 wt.% nickel. XRD analysis indicated that the coating was crystalline, which is supposed to be related to the low phosphorus content. The plated birch veneers exhibited electro-conductivity with surface resistivity of 0.24 Ω•cm-2 and good electromagnetic shielding effectiveness of over 50 dB in frequency range from10 MHz to 1.5 GHz.

  13. Effects of ultrasonic irradiation on the properties of coatings obtained by electroless plating and electro plating.

    Science.gov (United States)

    Touyeras, F; Hihn, J Y; Bourgoin, X; Jacques, B; Hallez, L; Branger, V

    2005-01-01

    This paper deals with the effects of ultrasonic irradiation on electroless copper coating i.e. metallic deposition on non-conductive substrates and on electroplating on metallic substrates. Ultrasonic irradiation was both applied during activation (surface preparation for the electroless coating) and during plating steps in both cases. Several parameters were monitored, such as plating rates, practical adhesion, hardness, internal stress versus varying acoustic powers and frequencies. Optimum conditions for irradiation time, frequency and power were determined for each step. It appears clearly that ultrasound use affects deposit properties. Then, changes in the coating mechanisms can be discussed, and several parameters will be explored in this paper, to explain enhancement of deposit properties: increase in catalyst specific area, stirring dependence, surface energy evolution, dihydrogen desorption, structure of coating. PMID:15474947

  14. Electroless plating of thin gold films directly onto silicon nitride thin films and into micropores.

    Science.gov (United States)

    Whelan, Julie C; Karawdeniya, Buddini Iroshika; Bandara, Y M Nuwan D Y; Velleco, Brian D; Masterson, Caitlin M; Dwyer, Jason R

    2014-07-23

    A method to directly electrolessly plate silicon-rich silicon nitride with thin gold films was developed and characterized. Films with thicknesses coating planar, curved, and line-of-sight-obscured silicon nitride surfaces. PMID:24999923

  15. Functionalization of particles and selective functionalization of surfaces for the electroless metal plating process

    OpenAIRE

    Mondin, Giovanni

    2014-01-01

    Electroless plating is a metal deposition technique widely used in the coating industry. It is the method of choice to plate substrates with complex geometries and nonconductive surfaces, such as polymers and ceramics, since it is based on a chemical reduction in solution rather than on an external electrical energy source like the electroplating method. Among others, examples of well-established applications are the electroless deposition of decorative metal coatings such as gold and silver,...

  16. Investigation of peculiarities of electroless copper plating systems using hydroxycarboxylic acids as Cu(II) ligands

    OpenAIRE

    Kepenienė, Virginija

    2012-01-01

    Electroless metal coating technique is one of the elegant ways of metal coating by controlling the temperature and pH of the plating bath in which there is no usage of electric current. The industrial electroless copper plating solution containing formaldehyde as reducing agent are known from the middle of the last century and are widespread in the practice up to now. However many chemical compounds used in such kind technological processes are hazardous for total environment, therefore the e...

  17. Copper deposition on Pd membranes by electroless plating

    Energy Technology Data Exchange (ETDEWEB)

    Acha, E.; Arias, P.L.; Cambra, J.F. [Chemical Engineering and Environmental Department, University of the Basque Country, UPV/EHU, 48013 Bilbao (Spain); Van Delft, Y.; Overbeek, J. [Energy Research Centre of the Netherlands ECN, Petten (Netherlands)

    2011-10-15

    PdCu membranes were prepared by the electroless plating of Pd membranes prepared on ceramic tubular supports. Different PdCu membranes were prepared with Pd content between 45 and 77 wt% and a total metal layer between 0.5 and 1.9 {mu}m thickness. The alloying step was performed in two ways to compare and establish the required alloying time for obtaining high permeance membranes. The alloying was analysed with EDX composition measurements, and full alloying was not required to obtain a stable hydrogen flux. Finally, permeance tests were performed at different pressures, including temperature cycles in hydrogen and nitrogen, to observe membrane stability. The hydrogen permeance values of the membranes were high, between 1.5x10{sup -3} and 4.5x10{sup -3} mol/(s Pa{sup 0.5} m{sup 2}) at 673 K. The membranes recorded stable permeance values even after thermal cycles in a hydrogen atmosphere. Metal layer thickness was calculated using both the weight difference method and SEM images. SEM images were also used to analyse the surface morphology of the membranes, which was generally fairly uniform and smooth.

  18. Electroless Ni-B plating for electrical contact applications

    Directory of Open Access Journals (Sweden)

    Dervos, C. T.

    2005-12-01

    Full Text Available Electroless Ni-B plating has been tried on steel substrate in an effort to employ low-cost starting materials for electrical contacts or connectors. By selected conditions of heat treatment in a high vacuum environment the plating can acquire Cr-equivalent hardness without the effluents of the hard chromium plating process. The surfaces were characterized under scanning electron microscope and by XRD. The fabricated materials were tested under corrosion conditions by polarization measurements. Semispherical nickel plated steel joints were tested in a computer controlled contact make-break apparatus, under simultaneous application of a mechanical and a low-voltage electrical load for 20,000 cycles. After heat treatment the plating acquires a crystalline structure with very good adhesion to the substrate material. Corrosion decreases and increased hardness is obtained. The surface is also characterized by good electrical properties during aging accelerated tests.

    Se ha investigado la deposición de Ni-B por vía química sobre un substrato de acero, con el fin de poder emplear materiales de bajo coste para los contactos o conectores eléctricos. Mediante condiciones específicas de tratamiento térmico en un ambiente de alto vacío, la deposición puede alcanzar durezas equivalentes al cromo (Cr sin los efluentes del proceso de cromado duro. Las superficies se caracterizaron en el microscopio electrónico de barrido y mediante DRX. Los materiales fabricados se ensayaron bajo condiciones de corrosión utilizando mediciones de polarización. Se ensayaron las juntas semiesféricas de acero niquelado en un equipo de contactos controlado por ordenador bajo la aplicación simultánea de una carga mecánica y de una carga eléctrica de bajo voltaje durante 20.000 ciclos. Después del tratamiento térmico, el recubrimiento adquiere una estructura cristalina con muy buena adherencia al material del substrato. Se consigue una menor corrosión y mayor

  19. Electroplating zinc transition layer for electroless nickel plating on AM60 magnesium alloys

    Institute of Scientific and Technical Information of China (English)

    WANG Xiao-min; ZHOU Wan-qiu; HAN En-Hou

    2006-01-01

    Electroplating zinc coating as transition layer of electroless nickel plating on AM60 magnesium alloys was investigated. The zinc film can be deposited in a pyrophosphate bath at 50-60 ℃ under current density of 0.5-1.5 A/dm2. A new fore treatment technology was applied by acid cleaning with a solution containing molybdate and phosphorous acid, by alkaline cleaning in a bath containing molybdate and sodium hydroxide. The subsequent electroless plating was carried out in nickel sulfate bath. The SEM observation shows that the deposition is uniform and compact. The polarization curve measurements show that the corrosion potential of the zinc plating in 3.5% NaCl is about -1.3 V(vs SCE) which is noble than that of magnesium substrate. The zinc electroplating can be applied as the pretreatment process for electroless nickel plating on magnesium alloys.

  20. Application of microcontact printing to electroless plating for the fabrication of microscale silver patterns on glass.

    Science.gov (United States)

    Hsu, Chih-Hao; Yeh, Ming-Chih; Lo, Kung-Lung; Chen, Li-Jen

    2007-11-20

    Microcontact printing (microCP) and electroless plating are combined to produce microscale patterns of silver on glass substrates. Silver patterns with feature sizes of 0.6-10 microm stripes are fabricated using two methods. (1) The printing seeding layer (PSL) method is to apply microCP to directly print the catalyst Sn pattern for further electroless plating. (2) The printing masking layer (PML) method is to use microCP to print the octadecyltrichlorosilane (OTS) self-assembled monolayer as a masking layer on glass substrates, which then become Sn-activated in the unstamped regions by immersing the substrates in stannous chloride solution. After the electroless silver plating, the PML method has a better selectivity of silver deposition than the PSL method. In addition, variation of the deposited silver thickness as a function of the plating time and temperature is discussed. PMID:17944501

  1. Influence of surface treatment on the electroless nickel plating of textile fabric

    Science.gov (United States)

    Yuen, C. W. M.; Jiang, S. Q.; Kan, C. W.; Tung, W. S.

    2007-04-01

    The present study is performed with an objective to acquire a deeper understanding of the properties of nickel-plated polyester fabric after conducing low temperature plasma treatment. Low temperature plasma treatment with oxygen and argon gases was employed to render a hydrophilic property of woven polyester fabrics and facilitate the absorption of a palladium catalyst in order to provide a catalytic surface for electroless nickel plating. The properties of plasma-induced electroless nickel-plated polyester fabrics were evaluated by various standard testing methods in terms of both physical and chemical performances.

  2. Characterization Of Electroless Plating Of Co-Fe-P Films Key words: Electroless plating, Co-P-Fe, Plating properties

    International Nuclear Information System (INIS)

    Electroless deposition of Co-P bath containing FeSO4 as the source of Fe ions with good coverage onto copper as base metal were prepared to investigate their microstructure. Scanning electron microscopy and energy dispersive analysis were used to investigate the microstructure and chemical composition of the deposited coatings, respectively. The influence of FeSO4 addition on the deposition rate, chemical composition and the surface morphology of coatings were studied. The corrosion performance of the coated film was examined in 1 M HCl using weight loss technique. The results revealed that wt.% of Fe in deposit was increased with FeSO4 concentration while wt % of Co and P was reduced. Better corrosion resistance, fine grained deposited and lower deposition rate were observed by increasing Fe content into Co-P matrix

  3. Mechanical assisted electroless barrel-plating Ni-P coatings on magnesium alloy

    Institute of Scientific and Technical Information of China (English)

    Zhaoxia PING; Juntao YUAN; Yedong HE; Xiaogang LI

    2009-01-01

    A mechanically assisted electroless barrel-plating Ni-P was carried out in a rolling drum containing Mg alloy specimens and ceramic balls, which was submerged in a bath containing electroless plating solution. It is demonstrated that the Ni-P coatings deposited by this novel technique have a crystallized Ni-P solid solution structure,showing fine-grains, higher hardness, and higher corrosion resistance compared with the conventional electroless plated amorphous Ni-P coatings. After heat treatment at 400 ~C for 1 h, the structure of such Ni-P coatings were transformed to a structure with Ni-Ni3P double phases, and cracks in these coatings could not-be observed,whereas cracks appeared seriously in the conventional electroless plated Ni-P coating after same heat treatment. Therefore, both hardness and corrosion resistance of these Ni-P coatings can be improved further by heat treatment. All of these beneficial effects can be attributed to the role of mechanical attrition during the mechanically assisted electroless barrel-plating process.

  4. Effect of MWNT electroless Ag plating on field emission properties of MWNT/Ag nanocomposite cathodes

    Energy Technology Data Exchange (ETDEWEB)

    Ye Yun, E-mail: yeyun07@fzu.edu.cn [College of Physics and Information Engineering, Fuzhou University, Fuzhou 350002 (China); Guo Tailiang [College of Physics and Information Engineering, Fuzhou University, Fuzhou 350002 (China)

    2013-01-01

    Highlights: Black-Right-Pointing-Pointer Ag nanoparticles and coating were electroless plated onto the surface of CNTs. Black-Right-Pointing-Pointer A low turn on field of CNT/Ag cathode was achieved. Black-Right-Pointing-Pointer A new way for high stability of CNT/Ag cathode was suggested. - Abstract: Field emission properties of multiwall carbon nanotube (MWNT) electroless Ag plating nanocomposite cathodes fabricated using screen printing were studied. The MWNT was purified and electroless plated with Ag. The results of field emission scanning electron microscopy (FESEM) showed that the morphology of Ag electroless plating on the surface of MWNT depended on the temperature of electroless plating. Experiments showed that the stability of MWNT/Ag nanocomposite cathodes had no more than 10% degradation, achieving a field emission current density of 4.0 mA/cm{sup 2} at an applied electric field of 0.5 V/{mu}m for 50 h. The proposed MWNT/Ag nanocomposite cathodes possess good field emission properties and have potential for application in field emission displays.

  5. Effect of MWNT electroless Ag plating on field emission properties of MWNT/Ag nanocomposite cathodes

    International Nuclear Information System (INIS)

    Highlights: ► Ag nanoparticles and coating were electroless plated onto the surface of CNTs. ► A low turn on field of CNT/Ag cathode was achieved. ► A new way for high stability of CNT/Ag cathode was suggested. - Abstract: Field emission properties of multiwall carbon nanotube (MWNT) electroless Ag plating nanocomposite cathodes fabricated using screen printing were studied. The MWNT was purified and electroless plated with Ag. The results of field emission scanning electron microscopy (FESEM) showed that the morphology of Ag electroless plating on the surface of MWNT depended on the temperature of electroless plating. Experiments showed that the stability of MWNT/Ag nanocomposite cathodes had no more than 10% degradation, achieving a field emission current density of 4.0 mA/cm2 at an applied electric field of 0.5 V/μm for 50 h. The proposed MWNT/Ag nanocomposite cathodes possess good field emission properties and have potential for application in field emission displays.

  6. Enhanced microwave absorbing properties and heat resistance of carbonyl iron by electroless plating Co

    Science.gov (United States)

    Wang, Hongyu; Zhu, Dongmei; Zhou, Wancheng; Luo, Fa

    2015-11-01

    Co coated carbonyl iron particles (Co (CI)) are fabricated through electroless plating method, and the electromagnetic microwave absorbing properties are investigated in the frequencies during 8.2-12.4 GHz. The complex permittivity of CI particles after electroless plating Co is higher than that of raw CI particles due to improvment of the polarization process. Furthermore, according to the XRD and TG results, the Co layer can enhance the heat resistance of CI particles. The bandwidth below -10 dB can reach 3.9 GHz for the Co(CI) absorbent. The results indicate that the electroless plating Co not only enhances the absorbing properties but also improves the heat resistance of CI.

  7. Direct electroless Ni-P plating on AZ91D magnesium alloy

    Institute of Scientific and Technical Information of China (English)

    LI Zhong-hou; QU Yu-ping; ZHENG Feng; DAI A-gan

    2006-01-01

    An electroless Ni-P plating treatment was applied on AZ91D magnesium alloy to improve its corrosion resistance. Optimum pretreatment conditions and optimum bath of electroless nickel plating for magnesium alloy were found through many experiments. In order to avoid bother of pre-plating medium layer, a set of procedure of direct electroless Ni-P under the acid condition was investigated. The properties of the coating with 10% phosphorus were investigated. The results show that a coating with high hardness, low porosity and good adhesive strength is obtained. X-ray diffraction patterns show that the structure of the coating is an amorphous phase. After annealing at 400 ℃, the amorphous phase of Ni-P is transformed to crystalline phases,and some intermetallics as Ni3P and Ni5P2 are deposited from Ni -P solid solution along with an enhancing hardness from Hv 450 to Hv 910.

  8. ABS polymer electroless plating through a one-step poly(acrylic acid) covalent grafting.

    Science.gov (United States)

    Garcia, Alexandre; Berthelot, Thomas; Viel, Pascal; Mesnage, Alice; Jégou, Pascale; Nekelson, Fabien; Roussel, Sébastien; Palacin, Serge

    2010-04-01

    A new, efficient, palladium- and chromium-free process for the electroless plating of acrylonitrile-butadiene-styrene (ABS) polymers has been developed. The process is based on the ion-exchange properties of poly(acrylic acid) (PAA) chemically grafted onto ABS via a simple and one-step method that prevents using classical surface conditioning. Hence, ABS electroless plating can be obtained in three steps, namely: (i) the grafting of PAA onto ABS, (ii) the copper Cu(0) seeding of the ABS surface, and (iii) the nickel or copper metallization using commercial-like electroless plating bath. IR, XPS, and SEM were used to characterize each step of the process, and the Cu loading was quantified by atomic absorption spectroscopy. This process successfully compares with the commercial one based on chromic acid etching and palladium-based seed layer, because the final metallic layer showed excellent adhesion with the ABS substrate. PMID:20361751

  9. Regeneration and reuse of exhausted solutions of electroless nickel plating wood veneer

    Institute of Scientific and Technical Information of China (English)

    WANG Lijuan; LI Jian; LIAN Aizhen

    2006-01-01

    The regeneration of exhausted solutions of electroless nickel plating wood veneer was realized using soluble calcium salt to precipitate and remove phosphite and then using fluoride to remove residual calcium ions from the solution.The effect of the pH value of the solution,treatment temperature and the molar ratio of calcium ions to phosphite ions on the removal efficiency of phosphite was investigated.Wood veneer was electroless plated using regenerated solutions.A coating with better electrical conductivity and electromagnetic shielding was obtained.

  10. Electroless plating of honeycomb and pincushion polymer films prepared by self-organization.

    Science.gov (United States)

    Yabu, Hiroshi; Hirai, Yuji; Shimomura, Masatsugu

    2006-11-01

    This report describes the fabrication and electroless plating of regular porous and pincushion-like polymer structures prepared by self-organization. Honeycomb-patterned films were prepared by simple casting of polymer solution under applied humid air and pincushion structures by peeling off the top layer of the former films. Silver-deposited honeycomb-patterned films and pincushion films were obtained by simple electroless plating of the respective original structures. XPS revealed Ag deposition on the honeycomb-patterned film. After thermal decomposition or solvent elution of the template polymer, unique metal mesoscopic structures were obtained. PMID:17073508

  11. Excimer laser-induced formation of metallic microstructures by electroless copper plating

    Science.gov (United States)

    Yang, H.; Pan, C.-T.

    2002-03-01

    Micro-patterns created by the excimer laser and activated by reactants for electroless copper plating are described in this paper. The generated micro-patterns are transformed into copper patterns on the substrate and copper microstructures are formed. This method simplifies the manufacturing process of making circuits on boards compared with the conventional lithography process of forming copper patterns on the substrate. Micro-patterns generated by the excimer laser cause changes of surface electric properties and activation selectively. A chemical reaction through these activated areas may deposit metal, such as copper. The KrF excimer laser not only provides simple and fast machining patterns, but also uses its high-energy density to drill holes and circuits directly. Palladium ions are added as mediators in the electroless plating solution to enable a continuous electroless copper deposition. According to the experiment of excimer laser-assisted electroless copper plating, the procedures of pretreatment and post-cleaning are the key factors that resulted in excellent selective plating. The samples were pretreated by sodium dodecyl sulfate (SDS) and post-cleaned by acetone and diluted nitric acid resulting in distinct micro-patterns. The deposition area is confined to the excimer laser-ablated portion resulting in good selective plating.

  12. Enhanced microwave absorbing properties and heat resistance of carbonyl iron by electroless plating Co

    International Nuclear Information System (INIS)

    Co coated carbonyl iron particles (Co (CI)) are fabricated through electroless plating method, and the electromagnetic microwave absorbing properties are investigated in the frequencies during 8.2–12.4 GHz. The complex permittivity of CI particles after electroless plating Co is higher than that of raw CI particles due to improvment of the polarization process. Furthermore, according to the XRD and TG results, the Co layer can enhance the heat resistance of CI particles. The bandwidth below −10 dB can reach 3.9 GHz for the Co(CI) absorbent. The results indicate that the electroless plating Co not only enhances the absorbing properties but also improves the heat resistance of CI. - Highlights: • The Co-coated carbonyl iron Co(CI) particles were prepared by electroless plating. • The electromagnetic wave absorbing properties of Co(CI) particles were studied. • The heat treatment on the absorbing property of Co(CI) particles was studied. • The Co(CI) particles have good absorbing property when compared with CI

  13. Enhanced microwave absorbing properties and heat resistance of carbonyl iron by electroless plating Co

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Hongyu, E-mail: wanghongyu07010310@163.com; Zhu, Dongmei; Zhou, Wancheng; Luo, Fa

    2015-11-01

    Co coated carbonyl iron particles (Co (CI)) are fabricated through electroless plating method, and the electromagnetic microwave absorbing properties are investigated in the frequencies during 8.2–12.4 GHz. The complex permittivity of CI particles after electroless plating Co is higher than that of raw CI particles due to improvment of the polarization process. Furthermore, according to the XRD and TG results, the Co layer can enhance the heat resistance of CI particles. The bandwidth below −10 dB can reach 3.9 GHz for the Co(CI) absorbent. The results indicate that the electroless plating Co not only enhances the absorbing properties but also improves the heat resistance of CI. - Highlights: • The Co-coated carbonyl iron Co(CI) particles were prepared by electroless plating. • The electromagnetic wave absorbing properties of Co(CI) particles were studied. • The heat treatment on the absorbing property of Co(CI) particles was studied. • The Co(CI) particles have good absorbing property when compared with CI.

  14. Fabrication of porous flaky electromagnetic particles by electroless plating of CoNiP on diatomite

    Science.gov (United States)

    Yuan, Liming; Cai, Jun; Zhang, Wenqiang; Lian, Zhiyang; Zhang, Deyuan

    2012-10-01

    In order to fabricate lightweight flaky electromagnetic particles efficiently, the diatomite was used as the forming template to which the CoNiP coating was deposited by an electroless plating technique. The electroless plating of CoNiP on diatomite was accomplished with the coupling processing before the activation, in which 3-aminopropyltriethoxysilane (APTES) was used as the coupling agent. The effect of coupling processing on the activation and electroless plating of diatomite was characterized by SEM, FT-IR and EDS analysis. The results indicated that with coupling processing before activation, the catalytic effect was improved remarkably than that of direct colloidal palladium activation, which resulted in superior electroless plating on diatomite, even on the surface of submicron holes. The XRD analysis showed that the CoNiP coating was a transitional structure between crystal and amorphousness. The measurement of complex permeability and permittivity in the range of 2-18 GHz suggested that the micro flaky electromagnetic particles had promising electromagnetic properties.

  15. Electroless silver plating for metallization of near-field optical fiber probes

    Science.gov (United States)

    Li, Chang'an; Xu, Lina; Gu, Ning

    2007-10-01

    By using mercaptopropyltrimethoxysilane (MPTS) self-assembled monolayers (SAMs), electroless silver plating is developed for the metallization of near-field optical fiber probes. This method has the advantages of controllability, no pinholes, convenience, low cost, and smooth tip surface. The metallized probes are characterized by optical microscopy, scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDXS).

  16. The Studies of Composite Electroless Plating Process on Sintering Ndfeb Permanent Magnet

    Institute of Scientific and Technical Information of China (English)

    HUJian-wen; MAJing; YANDong-qing; GAOQing; MENGYong-qiang

    2004-01-01

    A reasonable pre-treatment and an ultrasonic pre-plating Cu film were applied for sintering NdFeB permanent magnet. The samples were then plated in neutral bath (PH=7) for 40rnin and in acidic bath (PH=4.8-5.1) for 2h. A composite electroless plating with different phosphor content was obtained. The results show that the composite plating coatings are dense and have a strong bond with the substrate, which contribute to the excellent corrosion resistance of the plating coating.

  17. The Studies of Composite Electroless Plating Process on Sintering Ndfeb Permanent Magnet

    Institute of Scientific and Technical Information of China (English)

    HU Jian-wen; MA Jing; YAN Dong-qing; GAO Qing; MENG Yong-qiang

    2004-01-01

    A reasonable pre-treatment and an ultrasonic pre-plating Cu film were applied for sintering NdFeB permanent magnet. The samples were then plated in neutral bath (PH=7) for 40min and in acidic bath (PH=4.8~5.1) for 2h. A composite electroless plating with different phosphor content was obtained. The results show that the composite plating coatings are dense and have a strong bond with the substrate, which contribute to the excellent corrosion resistance of the plating coating.

  18. Removal of platinum group metals from the used auto catalytic converter

    Directory of Open Access Journals (Sweden)

    A. Fornalczyk

    2009-04-01

    Full Text Available Recycling of platinum group metals from the used auto catalytic converters is profitable from ecological and also economical point of view. This work presents the analysis of the chances of removing the platinum group metals (PGM from the used auto catalytic converters applying pyrometallurgical and hydrometallurgical methods. The characteristics of auto catalytic converter is shown as well the available technologies used for processing the auto catalytic converters are also presented.

  19. Removal of platinum group metals from the used auto catalytic converter

    OpenAIRE

    A. Fornalczyk; M. Saternus

    2009-01-01

    Recycling of platinum group metals from the used auto catalytic converters is profitable from ecological and also economical point of view. This work presents the analysis of the chances of removing the platinum group metals (PGM) from the used auto catalytic converters applying pyrometallurgical and hydrometallurgical methods. The characteristics of auto catalytic converter is shown as well the available technologies used for processing the auto catalytic converters are also presented.

  20. Electroless silver plating on PET fabric initiated by in situ reduction of polyaniline

    Science.gov (United States)

    Mu, Shipeng; Xie, Huayang; Wang, Wei; Yu, Dan

    2015-10-01

    Novel electroless silver plating poly(ethylene terephthalate) (PET) fabric was prepared by a two-step procedure. In the first step, the in situ polymerized polyaniline (PANI) occurred on the fabric surface in the presence of ammonium persulfate (APS). Then, Ag(0) species reduced from silver nitrate (AgNO3) by in situ reduction of PANI were used as catalyst to initiate electroless silver plating. Hence, this composite material was prepared by conductive polymer combined with electroless plating. The silver layer on PET fabric surface was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy dispersive spectroscopy (EDX) as well as X-ray photoelectron spectroscopy (XPS). The results showed that the silver layer was plated uniformly and compactly with surface resistance about 0.1 Ω/sq on average. The shielding effectiveness (SE) of silver-plated PET fabric was around 50-90 dB, which was considered to have potential applications in electromagnetic shielding materials. Thermogravimetric (TG) analysis was carried out to study thermal stability. The antibacterial tests demonstrated that the silver-plated fabric exhibited excellent antibacterial activity against Staphylococcus aureus and Escherichia coli both with 100%.

  1. A Novel RF Inductor Fabricated Through MEMS Processing and Electroless Copper Plating

    Institute of Scientific and Technical Information of China (English)

    LIYi; WUWengang; HAOYilong

    2005-01-01

    A novel radio-frequency inductor with single-crystal-silicon spiral structure suspended on glass substrate is reported. The inductor is fabricated by using an improved silicon-glass anodic bonding and deep etching releasing process combined with electroless copper plating technology. The newly developed process is proved simple, stable and easily controlled. Based on the process, the performances of the inductor, such as quality factor, inductance and operating frequency, can be adjusted by changing the structure parameters. Through the electroless copper plating, the silicon spiral structure of the inductor is encapsulated completely by highly conformal copper film. Furthermore, a thin nickel film is plated on the top of the copper layer for passivation and measurement convenience. The thickness of copper and nickel layers influences the characteristics of the inductors largely. The fabricated inductor exhibits high performances. Its quality factor has reached 27 at the frequency arrange from 9 to 11GHz.

  2. Electroless plating and magnetic properties of Co–Zn–P coating on short carbon fibres

    Indian Academy of Sciences (India)

    Xinghua Su; Chengwen Qiang

    2012-12-01

    A layer of Co–Zn–P alloys was coated on short carbon fibre (CFs) surfaces using electroless plating method. The influence of the concentration of Co2+ and Zn2+ and reaction time on the plating rate were measured by comparing the relative mass gain rate of Co–Zn–P-coated fibres with uncoated carbon fibres prepared under different conditions. The materials characterizations were analysed by field emission scanning electron microscopy, X-ray diffraction and energy dispersive spectroscope. The magnetic properties of Co–Zn–P/CFs composites prepared in different Zn2+ concentration baths were measured by the vibrating sample magnetometer. The best processing parameters of electroless plating of Co–Zn–P coating on short carbon fibres were obtained.

  3. Metal deposition by electroless plating on polydopamine functionalized micro- and nanoparticles.

    Science.gov (United States)

    Mondin, Giovanni; Wisser, Florian M; Leifert, Annika; Mohamed-Noriega, Nasser; Grothe, Julia; Dörfler, Susanne; Kaskel, Stefan

    2013-12-01

    A novel approach for the fabrication of metal coated micro- and nanoparticles by functionalization with a thin polydopamine layer followed by electroless plating is reported. The particles are initially coated with polydopamine via self-polymerization. The resulting polydopamine coated particles have a surface rich in catechols and amino groups, resulting in a high affinity toward metal ions. Thus, they provide an effective platform for selective electroless metal deposition without further activation and sensitization steps. The combination of a polydopamine-based functionalization with electroless plating ensures a simple, scalable, and cost-effective metal coating strategy. Silver-plated tungsten carbide microparticles, copper-plated tungsten carbide microparticles, and copper-plated alumina nanoparticles were successfully fabricated, showing also the high versatility of the method, since the polymerization of dopamine leads to the formation of an adherent polydopamine layer on the surface of particles of any material and size. The metal coated particles produced with this process are particularly well suited for the production of metal matrix composites, since the metal coating increases the wettability of the particles by the metal, promoting their integration within the matrix. Such composite materials are used in a variety of applications including electrical contacts, components for the automotive industries, magnets, and electromagnetic interference shielding. PMID:24041548

  4. Electroless Plating of Carbon Nanotubes with Copper%碳纳米管的化学镀铜

    Institute of Scientific and Technical Information of China (English)

    凤仪; 袁海龙

    2004-01-01

    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, sensitization 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.

  5. Effect of electroless plating nickel treatment on electrode properties of Zr-based AB2 type alloy

    Institute of Scientific and Technical Information of China (English)

    文明芬; 翟玉春; 陈廉; 佟敏; 郑华; 马荣骏

    2001-01-01

    An electroless plating nickel treatment was processed to improve the active behaviors and discharge capacities of Zr-based AB2 alloys. The effects of the nickel coating on the surface appearance, the structure of the alloy powders and the electrode characteristics were investigated. It is found that the Ni-rich layer formed through electroless plating nickel treatment plays an important role on the initial activation property and the discharge capacity of Zr-based alloy. The optimal content of electroless plating nickel is about 15 %, and the discharge capacity of the electrode can be increased to 400mA· h·g 1 after 6 cycles. Although coated nickel is beneficial for quick activation and discharge capacity, excessive electroless plating nickel can result in a decreased discharge capacity.

  6. Development and Characterization of an Electroless Plated Silver/Cysteine Sensor Platform for the Electrochemical Determination of Aflatoxin B1

    OpenAIRE

    Alex Paul Wacoo; Mathew Ocheng; Deborah Wendiro; Peter California Vuzi; Joseph F. Hawumba

    2016-01-01

    An electroless plated silver/cysteine sensor platform [Glass|silver|cysteine|aflatoxin B1|horseradish peroxidase] for the Electrochemical detection of aflatoxin B1 was developed and characterized. This involved four major steps: (1) an electroless deposition of silver (plating) onto a glass slide, (2) immobilization of cysteine; (3) conjugation of aflatoxin B1 to cysteine groups; and (4) blocking of free cysteine groups with horseradish peroxidase (HRP). The binding of cysteine to the silver...

  7. Mechanism and Microstructure of Electroless Ni-Fe-P Plating on CNTs

    Institute of Scientific and Technical Information of China (English)

    XUE Ru-jun; WU Yu-cheng

    2007-01-01

    Electroless Ni-Fe-P alloy plating on the surface of CNTs was carried out with a bath using citrate salt and lactic acid as complex agents. We proposed a chemical reaction mechanism. The morphology, structure and chemical composition of the Ni-Fe-P/CNTs were studied with the aid of a scanning electronic microscope (SEM), X-ray diffraction (XRD) and an energy-dispersive X-ray spectral analysis (EDS). The results show that through a correct pretreatment and electroless plating, Ni-Fe-P/CNTs composite particles can be obtained. The optimum electroless plating parameters of 35-42 ℃ and pH of 8.5-9.7 were achieved. The as-plated Ni-Fe-P alloy is amorphous. After a heat treat-ment at 500 ℃ for 90 min in H2, the coating is transformed into crystalloid Ni3P, Fe2NiP and (Fe,Ni)3P. The Ni-Fe-P al-loy coating on the surface of CNTs is smooth and unique. The amount of Ni on the surface (mass fraction) of the Ni-Fe-P/CNTs composite particles is 29.13%, that of Fe 3.19% and that of P 2.28%.

  8. Nickel Electroless Plating: Adhesion Analysis for Mono-Type Crystalline Silicon Solar Cells.

    Science.gov (United States)

    Shin, Eun Gu; Rehman, Atteq ur; Lee, Sang Hee; Lee, Soo Hong

    2015-10-01

    The adhesion of the front electrodes to silicon substrate is the most important parameters to be optimized. Nickel silicide which is formed by sintering process using a silicon substrate improves the mechanical and electrical properties as well as act as diffusion barrier for copper. In this experiment p-type mono-crystalline czochralski (CZ) silicon wafers having resistivity of 1.5 Ω·cm were used to study one step and two step nickel electroless plating process. POCl3 diffusion process was performed to form the emitter with the sheet resistance of 70 ohm/sq. The Six, layer was set down as an antireflection coating (ARC) layer at emitter surface by plasma enhanced chemical vapor deposition (PECVD) process. Laser ablation process was used to open SiNx passivation layer locally for the formation of the front electrodes. Nickel was deposited by electroless plating process by one step and two step nickel electroless deposition process. The two step nickel plating was performed by applying a second nickel deposition step subsequent to the first sintering process. Furthermore, the adhesion analysis for both one step and two steps process was conducted using peel force tester (universal testing machine, H5KT) after depositing Cu contact by light induced plating (LIP). PMID:26726421

  9. Electroless nickel and ion-plated protective coatings for silvered glass mirrors

    Energy Technology Data Exchange (ETDEWEB)

    Lind, M.A.; Chaudiere, D.A.; Dake, L.S.; Stewart, T.L.

    1982-04-01

    A preliminary examination of two methods of protecting second surface silvered glass mirrors from environmental degradation is presented. One method employed silver mirrors overcoated with Al, Ni, 304 stainless steel, Cr, or an Al/Cu alloy prepared by ion-plating. The other method used conventional wet process silver mirrors protected with a thin electroless nickel coating. No attempt was made to optimize the coatings for either method. These experimental mirrors were compared with conventional paint backed silver/copper mirrors after exposure to elevated temperatures and water vapor in order to estimate their relative environmental stability. The electroless nickel mirrors showed consistently more resistance to these stresses than either the conventional or ion-plated mirrors, suggesting that they may provide more durable field service.

  10. Microwave-assisted activation for electroless nickel plating on PMMA microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yen-Chung [Graduate School of Defense Science, Chung Cheng Institute of Technology, National Defense University, Tao-Yuan, Taiwan 335 (China); Materials and Electro-optics Research Division, Chung Shan Institute of Science and Technology, Tao-Yuan, Taiwan 325 (China); Liu, Robert Lian-Huey [Graduate School of Defense Science, Chung Cheng Institute of Technology, National Defense University, Tao-Yuan, Taiwan 335 (China); Department of Chemical and Materials Engineering, Minghsin University of Science and Technology, Hsinchu Taiwan 304 (China); Chen, Xin-Liang [Graduate School of Defense Science, Chung Cheng Institute of Technology, National Defense University, Tao-Yuan, Taiwan 335 (China); Shu, Hsiou-Jeng [Materials and Electro-optics Research Division, Chung Shan Institute of Science and Technology, Tao-Yuan, Taiwan 325 (China); Ger, Ming-Der, E-mail: mingderger@gmail.com [Department of Chemical and Materials Engineering, Chung Cheng Institute of Technology, National Defense University, Tao-Yuan, Taiwan 335 (China)

    2011-05-15

    A novel microwave-assisted activation method for electroless plating on PMMA microspheres is presented in this study. When the microwave irradiation was applied during the activation step, the amount of the Pd species adsorbed on PMMA surfaces was much higher than that of sample pretreated with a conventional activation process without microwave irradiation. With this activation method, it was also shown that the adsorbed Pd species with a size of 4-6 nm were uniformly distributed on the surfaces of the PMMA microspheres, thus a smooth and uniform nickel-phosphorus coating on the PMMA microspheres was obtained by subsequent electroless plating. The samples after each step were characterized by XPS, TEM, ICP and SEM.

  11. A simple nickel activation process for electroless nickel-phosphorus plating on carbon fiber

    OpenAIRE

    Tingguo Yan; Leihong Li; Lijuan Wang

    2013-01-01

    A new nickel activation process was developed for metalizing the carbon fiber (CF) surface with electroless nickel plating. The oxidation and activation processes were examined using X-ray Photoelectron Spectroscopy (XPS), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectrometry (EDS), and X-ray Diffractometry (XRD). XPS analysis showed that HNO3 oxidation improved the O/C ratio of the CF surface, which resulted in an increase in the amount of oxygen-containing groups. As acti...

  12. Development of an Electromagnetic Wave Shielding Textile by Electroless Ni-Based Alloy Plating

    OpenAIRE

    Sonehara, Makoto; Noguchi, Shin; Kurashina, Tadashi; Sato, Toshiro; YAMASAWA, Kiyohito; Miura, Yoshimasa

    2009-01-01

    A polyester nonwoven textile with Ni-based alloy coating was fabricated, and the effect of electromagnetic wave shielding was evaluated. The Ni-based was coated by electroless plating on the textile. The electromagnetic wave shielding effect of the textile with Ni-B coating was about 99.98% over the induction range of 6-13 GHz. Because the textile has thin, light, flexible, and breathable characteristics, it will be versatile for the various electromagnetic wave shielding applications.

  13. Preparation of 103Pd brachytherapy seeds by electroless plating of 103Pd onto carbon bars

    International Nuclear Information System (INIS)

    A method for preparing 103Pd brachytherapy seeds is reported. The key of the method was to deposit 103Pd onto carbon bars by electroless plating so as to prepare source cores. After each carbon bar with 103Pd was sealed in a titanium capsule, the 103Pd seeds were fabricated. This paper provides valuable experiences and data for the preparation of 103Pd brachytherapy seeds

  14. High Aspect Pattern Formation by Integration of Micro Inkjetting and Electroless Plating

    OpenAIRE

    Gian, P.W.; Shan, Xuechuan; Liang, Y. N.; Lok, B.K.; Lu, C. W.; Ooi, B. L.

    2008-01-01

    This paper reports on formation of high aspect micro patterns on low temperature co-fired ceramic (LTCC) substrates by integrating micro inkjetting with electroless plating. Micro inkjetting was realized by using an inkjetting printer that ejects ink droplets from a printhead. This printhead consists of a glass nozzle with a diameter of 50 micrometers and a piezoelectric transducer that is coated on the nozzle. The silver colloidal solution was inkjetted on a sintered CT800 ceramic substrate,...

  15. Adhesion improvement of electroless copper plating on phenolic resin matrix composite through a tin-free sensitization process

    Science.gov (United States)

    Wang, Yong; Bian, Cheng; Jing, Xinli

    2013-04-01

    In order to improve the adhesion of electroless copper plating on phenolic resin matrix composite (PRMC), a new and efficient tin-free sensitization process has been developed. Electroless copper plating could be achieved in three steps, namely: (i) chemical etching with potassium permanganate solution; (ii) sensitization and activation with glucose and silver nitrate solution respectively; and (iii) electroless copper plating. Compared with the sample sensitized with stannous chloride (SnCl2), the copper plating obtained in the tin-free process showed excellent adhesion with the PRMC substrate, but had lower plating rate and conductivity. Additionally, the morphology of the copper plating was affected by the sensitization process, and the tin-free process was conducive to the formation of the large spherical copper polycrystal. Although the process is slightly complicated, the new sensitization process is so low-cost and environment-friendly that it is of great significance and could be applied into large-scale commercial manufacturing.

  16. Comparison Between Electrolysis and Reduction for Treatment of Spent Electroless Nickel Plating Bath

    Institute of Scientific and Technical Information of China (English)

    YAN Lei; LI Shuqin; YU Xiujuan

    2009-01-01

    There are lots of residual nickel and organic compounds in the spent electroless nickel plating bath. It not only wastes resource but also causes environmental pollution if the wastewater is discharged without treatment. In this paper, electrolytic method and reduction method for treating spent electroless nickel plating bath were compared. The factors studied included reaction time, pH, temperature, effectiveness and cost. It was found that the recovery rate of nickel by reduction was 99.9% under the condition ofpH 6, 50℃ for 10 min. The purity of reclaimed nickel was 66.1%. This treatment needed about 16 g NaBH4 for a liter spent solution, which cost RMB 64 Yuan. For electrolysis method, with pH 7.6, 80℃, 0.45 A (current intensity) for 2 h, the recovery rate reached 97.3%. The purity was 88.5% for the reclaimed nickel. Moreover, it was found that through electrolysis, the value of TOC (Total Organic Carbon) decreased from 114 to 3.08 g·L-1 with removal rate of 97.3%. The main cost of electrolysis came from electric energy. It cost about 0.09 kWh (less than RMB 0.1 Yuan) per liter wastewater. Compared with reduction, electrolysis had more advantages, so the priority of selection should be given to the electrolysis method for the treatment of spent electroless nickel plating bath.

  17. Study of electroless copper plating on ABS resin surface modified by heterocyclic organosilane self-assembled film

    Indian Academy of Sciences (India)

    H N Zhang; J Wang; F F Sun; D Liu; H Y Wang; F Wang

    2014-02-01

    6-(3-triethoxysilylpropyl)amino-1, 3, 5-triazine-2, 4-dithiol monosodium (TES) was used to fabricate self-assembled film on corona pretreated acrylonitrile–butadiene–styrene (ABS) resin surface. The self-assembled film modified ABS resin was treated by electroless copper plating. Orthogonal test was carried out to study optimal condition of the process. The surface appearance, plating rate and thickness of electroless copper films were investigated to determine the optimal time of corona-discharge, self-assembly and electroless copper plating. SEM results indicated that porous morphology appeared on ABS resin surface modified by TES self-assembled film and the surface roughness also increased. The adhesion test showed that the adhesion property between ABS resin and copper was excellent. The surface of electroless copper film had high brightness under the optimal condition of 1 min corona-discharge, 30 min self-assembly and 10 min electroless copper plating. The electroless-copper plating temperature was 55 ∼ 60°C and pH was 13 ∼ 13.5.

  18. Electroless silver plating of the surface of organic semiconductors.

    Science.gov (United States)

    Campione, Marcello; Parravicini, Matteo; Moret, Massimo; Papagni, Antonio; Schröter, Bernd; Fritz, Torsten

    2011-10-01

    The integration of nanoscale processes and devices demands fabrication routes involving rapid, cost-effective steps, preferably carried out under ambient conditions. The realization of the metal/organic semiconductor interface is one of the most demanding steps of device fabrication, since it requires mechanical and/or thermal treatments which increment costs and are often harmful in respect to the active layer. Here, we provide a microscopic analysis of a room temperature, electroless process aimed at the deposition of a nanostructured metallic silver layer with controlled coverage atop the surface of single crystals and thin films of organic semiconductors. This process relies on the reaction of aqueous AgF solutions with the nonwettable crystalline surface of donor-type organic semiconductors. It is observed that the formation of a uniform layer of silver nanoparticles can be accomplished within 20 min contact time. The electrical characterization of two-terminal devices performed before and after the aforementioned treatment shows that the metal deposition process is associated with a redox reaction causing the p-doping of the semiconductor. PMID:21875110

  19. Direct writing patterns for electroless plated copper thin film on plastic substrates.

    Science.gov (United States)

    Liao, Ying-Chih; Kao, Zhen-Kai

    2012-10-24

    A simple and efficient method is developed to create conductive copper thin films on polymer surfaces. Instead of regular palladium colloid inks, micropatterns of silver nitrate inks, which serve as an activating agent for copper plating, were printed and dried on flexible plastic substrates. The printed plastic sheets were then immersed in an electroless copper plating bath at 55 °C for 2 min to create copper thin films on the printed patterns. The prepared copper films have an electrical conductivity as high as 83% of bulk copper and show good adhesion on PET or PI substrates. PMID:22989044

  20. The electrochemical recovery of metallic palladium from spent electroless plating solution

    Science.gov (United States)

    Warner, Nathan; Free, Michael L.

    2009-10-01

    Semiconductor bond pads are sometimes coated with palladium for good electrical properties and wire adhesion. The palladium is deposited by immersing the wafers in an electroless plating solution. When the plating solution is depleted and no longer achieves the desired results it is treated as waste. This work investigates the recovery of the remaining palladium in the waste solution by means of electrochemical deposition onto a high surface area cathode. Experiments show that the remaining palladium can be recovered economically and efficiently. This makes the process environmentally friendly and cost effective.

  1. Polycarbonate activation for electroless plating by dimethylaminoborane absorption and subsequent nanoparticle deposition

    Science.gov (United States)

    Muench, Falk; Bohn, Sebastian; Rauber, Markus; Seidl, Tim; Radetinac, Aldin; Kunz, Ulrike; Lauterbach, Stefan; Kleebe, Hans-Joachim; Trautmann, Christina; Ensinger, Wolfgang

    2014-07-01

    Electroless plating of metal films on polymer substrates usually requires the presence of metal particles acting as catalytically active nuclei for the deposition reaction. Herein, we present a novel and versatile approach towards the activation of polycarbonate substrates with metal nanoparticles. It is based on the diffusion of dimethylaminoborane into the polymer matrix, followed by reaction of the sensitized substrates with metal salt solutions. The reducing agent uptake was controlled by changing the duration of the sensitization and the dimethylaminoborane concentration in the sensitization solution. Different seed types (Ag, Au, Pd, Pt and Rh) were deposited by variation of the activation solution. The proposed mechanism was confirmed with FTIR and TEM measurements. In addition, AFM revealed that apart from a slight roughening in the nanometer range, the surface morphology of the polymer remained unchanged, rendering the method viable for template-based nanomaterial fabrication. Due to its pronounced variability, the new technique allows to tailor the activity of polymer substrates for consecutive electroless plating. The feasibility and nanoscale homogeneity of the process were proven by the electroless fabrication of well-defined Au and Pt nanotubes in ion-track etched polycarbonate templates. The combination of features (use of simple and easily scalable wet-chemical processes, facile seed variation, high activation quality on complex surfaces) renders the outlined technique promising for the fabrication of intricate nanomaterials as well as for the metallization of macroscopic work pieces.

  2. Fabrication of electroless nickel plated aluminum freeform mirror for an infrared off-axis telescope.

    Science.gov (United States)

    Kim, Sanghyuk; Chang, Seunghyuk; Pak, Soojong; Lee, Kwang Jo; Jeong, Byeongjoon; Lee, Gil-Jae; Kim, Geon Hee; Shin, Sang Kyo; Yoo, Song Min

    2015-12-01

    Freeform mirrors can be readily fabricated by a single point diamond turning (SPDT) machine. However, this machining process often leaves mid-frequency errors (MFEs) that generate undesirable diffraction effects and stray light. In this work, we propose a novel thin electroless nickel plating procedure to remove MFE on freeform surfaces. The proposed procedure has a distinct advantage over a typical thick plating method in that the machining process can be endlessly repeated until the designed mirror surface is obtained. This is of great importance because the sophisticated surface of a freeform mirror cannot be optimized by a typical SPDT machining process, which can be repeated only several times before the limited thickness of the nickel plating is consumed. We will also describe the baking process of a plated mirror to improve the hardness of the mirror surface, which is crucial for minimizing the degradation of that mirror surface that occurs during the polishing process. During the whole proposed process, the changes in surface figures and textures are monitored and cross checked by two different types of measurements, as well as by an interference pattern test. The experimental results indicate that the proposed thin electroless nickel plating procedure is very simple but powerful for removing MFEs on freeform mirror surfaces. PMID:26836671

  3. Microwave absorbing properties of Ag-coated Ni-Zn ferrite microspheres prepared by electroless plating

    International Nuclear Information System (INIS)

    Research highlights: → Microwave absorptive composition comprising Ag-coated Ni-Zn ferrite microspheres. → A conductive Ag layer was coated on the ferrite spheres by electroless plating. → The ferrite-rubber composites exhibit high dielectric constant and dielectric loss. → A reduced matching thickness is predicted with the conductive ferrite microspheres. - Abstract: This investigation presents an electromagnetic radiation absorptive composition comprising Ag-coated ferrite microspheres dispersed in a silicone rubber matrix for use as a thin microwave absorber in GHz frequencies. Ni-Zn ferrite microspheres with an average diameter of 50 μm were prepared by spray-drying and sintering at 1130 oC. A conductive Ag layer was coated on the ferrite spheres by electroless plating. Uniform Ag coating can be obtained using the plating solution with a high AgNO3 concentration. For particle compacts of the conductive Ni-Zn ferrite spheres, electrical resistance is reduced to as low as 10-2 Ω. Rubber composites containing the Ag-plated ferrite spheres exhibit a high value of both real and imaginary parts of complex permittivity, while the complex permeability spectrum is not significantly changed with Ag plating. Due to the conductive and magnetic property of the microspheres, matching thickness can be reduced to as low as 2 mm at the frequency of 7.6 GHz, which is much thinner than non-coated ferrite absorbers.

  4. Microwave absorbing properties of Ag-coated Ni-Zn ferrite microspheres prepared by electroless plating

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jong-Hyuk [Department of Advanced Materials Engineering, Chungbuk National University, Cheongju 361-763 (Korea, Republic of); Kim, Sung-Soo, E-mail: sskim@chungbuk.ac.kr [Department of Advanced Materials Engineering, Chungbuk National University, Cheongju 361-763 (Korea, Republic of)

    2011-03-24

    Research highlights: > Microwave absorptive composition comprising Ag-coated Ni-Zn ferrite microspheres. > A conductive Ag layer was coated on the ferrite spheres by electroless plating. > The ferrite-rubber composites exhibit high dielectric constant and dielectric loss. > A reduced matching thickness is predicted with the conductive ferrite microspheres. - Abstract: This investigation presents an electromagnetic radiation absorptive composition comprising Ag-coated ferrite microspheres dispersed in a silicone rubber matrix for use as a thin microwave absorber in GHz frequencies. Ni-Zn ferrite microspheres with an average diameter of 50 {mu}m were prepared by spray-drying and sintering at 1130 {sup o}C. A conductive Ag layer was coated on the ferrite spheres by electroless plating. Uniform Ag coating can be obtained using the plating solution with a high AgNO{sub 3} concentration. For particle compacts of the conductive Ni-Zn ferrite spheres, electrical resistance is reduced to as low as 10{sup -2} {Omega}. Rubber composites containing the Ag-plated ferrite spheres exhibit a high value of both real and imaginary parts of complex permittivity, while the complex permeability spectrum is not significantly changed with Ag plating. Due to the conductive and magnetic property of the microspheres, matching thickness can be reduced to as low as 2 mm at the frequency of 7.6 GHz, which is much thinner than non-coated ferrite absorbers.

  5. Preparation and characterization of molybdenum powders with copper coating by the electroless plating technique

    Institute of Scientific and Technical Information of China (English)

    WANG Guangjun; WANG Dezhi

    2008-01-01

    Molybdenum powders with a diameter of approximately 3 μm were coated with copper using the electroless plating technique in the pH 12.5-13 and temperature range of 55-75℃.The optimization of the electroless copper bath was evaluated through the combination of process parameters like pH and temperature.The optimized values of pH and temperature were found to be 12.5 and 60℃,respectively,which attributes to the bright maroon color of the coating with an increase in weight of 46%.The uncoated and coated powders were subjected to microstructural studies using scanning electron microscope (SEM) and the phases were analyzed using X-ray diffraction (XRD).An attempt was made to understand the growth mechanism of the coating.The diffusion-shrinkage autocatalytic model was suggested for copper growth on the molybdenum surface.

  6. Improvement of copper plating adhesion on silane modified PET film by ultrasonic-assisted electroless deposition

    International Nuclear Information System (INIS)

    Copper thin film on silane modified poly(ethylene terephthalate) (PET) substrate was fabricated by ultrasonic-assisted electroless deposition. The composition and topography of copper plating PET films were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and atomic force microscopy (AFM), respectively. Peel adhesion strength, as high as 16.7 N/cm, was achieved for the planting copper layer to the modified PET substrate with ultrasonic-assisted deposition; however, a relative low value as 11.9 N/cm was obtained for the sample without ultrasonic vibration by the same measurement. The electrical conductivity of Cu film was changed from 7.9 x 104 to 2.1 x 105 S/cm by using ultrasonic technique. Ultrasonic operation has the significant merits of fast deposition and formation of good membranes for electroless deposition of Cu on PET film.

  7. Site-selective electroless nickel plating on patterned thin films of macromolecular metal complexes.

    Science.gov (United States)

    Kimura, Mutsumi; Yamagiwa, Hiroki; Asakawa, Daisuke; Noguchi, Makoto; Kurashina, Tadashi; Fukawa, Tadashi; Shirai, Hirofusa

    2010-12-01

    We demonstrate a simple route to depositing nickel layer patterns using photocross-linked polymer thin films containing palladium catalysts, which can be used as adhesive interlayers for fabrication of nickel patterns on glass and plastic substrates. Electroless nickel patterns can be obtained in three steps: (i) the pattern formation of partially quaterized poly(vinyl pyridine) by UV irradiation, (ii) the formation of macromolecular metal complex with palladium, and (iii) the nickel metallization using electroless plating bath. Metallization is site-selective and allows for a high resolution. And the resulting nickel layered structure shows good adhesion with glass and plastic substrates. The direct patterning of metallic layers onto insulating substrates indicates a great potential for fabricating micro/nano devices. PMID:21069972

  8. Preparation and magnetic properties of Ni-P-La coating by electroless plating on silicon substrate

    Science.gov (United States)

    Gao, Yun; Wang, Jihui; Yuan, Jing; Li, Haiqin

    2016-02-01

    Ni-P-La coatings were prepared on Si substrate by electroless plating method under different La content, pH value, plating temperature and plating time. The surface morphology, chemical composition, structure and magnetic properties of coatings were observed and determined by scanning electron microscope (SEM), energy dispersive X-ray spectrometry (EDS), X-ray diffractometer (XRD) and vibrating sample magnetometer (VSM). The results showed that Ni-P-La coating is smooth and uniform with a cellular morphology grown in columnar manner. With the increase of La content, pH value and plating time, the thickness and saturation magnetization of coating are increased continuously, but the stability of plating bath is decreased greatly with La content and pH value. Under higher plating temperature, the thickness and saturation magnetization of coatings are obviously enhanced. But too high plating temperature is harmful to the plating bath and coating. The optimum plating conditions for Ni-P-La coating is La2O3 addition of 10 mg L-1, pH value of 5.0, plating temperature of 75 °C and plating time of 45 min. The role of La element is to benefit the deposition of Ni element, promote the formation of Ni phase during the annealing process, and thus improve the magnetic properties of Ni-P-La coating.

  9. A New Activation Method for Electroless Metal Plating: Palladium Laden via Bonding with Self-Assembly Monolayers

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A new activation method has been developed for electroless copper plating on silicon wafer based on palladium chemisorption on SAMs of APTS without SnCl2 sensitization and roughening condition. A closely packed electroless copper film with strong adhesion is successfully fonned by AFM observation. XPS study indicates that palladium chemisorption occurred via palladium chloride bonding to the pendant amino group of the SAMs.

  10. Direct Electroless Nickel Plating on AZ91D Magnesium Alloy from a Sulfate Solution and its Deposition Mechanism

    Institute of Scientific and Technical Information of China (English)

    GUChang-dong; LIANJian-she; LIGuang-yu; NIULi-yuan; JIANGZhong-hao

    2004-01-01

    A bath of electroless plating Ni on the AZ91D magnesium alloy, containing sulfate nickel, was given in this paper. The nucleation mechanism of Ni-P deposits on the AZ91D magnesium alloy was studied by using XRD and SEM. The electroless Ni-P deposits were preferentially nucleated on the β(Mg17Al12) phase and extended to the primary and eutectic α phases of the AZ91D magnesium alloy.

  11. Electrochemical behavior of Cu-Zn-Al shape memory alloy after surface modification by electroless plated Ni-P

    Institute of Scientific and Technical Information of China (English)

    LIANG Chenghao; CHEN Bangyi; CHEN Wan; WANG Hua

    2004-01-01

    The electrochemical behavior of Cu-Zn-Al shape memory alloy (SMA) with and without electroless plated Ni-P was investigated by electrochemical methods in artificial Tyrode's solution. The results showed that Cu-Zn-Al SMA engendered dezincification corrosion in Tyrode's solution. The anodic active current densities as well as electrochemical dissolution sensitivity of the electroless plated Ni-P Cu-Zn-Al SMA increased with NaCl concentration rising, pH of solution decreasing and environmental temperature uprising. X-ray diffraction analysis indicated that after surface modification by electroless plated Ni-P, an amorphous plated film formed on the surface of Cu-Zn-Al SMA. This film can effectively isolate matrix metal from corrosion media and significantly improve the electrochemical property of Cu-Zn-Al SMA in artificial Tyrode's solution.

  12. Factors Affecting the Morphology of Pb-Based Glass Frit Coated with Ag Material Prepared by Electroless Silver Plating

    Science.gov (United States)

    Huang, Bei; Gan, Weiping; Zhou, Jian; Li, Yingfen; Lin, Tao; Liu, Xiaogang

    2014-05-01

    Pb-based glass frit coated with nanosilver material for Si solar cell applications has been directly prepared by electroless silver plating. Activation of the glass frit was accomplished by using glycol, with the aim of reducing the silver ions to elemental silver on the surface of the glass frit. Electroless silver plating onto the glass frit was successfully realized using two kinds of electroless plating bath. However, the morphology of the composite powder greatly affected the modality, sheet resistance, series resistance, and photoelectric conversion efficiency of the conducting silver films. We found that the activation temperature affected the number and distribution of silver nanoparticles. Meanwhile, the average grain size of the silver particles and the silver content in the Pb-based glass frit coated with Ag material could be controlled by adjusting the pH value and loading capacity, respectively, during plating.

  13. An electroless plating film of palladium on 304 stainless steel and its excellent corrosion resistance

    International Nuclear Information System (INIS)

    An uniform palladium film on 304 stainless steel was obtained by electroless plating. Scanning electronic microscopy, X-ray photoelectron spectroscopy, weight loss tests and electrochemical measurements were used to character the properties of the film. The palladium plated stainless steel samples showed excellent corrosion resistance in strong reductive corrosion mediums. In boiling dilute sulfuric acid solutions and boiling acetic/formic acids, corrosion rates of palladium plated 304 stainless steel samples were 3 or 4 orders of magnitude lower than the original 304 stainless steel samples. In solutions with NaCl concentration less that 0.1%, the palladium plated samples also showed better corrosion resistance. The function of palladium film on stainless steel is to raise the electrode potential and promote passivation of the steel in strong corrosive environments

  14. Electroless nickel plating of arc discharge synthesized carbon nanotubes for metal matrix composites

    Energy Technology Data Exchange (ETDEWEB)

    Jagannatham, M.; Sankaran, S.; Prathap, Haridoss, E-mail: prathap@iitm.ac.in

    2015-01-01

    Highlights: • Electroless Ni coatings have been performed on CNTs for various deposition times. • The deposition of nickel increased with increase in deposition time. • A deposition time of 60 min has been optimum for uniform coating of Ni on CNTs. • The CNTs with uniform coating of Ni are potential for reinforcements in composites. • Electroless nickel coatings are determined to be super paramagnetic behavior. - Abstract: Electroless nickel (EN) plating was performed on arc discharge synthesized multiwalled carbon nanotubes for various deposition times. X-ray diffraction (XRD), Transmission electron microscopy (TEM), and Raman spectroscopy characterization techniques are used to identify the presence of nickel deposition on the carbon nanotubes (CNTs) and the degree of graphitization. The results indicate that impurities are less in the purified CNTs as compared to raw carbon soot. Increasing deposition time up to 60 min increases uniform deposition of nickel throughout the length of the CNTs. However, for deposition time longer than 60 min, nickel particles are seen separated from the surface of the CNTs. Uniformly coated nickel CNTs throughout their length are potential candidates for reinforcements in composite materials. Magnetic properties of the nickel coated CNTs, with deposition time of 30 and 60 min were also evaluated. The magnetic saturation of nickel coated CNTs with deposition time of 30 min is less compared to nickel coated CNTs with deposition time of 60 min.

  15. Study of electroless nickel plating on PerFactoryTM rapid prototype model

    OpenAIRE

    J.C. Rajaguru; C. Au, M. Duke

    2012-01-01

    This paper presents an investigation of electroless nickel plating on PerFactoryTM rapid prototype model built on PerFactoryTM R05 material. PerFactoryTM R05 is acrylic based photo sensitive resin. It is a popular material in rapid prototyping using PerFactoryTM method which employs addictive manufacturing technique to build prototypes for visual inspection, assembly etc. Metallization of such a prototype can extend the application envelop of the rapid prototyping technique as they can be use...

  16. Electroless nickel plating on patterned catalytic surfaces by electron beam lithography

    International Nuclear Information System (INIS)

    Nickel-phosphorus (Ni-P) alloy thin films with high-resolution features were created on patterned palladium (Pd) catalytic surfaces by electroless plating. Pd catalyst underlayers were patterned by incorporating Pd nanoparticles with site selectivity into poly(methyl methacrylate) thin films by combining electron beam lithography and the reduction of palladium(II) bis(acetylacetonato) used as a precursor. The quality of the metallic surface patterns was evaluated in terms of the attainable pattern sizes and the deviation from the pre-designed patterns. Dense Ni-P lines with the width of about 150 nm could be obtained with good site selectivity

  17. ELECTROLESS COPPER PLATING ON FRAXINUS MANDSHURICA VENEER USING GLYOXYLIC ACID AS REDUCING AGENT

    OpenAIRE

    Lijuan Wang; Lili Sun; Jian Li

    2011-01-01

    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...

  18. Selective silver seeding on laser modified polyimide for electroless copper plating

    International Nuclear Information System (INIS)

    Copper was selectively deposited on PI surface catalyzed by laser-induced deposition of Ag particles. First, PI film was ablated by a focused Nd:YAG laser (λ = 266 nm) for patterning, and then the ablated film was immersed in a silver diammine solution. Ag(NH3)2+ ions were reduced to Ag at the ablated region on the film, and the Ag particles were deposited in situ. After rinsing the film, copper was deposited on the seeded film by electroless plating successfully. Deposits and the ablated film were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and Stylus Profiler

  19. High Aspect Pattern Formation by Integration of Micro Inkjetting and Electroless Plating

    CERN Document Server

    Gian, P W; Liang, Y N; Lok, B K; Lu, C W; Ooi, B L

    2008-01-01

    This paper reports on formation of high aspect micro patterns on low temperature co-fired ceramic (LTCC) substrates by integrating micro inkjetting with electroless plating. Micro inkjetting was realized by using an inkjetting printer that ejects ink droplets from a printhead. This printhead consists of a glass nozzle with a diameter of 50 micrometers and a piezoelectric transducer that is coated on the nozzle. The silver colloidal solution was inkjetted on a sintered CT800 ceramic substrate, followed by curing at 200 degrees C for 60 minutes. As a result, the silver trace with a thickness of 200 nm was obtained. The substrate, with the ejected silver thin film as the seed layer, was then immersed into a preinitiator solution to coat a layer of palladium for enhancing the deposition of nickel. Electroless nickel plating was successfully conducted at a rate of 0.39 micrometers /min, and the thickness of traces was plated up to 84 micrometers. This study demonstrates that the integration of inkjetting with plat...

  20. Environmentally friendly electroless plating for Ag/TiO2-coated core-shell magnetic particles using ultrasonic treatment.

    Science.gov (United States)

    Kim, Soo-Dong; Choe, Won-Gyun; Jeong, Jong-Ryul

    2013-11-01

    In this work, high-reflectance brilliant white color magnetic microspheres comprising a Fe/TiO2/Ag core-shell structure with a continuous, uniform compact silver layer were successfully fabricated by TiO2-assisted electroless plating in a simple and eco-friendly method. The coating procedure for TiO2 and Ag involved a sol-gel reaction and electroless plating with ultrasound treatment. The electroless plating step was carried out in an eco-friendly manner in a single process without environmentally toxic additives. The TiO2 layer was used as a modification layer between the Fe microspheres and the silver layer to improve adhesion. A continuous and compact silver layer could be formed with a high degree of morphological control by introducing ultrasonication and adjusting the ammonium hydroxide concentration. PMID:23611665

  1. Effect of hydrogen plasma on electroless-plating Ni-B films and its Cu diffusion barrier property.

    Science.gov (United States)

    Choi, Kyeong-Keun; Kee, Jong; Kwon, Da-Jung; Kim, Deok-Kee

    2014-12-01

    Electroless-plating Ni-B films have been evaluated for the application as the diffusion barrier and metal cap for copper integration. The effect of post plasma treatment in a hydrogen environment on the characteristics of Ni-B films such as chemical composition, surface roughness, crystallinity, and resistivity was investigated. By treating electroless-plating Ni-B films with H2 plasma, the resistance and the roughness of the films decreased. The leakage current of Ni-B bottom electrode/30-nm-thick Al2O3/Al top electrode structures improved after the H2 plasma treatment on the Ni-B films. 40 nm-thick electroless-plating Ni-B film was able to block Cu diffusion up to 350 degrees C. PMID:25971105

  2. Electroless plating Ni-P matrix composite coating reinforced by carbon nanotubes

    Institute of Scientific and Technical Information of China (English)

    邓福铭; 陈小华; 陈卫祥; 李文铸

    2004-01-01

    Ni-P matrix composite coating reinforced by carbon nanotubes (CNTs) was deposited by electroless plating. The most important factors that influence the content of carbon nanotubes in deposits, such as agitation, surfactant and carbon nanotubes concentration in the plating bath were investigated. The surface morphology, structure and properties of the Ni-P-CNTs coating were examined. It is found that the maximum content of carbon nanotubes in the deposits is independent of carbon nanotubes concentration in the plating bath when it is up to 5 mg/L. The test results show that the carbon nanotubes co-deposited do not change the structure of the Ni-P matrix of the composite coating, but greatly increase the hardness and wear resistance and decrease the friction coefficient of the Ni-PCNTs composite coating with increasing content of carbon nanotubes in deposits.

  3. A novel process of electroless Ni-P plating with plasma electrolytic oxidation pretreatment

    Science.gov (United States)

    Liu, Zhenmin; Gao, Wei

    2006-12-01

    A novel Ni based coating - plasma electrolytic oxidation (PEO) pre-treatment followed by electroless nickel (EN) plating - has been developed to produce pore free Ni coatings on AZ91 magnesium alloy. The application of the PEO film between the nickel coating and the substrate acts as an effective barrier and catalytic layer for the subsequent nickel plating. The potentiodynamic tests indicated that the corrosion current density of the PEO + EN plating on AZ91 decreased by almost two orders of magnitudes compared to the traditional EN coating. Salt fog spray testing further proved this improvement. More importantly, the new technique does not use Cr +6 and HF in its pretreatment, therefore is a much environmentally friendlier process.

  4. Characterization of nano-sized SiC@Ni composite fabricated by electroless plating method.

    Science.gov (United States)

    Xu, Zhan; Chen, Yigang

    2013-02-01

    A nano-sized SiC@Ni composite was prepared by simple electroless plating method. Nickel can be reduced by Na2H2PO2 under the catalysis of Pd to despite onto the surface of SiC nanoparticles. The composite structure was characterized by means of TEM images, XRD and the components were analyzed using EDS. The coating layer on the SiC particles was several nanometers thick and mainly in a form of fine Ni crystalline grain and amorphous Ni-P alloy. By increasing the concentration of Na2H2PO2 in the plating bath, the uniformity of the coating layer can be improved obviously. Both of the magnetism and crystallinity of Ni coatings depends on the P content in the coating which can be decreased by increasing the pH values of plating solutions. The SiC@Ni particles exhibited soft magnetic characteristics. PMID:23646660

  5. Preparation of conductive silk fabric with antibacterial properties by electroless silver plating

    Science.gov (United States)

    Yu, Dan; Kang, Gengen; Tian, Weicheng; Lin, Lu; Wang, Wei

    2015-12-01

    To obtain an efficient approach to metalize silk fabric, a novel method was explored and silver-plated silk was prepared. In this study, tris (2-carboxyethyl) phosphine (TCEP) was utilized as a reducing agent to generate thiol groups on the silk surface. These thiol groups react with silver ions to form metal complexes, which were used as catalytic seeds and successfully initiated electroless silver plating. A variety of methods, including Raman, XRD, TG, SEM and EDS were used to characterize the intermediates and final products. The results showed that a uniform and smooth metal layer could be obtained when compared with that without TCEP pretreatment. The silver-plated silk fabric exhibited good electrical conductivity and high anti-bacterial properties. These attractive features enable this conductive silk fabric to be a good candidate as a biomedical material.

  6. THE ELECTROCHEMICAL PROPERTIES OF Li/FeS BATTERY USING ELECTROLESS NICKEL PLATED FeS POWDER

    OpenAIRE

    SUNG-HYUN KIM; YOUNG-JIN CHOI; DONG-HUN KIM; SUNG-HOON JUNG; KI-WON KIM; HYO-JUN AHN; JOU-HYEON AHN; HAL-BON GU

    2008-01-01

    In order to investigate the electrochemical properties of Li/FeS cell, FeS powder was fabricated by using a high-energy ball milling method. Then, surface of FeS powder was coated with metallic nickel. Nickel coating was conducted by using electroless nickel plating method. Nickel chloride (NiCl2 · 6H2O) was used as the nickel ion source for electroless nickel plating. The effects of nickel coating on the electrochemical properties of FeS electrode for Li/FeS cell were investigated by CV meas...

  7. Control of biofouling on titanium condenser tubes with the use of electroless copper plating

    International Nuclear Information System (INIS)

    In sea water environments titanium condenser tubes face serious issues of biofouling and biomineralization. Electroless plating of nanocopper film is attempted inside the tubes for the control of biofilm formation. Using advanced techniques like AFM, SEM, and XPS, electroless copper plated flat Ti specimens were characterized. Examination of Cu coated Ti surfaces using AFM and SEM showed more reduction in the microroughness compared to anodized Ti surface. Cu 2p3/2 peak in XPS spectral analysis showed the shift in binding energy inferring the reduction of the hydroxide to metallic copper. Tubular specimens were exposed to sea water up to three months and withdrawn at monthly intervals to evaluate antibacterial activity and long term stability of the coating. Total viable counts and epifluorescence microscopy analyses showed two orders decrease in bacterial counts on copper coated Ti specimens when compared to as polished control Ti specimens. Molecular biology techniques like DGGE and protein expression analysis system were done to get insight into the community diversity and copper tolerance of microorganisms. DGGE gel bands clearly showed the difference in the bacterial diversity inferring from the 16S rRNA gene fragments (V3 regions). Protein analysis showed distinct protein spots appearing in electroless copper coated Ti biofilm protein samples in addition to protein spots common to both the biofilms of Cu coated and as polished Ti. The results indicated copper accumulating proteins in copper resistant bacterial species of biofilm. Reduced microroughness of the surface and toxic copper ions resulted in good biofouling control even after three months exposure to sea water. (author)

  8. A simple nickel activation process for electroless nickel-phosphorus plating on carbon fiber

    Directory of Open Access Journals (Sweden)

    Tingguo Yan

    2013-02-01

    Full Text Available A new nickel activation process was developed for metalizing the carbon fiber (CF surface with electroless nickel plating. The oxidation and activation processes were examined using X-ray Photoelectron Spectroscopy (XPS, Scanning Electron Microscopy (SEM, Energy Dispersive X-ray Spectrometry (EDS, and X-ray Diffractometry (XRD. XPS analysis showed that HNO3 oxidation improved the O/C ratio of the CF surface, which resulted in an increase in the amount of oxygen-containing groups. As activation time increased, both Nio cluster and Ni-P deposits increased. More than 50 mg of Nio clusters formed on the surface of 1g CF. SEM observations illustrated that particles and island-like shapes were developed from the Nio cluster, which helped to initiate the electroless nickel-plating on the CF surface. A continuous and compact coating with a thickness of about 2 to 3 μm was obtained. EDS results showed that the nickel and phosphorus content in the deposits was 97.34 wt.% and 2.66 wt.%, respectively. XRD indicated that the Ni-P coating was crystalline and the maximum deposition on 1 g CFs was as high as 9000 mg. As the results of the observations reveal, the activation method is a feasible alternative to Pd activation.

  9. A novel process of electroless Ni-P plating by nonisothermal method

    International Nuclear Information System (INIS)

    A novel process called nonisothermal method was developed by this work for the electroless Ni-P plating using operating temperature as high as 180 deg. C and even higher. Results obtained from measuring the open circuit potential (OCP) and the peak current of cyclic voltammetry (CV) indicated that a temperature depended thermal boundary layer with thickness of about 4-10 mm do exist by encompassing the heating substrate in our system. Based on the phenomena of the electrochemistry thermodynamics, the kinetic contour of a nonisothermal deposition (NITD) system could be described since the temperature profile of the thermal layer that governs the deposition reaction and the distance of the heat source with respect to the peak current of CV could be well correlated. The existence of the thermal boundary layer implied that the deposition reactions took place mainly within the thermal boundary layer itself rather than the bulk solution. By this method, the electroless Ni-P plating system even in the absence of the stabilizer can still be stably operated and it could even show two-fold deposition rate in comparison with the conventional method. Deposits performed by the NITD method having the phosphorous content at a level of 10-13% could exhibit a great enhancement on the physicochemical property and the microhardness from 500 up to 612 Hv0.1 as well

  10. The Effect of Adding Corrosion Inhibitors into an Electroless Nickel Plating Bath for Magnesium Alloys

    Science.gov (United States)

    Hu, Rong; Su, Yongyao; Liu, Hongdong; Cheng, Jiang; Yang, Xin; Shao, Zhongcai

    2016-08-01

    In this work, corrosion inhibitors were added into an electroless nickel plating bath to realize nickel-phosphorus (Ni-P) coating deposition on magnesium alloy directly. The performance of five corrosion inhibitors was evaluated by inhibition efficiency. The results showed that only ammonium hydrogen fluoride (NH4HF2) and ammonium molybdate ((NH4)2MoO4) could be used as corrosion inhibitors for magnesium alloy in the bath. Moreover, compounding NH4HF2 and (NH4)2MoO4, the optimal concentrations were both at 1.5 ~ 2%. The deposition process of Ni-P coating was observed by using a scanning electron microscope (SEM). It showed corrosion inhibitors inhibited undesired dissolution of magnesium substrate during the electroless plating process. In addition, SEM observation indicated that the corrosion inhibition reaction and the Ni2+ replacement reaction were competitive at the initial deposition time. Both electrochemical analysis and thermal shock test revealed that the Ni-P coating exhibited excellent corrosion resistance and adhesion properties in protecting the magnesium alloy.

  11. Electroless plating of PVC plastic through new surface modification method applying a semi-IPN hydrogel film

    Science.gov (United States)

    Wang, Ming-Qiu; Yan, Jun; Du, Shi-Guo; Li, Hong-Guang

    2013-07-01

    A novel palladium-free surface activation process for electroless nickel plating was developed. This method applied a semi-Interpenetrating Polymer Network (semi-IPN) hydrogel film to modify the poly(vinyl chloride) (PVC) surface by chemical bonds. The activation process involved the formation of semi-IPN hydrogel film on the PVC surface and the immobilization of catalyst for electroless plating linking to the pretreated substrate via Nsbnd Ni chemical bond. The hydrogel layer was used as the chemisorption sites for nickel ions, and the catalyst could initiate the subsequent electroless nickel plating onto the PVC surface. Finally, a Ni-P layer was deposited on the nickel-activated PVC substrate by electroless plating technique. The composition and morphology of nickel-plated PVC foils were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). The results of SEM and XRD show that a compact and continuous Ni-P layer with amorphous nickel phase is formed on the PVC surface. EDS shows that the content of the nickel and the phosphorus in the deposits is 89.4 wt.% and 10.6 wt.%, respectively.

  12. Electroless plating of PVC plastic through new surface modification method applying a semi-IPN hydrogel film

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ming-Qiu, E-mail: mqwang1514@163.com; Yan, Jun; Du, Shi-Guo; Li, Hong-Guang

    2013-07-15

    A novel palladium-free surface activation process for electroless nickel plating was developed. This method applied a semi-Interpenetrating Polymer Network (semi-IPN) hydrogel film to modify the poly(vinyl chloride) (PVC) surface by chemical bonds. The activation process involved the formation of semi-IPN hydrogel film on the PVC surface and the immobilization of catalyst for electroless plating linking to the pretreated substrate via N-Ni chemical bond. The hydrogel layer was used as the chemisorption sites for nickel ions, and the catalyst could initiate the subsequent electroless nickel plating onto the PVC surface. Finally, a Ni–P layer was deposited on the nickel-activated PVC substrate by electroless plating technique. The composition and morphology of nickel-plated PVC foils were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). The results of SEM and XRD show that a compact and continuous Ni–P layer with amorphous nickel phase is formed on the PVC surface. EDS shows that the content of the nickel and the phosphorus in the deposits is 89.4 wt.% and 10.6 wt.%, respectively.

  13. Electroless plating of PVC plastic through new surface modification method applying a semi-IPN hydrogel film

    International Nuclear Information System (INIS)

    A novel palladium-free surface activation process for electroless nickel plating was developed. This method applied a semi-Interpenetrating Polymer Network (semi-IPN) hydrogel film to modify the poly(vinyl chloride) (PVC) surface by chemical bonds. The activation process involved the formation of semi-IPN hydrogel film on the PVC surface and the immobilization of catalyst for electroless plating linking to the pretreated substrate via N-Ni chemical bond. The hydrogel layer was used as the chemisorption sites for nickel ions, and the catalyst could initiate the subsequent electroless nickel plating onto the PVC surface. Finally, a Ni–P layer was deposited on the nickel-activated PVC substrate by electroless plating technique. The composition and morphology of nickel-plated PVC foils were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). The results of SEM and XRD show that a compact and continuous Ni–P layer with amorphous nickel phase is formed on the PVC surface. EDS shows that the content of the nickel and the phosphorus in the deposits is 89.4 wt.% and 10.6 wt.%, respectively.

  14. Electroless Plating of Ni-Fe-P Alloy and Corrosion Resistance of the Deposit

    Institute of Scientific and Technical Information of China (English)

    Senlin WANG

    2005-01-01

    Electroless Ni-Fe-P alloys in an alkaline bath were plated. Theeffects of deposition parameters on the plating rate and the coating composition were examined. The weight loss test and the anodic polarization measurement of the deposits in 3.5 wt pct NaCl solution (pH7.0) showed that the deposits with the mole ratio of NiSO4/FeSO4 being 0.07:0.03, pH8.0 and 7.5 possess better corrosion resistance than that of the other deposits and the Ni-Fe-P deposits did not form passive films in this environment. In 5.0 wt pct NaOH solution, the Ni-Fe-P deposits have better corrosion resistance and formed passive films.

  15. Low-phosporous nickel-coated carbon microcoils: Controlling microstructure through an electroless plating process

    International Nuclear Information System (INIS)

    Carbon microcoils (CMCs) have been coated with a nickel-phosphorus (Ni-P) film using an electroless plating process, with sodium hypophosphite as a reducing agent in an alkaline bath. CMC composites have potential applications as microwave absorption materials. The morphology, elemental composition and phases in the coating layer of the CMCs and Ni-coated CMCs were investigated by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD), respectively. The effects of process parameters such as pH, temperature and coating time of the plating bath on the phosphorus content and deposition rate of the electroless Ni-P coating were studied. The results revealed that a continuous, uniform and low-phosphorous nickel coating was deposited on the surface of the CMCs for 20 min at pH 9.0, plating bath temperature 70 deg. C. The as-deposited coatings with approximately 4.5 wt.% phosphorus were found to consist of a mix of nano- and microcrystalline phases. The mean particle size of Ni-P nanoparticles on the outer surface of the CMCs was around 11.9 nm. The deposition rate was found to moderately increase with increasing pH, whereas, the phosphorous content of the deposit exhibited a significant decrease. Moreover, the material of the coating underwent a phase transition between an amorphous and a crystalline structure. The thickness of the deposit and the deposition rate may be controlled through careful variation of the coating time and plating bath temperature.

  16. Effect of plating time on growth of nanocrystalline Ni–P from sulphate/glycine bath by electroless deposition method

    Indian Academy of Sciences (India)

    N Latha; V Raj; M Selvam

    2013-08-01

    Nanocrystalline nickel phosphorus (NC-Ni–P) deposits from sulphate/glycine bath using a simple electroless deposition process is demonstrated. In the present investigation, nanoporous alumina films are formed on the aluminium surface by anodization process followed by deposition of nickel onto the pores by electroless plating method. Anodic aluminium oxide surface was first sensitized and activated by using palladium chloride solution before immersing into the electroless nickel bath. Electroless nickel plating was carried out from the optimized bath by changing the deposition time from 20 to 1800 s at a constant temperature of 80 °C and a pH of 4.0. Surface morphology, elemental composition, structure and reflectance of the deposits have been analysed by using scanning electron microscopy, atomic force microscopy, energy dispersive X-ray analysis, X-ray diffractometry and UV-visible spectroscopic studies, respectively. Electroless nickel deposits formed at an early stage produces dense uniform nanocrystals containing higher percentage of atomic phosphorus with cubic Ni (111) structure. As the deposition time increased, nanocrystalline sharp peak became amorphous and dimension of the crystal size varied from 54 to 72 nm.

  17. ELECTROLESS COPPER PLATING ON FRAXINUS MANDSHURICA VENEER USING GLYOXYLIC ACID AS REDUCING AGENT

    Directory of Open Access Journals (Sweden)

    Lijuan Wang

    2011-06-01

    Full Text Available 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.

  18. Electroless plating of nickel-phosphorous on surface-modified poly(ethylene terephthalate) films

    International Nuclear Information System (INIS)

    Chemical surface preparation for Ni-P electroless metallization of poly(ethylene terephthalate) (PET) films without using Chromium-based chemicals, was studied. The applicability of this method was verified by a subsequent metallization process. Thermal analysis was conducted to observe the main thermal transitions and stability of the polymer and metallized films. Contact angle analysis was performed to assess the surface hydrophilicity so as to optimize the substrate preparation process. X-ray diffraction, EDAX and SEM analysis were used to understand the composition and morphology of the polymeric substrate and Ni-P coat growing process. Adherence strength, contact sheet resistivity and optical diffuse reflection were measured on the metallized films. The time of chemical etching affects the polymer surface hydrophilicity, polymer/metal adherence strength, surface resistance and optical diffuse reflection, while Ni coating morphology is controlled by the pH of the electroless bath. High wettability of the polymer surface, adherence strength of 800 N cm-2, high optical diffuse reflection and low surface resistivity of the Ni coating, were found for films etched for 60 min. Metallizations performed at pH 7.5 produce Ni-P coatings with 12.0 wt.% phosphorous content, which were amorphous and flexible. The contact sheet resistivity of the plated films is sensitive to roughness variations of the substrate. The method proposed in this work allows the production of metallized films appropriate for the fabrication of flexible circuits

  19. Antibacterial characteristics of electroless plating Ni–P–TiO{sub 2} coatings

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Qi, E-mail: Q.Zhao@dundee.ac.uk [Department of Mechanical Engineering, University of Dundee, DD1 4HN (United Kingdom); Liu, Chen; Su, Xueju; Zhang, Shuai; Song, Wei; Wang, Su [Department of Mechanical Engineering, University of Dundee, DD1 4HN (United Kingdom); Ning, Guiling, E-mail: ninggl@dlut.edu.cn [State Key Laboratory of Fine Chemicals and School of Chemical Engineering, Dalian University of Technology, 2 Linggong Road, Dalian 116024 (China); Ye, Junwei; Lin, Yuan; Gong, Weitao [State Key Laboratory of Fine Chemicals and School of Chemical Engineering, Dalian University of Technology, 2 Linggong Road, Dalian 116024 (China)

    2013-06-01

    Electroless Ni–P coatings have been widely used in the chemical, mechanical and electronic industries due to their excellent corrosion and wear resistance. Many studies reported that the incorporation of nano-sized particles TiO{sub 2} into Ni–P matrix greatly improved their anti-corrosion and anti-wear resistance. However no studies have been reported on their anti-bacterial property. In this paper, the Ni–P–TiO{sub 2} nano-composite coatings were prepared on stainless steel 316L using electroless plating technique. The experimental results showed that the Ni–P–TiO{sub 2} coatings reduced the adhesion of three bacterial strains (Pseudomonas fluorescens, Cobetia and Vibrio) by up to 75% and 70% respectively, as compared with stainless steel and Ni–P coatings. The electron donor surface energy of the Ni–P–TiO{sub 2} coatings increased significantly with increasing TiO{sub 2} content after UV irradiation. The number of adhered bacteria decreased with increasing electron donor surface energy of the coatings.

  20. High-adhesion Cu patterns fabricated by nanosecond laser modification and electroless copper plating

    Science.gov (United States)

    Lv, Ming; Liu, Jianguo; Zeng, Xiaoyan; Du, Qifeng; Ai, Jun

    2015-10-01

    Adhesion strength is a crucial factor for the performance and reliability of metallic patterns on insulator substrates. In this study, we present an efficient technique for selective metallization of alumina ceramic with high adhesion strength by using nanosecond laser modification and electroless copper plating. Specifically, a 355 nm Nd:YVO4 ultraviolet (UV) laser was employed not only to decompose palladium chloride film locally for catalyzing the electroless reaction, but also to modify the ceramic surface directly using its high fluence. An orthogonal experiment was undertaken to study the effects of processing parameters including laser fluence, scanning speed and scanning line interval on adhesion strength. The adhesion strength was measured by pulling a metallic wire soldered into the copper coating perpendicular to the substrate using a pull tester. The results have shown that a strong adhesion between the copper coating and the alumina ceramic, higher than the tensile strength of tin-lead solder was obtained. Surface and interface characteristics were investigated to understand that, whose results have shown that the high-aspect-ratio microstructures formed by the laser modification is the major reason for the improvement of adhesion.

  1. Polyimide surface modification by using microwave plasma for adhesion enhancement of Cu electroless plating.

    Science.gov (United States)

    Cho, Sang-Jin; Nguyen, Trieu; Boo, Jin-Hyo

    2011-06-01

    Microwave (MW) plasma was applied to the surface of polyimide (PI) films as a treatment to enhance the adhesion between copper deposition layer and PI surface for electroless plating. The influences of nitrogen MW plasma treatment on chemical composition of the PI surface were investigated by using X-Ray photoelectron spectroscopy (XPS). The wettability was also investigated by water contact angle measurement. The surface morphologies of PI films before and after treatment were characterized with atomic force microscopy (AFM). The contact angle results show that was dramatically decreased to 16.1 degrees at the optimal treatment condition from 72.1 degrees (untreated PI). However, the root mean square (RMS) roughness of treated PI film was almost unchanged. The AFM roughness was stayed from 1.0 to 1.2 with/without plasma treatment. XPS data show a nitrogen increase when PI films exposed to N2 MW plasma. Electroless copper depositions were carried out with the free-formaldehyde method using glyoxylic acid as the reducing reagent and mixture palladium chloride, tin chloride as activation solution. Adhesion property between polyimide surface and copper layer was investigated by tape test. PMID:21770184

  2. Antibacterial characteristics of electroless plating Ni-P-TiO2 coatings

    Science.gov (United States)

    Zhao, Qi; Liu, Chen; Su, Xueju; Zhang, Shuai; Song, Wei; Wang, Su; Ning, Guiling; Ye, Junwei; Lin, Yuan; Gong, Weitao

    2013-06-01

    Electroless Ni-P coatings have been widely used in the chemical, mechanical and electronic industries due to their excellent corrosion and wear resistance. Many studies reported that the incorporation of nano-sized particles TiO2 into Ni-P matrix greatly improved their anti-corrosion and anti-wear resistance. However no studies have been reported on their anti-bacterial property. In this paper, the Ni-P-TiO2 nano-composite coatings were prepared on stainless steel 316L using electroless plating technique. The experimental results showed that the Ni-P-TiO2 coatings reduced the adhesion of three bacterial strains (Pseudomonas fluorescens, Cobetia and Vibrio) by up to 75% and 70% respectively, as compared with stainless steel and Ni-P coatings. The electron donor surface energy of the Ni-P-TiO2 coatings increased significantly with increasing TiO2 content after UV irradiation. The number of adhered bacteria decreased with increasing electron donor surface energy of the coatings.

  3. ADSORPTION PROPERTIES OF NICKEL-BASED MAGNETIC ACTIVATED CARBON PREPARED BY PD-FREE ELECTROLESS PLATING

    Directory of Open Access Journals (Sweden)

    Boyang Jia

    2011-02-01

    Full Text Available Nickel-based magnetic activated carbon was synthesized from coconut shell activated carbon by electroless plating with palladium-free activation. The effect of plating solution volume on metallic ratio and adsorption capacity were evaluated. The effect of metallic ratio on specific area, pore volume, and magnetic properties were investigated. The morphologies of activated carbon before and after plating were observed by SEM, and the composition of the layer was analyzed by EDS analysis. The results showed that the metallic ratio was increased with the increase of the plating solution volume. The magnetic activated carbon showed high adsorption capacity for methylene blue and a high iodine number. Those values reached 142.5 mg/g and 1035 mg/g, respectively. The specific area and pore volume decreased from 943 m2/g to 859 m2/g and 0.462 ml/g to 0.417 ml/g, respectively. And the layer was more compact and continuous when the metallic ratio reached 16.37 wt.%. In the layer, there was about 97 wt.% nickel and 3 wt.% phosphorus, which indicates that the layer was a low-phosphorus one. At the same time, magnetism was enhanced, making the product suitable for some special applications.

  4. Preparation of Ag-coated hollow microspheres via electroless plating for application in lightweight microwave absorbers

    Science.gov (United States)

    Kim, Wook-Joong; Kim, Sung-Soo

    2015-02-01

    Highly conductive Ag film is coated on hollow silica microspheres via electroless plating for application in lightweight microwave absorbers. The Ag plating is conducted using a two-step process of sensitizing and subsequent plating. The complex permeability and permittivity are determined using the reflection/transmission technique in the composite specimens of Ag-coated microspheres and silicone rubber matrix. Due to the large surface area of the microspheres, a relatively high concentration of AgNO3 is required in order to achieve a uniform Ag coating. In addition, a low concentration of fructose reducing agent is recommended for slow plating. The apparent electrical resistance of the Ag-coated microspheres is strongly dependent on the grain morphology. The thin and uniform Ag-coated particles are characterized by their low electrical resistance, which is as low as 0.1 Ω. The lower the electrical resistance of the microspheres, the higher the dielectric constant of the composite specimens, which results from the enhanced space-charge polarization between the conductive microspheres. The microwave absorbance is enhanced with decreases in the electrical resistance of microspheres due to the increased dielectric loss.

  5. Study on corrosion resistance of palladium films on 316L stainless steel by electroplating and electroless plating

    International Nuclear Information System (INIS)

    Palladium films with good adhesive strength were deposited on 316L stainless steel by electroless plating and electroplating. Scanning electronic microscopy, energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, weight loss tests and electrochemical methods were used to study the properties of the films. The electroless plated palladium film mainly consisted of palladium, phosphorus and nitrogen, and the electroplated palladium film was almost pure palladium. XPS analysis indicated that palladium was present in the films as metal state. The palladium plated stainless steel samples prepared by both methods showed excellent corrosion resistance in strong reductive corrosion mediums. In boiling 20% dilute sulfuric acid solution, the corrosion rates of the palladium plated 316L stainless steel samples were four orders of magnitude lower than that of the original 316L stainless steel samples. In the solution with 0.01 M NaCl, the palladium plated samples also showed better corrosion resistance. In comparison, the electroplated samples showed slightly better corrosion resistance than electroless plated samples, which may be attributed to less impurities and thereby higher corrosion potential for the former

  6. Microwire formation based on dielectrophoresis of electroless gold plated polystyrene microspheres

    Institute of Scientific and Technical Information of China (English)

    Jiang Hong-Yuan; Ren Yu-Kun; Tao Ye

    2011-01-01

    Microspheres coated with a perfectly conductive surface have many advantages in the applications of biosensors and micro-electromechanical systems. Polystyrene microspheres with the diameter of 10 μm were coated with a 50 nmthick gold layer using an electroless gold plating approach. Dielectrophoresis (DEP) for bare microspheres and shelled microspheres was theoretically analysed and the real part of the Clausius-Mossotti factor was calculated for the two kinds of microspheres. The experiments on the dielectrophoretic characterisation of the uncoated polystyrene microspheres and gold coated polystyrene microspheres (GCPMs) were carried out. Experimental results showed that the gold coated polystyrene microspheres were only acted by a positive dielectrophoretic force when the frequency was below 40M Hz,while the uncoated polystyrene microspheres were governed by a negative dielectrophoretic force in this frequency range.The gold coated polystyrene microspheres were exploited to form the microwire automatically according to their stable dielectrophoretic and electric characterisations.

  7. Research on Processes and Adhesion of Electroless Plating Ni-Cu-P Coating

    Institute of Scientific and Technical Information of China (English)

    HUANG Yan-bin; LIU Bo; ZHANG Ping; LIU De-gang; XU Xiao-li

    2004-01-01

    In order to improve the corrosion and wear resistance of the coatings of electroless plating Ni-Cu-P and broaden its application, an optimizing mathematical theory test has been applied in this research. The processing parameters have been optimized and some Ni-Cu-P coatings have been obtained with smooth and glittering appearance. At the same time,the composite complexants can prevent copper from depositing first and obtain coatings with strong adhesion. The porosity of Ni-Cu-P coating (20 μm) ranked class 9. The changing color time of the coating is more than 800 seconds with HNO3 dropthan 0.5 g/L. The surface appearance of deposition is typical cystiform cells by SEM,which rank close and neatly.

  8. Preparation, characterization and wear behavior of carbon coated magnesium alloy with electroless plating nickel interlayer

    Science.gov (United States)

    Mao, Yan; Li, Zhuguo; Feng, Kai; Guo, Xingwu; Zhou, Zhifeng; Dong, Jie; Wu, Yixiong

    2015-02-01

    Poor wear resistance of rare earth magnesium alloys has prevented them from wider application. In this study, composite coating (PVD carbon coating deposited on electroless plating nickel interlayer) is prepared to protect GW83 magnesium alloys against wear. The Ni + C composite coating has a dense microstructure, improved adhesion strength and hardness due to the effective support of Ni interlayer. The wear test result shows that the Ni + C composite coating can greatly prolong the wear life of the magnesium alloy. The wear track of the Ni + C coated magnesium alloy is obviously narrower and shows less abrasive particles as compared with the bare one. Abrasive wear is the wear mechanism of the coatings at the room temperature. In conclusion, the wear resistance of the GW83 magnesium alloy can be greatly improved by the Ni + C composite coating.

  9. Electroless nickel plating of arc discharge synthesized carbon nanotubes for metal matrix composites

    Science.gov (United States)

    Jagannatham, M.; Sankaran, S.; Prathap, Haridoss

    2015-01-01

    Electroless nickel (EN) plating was performed on arc discharge synthesized multiwalled carbon nanotubes for various deposition times. X-ray diffraction (XRD), Transmission electron microscopy (TEM), and Raman spectroscopy characterization techniques are used to identify the presence of nickel deposition on the carbon nanotubes (CNTs) and the degree of graphitization. The results indicate that impurities are less in the purified CNTs as compared to raw carbon soot. Increasing deposition time up to 60 min increases uniform deposition of nickel throughout the length of the CNTs. However, for deposition time longer than 60 min, nickel particles are seen separated from the surface of the CNTs. Uniformly coated nickel CNTs throughout their length are potential candidates for reinforcements in composite materials. Magnetic properties of the nickel coated CNTs, with deposition time of 30 and 60 min were also evaluated. The magnetic saturation of nickel coated CNTs with deposition time of 30 min is less compared to nickel coated CNTs with deposition time of 60 min.

  10. Wear and Corrosion Resistance of Electroless Plating Ni-P Coating on P110 Steel

    Institute of Scientific and Technical Information of China (English)

    LIN Naiming; ZHOU Peng; ZOU Jiaojuan; XIE Faqin; TANG Bin

    2015-01-01

    In order to improve the surface performance and increase the lifetime of P110 oil casing tube steel during operation, electroless plating was conducted to form Ni-P coating onto its surface. The surface morphology/element distribution and phase constitution of the Ni-P coating were analyzed using scanning electron microscope (SEM) equipped with energy dispersive spectrometry (EDS) and X-ray diffraction (XRD). Tribological and electrochemical measurement tests were applied to investigate the wear and corrosion resistance of P110 steel and the Ni-P coating. The results showed that a uniform and compact, high phosphorous Ni-P coating was formed. The obtained Ni-P coating indicated certain friction-reduction effect and lower mass loss during friction-wear tests. The Ni-P coating also exhibited higher corrosion resistance in comparison with bared P110 steel. The obtained Ni-P coating has signifi cantly improved the surface performance of P110 steel.

  11. Electroless copper plating on 3-mercaptopropyltriethoxysilane modified PET fabric challenged by ultrasonic washing

    International Nuclear Information System (INIS)

    Electroless deposition of Cu on poly(ethylene terephthalate) (PET) fabric modified with 3-mercaptopropyltriethoxysilane was investigated. Morphology, composition, structure, thermal decomposing behavior of copper coating PET fabric after ultrasonic washing in water for 1 h were characterized by scanning electron microscopy (SEM), energy dispersive X-ray (EDX) analysis, X-ray photoelectron spectroscopy (XPS), Raman spectrometer, X-ray diffraction (XRD), and thermogravimetric analysis (TG), respectively. Copper plating on modified fabric has good adherence stability and high electric conductivity before and after ultrasonic washing, while copper coating fabric without modification is easily destroyed during the washing process, which leads to the textile changing from conductor to dielectric. As the copper weight on the treated fabric is 28 g/m2, the shielding effectiveness (SE) is more than 54 dB at frequency ranging from 0.01 MHz to 18 GHz.

  12. Study of palladium catalyzation for electroless copper plating on polyimide film.

    Science.gov (United States)

    Kim, Bin; Jung, Sang Hee; Suh, Seung Wook; Park, Byung Ki

    2013-01-01

    In order to form flexible printed circuits through inkjet printing technique, the Pd(ll) catalyst ink was printed on the surface of polyimide film modified with KOH solution and then reduced with NaBH4 solution to extract the Pd(O) catalyst nuclei. The concentration of the Pd(ll) catalyst ink and reduction time showed a significant influence on the microstructure of the Pd(O) catalyst nuclei and the formation of Cu patterns through electroless plating. When reduction time exceeded 1 minute, and as the concentration of the Pd(II) catalyst ink increased above 0.02 M, the catalyst nuclei began aggregation, resulting in Cu patterns with thick and more defects. PMID:23646765

  13. Microstructure evolution and magnetic properties of Co-B coatings electrolessly plated on hollow microspheres

    International Nuclear Information System (INIS)

    The composites of Co-B coatings on hollow microspheres (Co-B/HMSs) have been successfully synthesized through electroless plating in this paper. The time-dependent microstructure evolution and magnetic properties of the composites were carefully investigated by scanning electron microscope (SEM), energy dispersive X-ray (EDX), and X-ray photoelectron spectroscopy (XPS) and vibrating sample magnetometer (VSM). It was found that small Co-B clusters appeared on the surface of hollow microspheres at catalytic nuclei during the initial stage. Further growth, they converged to form continuous coatings, which were actually stacking of Co-B nuclei. Interestingly, there was an increment of B content in the coating as time wore on, this phenomenon could be interpreted by electrochemical mechanism. Besides, the composites showed magnetic properties, which might be potentially important for the novel materials as magnetic carriers.

  14. A novel silver-coated solid-phase microextraction metal fiber based on electroless plating technique.

    Science.gov (United States)

    Feng, Juanjuan; Sun, Min; Li, Jubai; Liu, Xia; Jiang, Shengxiang

    2011-09-01

    A novel silver-coated solid-phase microextraction fiber was prepared based on electroless plating technique. Good extraction performance of the fiber for model compounds including phthalate esters (dibutyl phthalate, dioctyl phthalate, dicyclohexyl phthalate and diallyl phthalate) and polycyclic aromatic hydrocarbons (naphthalene, fluorene, phenanthrene, fluoranthene) in aqueous solution was obtained. Under the optimized conditions (extraction temperature, extraction time, ionic strength and desorption temperature), the proposed SPME-GC method showed wide linear ranges with correlation coefficients (R(2)) ranging from 0.9745 to 0.9984. The limits of detection were at the range of 0.02 to 0.1 μg L(-1). Single fiber repeatability and fiber-to-fiber reproducibility as well as stability to acid, alkali and high temperature were studied and the results were all satisfactory. The method was applied successfully to the aqueous extracts of disposable paper cup and instant noodle barrel. Several kinds of analytes were detected and quantified. PMID:21801885

  15. Electroless plating of noble metal nanoparticles for improved performance of silicon photodiodes via surface plasmon resonance

    Energy Technology Data Exchange (ETDEWEB)

    Blackwood, D.J.; Khoo, S.M. [Department of Materials Science and Engineering, National University of Singapore, 9 Engineering Drive 1, Singapore 117576 (Singapore)

    2010-07-15

    Surface plasmon resonance from noble metal nanoparticles is a promising way to improve the efficiencies of silicon based photodiodes and solar cells. Electroless plating is an extremely simple technique for producing such metallic nanoparticles. It is found that the deposition of gold on Si photodiodes occurs as chains that drastically reduce the photodiodes conversion efficiency. However, silver deposits as nano-islands that are efficient SPR centers, which improve the performance of Si photodiodes in the visible region; as measured by both IPCE and I-V curves. The greatest improvement observed was a 3.5% increase in J{sub sc} under solar irradiation. Although this improvement is lost upon annealing it can be regained by a further treatment in acidified HAuCl{sub 4}. Possible explanations for these latter two behaviors are proposed. (author)

  16. Fabrication of silver nanosheets on quartz glass substrates through electroless plating approach

    Science.gov (United States)

    Yi, Zao; Xu, Xibin; Fang, Qi; Wang, Yuying; Li, Xibo; Tan, Xiulan; Luo, Jiangshan; Jiang, Xiaodong; Wu, Weidong; Yi, Yougen; Tang, Yongjian

    2014-02-01

    Silver nanosheets (NSs) have been synthesized by an electroless plating approach using a complexation mechanism of triethanolamine (TEA) and Ag+ to reduce the oxidation-reduction potential difference and slow down the deposition speed of Ag on quartz glass substrates. The synthesized Ag NSs with 500 nm in edge length and 30 nm in thickness stand on the substrates and are dispersed uniformly. The formation mechanism of Ag NSs is proposed. The formation of Ag NSs is attributed to the molar ratio of AgNO3 to TEA, the concentration of AgNO3 and the influence of reaction temperature. This study is important in vertical immobilization Ag NSs on solid substrates, which could provide substrates for catalysis or surface-enhanced Raman scattering.

  17. Synthesis and microwave characterization of Co-SiC core-shell powders by electroless plating

    Institute of Scientific and Technical Information of China (English)

    ZHANG Haijun; WU Xiangwei; JIA Quanli; JIA Xiaolin

    2006-01-01

    Co-SiC core-shell powders were prepared by electroless plating. Scanning electron microscopy (SEM) revealed that Co-SiC core-shell powders were of nearly sphere-like shape and were about 0.3 μm. X-ray powder diffraction (XRD)patterns showed that the cobalt powder was hexagonal crystallite. The complex dielectric constant and the complex permeability of Co-SiC core-shell powders-paraffin wax composite were measured by the rectangle waveguide method. It showed that the dielectric loss was less than 0.1 and the magnetic loss was about 0.2 in 8.2-12.4 GHz for prepared Co-SiC core-shell composite powders.

  18. Tribological behavior of dual-layer electroless-plated Ag–carbon nanotube coatings

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hyun-Dai [Department of Mechanical Engineering, Yonsei University, Seoul 120-749 (Korea, Republic of); Penkov, Oleksiy V. [Center for Nano-Wear, Yonsei University, Seoul 120-749 (Korea, Republic of); Kim, Dae-Eun, E-mail: kimde@yonsei.ac.kr [Department of Mechanical Engineering, Yonsei University, Seoul 120-749 (Korea, Republic of)

    2013-05-01

    The tribological behavior of electroless Ag-plated carbon nanotube (CNT) dual-layer coatings was assessed and compared to that of the pure CNT coating. The motivation was to protect the surface of CNT coatings from wear by depositing a thin, soft Ag coating. The methods used for coating CNTs and Ag were spin coating and electroless plating, respectively. These coating methods were selected based on their simplicity and cost effectiveness. Wear tests were conducted by sliding the coatings against a stainless steel ball under a 10–30 mN applied load. Results showed that the wear rate of the dual-layer coating was strongly dependent on the thickness of the Ag layer as well as the applied load. At a 10 mN load and an Ag thickness of 65 nm, the wear rate of the dual-layer coating was about 10 times less than that of the pure CNT coating. However, when the thickness of the Ag was decreased to 11.5 nm, the wear rate was significantly higher. Also, the steady-state friction coefficients of the CNT and the dual-layer Ag–CNT coatings were in the range of 0.65–0.73 for all loads. A model of the wear reduction mechanism of the dual-layer Ag–CNT coating was proposed. - Highlights: ► Dual-layer Ag–carbon nanotube (CNT) coatings were deposited on silicon wafer. ► Friction coefficient of the Ag–CNT coatings was about 0.65. ► Wear of Ag–CNT coatings depended on the thickness of Ag layer and the applied load. ► Wear rate of the Ag–CNT coating was 10-fold less than that of the pure CNT coating.

  19. Tribological behavior of dual-layer electroless-plated Ag–carbon nanotube coatings

    International Nuclear Information System (INIS)

    The tribological behavior of electroless Ag-plated carbon nanotube (CNT) dual-layer coatings was assessed and compared to that of the pure CNT coating. The motivation was to protect the surface of CNT coatings from wear by depositing a thin, soft Ag coating. The methods used for coating CNTs and Ag were spin coating and electroless plating, respectively. These coating methods were selected based on their simplicity and cost effectiveness. Wear tests were conducted by sliding the coatings against a stainless steel ball under a 10–30 mN applied load. Results showed that the wear rate of the dual-layer coating was strongly dependent on the thickness of the Ag layer as well as the applied load. At a 10 mN load and an Ag thickness of 65 nm, the wear rate of the dual-layer coating was about 10 times less than that of the pure CNT coating. However, when the thickness of the Ag was decreased to 11.5 nm, the wear rate was significantly higher. Also, the steady-state friction coefficients of the CNT and the dual-layer Ag–CNT coatings were in the range of 0.65–0.73 for all loads. A model of the wear reduction mechanism of the dual-layer Ag–CNT coating was proposed. - Highlights: ► Dual-layer Ag–carbon nanotube (CNT) coatings were deposited on silicon wafer. ► Friction coefficient of the Ag–CNT coatings was about 0.65. ► Wear of Ag–CNT coatings depended on the thickness of Ag layer and the applied load. ► Wear rate of the Ag–CNT coating was 10-fold less than that of the pure CNT coating

  20. Study on Physical and Chemical Behaviors of Rare Earths in Preparing Ceramic Tube Supported Palladium Film by Electroless Plating

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The rare earths of ytterbium, lanthanum, praseodymium, neodymium and their binary mixtures were respectively added into the traditional electroless plating solution to prepare thin palladium film on the inner surface of porous ceramic tube. The experimental results shows that the addition of rare earths increases palladium deposition rates and the binary mixtures are superior to the single rare earths and the mixture of ytterbium-lanthanum is the most efficient. Adding the mixture of ytterbium-lanthanum can also reduce the plating temperature by 10~20 ℃, shrink the metal crystal size and improve the film densification compared to those by traditional electroless plating. A thin palladium film with 5 μm was prepared and the film made a highly pure hydrogen with a molar fraction of more than 99.97% from a H2-N2 gas mixture. More attentions were paid to analyze the physical and chemical behaviors of the rare earths in palladium film preparation.

  1. Effects of bath composition on the morphology of electroless-plated Cu electrodes for hetero-junctions with intrinsic thin layer solar cell

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Woon Young [Surface Technology R& BD Group, Korea Institute of Industrial Technology (KITECH), Gaetbeol-ro 156, Yeonsu-gu, Incheon 406-840 (Korea, Republic of); Lee, Yu Jin [Surface Technology R& BD Group, Korea Institute of Industrial Technology (KITECH), Gaetbeol-ro 156, Yeonsu-gu, Incheon 406-840 (Korea, Republic of); Department of Materials Science & Engineering, Yonsei University, Yonsei-ro 50, Seodaemun-Gu, Seoul 120-749 (Korea, Republic of); Lee, Min Hyung, E-mail: minhyung@kitech.re.kr [Surface Technology R& BD Group, Korea Institute of Industrial Technology (KITECH), Gaetbeol-ro 156, Yeonsu-gu, Incheon 406-840 (Korea, Republic of)

    2015-07-31

    The morphology of an electroless-plated Cu electrode was investigated as a function of bath composition. To enhance the selectivity of Cu electrode deposition on the surface of an indium tin oxide layer, a Ti/Cu multi-layer was deposited as a Cu electrode seed layer by physical vapor deposition, and then electroless plating was performed using various complexing agents and a surfactant. The degree of selectivity was effectively influenced by the type of complexing agent. The electroless plating solution containing N,N,N′,N′-tetrakis(2-hydroxypropyl)ethylenediamine (THPED) as complexing agent showed excellent selective growth of the Cu electrode as compared to the solution containing ethylenediaminetetraacetic acid. Even though THPED led to better selective growth of the electroless-plated Cu electrode, the aspect ratio of electrode lateral growth was about 2.7 times that of vertical growth. By adding a nonionic surfactant, the ratio between vertical growth rate and lateral growth rate was improved about 4.6 times. The Cu–THPED electroless plating with nonionic surfactant provided a drastic decrease in lateral growth rate, compared with the Cu–THPED electroless plating bath excluding nonionic surfactant. The Cu–THPED solution including nonionic surfactant is a promising composition of electroless plating solution for the clear selective plating of Cu electrodes on hetero-junctions with intrinsic thin layer solar cells. - Highlights: • Selective electroless plating (SEP) depends on binding strength of complexing agent. • The SEP was performed using Cu-N,N,N′,N′-tetrakis(2-hydroxypropyl)ethylenediamine. • A surfactant is able to remove hydrogen bubbles on Cu electrode surface. • The growth of Cu electrode was improved in vertical direction by adding surfactant.

  2. Effects of bath composition on the morphology of electroless-plated Cu electrodes for hetero-junctions with intrinsic thin layer solar cell

    International Nuclear Information System (INIS)

    The morphology of an electroless-plated Cu electrode was investigated as a function of bath composition. To enhance the selectivity of Cu electrode deposition on the surface of an indium tin oxide layer, a Ti/Cu multi-layer was deposited as a Cu electrode seed layer by physical vapor deposition, and then electroless plating was performed using various complexing agents and a surfactant. The degree of selectivity was effectively influenced by the type of complexing agent. The electroless plating solution containing N,N,N′,N′-tetrakis(2-hydroxypropyl)ethylenediamine (THPED) as complexing agent showed excellent selective growth of the Cu electrode as compared to the solution containing ethylenediaminetetraacetic acid. Even though THPED led to better selective growth of the electroless-plated Cu electrode, the aspect ratio of electrode lateral growth was about 2.7 times that of vertical growth. By adding a nonionic surfactant, the ratio between vertical growth rate and lateral growth rate was improved about 4.6 times. The Cu–THPED electroless plating with nonionic surfactant provided a drastic decrease in lateral growth rate, compared with the Cu–THPED electroless plating bath excluding nonionic surfactant. The Cu–THPED solution including nonionic surfactant is a promising composition of electroless plating solution for the clear selective plating of Cu electrodes on hetero-junctions with intrinsic thin layer solar cells. - Highlights: • Selective electroless plating (SEP) depends on binding strength of complexing agent. • The SEP was performed using Cu-N,N,N′,N′-tetrakis(2-hydroxypropyl)ethylenediamine. • A surfactant is able to remove hydrogen bubbles on Cu electrode surface. • The growth of Cu electrode was improved in vertical direction by adding surfactant

  3. Modeling, Fabrication and Characterization of Scalable Electroless Gold Plated Nanostructures for Enhanced Surface Plasmon Resonance

    Science.gov (United States)

    Jang, Gyoung Gug

    The scientific and industrial demand for controllable thin gold (Au) film and Au nanostructures is increasing in many fields including opto-electronics, photovoltaics, MEMS devices, diagnostics, bio-molecular sensors, spectro-/microscopic surfaces and probes. In this study, a novel continuous flow electroless (CF-EL) Au plating method is developed to fabricate uniform Au thin films in ambient condition. The enhanced local mass transfer rate and continuous deposition resulting from CF-EL plating improved physical uniformity of deposited Au films and thermally transformed nanoparticles (NPs). Au films and NPs exhibited improved optical photoluminescence (PL) and surface plasmon resonance (SPR), respectively, relative to batch immersion EL (BI-EL) plating. Suggested mass transfer models of Au mole deposition are consistent with optical feature of CF-EL and BI-EL films. The prototype CF-EL plating system is upgraded an automated scalable CF-EL plating system with real-time transmission UV-vis (T-UV) spectroscopy which provides the advantage of CF-EL plating, such as more uniform surface morphology, and overcomes the disadvantages of conventional EL plating, such as no continuous process and low deposition rate, using continuous process and controllable deposition rate. Throughout this work, dynamic morphological and chemical transitions during redox-driven self-assembly of Ag and Au film on silica surfaces under kinetic and equilibrium conditions are distinguished by correlating real-time T-UV spectroscopy with X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) measurements. The characterization suggests that four previously unrecognized time-dependent physicochemical regimes occur during consecutive EL deposition of silver (Ag) and Au onto tin-sensitized silica surfaces: self-limiting Ag activation; transitory Ag NP formation; transitional Au-Ag alloy formation during galvanic replacement of Ag by Au; and uniform morphology formation under

  4. The study of electroless Ni-W-P alloy plating on glass fibers

    Institute of Scientific and Technical Information of China (English)

    HUANG Ying; HUANG Fei; ZHAO Wentao; SHI Ke; ZHAO Li; WANG Yanli

    2007-01-01

    Ni-W-P coatings were deposited on the surface of glass fibers by the electroless plating process. The bath was very stable through the palladium salt test. There was no phenomenon of peeling and blistering on the surface of the Ni-W-P alloy glass fibers in the thermal shock test. It showed that the deposit had high impact strength and good adhesion. The morphology of the coatings was observed by scanning electron microscope (SEM). The elements and their contents were tested and analyzed by energy dispersion spectrometer (EDS). The tungsten content reached up to 12.1 wt.%. The effects of results indicated that the deposit had an amorphous structure and good heat stability. The suitable work temperature range was lower than 190℃. Finally, the electromagnetic parameters of the Ni-W-P alloy glass fibers were tested and analyzed primarily. The magnetic loss reached 0.04023 and the dielectric loss reached -5.80239. The plated alloy is a kind of soft magnetic material.

  5. Microscopic study of a ligand induced electroless plating process onto polymers.

    Science.gov (United States)

    Garcia, Alexandre; Berthelot, Thomas; Viel, Pascal; Polesel-Maris, Jérôme; Palacin, Serge

    2010-11-01

    The ligand induced electroless plating (LIEP) process was recently developed and thoroughly demonstrated with one of the most used polymers for plating processes: acrylonitrile-butadiene-styrene (ABS). This generic process is based, thanks to the use of diazonium salts as precursors, on the covalent grafting of a thin layer of poly(acrylic acid) (PAA) acting as ligand for metallic salts onto pristine polymer surfaces. This strategy takes advantage of the PAA ion exchange properties. Indeed, carboxylate groups contained in PAA allow one to complex copper ions which are eventually reduced and used as catalysts of the metallic deposition. Essentially based on ABS, ABS-PC (ABS-polycarbonate) and PA (polyamide) substrates, the present paper focuses on the role of the polymer substrate and the relationships between the macroscopic properties and microscopic characterizations such as infrared (IR), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and scanning electron microscopy (SEM). The adhesion strength of the metallic layer deposited via that LIEP process with the bulk polymer substrates was successfully compared with the adhesion of similar copper films deposited by the usual process based on chromic acid etching and palladium-based seed layer, by measuring the T-peel adhesion strength, and by carrying out the common industrial scotch tape test. Lastly, the electrical properties of the deposited layer were studied thanks to a four-point probe and scanning tunneling microscopy (STM) measurements. PMID:21053943

  6. Preparation and characterization of monodispersed PS/Ag composite microspheres through modified electroless plating

    International Nuclear Information System (INIS)

    A modified electroless silver-plating process has been devised for the preparation of monodispersed, polystyrene/silver (PS/Ag) composite microspheres with tunable shell thickness. Tailoring was achieved by altering the concentration of the silver precursor in the plating bath. PS/Ag composite microspheres were characterized by field-emission scanning electron microscopy, ultraviolet-visible absorption, X-ray diffraction and thermogravimetric analysis. The results showed that a dense, stable and uniform silver nanoshell was formed on the surface of PS microspheres in the presence of poly(vinylpyrrolidone) and glucose. The bulk conductivity of the PS/Ag composites increased from 1.16 S/m to 3.57 × 104 S/m, corresponding to a shell thickness of 35-198 nm. The PS/Ag composite microspheres with diameters of ca. 3 μm might have great potential to be used as fillers in anisotropic conductive films because of the uniform diameter, low density and good conductivity of the microspheres.

  7. Preparation and characterization of monodispersed PS/Ag composite microspheres through modified electroless plating

    Science.gov (United States)

    Ma, Yuehui; Zhang, Qinghua

    2012-07-01

    A modified electroless silver-plating process has been devised for the preparation of monodispersed, polystyrene/silver (PS/Ag) composite microspheres with tunable shell thickness. Tailoring was achieved by altering the concentration of the silver precursor in the plating bath. PS/Ag composite microspheres were characterized by field-emission scanning electron microscopy, ultraviolet-visible absorption, X-ray diffraction and thermogravimetric analysis. The results showed that a dense, stable and uniform silver nanoshell was formed on the surface of PS microspheres in the presence of poly(vinylpyrrolidone) and glucose. The bulk conductivity of the PS/Ag composites increased from 1.16 S/m to 3.57 × 104 S/m, corresponding to a shell thickness of 35-198 nm. The PS/Ag composite microspheres with diameters of ca. 3 μm might have great potential to be used as fillers in anisotropic conductive films because of the uniform diameter, low density and good conductivity of the microspheres.

  8. Preparation and characterization of monodispersed PS/Ag composite microspheres through modified electroless plating

    Energy Technology Data Exchange (ETDEWEB)

    Ma Yuehui [State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620 (China); Zhang Qinghua, E-mail: qhzhang@dhu.edu.cn [State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620 (China)

    2012-07-15

    A modified electroless silver-plating process has been devised for the preparation of monodispersed, polystyrene/silver (PS/Ag) composite microspheres with tunable shell thickness. Tailoring was achieved by altering the concentration of the silver precursor in the plating bath. PS/Ag composite microspheres were characterized by field-emission scanning electron microscopy, ultraviolet-visible absorption, X-ray diffraction and thermogravimetric analysis. The results showed that a dense, stable and uniform silver nanoshell was formed on the surface of PS microspheres in the presence of poly(vinylpyrrolidone) and glucose. The bulk conductivity of the PS/Ag composites increased from 1.16 S/m to 3.57 Multiplication-Sign 10{sup 4} S/m, corresponding to a shell thickness of 35-198 nm. The PS/Ag composite microspheres with diameters of ca. 3 {mu}m might have great potential to be used as fillers in anisotropic conductive films because of the uniform diameter, low density and good conductivity of the microspheres.

  9. Electroless plating of silver nanoparticles on porous silicon for laser desorption/ionization mass spectrometry

    Science.gov (United States)

    Yan, Hong; Xu, Ning; Huang, Wen-Yi; Han, Huan-Mei; Xiao, Shou-Jun

    2009-03-01

    An improved DIOS (desorption ionization on porous silicon) method for laser desorption/ionization mass spectrometry (LDI MS) by electroless plating of silver nanoparticles (AgNPs) on porous silicon (PSi) was developed. By addition of 4-aminothiophenol (4-ATP) into the AgNO3 plating solution, the plating speed can be slowed down and simultaneously 4-ATP self-assembled monolayers (SAMs) on AgNPs (4-ATP/AgNPs) were formed. Both AgNPs and 4-ATP/AgNPs coated PSi substrates present much higher stability, sensitivity and reproducibility for LDI MS than the un-treated porous silicon ones. Their shelf life in air was tested for several weeks to a month and their mass spectra still displayed the same high quality and sensitivity as the freshly prepared ones. And more 4-ATP SAMs partly play a role of matrix to increase the ionization efficiency. A small organic molecule of tetrapyridinporphyrin (TPyP), oligomers of polyethylene glycol (PEG 400 and 2300), and a peptide of oxytocin were used as examples to demonstrate the feasibility of the silver-plated PSi as a matrix-free-like method for LDI MS. This approach can obtain limits of detection to femtomoles for TPyP, subpicomoles for oxytocin, and picomoles for PEG 400 and 2300, comparable to the traditional matrix method and much better than the DIOS method. It simplifies the sample preparation as a matrix-free-like method without addition of matrix molecules and homogenizes the sample spread over the spot for better and more even mass signals.

  10. Electroless Plating of Thin Silver Films on Porous Al2O3 Substrate and the Study of Deposition Kinetics

    Institute of Scientific and Technical Information of China (English)

    Fang Mei; Donglu Shi

    2005-01-01

    A novel concept has been developed to coat the inner pore surfaces of reticulated alumina with a thin silver film by an electroless-plating method. As a result of coating, the porous alumina sample exhibits a sharp transition from insulating to conducting due to a thin silver layer on the inner pore surfaces. Systematic studies have been carried out to investigate the coating kinetics by employment of scanning electron microscope (SEM), X-ray diffraction (XRD), and computer simulation. Both coating procedures and effects of processing parameters on the quality of films are reported. Also, this paper presents the film bonding strength to the substrate, effects of sintering, and conduction mechanism of coated composite. The fundamental silver electroless-plating mechanism has been identified based on computer modeling. The simulation results indicate an excellent agreement between the silver deposition behavior and the physical model applied.

  11. Inkjet-printing- and electroless-plating- based fabrication of RF circuit structures on high-frequency substrates

    International Nuclear Information System (INIS)

    In this paper, a method to fabricate radio frequency (RF) circuit structures is described. This method involves inkjet printing of a silver nanoparticle-based ink on a functional substrate material to create the seed track (i.e., the seed layer), onto which copper is subsequently deposited by an electroless plating method, to obtain the desired thickness and conductivity of the RF structures. This process combination was validated by fabricating an S-band filter on a high-frequency substrate and comparing the RF performance of this filter with that of a filter fabricated using the conventional lithography-based method. The adhesion of the circuit structures to the substrate was qualitatively ascertained by the scotch tape test method. The performance of the inkjet-printed–electroless-plated filter was comparable to that of the conventional filter, thus proving the suitability of this novel method for practical RF applications

  12. Inkjet-printing- and electroless-plating- based fabrication of RF circuit structures on high-frequency substrates

    Science.gov (United States)

    Sridhar, A.; Reiding, J.; Adelaar, H.; Achterhoek, F.; van Dijk, D. J.; Akkerman, R.

    2009-08-01

    In this paper, a method to fabricate radio frequency (RF) circuit structures is described. This method involves inkjet printing of a silver nanoparticle-based ink on a functional substrate material to create the seed track (i.e., the seed layer), onto which copper is subsequently deposited by an electroless plating method, to obtain the desired thickness and conductivity of the RF structures. This process combination was validated by fabricating an S-band filter on a high-frequency substrate and comparing the RF performance of this filter with that of a filter fabricated using the conventional lithography-based method. The adhesion of the circuit structures to the substrate was qualitatively ascertained by the scotch tape test method. The performance of the inkjet-printed-electroless-plated filter was comparable to that of the conventional filter, thus proving the suitability of this novel method for practical RF applications.

  13. Selective deposition of conductive copper films on glass surfaces using femtosecond laser surface modification and electroless plating

    Science.gov (United States)

    Xu, Jian; Liao, Yang; Zeng, Huidan; Zhou, Zenghui; Sun, Haiyi; Song, Juan; Wang, Xinshun; Cheng, Ya; Xu, Zhizhan; Sugioka, Koji; Midorikawa, Katsumi

    2008-03-01

    In this paper, selective deposition of conductive copper films on glass surfaces is demonstrated with the assistance of femtosecond laser surface modification followed by electroless plating. Irradiation of femtosecond laser makes it possible to selectively deposit copper films in the irradiated area on glass surfaces coated with silver nitrate films. The influence of the laser direct writing parameters and the electroless plating process on the formation of copper films is discussed. Meanwhile, the electric properties of copper films are investigated, which confirms that copper films are conductive. A tentative mechanism of the selective deposition process is also proposed. In addition, the potential application of this technique for integrating electrical and thermal functions into microdevices is discussed.

  14. PREPARATION OF MICROWAVE ABSORBING NICKEL-BASED ACTIVATED CARBON BY ELECTROLESS PLATING WITH PALLADIUM-FREE ACTIVATION

    OpenAIRE

    Boyang Jia; Lijuan Wang

    2010-01-01

    Nickel-based activated carbon was prepared from coconut shell activated carbon by electroless plating with palladium-free activation. The materials were characterized by scanning electron microscopy (SEM), X-ray energy dispersion spectroscopy (EDS), vibrating sample magnetometry (VSM), and vector network analyzer, respectively. The results show that the surface of the activated carbon was covered by a Ni-P coating, which was uniform, compact, and continuous and had an obvious metallic sheen. ...

  15. The Microstructure and Thermal Conductivity of Pressureless Infiltrated SiCp/Al Composites Containing Electroless Nickel Platings

    OpenAIRE

    Aihua Zou; Xianliang Zhou; Xiaozhen Hua; Duosheng Li; Kaiyang Wu

    2015-01-01

    A nickel (Ni) coating was deposited on the surface of silicon carbide particles (SiCp) through electroless plating and we characterized the morphology and phase structure of the coating and the pressureless infiltrated SiCp/Al composites. The effect of Ni coatings on the thermal conductivity of the composites was examined and analyzed with three-dimensional video microscope, scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction microscope (XRD), and...

  16. Wire-bonding on inkjet-printed silver pads reinforced by electroless plating for chip on flexible board packages

    OpenAIRE

    Cauchois, Romain; Saadaoui, Mohamed; Legeleux, Jacques; Malia, Thierry; Dubois-Bonvalot, Béatrice; Inal, Karim; Fidalgo, Jean-Christophe

    2010-01-01

    The nanoporous nature of the inkjet printed silver nanoparticles entail low hardness and surface effective contact area for being compatible with pads that are suitable for wire-bonding in electronic packaging. Electroless nickel plating is a selective metal deposition technique which can brings the required thickness and hardness for further pads processing. Here, a 1.7 μm thick nickel layer is deposited on top of 600 nm thick printed and sintered silver nanoparticles using Kapton polyimide ...

  17. A fine surface roughness electroless Ni–P–PTFE composite modified stamper for light guide plate application

    International Nuclear Information System (INIS)

    Electroless Ni–P–PTFE composite coating technology takes advantage of the beneficial properties from both Ni–P alloy and PTFE, such as good wear resistance, good anti-adhesion, dry lubrication, low coefficient of friction and good corrosion resistance. It has been applied in many mold industries. However, the Ni–P–PTFE composite coating suffers from bad surface roughness, when the PTFE particles incorporate into a Ni–P matrix. This severely hampers the technology to be applied to optical grade applications. In this paper, we propose a trick to generate a fine surface roughness (FSR) electroless Ni–P–PTFE composite to modify a nickel stamper. Using this new method, the nickel stamper can be covered by a Ni–P–PTFE functional layer and can keep the original surface property at the same time, namely the optical properties. We have chosen 4.5 inch (97 mm × 59 mm × 0.6 mm) light guide plates (LGPs) to demonstrate the effectiveness of the procedure. For the sake of comparison, the LGPs were produced by injection molding with three kinds of stampers including an original SUS430 master, an electroless Ni–P–PTFE composite coated nickel stamper and an FSR electroless Ni–P–PTFE composite modified stamper. We measured and discussed the optical performances at both the element level and system level, namely complete back light units.

  18. Electroless plating of copper on polyimide films modified by surface-initiated atom-transfer radical polymerization of 4-vinylpyridine

    International Nuclear Information System (INIS)

    Surface modification of polyimide (PI) films were first carried out by chloromethylation under mild conditions, followed by surface-initiated atom-transfer radical polymerization (ATRP) of 4-vinylpyridine (4VP) from the chloromethylated PI surfaces. The composition and topography of the PI surfaces modified by poly(4-vinylpyridine) (P4VP) were characterized by X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM), respectively. The P4VP brushes with well-preserved pyridine groups on the PI surface was used not only as the chemisorption sites for the palladium complexes without prior sensitization by SnCl2 solution during the electroless plating of copper, but also as an adhesion promotion layer to enhance the adhesion of the electrolessly deposited copper to the PI surfaces. The T-peel adhesion strength of the electrolessly deposited copper on the modified PI surface could reach about 6.6 N/cm. Effects of the polymerization time and the activation time in the PdCl2 solution on the T-peel adhesion strength of the electrolessly deposited copper in the Sn-free process to the modified PI surface were also studied

  19. Corrosion and wear properties of electroless Ni-P plating layer on AZ91D magnesium alloy

    Institute of Scientific and Technical Information of China (English)

    LI Zhong-hou; CHEN Zhi-yong; LIU Sha-sha; ZHENG Feng; DAI A-gan

    2008-01-01

    A direct electroless Ni-P plating treatment was applied to AZ91D magnesium alloy for improving its corrosion resistance and wear resistance. Corrosion resistance of the Ni-P coatings was evaluated by potentiodynamic polarization and immersing experiments in 3.5% NaCl solution. The wear resistance of the coatings was investigated by the wear track and the mass change after ball-on-disk experiment. The results show that corrosion resistance and wear resistance of the AZ91D alloy are greatly improved after direct electroless Ni-P plating. No discoloration is noticed until 4 d of immersion in 3.5% NaCl solution. Potentiodynamic polarization experiments show that the free corrosion potential of magnesium alloy is shifted from -1 500 mV to -250 mV and passivation occurs at 1 350 mV after direct electroless plating. The friction coefficients and wear rates of Ni-P coating and Ni-P coating after tempering are 0.10-0.351, 9.038×10-3 mm3/m and 0.13-0.177, 3.056×10-4 mm3/m, respectively, at a load of 1.5 N with dry sliding. Although minor hurt on corrosion resistance was caused, significant improvement of wear resistance was obtained after tempering treatment of the coating.

  20. Characterization and Properties of Electroless Nickel Plated Poly (ethylene terephthalate) Nonwoven Fabric Enhanced by Dielectric Barrier Discharge Plasma Pretreatment

    Science.gov (United States)

    Geng, Yamin; Lu, Canhui; Liang, Mei; Zhang, Wei

    2010-12-01

    In order to develop a more economical pretreatment method for electroless nickel plating, a dielectric barrier discharge (DBD) plasma at atmospheric pressure was used to improve the hydrophilicity and adhesion of poly (ethylene terephthalate) (PET) nonwoven fabric. The properties of the PET nonwoven fabric including its liquid absorptive capacity (WA), aging behavior, surface chemical composition, morphology of the surface, adhesion strength, surface electrical resistivity and electromagnetic interference (EMI)- shielding effectiveness (SE) were studied. The liquid absorptive capacity (WA) increased due to the incorporation of oxygen-containing and nitrogen-containing functional groups on the surface of PET nonwoven fabric after DBD air-plasma treatment. The surface morphology of the nonwoven fibers became rougher after plasma treatment. Therefore, the surface was more prone to absorb tin sensitizer and palladium catalyst to form an active layer for the deposition of electroless nickel. SEM and X-ray diffraction (XRD) measurements indicated that a uniform coating of nickel was formed on the PET nonwoven fabric. The average EMI-SE of Ni-plating of PET nonwoven fabric maintained a relatively stable value (38.2 dB to 37.3 dB) in a frequency range of 50 MHz to 1500 MHz. It is concluded that DBD is feasible for pretreatment of nonwoven fabric for electroless nickel plating to prepare functional material with good EMI-SE properties.

  1. Characterization and Properties of Electroless Nickel Plated Poly (ethylene terephthalate) Nonwoven Fabric Enhanced by Dielectric Barrier Discharge Plasma Pretreatment

    International Nuclear Information System (INIS)

    In order to develop a more economical pretreatment method for electroless nickel plating, a dielectric barrier discharge (DBD) plasma at atmospheric pressure was used to improve the hydrophilicity and adhesion of poly (ethylene terephthalate) (PET) nonwoven fabric. The properties of the PET nonwoven fabric including its liquid absorptive capacity (WA), aging behavior, surface chemical composition, morphology of the surface, adhesion strength, surface electrical resistivity and electromagnetic interference (EMI)- shielding effectiveness (SE) were studied. The liquid absorptive capacity (WA) increased due to the incorporation of oxygen-containing and nitrogen-containing functional groups on the surface of PET nonwoven fabric after DBD air-plasma treatment. The surface morphology of the nonwoven fibers became rougher after plasma treatment. Therefore, the surface was more prone to absorb tin sensitizer and palladium catalyst to form an active layer for the deposition of electroless nickel. SEM and X-ray diffraction (XRD) measurements indicated that a uniform coating of nickel was formed on the PET nonwoven fabric. The average EMI-SE of Ni-plating of PET nonwoven fabric maintained a relatively stable value (38.2 dB to 37.3 dB) in a frequency range of 50 MHz to 1500 MHz. It is concluded that DBD is feasible for pretreatment of nonwoven fabric for electroless nickel plating to prepare functional material with good EMI-SE properties.

  2. Copper-Ti3SiC2 composite powder prepared by electroless plating under ultrasonic environment

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhongbao; XU Shaofan

    2007-01-01

    In this article, a new type of Cu-Ti3SiC2 composite powder prepared using the electroless plating technique was introduced. The initial Ti3SiC2 particles are 11 μm in diameter on an average. The Cu plating was carried out at middle temperature (62-65 ℃) with the application of ultrasonic agitation. The copper deposition rate was determined by measuring the weight gain of the powder after plating. It has been found that the pretreatment of Ti3SiC2 powder is very important to obtain copper nanoparticles on the surface of Ti3SiC2. The optimum procedure before plating aimed to add activated sites and the adjustment of the tradifonal composition of the electroless copper plating bath could decelerate the copper deposition rate to 0.8 μm/h. X-ray diffraction (XRD) indicates that the chemical composition of the plating layer is copper. SEM images show that the surface of the Ti3SiC2 particles is successfully coated with continuous copper layer. The wetting property between the copper matrix and Ti3SiC2 can be improved so as to increase the interfacial strength.

  3. 镁合金化学镀镍层的生长过程%Deposition process of electroless nickel plating on magnesium alloy

    Institute of Scientific and Technical Information of China (English)

    邵忠财; 李建中; 康凤娣; 田彦文

    2005-01-01

    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.

  4. Electrical resistivity and dielectric properties of helical microorganism cells coated with silver by electroless plating

    International Nuclear Information System (INIS)

    Highlights: ► We use the microorganism cells as forming templates to fabricate the bio-based conductive particles. ► The microorganism cells selected as forming templates are Spirulina platens, which are of natural helical shape and high aspect ratio. ► The sliver-coated Spirulina cells are a kind of lightweight conductive particles. ► The composites containing sliver-coated Spirulina cells exhibit a lower percolation value. - Abstract: In this paper, microorganism cells (Spirulina platens) were used as forming templates for the fabrication of the helical functional particles by electroless silver plating process. The morphologies and ingredients of the coated Spirulina cells were analyzed with scanning electron microscopy and energy dispersive spectrometer. The crystal structures were characterized by employing the X-ray diffraction. The electrical resistivity and dielectric properties of samples containing different volume faction of sliver-coated Spirulina cells were measured and investigated by four-probe meter and vector network analyzer. The results showed that the Spirulina cells were successfully coated with a uniform silver coating and their initial helical shapes were perfectly kept. The electrical resistivity and dielectric properties of the samples had a strong dependence on the volume content of sliver-coated Spirulina cells and the samples could achieve a low percolation value owing to high aspect ratio and preferable helical shape of Spirulina cells. Furthermore, the conductive mechanism was analyzed with the classic percolation theory, and the values of φc and t were obtained.

  5. Reclaim nickel and remove organics from the spent electroless nickel-plating bath by electrolysis

    Institute of Scientific and Technical Information of China (English)

    YU Xiu-juan; SHEN Jin; MENG Xian-lin; LI Shu-qin; YAN Lei; ZHOU Ding

    2006-01-01

    Typical wastes from nickel plating operations include excess drag-out solution. An electrochemical approach was made to recover the nickel and remove the organic pollutants from the spent electroless nickelplating bath. An electrolyte cell which was constructed by the cathode of porous nickel foam and the anode of Ti/RuO2 was used. During electrolysis, the nickel ion was electrodeposited at the cathode and the oxidation of the organics in the bath was conducted at the anode. The current ( i), time ( t), temperature (T) and pH of the solution affected the recovery efficiency of nickel with constant potential electrolysis. With the optimum experimental conditions of pH = 7. 6, i = 0.45 A, T = 65℃ and t = 2 h, the concentration of nickel ion was reduced from 2. 09 g/L to 0. 053 g/L and the recovery rate of nickel, the current efficiency and the consumed energy were 97.5%, 17.1%, 12.2 kWh/kg Ni, respectively. Meanwhile, total organic carbon (TOC) of the bath was reduced from 5 800 mg/L to 152. 5 mg/L and the removal efficiency of TOC was 97.3%. The recovery rate of nickel could keep to about 97% when electrodeposit was used to recover nickel for 40 hours in a laboratory batch reactor containing the spent bath. Dull nickel containing phosphorus was obtained on the cathode.

  6. Preparation and microwave properties of Ni hollow fiber by electroless plating-template method

    International Nuclear Information System (INIS)

    Nickel-coated silk composites (Ni/silk fiber) were prepared by electroless nickel-plating using a kind of natural silk as template in first stage. The silk templates were then removed to get Ni hollow fiber by annealing the Ni/silk fiber at 220 deg. C for 2 h in air or 700 deg. C for 1.5 h in nitrogen. The prepared Ni/silk fiber and Ni hollow fiber were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), field emission scanning electron microscope (FE-SEM) and differential thermal analysis and thermogravimetric analysis (TG-DTA). The values of complex permittivity, complex permeability, dielectric and magnetic loss of Ni/silk fiber and Ni hollow fiber were measured in the frequency range of 2-18 GHz by a reflection/transmission approach using a network analyzer. The results indicate that the dielectric loss of Ni/silk fiber and Ni hollow fiber is high up to 1 even at 18 GHz while the magnetic loss is low

  7. Electroless plating of ultrathin palladium films: self-initiated deposition and application in microreactor fabrication

    Science.gov (United States)

    Muench, Falk; Oezaslan, Mehtap; Svoboda, Ingrid; Ensinger, Wolfgang

    2015-10-01

    We present new electroless palladium plating reactions, which can be applied to complex-shaped substrates and lead to homogeneous, dense and conformal palladium films consisting of small nanoparticles. Notably, autocatalytic and surface-selective metal deposition could be achieved on a wide range of materials without sensitization and activation pretreatments. This provides a facile and competitive route to directly deposit well-defined palladium nanofilms on e.g. carbon, paper, polymers or glass substrates. The reactions proceed at mild conditions and are based on easily accessible chemicals (reducing agent: hydrazine; metal source: PdCl2; ligands: ethylenediaminetetraacetic acid (EDTA), acetylacetone). Additionally, the water-soluble capping agent 4-dimethylaminopyridine (DMAP) is employed to increase the bath stability, to ensure the formation of small particles and to improve the film conformity. The great potential of the outlined reactions for micro- and nanofabrication is demonstrated by coating an ion-track etched polycarbonate membrane with a uniform Pd film of approximately 20 nm thickness. The as-prepared membrane is then employed as a highly miniaturized flow reactor, using the reduction of 4-nitrophenol with NaBH4 as a model reaction.

  8. Preparation, characterization and wear behavior of carbon coated magnesium alloy with electroless plating nickel interlayer

    Energy Technology Data Exchange (ETDEWEB)

    Mao, Yan [Shanghai Key Laboratory of Materials Laser Processing and Modification, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Li, Zhuguo, E-mail: lizg@sjtu.edu.cn [Shanghai Key Laboratory of Materials Laser Processing and Modification, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Academician Expert Office Workstation (Jiansheng Pan), Lin’an, Zhejiang Province (China); Feng, Kai, E-mail: fengkai@sjtu.edu.cn [Shanghai Key Laboratory of Materials Laser Processing and Modification, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Academician Expert Office Workstation (Jiansheng Pan), Lin’an, Zhejiang Province (China); Guo, Xingwu [National Engineering Research Center of Light Alloys Net Forming (LAF), School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Zhou, Zhifeng [Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Kowloon, Hong Kong (China); Dong, Jie [National Engineering Research Center of Light Alloys Net Forming (LAF), School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Wu, Yixiong [Shanghai Key Laboratory of Materials Laser Processing and Modification, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai 200240 (China); Academician Expert Office Workstation (Jiansheng Pan), Lin’an, Zhejiang Province (China)

    2015-02-01

    Highlights: • The carbon film with nickel interlayer (Ni + C coating) is deposited on GW83. • In Ni + C composite coating the carbon coating has good adhesion with the nickel interlayer. • The wear track of Ni + C coating is narrower compared to the bare one. • The wear resistance of GW83 is greatly improved by the Ni + C coating. - Abstract: Poor wear resistance of rare earth magnesium alloys has prevented them from wider application. In this study, composite coating (PVD carbon coating deposited on electroless plating nickel interlayer) is prepared to protect GW83 magnesium alloys against wear. The Ni + C composite coating has a dense microstructure, improved adhesion strength and hardness due to the effective support of Ni interlayer. The wear test result shows that the Ni + C composite coating can greatly prolong the wear life of the magnesium alloy. The wear track of the Ni + C coated magnesium alloy is obviously narrower and shows less abrasive particles as compared with the bare one. Abrasive wear is the wear mechanism of the coatings at the room temperature. In conclusion, the wear resistance of the GW83 magnesium alloy can be greatly improved by the Ni + C composite coating.

  9. Electroless plating preparation and electromagnetic properties of Co-coated carbonyl iron particles/polyimide composite

    Science.gov (United States)

    Zhou, Yingying; Zhou, Wancheng; Li, Rong; Qing, Yuchang; Luo, Fa; Zhu, Dongmei

    2016-03-01

    To solve the serious electromagnetic interference problems at elevated temperature, one thin microwave-absorbing sheet employing Co-coated carbonyl iron particles and polyimide was prepared. The Co-coated carbonyl iron particles were successfully prepared using an electroless plating method. The microstructure, composition, phase and static magnetic properties of Co-coated carbonyl iron particles were characterized by combination of scanning electron microscope (SEM), energy dispersive spectrometer (EDS), X-ray diffraction (XRD) and vibrating sample magnetometer (VSM). The electromagnetic parameters of Co-coated carbonyl iron particles/polyimide composite were measured in the frequency range of 2-18 GHz, and the electromagnetic loss mechanism of the material-obtained was discussed. The microwave absorption properties of composites before and after heat treatment at 300 °C for 100 h were characterized in 2-18 GHz frequency range. It was established that composites based on Co-coated carbonyl iron demonstrate thermomagnetic stability, indicating that Co coating reduces the oxidation of carbonyl iron. Thus, Co-coated carbonyl iron particles/polyimide composites are useful in the design of microwave absorbers operating at temperatures up to 300 °C.

  10. Processing of aluminum matrix composites by electroless plating and melt infiltration

    International Nuclear Information System (INIS)

    Reduction of the SiC/ Al interaction and enhancement of wetting between reinforcements and molten aluminum was obtained by modifying the ceramic surface with deposition of nickel and copper coatings. The preparation of nickel- and copper-coated ceramic particles as precursors for MMC fabrication was studied. Al2O3 and SiC powders were successfully coated with Ni and Cu using electroless metal plating. Uniform and continuous metal films were deposited on both, alumina and silicon carbide powders XRD showed that the Ni-P deposit was predominantly amorphous, while the copper deposit was essentially polycrystalline. Infiltration results showed that the use of the coated powders enhances the wettability between the matrix and ceramic phase when processing particulate MMCs by a vacuum infiltration technique, giving a porosity-free composite with a homogeneously distributed reinforcing phase. The coating promoted easy metal flow through the preform, compared to the non-infiltration behavior of the uncoated counterpart samples XRD microstructural analysis of the composites indicates the formation of intermetallic phases such as CuAl2, in the case of copper coating, and NiAl and NiAl3 when nickel-coated powders are infiltrated. Metallization of the ceramics minimizes the interfacial reaction of the SiC/Al composites and promotes wetting of Al2O3 reinforcements with liquid aluminum. Copyright (2000) AD-TECH - International Foundation for the Advancement of Technology Ltd

  11. Fabrication and microwave properties of hollow nickel spheres prepared by electroless plating and template corrosion method

    International Nuclear Information System (INIS)

    Using carbonyl iron as template, hollow nickel spheres were prepared by electroless plating on carbonyl iron and template corrosion method. The samples were characterized by X-ray diffraction (XRD), X-ray fluorescence spectrometer (XRF), transmission electron microscope (TEM), scanning electron microscope (SEM), vibrating sample magnetometer (VSM) and vector network analyzer. Results showed that the shell thickness can be controlled by adjusting the loadage of carbonyl iron templates. The hollow nickel spheres exhibited good magnetic properties with a saturation magnetization of 48.56 emu/g and enhanced coercivity (as high as 260 Oe). The real (ε′) and imaginary (ε″) parts of complex permittivity of hollow nickel spheres first increased and then decreased as the shell thickness increased, and the sample with the thinnest shell showed the lowest complex permittivity. For the complex permeability, the resonance peak shifted to the lower frequency and then moved to higher frequency, as the shell thickness increased. The microwave absorption performances could be tuned by changing the shell thickness. In this study, the minimum reflection loss (RL) value of −27.2 dB was obtained at 13.4 GHz with a matching thickness of 1.4 mm and the effective absorption band (RL <−5 dB) from 11.8 to 18 GHz, covering the whole Ku-band (12.4−18 GHz).

  12. Microwire formation based on dielectrophoresis of electroless gold plated polystyrene microspheres

    International Nuclear Information System (INIS)

    Microspheres coated with a perfectly conductive surface have many advantages in the applications of biosensors and micro-electromechanical systems. Polystyrene microspheres with the diameter of 10 μm were coated with a 50 nm-thick gold layer using an electroless gold plating approach. Dielectrophoresis (DEP) for bare microspheres and shelled microspheres was theoretically analysed and the real part of the Clausius—Mossotti factor was calculated for the two kinds of microspheres. The experiments on the dielectrophoretic characterisation of the uncoated polystyrene microspheres and gold coated polystyrene microspheres (GCPMs) were carried out. Experimental results showed that the gold coated polystyrene microspheres were only acted by a positive dielectrophoretic force when the frequency was below 40M Hz, while the uncoated polystyrene microspheres were governed by a negative dielectrophoretic force in this frequency range. The gold coated polystyrene microspheres were exploited to form the microwire automatically according to their stable dielectrophoretic and electric characterisations. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  13. Preparation, characterization and wear behavior of carbon coated magnesium alloy with electroless plating nickel interlayer

    International Nuclear Information System (INIS)

    Highlights: • The carbon film with nickel interlayer (Ni + C coating) is deposited on GW83. • In Ni + C composite coating the carbon coating has good adhesion with the nickel interlayer. • The wear track of Ni + C coating is narrower compared to the bare one. • The wear resistance of GW83 is greatly improved by the Ni + C coating. - Abstract: Poor wear resistance of rare earth magnesium alloys has prevented them from wider application. In this study, composite coating (PVD carbon coating deposited on electroless plating nickel interlayer) is prepared to protect GW83 magnesium alloys against wear. The Ni + C composite coating has a dense microstructure, improved adhesion strength and hardness due to the effective support of Ni interlayer. The wear test result shows that the Ni + C composite coating can greatly prolong the wear life of the magnesium alloy. The wear track of the Ni + C coated magnesium alloy is obviously narrower and shows less abrasive particles as compared with the bare one. Abrasive wear is the wear mechanism of the coatings at the room temperature. In conclusion, the wear resistance of the GW83 magnesium alloy can be greatly improved by the Ni + C composite coating

  14. Electrical resistivity and dielectric properties of helical microorganism cells coated with silver by electroless plating

    Science.gov (United States)

    Cai, Jun; Lan, Mingming; Zhang, Deyuan; Zhang, Wenqiang

    2012-09-01

    In this paper, microorganism cells (Spirulina platens) were used as forming templates for the fabrication of the helical functional particles by electroless silver plating process. The morphologies and ingredients of the coated Spirulina cells were analyzed with scanning electron microscopy and energy dispersive spectrometer. The crystal structures were characterized by employing the X-ray diffraction. The electrical resistivity and dielectric properties of samples containing different volume faction of sliver-coated Spirulina cells were measured and investigated by four-probe meter and vector network analyzer. The results showed that the Spirulina cells were successfully coated with a uniform silver coating and their initial helical shapes were perfectly kept. The electrical resistivity and dielectric properties of the samples had a strong dependence on the volume content of sliver-coated Spirulina cells and the samples could achieve a low percolation value owing to high aspect ratio and preferable helical shape of Spirulina cells. Furthermore, the conductive mechanism was analyzed with the classic percolation theory, and the values of ϕ and t were obtained.

  15. A polydopamine-modified optical fiber SPR biosensor using electroless-plated gold films for immunoassays.

    Science.gov (United States)

    Shi, Se; Wang, Libing; Su, Rongxin; Liu, Boshi; Huang, Renliang; Qi, Wei; He, Zhimin

    2015-12-15

    A sensitive and stable electroless-plated gold film for the preparation of an optical fiber surface plasmon resonance (SPR) sensor is presented in this work, together with a facile antibody immobilization method. Gold nanoparticles were uniformly adsorbed onto the surface of an optical fiber forming a film with a thickness of approximately 56.3 nm. The sensor had a high sensitivity with 2054 nm/RIU and 3980 nm/RIU in the refractive index ranges of 1.333-1.359 and 1.359-1.386, respectively. An SPR biosensor was developed based on polydopamine-modified gold film (PDA-Au), which was fabricated by a simple and quick spontaneous polymerization of dopamine (DA) on the gold film. When goat anti-human IgG antibodies were immobilized, the PDA-Au surface had a larger resonant wavelength shift of 66.21 nm compared with the traditional 11-mercaptoundecanoic acid-modified gold film (MUA-Au) surface. In addition, the PDA-Au surface enabled the sensitive and selective determination of human IgG down to a concentration of 2 μg mL(-1) with a high sensitivity of 0.41 nm per μg mL(-1). The PDA-Au surface exhibited an approximately four fold higher sensitivity and an about seven fold lower LOD than the MUA-Au surface to human IgG. PMID:26164491

  16. Structural Characterization and Mechanical Properties of As-plated and Heat Treated Electroless Ni-B-P Alloy Coatings

    OpenAIRE

    P. G. Venkatakrishnan; S. S. Mohamed Nazirudeen; T.S.N. Sankara Narayanan

    2014-01-01

    The Ni-B-P alloy coatings were made autocatalytically (electroless) using an alkaline plating bath with nickel chloride hexahydrate (NiCl2.6H2O) as the source of nickel ions, sodium borohydride (NaBH4) and sodium hypophosphite (NaH2PO2) as reducing agents and source of boron and phosphorous ions, respectively. The effects of bath concentrations on the plating rate, composition of coating, surface morphology, structural features and microhardness have been studied by varying NaBH4 concentra...

  17. Region-selective electroless gold plating on polycarbonate sheets by UV-patterning in combination with silver activating

    International Nuclear Information System (INIS)

    A simple, time- and cost-effective approach for region-selective metalization of polycarbonate (PC) surface has been established by combining photoresist-free UV-patterning with tin- and amine-free silver activating and electroless gold plating. The surface of PC sheets was exposed to the UV lights emitted from a low-pressure mercury lamp through a photomask, the micro pattern on the mask being transferred to the PC surface due to the photochemical generation of carboxyl groups on the UV-exposed region. The UV-exposed PC sheets were then treated with an ammoniacal AgNO3 solution, so that the silver ions were chemisorbed by the photochemically generated carboxyl groups. When the Ag+-adsorbed PC sheet was immersed into an electroless gold plating bath, shiny gold film quickly deposited on the UV-exposed region, resulting in the formation of a micro gold devices on the PC surface. The whole plating process including UV-exposure, surface activating and gold plating can be completed in about 3-4 h. Attenuated total reflection Fourier transformation infrared spectrometer (ATR-FT-IR), X-ray photoelectron spectroscopy (XPS), atomic force microscope (AFM) and scanning electron microscope (SEM) were employed to trace the surface change during the plating process. Cyclic voltammetry (CV) and Scotch-tape test were employed to characterize the electrochemical properties and adhesion strength of the prepared micro gold devices, respectively. The prepared micro gold electrodes were demonstrated for amperometric detection of hydrogen peroxide.

  18. Region-selective electroless gold plating on polycarbonate sheets by UV-patterning in combination with silver activating

    Energy Technology Data Exchange (ETDEWEB)

    Zhou Qinghua [Institute of Microanalytical Systems, Department of Chemistry, Zhejiang University, Zijin' gang Campus, Hangzhou 310058 (China); Chen Hengwu, E-mail: hwchen@zju.edu.c [Institute of Microanalytical Systems, Department of Chemistry, Zhejiang University, Zijin' gang Campus, Hangzhou 310058 (China); Wang Yi [Institute of Microanalytical Systems, Department of Chemistry, Zhejiang University, Zijin' gang Campus, Hangzhou 310058 (China)

    2010-02-28

    A simple, time- and cost-effective approach for region-selective metalization of polycarbonate (PC) surface has been established by combining photoresist-free UV-patterning with tin- and amine-free silver activating and electroless gold plating. The surface of PC sheets was exposed to the UV lights emitted from a low-pressure mercury lamp through a photomask, the micro pattern on the mask being transferred to the PC surface due to the photochemical generation of carboxyl groups on the UV-exposed region. The UV-exposed PC sheets were then treated with an ammoniacal AgNO{sub 3} solution, so that the silver ions were chemisorbed by the photochemically generated carboxyl groups. When the Ag{sup +}-adsorbed PC sheet was immersed into an electroless gold plating bath, shiny gold film quickly deposited on the UV-exposed region, resulting in the formation of a micro gold devices on the PC surface. The whole plating process including UV-exposure, surface activating and gold plating can be completed in about 3-4 h. Attenuated total reflection Fourier transformation infrared spectrometer (ATR-FT-IR), X-ray photoelectron spectroscopy (XPS), atomic force microscope (AFM) and scanning electron microscope (SEM) were employed to trace the surface change during the plating process. Cyclic voltammetry (CV) and Scotch-tape test were employed to characterize the electrochemical properties and adhesion strength of the prepared micro gold devices, respectively. The prepared micro gold electrodes were demonstrated for amperometric detection of hydrogen peroxide.

  19. Reliability Tests of Aluminium Wedge Wire Bonding on Auto-catalytic Silver Immersion Gold (ASIG) PCB Metallization

    CERN Document Server

    Drozd, A; Kaufmann, S; Manolescu, F; McGill, I

    2011-01-01

    The Auto-catalytic Silver Immersion Gold (ASIG) PCB metallization is a new process that has clear advantages for PCB assembly especially with regard to lead-free soldering. As it may become a popular process in the future for electronics used in physics experiments, the quality of this metallization for aluminium wire bonding has been studied. Aluminium wedge wire bonding continues to be the interconnection method of choice for many physics detector sensors, for high density signal routing and for unpackaged die. Although advertised as having good quality for aluminium wire bonding, this study was performed to verify this claim as well as to test the longer term reliability of the wire bonds taking into consideration the environmental conditions and life-expectancy of devices, in particular for high energy physics detector applications. The tests were performed on PCBs made with the ASIG and ENIG (Electro-less Nickel Immersion Gold) processes at the same time in order to make a comparison with the current ind...

  20. Structural Characterization and Mechanical Properties of As-plated and Heat Treated Electroless Ni-B-P Alloy Coatings

    Directory of Open Access Journals (Sweden)

    P. G. Venkatakrishnan

    2014-05-01

    Full Text Available The Ni-B-P alloy coatings were made autocatalytically (electroless using an alkaline plating bath with nickel chloride hexahydrate (NiCl2.6H2O as the source of nickel ions, sodium borohydride (NaBH4 and sodium hypophosphite (NaH2PO2 as reducing agents and source of boron and phosphorous ions, respectively. The effects of bath concentrations on the plating rate, composition of coating, surface morphology, structural features and microhardness have been studied by varying NaBH4 concentration in the plating bath from 0.2 to 0.8 g/l while keeping NaH2PO2 concentration constant (12 g/l. The plating rate and boron content of the electroless Ni-B-P ternary alloy coatings increased with increasing NaBH4 concentration in the plating bath. The scanning electron microscopic images revealed that the morphology of the coating changed from corn cob structure to coarse cauliflower structure with increasing borohydride concentration in the plating bath. Broadening of X-ray diffraction peak is observed, as the borohydride concentration is increased in the plating bath, which is attributed to the large reduction in the crystallite size of the Ni-B-P alloy coatings. The microhardness values of the coating increased with increasing borohydride concentration in the plating bath. The as-plated Ni-B-P alloy coating containing higher boron content (3.2 wt% shows higher hardness of 700 HV compared to other Ni-B-P alloy coatings. The XRD patterns of heat treated Ni-B-P alloy coatings (500 °C show Ni3B intermetallic peaks along with Ni peaks. The presence of Ni3B intermetallic compound significantly increases the microhardness values of the heat treated Ni-B-P alloy coatings.

  1. Fabrication of a metal membrane on a perforated polymer substrate by palladium aerosol activation and subsequent electroless plating.

    Science.gov (United States)

    Byeon, Jeong Hoon; Hwang, Jungho

    2009-02-01

    Fabrication of a metal membrane on a perforated flexible poly(tetrafluoroethylene) (PTFE) substrate was developed by employing spark-generated palladium (Pd) aerosol activation and the subsequent electroless plating of Pd. After aerosol activation, Pd agglomerates of spark-generated primary particles (approximately 2.6 nm in diameter) with a face-centered-cubic structure were deposited uniformly on the PTFE substrate. Homogeneous Pd particles with an average size of 188 nm were tightly packed together to form a Pd membrane after Pd plating. The average plating rate of Pd during 30 min of plating at an activation intensity of 25 microg/cm(2) was 14.2 microg/cm(2) x min. PMID:20353212

  2. Electrical resistivity and dielectric properties of helical microorganism cells coated with silver by electroless plating

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Jun, E-mail: jun_cai@buaa.edu.cn [Bionic and Micro/Nano/Bio Manufacturing Technology Research Center, School of Mechanical Engineering and Automation, Beihang University, Beijing 100191 (China); Lan, Mingming; Zhang, Deyuan; Zhang, Wenqiang [Bionic and Micro/Nano/Bio Manufacturing Technology Research Center, School of Mechanical Engineering and Automation, Beihang University, Beijing 100191 (China)

    2012-09-01

    Highlights: Black-Right-Pointing-Pointer We use the microorganism cells as forming templates to fabricate the bio-based conductive particles. Black-Right-Pointing-Pointer The microorganism cells selected as forming templates are Spirulina platens, which are of natural helical shape and high aspect ratio. Black-Right-Pointing-Pointer The sliver-coated Spirulina cells are a kind of lightweight conductive particles. Black-Right-Pointing-Pointer The composites containing sliver-coated Spirulina cells exhibit a lower percolation value. - Abstract: In this paper, microorganism cells (Spirulina platens) were used as forming templates for the fabrication of the helical functional particles by electroless silver plating process. The morphologies and ingredients of the coated Spirulina cells were analyzed with scanning electron microscopy and energy dispersive spectrometer. The crystal structures were characterized by employing the X-ray diffraction. The electrical resistivity and dielectric properties of samples containing different volume faction of sliver-coated Spirulina cells were measured and investigated by four-probe meter and vector network analyzer. The results showed that the Spirulina cells were successfully coated with a uniform silver coating and their initial helical shapes were perfectly kept. The electrical resistivity and dielectric properties of the samples had a strong dependence on the volume content of sliver-coated Spirulina cells and the samples could achieve a low percolation value owing to high aspect ratio and preferable helical shape of Spirulina cells. Furthermore, the conductive mechanism was analyzed with the classic percolation theory, and the values of {phi}{sub c} and t were obtained.

  3. Development of Microelectrode Arrays Using Electroless Plating for CMOS-Based Direct Counting of Bacterial and HeLa Cells.

    Science.gov (United States)

    Niitsu, Kiichi; Ota, Shoko; Gamo, Kohei; Kondo, Hiroki; Hori, Masaru; Nakazato, Kazuo

    2015-10-01

    The development of two new types of high-density, electroless plated microelectrode arrays for CMOS-based high-sensitivity direct bacteria and HeLa cell counting are presented. For emerging high-sensitivity direct pathogen counting, two technical challenges must be addressed. One is the formation of a bacteria-sized microelectrode, and the other is the development of a high-sensitivity and high-speed amperometry circuit. The requirement for microelectrode formation is that the gold microelectrodes are required to be as small as the target cell. By improving a self-aligned electroless plating technique, the dimensions of the microelectrodes on a CMOS sensor chip in this work were successfully reduced to 1.2 μm × 2.05 μm. This is 1/20th of the smallest size reported in the literature. Since a bacteria-sized microelectrode has a severe limitation on the current flow, the amperometry circuit has to have a high sensitivity and high speed with low noise. In this work, a current buffer was inserted to mitigate the potential fluctuation. Three test chips were fabricated using a 0.6- μm CMOS process: two with 1.2 μm × 2.05 μm (1024 × 1024 and 4 × 4) sensor arrays and one with 6- μm square (16 × 16) sensor arrays; and the microelectrodes were formed on them using electroless plating. The uniformity among the 1024 × 1024 electrodes arranged with a pitch of 3.6 μm × 4.45 μm was optically verified. For improving sensitivity, the trenches on each microelectrode were developed and verified optically and electrochemically for the first time. Higher sensitivity can be achieved by introducing a trench structure than by using a conventional microelectrode formed by contact photolithography. Cyclic voltammetry (CV) measurements obtained using the 1.2 μm × 2.05 μm 4 × 4 and 6- μm square 16 × 16 sensor array with electroless-plated microelectrodes successfully demonstrated direct counting of the bacteria-sized microbeads and HeLa cells. PMID:26561481

  4. Preparation and Magnetic Properties of Anisotropic (Sm,Pr)Co5/Fe Nanocomposites Particles via Electroless Plating

    OpenAIRE

    Shi Wang; Jin-Ming Ma; Yan Chen

    2014-01-01

    Anisotropic (Sm,Pr)Co5/Fe nanocomposites particles were prepared by electroless plating iron on the surface of (Sm,Pr)Co5 nanoflakes after being prepared by ball milling for 4 h. A uniform and continuous coating layer was obtained due to the addition of complexing agent and the particle size of the reduced Fe particles was in the range of 10~20 nm. When the nominal addition of Fe was 15 wt%, the nanocomposites show enhanced remnant and saturation magnetization: Mr=53.35 emu/g, Ms=73.08 emu/g ...

  5. Selective deposition on electrodes of chip component by electroless plating method

    Science.gov (United States)

    Yamamoto, Akihiro; Watanabe, Nobuaki; Arakawa, Tomiyuki; Gotou, Miku; Nakada, Tatsunosuke; Fukui, Kenta; Hashimoto, Akira; Koiwa, Ichiro

    2014-05-01

    The selective electroless deposition on metallic electrodes of a micro-passive-chip component was investigated. We performed three pretreatments: (a) alkaline degreasing, (b) acid activation, and (c) catalytic activation by the double alternate-dipping method consisting of two steps, i.e., sensitization (SnCl2) and activation (PdCl2). Catalytic conditions such as the concentration of PdCl2, activation time, and number of activation times were optimized to achieve the selectivity of electroless deposition. The mechanism of the selectivity of electroless deposition was investigated by X-ray photoelectron spectroscopy measurements. Tetravalent Sn and metallic Pd are observed on the inner electrode of the sample. On the other hand, metallic Sn and tetravalent Pd are mainly observed in certain areas except the inner electrode areas. These results indicate that the sensitization is performed well in the inner electrode region because Pd must be in a metallic state to validate its catalytic activity.

  6. Nickel-niobium alloy formation process of electroless nickel composite plating film using niobium nano-power

    International Nuclear Information System (INIS)

    Composite plating improves functionalities of wear resistance, corrosion resistance, lubricity, etc. through co-deposition with suitable particles. For this study, reactive metallic particles were introduced intentionally as a dispersant. Heat treatment was used to form an alloy with a plated matrix. Composite plating films were formed using electroless Ni-P plating with Nb powder of two types as dispersants: nanopowder (ca. 300 nm diameter) and micropowder (ca. 50 μm diameter). The composite plating film was alloyed using heat treatment at 800degC for 1 hour under vacuum conditions. X-ray diffraction (XRD) analysis confirmed that the proportion of alloy to reactive composite film with nanopowder was much larger than that with micropowder. Results of X-ray photoelectron spectroscopy (XPS) analyses suggest that a selective Nb oxide was formed on the composite film surface when using Nb nanopowder. On the other hand, almost no Nb micropowder was changed to alloy or oxide in the composite films. Using nanopowder, much of the composite plating film formed reactive composite plating film alloy during heat treatment. (author)

  7. Optimization and kinetics of electroless Ni-P-B plating of quartz optical fiber

    Science.gov (United States)

    Jiang, Boquan; Xiao, Lin; Hu, Shufen; Peng, Jian; Zhang, Hua; Wang, Minwei

    2009-08-01

    The preparation of Ni-P-B coatings on surface of quartz optical fibers was carried out using electroless plating method. The effects of the concentrations of nickel chloride, sodium hypophosphite, potassium borohydride, ethylenediamine, cadmium sulfate and temperature on the quality of Ni-P-B coatings were investigated by orthogonal experiment and their optimal values were determined to be: 0.1 mol L -1, 0.094 mol L -1, 0.185 mol L -1, 0.36 mol L -1, 5.68 × 10 -4 mol L -1 and 90 °C, respectively. The effect of coarsening time of the naked fiber on the quality of Ni-P-B coatings was also researched and the optimal coarsening time was determined to be 15 min. Stereomicroscope, Scanning Electron Microscope and X-ray diffractometer were used to characterize the apparentness, morphology and structure of the prepared Ni-P-B coatings. Inductively Coupled Plasma-Atomic Emission Spectroscopy, Thermal Shock Method and Gravimetric Analysis Method were employed to analyze the composition, force of adhesion and solderability of the coatings, respectively. The results showed that a Ni-P-B coating with low surface roughness, good strength of adhesion, low resistivity and good solderability was successfully prepared. The kinetic models (Ni-P-B deposition rate equations) of the process were established as v=7.95×10-6cA0.830cB0.428cC-0.288cD-0.645cE0..02exp{26788(T-298)298RT; v=1.03×10-7c}/{A0.830cB0.428cC-0.288cD-0.645cE-0.614exp 26788(T-298)298RT. The theoretical values calculated by the models were proved to be basically consistent with the practical measurements through experimental verification.

  8. Enhanced antioxidation and electromagnetic properties of Co-coated flaky carbonyl iron particles prepared by electroless plating

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Yingying, E-mail: zyzlchappy1989@163.com [State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an, Shaanxi 710072 (China); Zhou, Wancheng [State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an, Shaanxi 710072 (China); Li, Rong [State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an, Shaanxi 710072 (China); No. 603 Faculty, Xi’an Institute of High Technology, Xi’an 710025 (China); Mu, Yang; Qing, Yuchang [State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an, Shaanxi 710072 (China)

    2015-07-15

    Highlights: • Co-coated carbonyl iron particles were prepared by electroless plating method. • The obvious weight gain of carbonyl iron was deferred to 400 °C after Co-coated. • The permeability of the Co-coated particle composite kept almost invariable. • Co-coated carbonyl iron composite reserves a better absorption after heat treatment. - Abstract: Co was successfully coated on the surface of flaky carbonyl iron particles using an electroless plating method. The morphologies, composition, as well as magnetic, antioxidation and electromagnetic properties of the samples were characterized by scanning electron microscope (SEM), energy dispersive spectrometer (EDS), vibrating sample magnetometer (VSM), thermogravimetric (TG) and microwave network analyzer. TG curve shows that the obvious weight gain of carbonyl iron was deferred from 300 to 400 °C after Co-coated. In contrast to raw carbonyl iron, the Co-coated carbonyl iron shows better stability on electromagnetic properties after 300 °C heat treatment for 10 h, demonstrating that the Co coating can act as the protection of carbonyl iron.

  9. Development and Characterization of an Electroless Plated Silver/Cysteine Sensor Platform for the Electrochemical Determination of Aflatoxin B1

    Directory of Open Access Journals (Sweden)

    Alex Paul Wacoo

    2016-01-01

    Full Text Available An electroless plated silver/cysteine sensor platform [Glass|silver|cysteine|aflatoxin B1|horseradish peroxidase] for the Electrochemical detection of aflatoxin B1 was developed and characterized. This involved four major steps: (1 an electroless deposition of silver (plating onto a glass slide, (2 immobilization of cysteine; (3 conjugation of aflatoxin B1 to cysteine groups; and (4 blocking of free cysteine groups with horseradish peroxidase (HRP. The binding of cysteine to the silver was demonstrated by the disappearance of thiol (S-H groups at 2500 cm−1 using Fourier transmittance infrared spectra (FT-IR, while the subsequent steps in the assembly of sensor platform were monitored using both FT-IR and cyclic voltammetry, respectively. The sensor platform exhibited a broadened nonsymmetrical redox couple as indicated by cyclic voltammetry. The platform was further characterized for sensitivity and limit of detection. The indirect competitive immunoassay format, whereby free and immobilized aflatoxin B1 on the sensor competed for the binding site of free anti-aflatoxin B1 antibody, was used at various concentrations of aflatoxin B1. The sensor generated differential staircase voltammogram that was inversely proportional to the concentration of aflatoxin B1 and aflatoxin B1 in the range of 0.06–1.1 ng/mL with a detection limit of 0.08 ng/mL could be detected.

  10. Electroless Plating of Palladium on Stainless Steel Substrates in Hydrazine Solutions: A Study of the Relationships Between Bath Parameters, Deposition Mechanisms, and Deposit Morphologies

    Science.gov (United States)

    Davis, Stacy

    Development of a reliable and inexpensive method for producing hydrogen permeable membranes is of intense interest to ongoing fuel cell research. This study investigated electroless plating of palladium onto stainless steel substrates in hydrazine solution as a possible means of membrane production. Following initial research to establish the optimum infiltrant particle size, sensitization time, and activation time, electroless plating experiments were performed to determine the effects of varying hydrazine concentration, agitation, and residence time on the palladium deposit quality and morphology. SEM examination of the experimental products elucidated relationships between specific plating bath parameters or combinations of parameters, the governing deposition mechanisms, and the deposit morphologies. The results indicate that it is possible to produce application-specific deposit layer morphologies by modifying the plating bath parameters at critical stages of the plating cycle.

  11. Fabrication of Pd/Pd-Alloy Films by Surfactant Induced Electroless Plating for Hydrogen Separation from Advanced Coal Gasification Processes

    Energy Technology Data Exchange (ETDEWEB)

    Ilias, Shamsuddin; Kumar, Dhananjay

    2012-07-31

    Dense Pd, Pd-Cu and Pd-Ag composite membranes on microporous stainless steel substrate (MPSS) were fabricated by a novel electroless plating (EP) process. In the conventional Pd-EP process, the oxidation-reduction reactions between Pd-complex and hydrazine result in an evolution of NH{sub 3} and N{sub 2} gas bubbles. When adhered to the substrate surface and in the pores, these gas bubbles hinder uniform Pd-film deposition which results in dendrite growth leading to poor film formation. This problem was addressed by introducing cationic surfactant in the electroless plating process known as surfactant induced electroless plating (SIEP). The unique features of this innovation provide control of Pd-deposition rate, and Pd-grain size distribution. The surfactant molecules play an important role in the EP process by tailoring grain size and the process of agglomeration by removing tiny gas bubbles through adsorption at the gas-liquid interface. As a result surfactant can tailor a nanocrystalline Pd, Cu and Ag deposition in the film resulting in reduced membrane film thickness. Also, it produces a uniform, agglomerated film structure. The Pd-Cu and Pd-Ag membranes on MPSS support were fabricated by sequential deposition using SIEP method. The pre- and post-annealing characterizations of these membranes (Pd, Pd-Cu and Pd-Ag on MPSS substrate) were carried out by SEM, EDX, XRD, and AFM studies. The SEM images show significant improvement of the membrane surface morphology, in terms of metal grain structures and grain agglomeration compared to the membranes fabricated by conventional EP process. The SEM images and helium gas-tightness studies indicate that dense and thinner films of Pd, Pd-Cu and Pd-Ag membranes can be produced with shorter deposition time using surfactant. H{sub 2} Flux through the membranes fabricated by SIEP shows large improvement compared to those by CEP with comparable permselectivity. Pd-MPSS composite membrane was subjected to test for long term

  12. Effect of 2,2‧-dipyridyl on the plating rate, microstructure and performance of copper-coated tungsten composite powders prepared using electroless plating

    Science.gov (United States)

    Chen, Wenshu; Luo, Guoqiang; Li, Meijuan; Shen, Qiang; Wang, Chuanbin; Zhang, Lianmeng

    2014-05-01

    Highly pure copper-coated tungsten powders were successfully prepared in fixed quantities using electroless plating, via the addition of an appropriate amount of 2,2‧-dipyridyl to the plating bath. The effect of 2,2‧-dipyridyl on the plating Cu rate, microstructure and performance of the coated Cu layer was studied systematically. Changing the concentration of 2,2‧-dipyridyl had significant effects on the plating Cu rate, surface morphology, average grain size, purity and quantity of coated Cu. With a 2,2‧-dipyridyl concentration of approximately 20-40 mg/L, the coated Cu was highly pure, with very little oxygen content (less than 0.1 wt.%). The complexation of the 2,2‧-dipyridyl with cuprous ions and the absorption of the 2,2‧-dipyridyl on the coated Cu surface can explain these findings. With increase in the concentration of 2,2‧-dipyridyl in the plating bath, the plating Cu rate, microstructure and performance of the coated Cu layer changed steadily, indicating that the complexation and absorption of 2,2‧-dipyridyl gradually approached a saturation level. High thermal performance W-Cu composite can be fabricated by using these composite powders.

  13. State of the art on hydrogen passive auto-catalytic recombiner (european union Parsoar project)

    Energy Technology Data Exchange (ETDEWEB)

    Arnould, F.; Bachellerie, E. [Technicatome, 13 - Aix en Provence (France); Auglaire, M. [Tractebel Energy Engineering, Brussels (Belgium); Boeck, B. de [Association Vincotte Nuclear, Brussels (Belgium); Braillard, O. [CEA Cadarache, 13 - Saint Paul lez Durance (France); Eckardt, B. [Siemens AG, Offenbach am Main (Germany); Ferroni, F. [Electrowatt Engineering Limited, Zurich (Switzerland); Moffett, R. [Atomic Energy Canada Limited, Pinawa (Canada); Van Goethem, G. [European Commission, Brussels (Belgium)

    2001-07-01

    This paper presents an overview of the European Union PARSOAR project, which consists in carrying out a state of the art on hydrogen passive auto-catalytic recombiner (PAR) and a handbook guide for implementing these devices in nuclear power plants. This work is performed in the area ''Operational Safety of Existing Installations'' of the key action ''Nuclear Fission'' of the fifth Euratom Framework Programme (1998-2002). (author)

  14. The influence of platinum washing-out time on its recovery from used auto catalytic converters

    Directory of Open Access Journals (Sweden)

    A. Fornalczyk

    2014-07-01

    Full Text Available The used catalytic converters contain small amounts of precious metals. Recovery of these metals is essential for environmental and economic reasons. This work presents a method of Platinum Group Metals (PGM recovery from auto catalytic converters in which they are washed out by a liquid metal. The magneto-hydro-dynamic pump was used to force circulation of liquid metal under the influence of electromagnetic fields The influence of process time on platinum recovery was also carried out.

  15. State of the art on hydrogen passive auto-catalytic recombiner (european union Parsoar project)

    International Nuclear Information System (INIS)

    This paper presents an overview of the European Union PARSOAR project, which consists in carrying out a state of the art on hydrogen passive auto-catalytic recombiner (PAR) and a handbook guide for implementing these devices in nuclear power plants. This work is performed in the area ''Operational Safety of Existing Installations'' of the key action ''Nuclear Fission'' of the fifth Euratom Framework Programme (1998-2002). (author)

  16. Corrosion behaviors of electroless plating Ni-P coatings deposited on magnesium alloys in artificial sweat solution

    International Nuclear Information System (INIS)

    Magnesium alloys are the optimum shell materials for electronic products. These electronic products inevitably contact with the hands of users, and then are corroded by the sweat solution mainly consisting of 0.1% urea, 0.5% NaCl and 0.5% lactic acid. Electroless plating Ni-P coatings can provide protection to the magnesium alloys shell. The corrosion behaviors of Ni-P coatings deposited on AZ91D magnesium alloys in artificial sweat solution were investigated by electrochemical tests and SEM observations. The results indicated that urea acted as corrosion inhibitor. The inhibiting effect of urea was reduced in NaCl solution or lactic acid solution. NaCl and lactic acid were the main corrosive mediums, and their synergistic effect can significantly accelerate the corrosion of Ni-P coatings

  17. Ultraviolet light and ozone surface modification of poly-alpha α-methylstyrene using electroless nickel plating

    International Nuclear Information System (INIS)

    The deposition capability of nickel on the surface of poly-α-methylstyrene microspheres was improved by combined treatment of ozone aeration and UV irradiation in aqueous ammonia. Surface properties of the treated film were investigated by X-ray photoelectron spectroscopy(XPS) and Fourier transform infrared(FT-TR) measurements. The samples were characterized by SEM. The results indicate that after ultraviolet joint ozone treatment, the surfaces of microspheres were oxidized, and the amine and amide groups are introduced on their surface. The images of SEM show the adhesion between microspheres and nickel-phosphorus films was improved after surface modification. This was attributed to amide which could chemisorb palladium ions to catalyze electroless nickel plating on the pretreated surface of microspheres. (authors)

  18. Fabrication of dielectric and metallo-dielectric 3D nanostructures by direct laser writing and electroless plating

    Science.gov (United States)

    Radke, André; Wolff, Frank; Giessen, Harald; Klotzbücher, Thomas

    2010-02-01

    Direct laser writing via two-photon absorption allows the fabrication of three-dimensional dielectric structures with submicron resolution by tightly focusing ultrashort laser pulses into a photo-sensitive material with a high-resolution microscope objective and scanning the laser focus relative to the material. Woodpile photonic crystals fabricated with this method show a characteristic dip in transmission at near-infrared wavelengths. The spectral position of this transmission dip scales with the grating period of the fabricated crystals. Metallo-dielectric structures can be obtained by first fabricating dielectric templates with direct laser writing and subsequently coating the templates with a thin conformal metal film by electroless plating. Contiguous and conducting silver films can be deposited even on convoluted 3D geometries.

  19. 化学镀可焊性锡基合金的研究进展%Progress of research on electroless plating of solderable tin alloy

    Institute of Scientific and Technical Information of China (English)

    赵国鹏; 樊江莉; 温青

    2001-01-01

    本文综述了近10年来化学镀可焊性锡基合金的研究现状及动态。列举了4种不同镀液体系的典型配方及工艺,并对化学镀锡合金的未来发展提出了建议。%Current status and prospect of solderable electroless tin alloy plating were summarized with 18 references published in the recent decade. Four traditional plating solutions based on chloride, fluoboric, alkyl sulfonate and ethane sulfonate were exemplified. Suggestions were presented about the develoment of electroless plating of solderable tin alloy.

  20. Application of Ni-P Alloy Electroless Plating in Rapier Head

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhao-jun; LIU Ying

    2004-01-01

    A way which uses electrcless plating of Ni-P alloy to treat the Al-alloy-rapier head, instead of the import one, is introduced. After analyzing the effect of pretreatment, plating solution formula, plating technique and post heat treatment, a simple and practicable plating and post-heat-treat technique is found out. The performance of the determined plating solution formula is stable. A plating coat thickness more than 40 μm can be obtained. The combination of the plating coat with base is good. The hardness of the coat is above 1100 HV. Its multiple performance is equal to the import one's.

  1. Effects of Hard Surface Grinding and Activation on Electroless-Nickel Plating on Cast Aluminium Alloy Substrates

    Directory of Open Access Journals (Sweden)

    Olawale Olarewaju Ajibola

    2014-01-01

    Full Text Available This work examined effects of hard surface polishing grits and activation on electroless-nickel (EN plating on cast aluminium alloy substrates in sodium hypophosphite baths. As-received aluminium alloy sample sourced from automobile hydraulic brake master cylinder piston was melted in electric furnace and sand cast into rod. The cast samples were polished using different grits (60 μm–1200 μm before plating. The effects on adhesion, appearance, and quantity of EN deposits on substrates were studied. Observation shows that the quantity of EN deposit is partly dependent on the alloy type and roughness of the surface of the substrates, whereas the adhesion and brightness are not solely controlled by the degree of surface polishing. The best yield in terms of adhesion and appearance was obtained from the activation in zincate and palladium chloride solutions. Higher plating rates (g/mm2/min of 3.01E-05, 2.41E-05, and 2.90E-05 were obtained from chromate, zincate, and chloride than 8.49E-06, 8.86E-06, and 1.69E-05 as obtained from HCl etched, NaOH, and H2O activated surfaces, respectively.

  2. Estimation of fatigue evolution of aluminum alloy plated with electroless NI–CO–P by using electromagnetic impedance method

    Energy Technology Data Exchange (ETDEWEB)

    Kinoshita, Katsuyuki

    2015-02-01

    We have developed a method for detecting fatigue in aluminum alloys that is based on a applying a ferromagnetic electroless Ni–Co–P plating and then using an electromagnetic impedance (EMI) method to determine its permeability properties by measuring the high-frequency AC impedance of a coil sensor in the presence of a static magnetic field. The results obtained confirmed that this method can estimate the fatigue evolution of a specimen until the point at which the cumulative strain becomes saturated by using measurements obtained by the EMI method under tensile deformation and FEM analysis results. - Highlights: • Plating aluminum alloy with Ni–Co–P film increases its fatigue strength by 13−16%. • The tensile direction is the stress induced “hard axis” of the Ni–Co–P plating. • In-plane permeability determines the coil impedance for out-of-plane excitation. • This method can measure fatigue up to saturation of the substrate's residual strain.

  3. Estimation of fatigue evolution of aluminum alloy plated with electroless NI–CO–P by using electromagnetic impedance method

    International Nuclear Information System (INIS)

    We have developed a method for detecting fatigue in aluminum alloys that is based on a applying a ferromagnetic electroless Ni–Co–P plating and then using an electromagnetic impedance (EMI) method to determine its permeability properties by measuring the high-frequency AC impedance of a coil sensor in the presence of a static magnetic field. The results obtained confirmed that this method can estimate the fatigue evolution of a specimen until the point at which the cumulative strain becomes saturated by using measurements obtained by the EMI method under tensile deformation and FEM analysis results. - Highlights: • Plating aluminum alloy with Ni–Co–P film increases its fatigue strength by 13−16%. • The tensile direction is the stress induced “hard axis” of the Ni–Co–P plating. • In-plane permeability determines the coil impedance for out-of-plane excitation. • This method can measure fatigue up to saturation of the substrate's residual strain

  4. Electroless plating of Cu-Ni-P alloy on PET fabrics and effect of plating parameters on the properties of conductive fabrics

    Energy Technology Data Exchange (ETDEWEB)

    Gan Xueping; Wu Yating; Liu Lei; Shen Bin [State Key Laboratory of Metal Matrix Composites, Shanghai Jiaotong University, Shanghai 200030 (China); Hu Wenbin [State Key Laboratory of Metal Matrix Composites, Shanghai Jiaotong University, Shanghai 200030 (China)], E-mail: jh13zhang@hotmail.com

    2008-05-08

    Electroless plating of Cu-Ni-P alloy on polyethylene terephthalate (PET) fabrics and effect of plating parameters on the properties of alloy-coated fabrics were investigated. The deposition rate increased with the increase of temperature, pH and nickel ion concentration. The addition of K{sub 4}Fe(CN){sub 6} to the solution could reduce the deposition rate and make the deposits become more compact. The color of the deposits also had a corresponding improvement, changing from dark-brown to copper-bright with the addition of K{sub 4}Fe(CN){sub 6} to the plating solution. The deposits have an intensified copper (1 1 1) plane orientation with the addition of K{sub 4}Fe(CN){sub 6} to the plating bath. The surface electrical resistance of alloy-coated fabrics increased with increase of nickel ions concentration in the solution. The addition of K{sub 4}Fe(CN){sub 6} to the solution reduced significantly the surface resistance of alloy-coated fabrics. The conductive fabrics with high shielding effectiveness could be prepared at the optimum condition with 0.0038 M nickel ions and 2 ppm K{sub 4}Fe(CN){sub 6}. As the deposit weight on the fabric was 40 g/m{sup 2}, the shielding effectiveness of alloy-coated fabrics was more than 85 dB at frequency ranging from 100 MHz to 20 GHz.

  5. Collection of Ni-bearing material from electroless plating waste by magnetic separation with HTS bulk magnet

    Energy Technology Data Exchange (ETDEWEB)

    Oka, T., E-mail: okat@eng.niigata-u.ac.jp [Niigata University, 8050 Ikarashi-Ninocho, Nishi-ku, Niigata 950-2181 (Japan); Fukazawa, H.; Fukui, S.; Ogawa, J.; Sato, T.; Ooizumi, M. [Niigata University, 8050 Ikarashi-Ninocho, Nishi-ku, Niigata 950-2181 (Japan); Tsujimura, M. [Aichi Giken Co., 50-1 Takeshita, Hitotugi-cho, Kariya, Aichi 448-0003 (Japan); Yokoyama, K. [Ashikaga Institute of Technology, 268-1 Ohmae-cho, Ashikaga, Tochigi 326-8558 (Japan)

    2014-01-15

    Highlights: ► The magnetic separation for Ni compounds was conducted by HTS bulk magnet. ► The coarse Ni-sulfate crystals were formed from the Ni-phosphite precipitates. ► Ni-sulfate crystals was separated from the mixture of Ni-sulfate and Ni-phosphite compounds. -- Abstract: The magnetic separation experiment to collect the Ni compounds from the waste liquid of electroless plating processes was conducted in the open-gradient magnetic separation process with the high temperature superconducting bulk magnet system. The magnetic pole containing Gd-based bulk superconductors was activated to 3.45 T at 35 K in the static magnetic field of 5 T with use of a superconducting solenoid magnet. The coarse Ni-sulfate crystals were formed by adding the concentrated sulfuric acid to the Ni-phosphite precipitates which yielded from the plating waste liquid by controlling the temperature and the pH value. The open-gradient magnetic separation technique was employed to separate the Ni-sulfate crystals from the mixture of the Ni-sulfate and Ni-phosphite compounds by the difference between their magnetic properties. And we succeeded in collecting Ni-sulfate crystals preferentially to the Ni-phosphite by attracting them to the magnetic pole soon after the Ni-sulfate crystals began to grow.

  6. PREPARATION OF MICROWAVE ABSORBING NICKEL-BASED ACTIVATED CARBON BY ELECTROLESS PLATING WITH PALLADIUM-FREE ACTIVATION

    Directory of Open Access Journals (Sweden)

    Boyang Jia

    2010-08-01

    Full Text Available Nickel-based activated carbon was prepared from coconut shell activated carbon by electroless plating with palladium-free activation. The materials were characterized by scanning electron microscopy (SEM, X-ray energy dispersion spectroscopy (EDS, vibrating sample magnetometry (VSM, and vector network analyzer, respectively. The results show that the surface of the activated carbon was covered by a Ni-P coating, which was uniform, compact, and continuous and had an obvious metallic sheen. The content of P and Ni was 2.73% and 97.27% in the coating. Compared with the untreated activated carbon, the real permeability μ′ and imaginary permeability μ″ of Ni-based activated carbon became greater, whereas the real permittivity ε′ and imaginary permittivity ε″ became smaller. Also, the plated activated carbon was magnetic, making it suitable for some special applications. In general, the method reported here might be a feasible procedure to coat activated carbon with other magnetic metals, which may find application in various areas.

  7. Al/Pb lightweight grids prepared by molten salt electroless plating for application in lead-acid batteries

    Science.gov (United States)

    Hong, Bo; Jiang, Liangxing; Hao, Ketao; Liu, Fangyang; Yu, Xiaoying; Xue, Haitao; Li, Jie; Liu, Yexiang

    2014-06-01

    In this paper, a lightweight Pb plated Al (Al/Pb) grid was prepared by molten salt electroless plating. The SEM and bonding strength test show that the lead coating is deposited with a smooth surface and firm combination. CV test shows that the electrochemical properties of Al/Pb electrodes are stable. 2.0 V single-cell flooded lead-acid batteries with Al/Pb grids as negative collectors are assembled and the performances including 20 h capacity, rate capacity, cycle life, internal resistance are investigated. The results show that the cycle life of Al/Pb-grid cells is about 475 cycles and can meet the requirement of lead-acid batteries. Al/Pb grids are conducive to the refinement of PbSO4 grain, and thereby reduce the internal resistance of battery and advance the utilization of active mass. Moreover, weight of Al/Pb grid is only 55.4% of the conventional-grid. In this way, mass specific capacity of Al/Pb-grid negatives is 17.8% higher and the utilization of active mass is 6.5% higher than conventional-grid negatives.

  8. Effects of TiN nanoparticles on the microstructure and properties of W–30Cu composites prepared via electroless plating and powder metallurgy

    International Nuclear Information System (INIS)

    Highlights: • TiN-doped W–Cu composite was successfully prepared by electroless plating and powder metallurgy. • TiN-doped W–Cu significantly affected the microstructure and properties of the composites. • W–Cu composite with 0.25 wt.% TiN possesses the best comprehensive performance. - Abstract: W–30Cu/(0, 0.25, 0.5, 1, and 2) wt.% TiN composites were prepared via electroless plating with simplified pretreatment and powder metallurgy. The phase and morphology of W–Cu/TiN composite powders and sintered W–Cu/TiN samples were characterized via X-ray diffraction and field emission scanning electron microscopy. Transmission electron microscopy was performed to characterize the microstructure of the sintered W–Cu/TiN samples. The relative density, hardness, electrical conductivity, and compressive strength of the sintered samples were examined. Results showed that W–30Cu composite powders with a uniform structure can be obtained using W powder pretreated with nitric acid, ammonium fluoride, and hydrofluoric acid followed by electroless Cu plating. The addition of TiN nanoparticles significantly affected the microstructure and properties of the W–30Cu composites. A good combination of the compressive strength and hardness of the W–30Cu composite material can be obtained by incorporating the TiN additive at 0.25 wt.%. However, the relative density and electrical conductivity slightly decreased

  9. Fabrication and Characteristics of High Capacitance Al Thin Films Capacitor Using a Polymer Inhibitor Bath in Electroless Plating Process.

    Science.gov (United States)

    Cho, Young-Lae; Lee, Jung-Woo; Lee, Chang-Hyoung; Choi, Hyung-Seon; Kim, Sung-Su; Song, Young Il; Park, Chan; Suh, Su-Jeong

    2015-10-01

    An aluminum (Al) thin film capacitor was fabricated for a high capacitance capacitor using electrochemical etching, barrier-type anodizing, and electroless Ni-P plating. In this study, we focused on the bottom-up filling of Ni-P electrodes on Al2O3/Al with etched tunnels. The Al tunnel pits were irregularly distributed on the Al foil, diameters were in the range of about 0.5~1 μm, the depth of the tunnel pits was approximately 35~40 μm, and the complex structure was made full filled hard metal. To control the plating rate, the experiment was performed by adding polyethyleneimine (PEI, C2H5N), a high molecular substance. PEI forms a cross-link at the etching tunnel inlet, playing the role of delaying the inlet plating. When the PEI solution bath was used after activation, the Ni-P layer was deposited selectively on the bottoms of the tunnels. The characteristics were analyzed by adding the PEI addition quantity rate of 100~600 mg/L into the DI water. The capacitance of the Ni-P/Al2O3 (650~700 nm)/Al film was measured at 1 kHz using an impedance/gain phase analyzer. For the plane film without etch tunnels the capacitance was 12.5 nF/cm2 and for the etch film with Ni-P bottom-up filling the capacitance was 92 nF/cm2. These results illustrate a remarkable maximization of capacitance for thin film metal capacitors. PMID:26726471

  10. Surface-enhanced Raman scattering substrates fabricated using electroless plating on polymer-templated nanostructures.

    Science.gov (United States)

    Bantz, Kyle C; Haynes, Christy L

    2008-06-01

    Surface-enhanced Raman scattering (SERS) has great potential as an analytical technique based on the unique molecular signatures presented even by structurally similar analyte species and the minimal interference of scattering from water when sampling in aqueous environments. Unfortunately, analytical SERS applications have been restricted on the basis of limitations in substrate design. Herein, we present a simple SERS substrate that exploits electroless deposition onto a nanoparticle-seeded polymer scaffold that can be fabricated quickly and without specialized equipment. The polymer-templated nanostructures have stable enhancement factors that are comparable to the traditional silver film over nanospheres (AgFON) substrate, broad localized surface plasmon resonance spectra that allow various Raman excitation wavelengths to be utilized, and tolerance for both aqueous and organic environments, even after 5 day exposure. These polymer-templated nanostructures have an advantage over the AgFON substrate based on the ease of fabrication; specifically, the ability to generate fresh SERS substrates outside the laboratory environment will facilitate the application of SERS to new analytical spectroscopy applications. PMID:18461977

  11. A novel auto-catalytic deposition methodology to produce calcium-phosphate coatings on polymeric biomaterials

    Energy Technology Data Exchange (ETDEWEB)

    Leonor, I.B.; Reis, R.L. [Universidade do Minho, Braga (Portugal). Dept. of Polymer Engineering

    2001-07-01

    The aim of this research is to develop a new methodology to obtain bioactive coatings on bioinert and biodegradable polymers that are not intrinsically bioactive. In this study three types of materials were used as substrates: (i) high molecular weight polyethylene (HMWPE) and two different types of biodegradable starch based blends (ii) starch/ethylene vinyl alcohol blends, SEVA-C and (iii) starch/cellulose acetate blends, SCA, both from Novamont, Italy. These materials were obtained by injection moulding. Two types of baths were studied to produce the novel proposed auto-catalytic Ca-P, coatings: (i) alkaline and (ii) acid bath. The obtained results indicated that it was possible to coat the materials surfaces with Ca-P layer with only 60 min of immersion in both types of auto-catalytic solutions. These new methodologies allow for the production of an adherent bioactive film on the polymeric surfaces. Furthermore, it was possible observe the clear bioactive nature of the Ca-P coatings after different immersion periods in a simulated body fluid (SBF). (orig.)

  12. Preparation and Magnetic Properties of Anisotropic (Sm,PrCo5/Fe Nanocomposites Particles via Electroless Plating

    Directory of Open Access Journals (Sweden)

    Shi Wang

    2014-01-01

    Full Text Available Anisotropic (Sm,PrCo5/Fe nanocomposites particles were prepared by electroless plating iron on the surface of (Sm,PrCo5 nanoflakes after being prepared by ball milling for 4 h. A uniform and continuous coating layer was obtained due to the addition of complexing agent and the particle size of the reduced Fe particles was in the range of 10~20 nm. When the nominal addition of Fe was 15 wt%, the nanocomposites show enhanced remnant and saturation magnetization: Mr=53.35 emu/g, Ms=73.08 emu/g compared to the noncoated nanoflakes with Mr=48.52 emu/g, Ms=60.15 emu/g, while the coercivity drops from 10.33 kOe to 8.89 kOe. The effect of Fe content on the magnetic properties of the magnets is also discussed.

  13. Structure and Mechanical Properties of Ni-P-Nano Al2O3 Composite Coatings Synthesized by Electroless Plating

    Institute of Scientific and Technical Information of China (English)

    ZHOU Guang-hong; DING Hong-yan; ZHOU Fei; ZHANG Yue

    2008-01-01

    Ni-P-nano Al2O3 composite coatings were deposited by electroless plating, and their microstructures were observed by SEM (scanning electron microscope). The microhardness and the wear resistance of the Ni-P-nano Al2O3 composite coatings were measured using microhardness tester and block-on-ring tribometer, respectively, and the comparison with those of Ni-P coatings or Ni-P-micro Al2O3 coating was given. The influences of aging temperature on their hardness and wear resistance were analyzed. The results showed that the nano Al2O3 particles were distributed uniformly in the Ni-P-Al2O3 coatings. Among three kinds of Ni-P based coatings, the hardness and wear resistance of Ni-P-nano Al2O3 coatings were largest, and the maximum values could be obtained at 400 ℃. This indicated that the precipitation of nano Al2O3 particles would improve the hardness and wear resistance of the Ni-P coatings.

  14. The Microstructure and Thermal Conductivity of Pressureless Infiltrated SiCp/Al Composites Containing Electroless Nickel Platings

    Directory of Open Access Journals (Sweden)

    Aihua Zou

    2015-01-01

    Full Text Available A nickel (Ni coating was deposited on the surface of silicon carbide particles (SiCp through electroless plating and we characterized the morphology and phase structure of the coating and the pressureless infiltrated SiCp/Al composites. The effect of Ni coatings on the thermal conductivity of the composites was examined and analyzed with three-dimensional video microscope, scanning electron microscope (SEM, energy-dispersive X-ray spectroscopy (EDS, X-ray diffraction microscope (XRD, and finite-element. The results show that a continuous and uniform coating with a certain thickness (around 3.5 μm can be formed on the surface of SiCp. With the addition of the Ni layer, there are some intermetallics Ni3Al but no interfacial carbide Al4C3, which improves the wettability and the thermal conductivity of the composites. The experiments and simulations both show that Ni coatings do not substantially decrease the overall thermal conductivity of the composite, although the thermal conductivity of Ni itself is lower than Al and SiC by a factor of 1.

  15. Absorption kinetics deuterium by Zr3Al2 covered with electroless Pd plating. Durability against impurity gases

    International Nuclear Information System (INIS)

    Electroless Pd plating on Zr3Al2 granules was prepared as a protective layer on the getter alloy surface. The absorption of deuterium obeyed the first order kinetics with respect to the deuterium pressure for both Zr3Al2 and Pd/Zr3Al2. The rate determining step for absorption was the dissociation reaction of gaseous and/or adsorbed deuterium molecules on the surface. The activation energy was evaluated to be 7.4 and 8.9 kJ/mol (D2) for Zr3Al2 and Pd/Zr3Al2, respectively. In addition, the durability against impurity gases for deuterium absorption was also demonstrated using CO2 and N2 as impurity gases. Exposure to these impurity gases caused a reduction of the absorption rate of deuterium. The extent of the reduction for Pd/Zr3Al2 was smaller than that for bare Zr3Al2. The effectiveness of the Pd-overlayer against impurity gases was in the order of N2 > CO2. The results could be explained in terms of different absorption properties of deuterium between Pd and Zr. (author)

  16. Electroless plating of silver on cenosphere particles and the investigation of its corrosion behavior in composite silicon rubber

    Science.gov (United States)

    Hu, Yong-jun; Zhang, Hai-yan; Cheng, Xiao-ling; Li, Feng; Chen, Tian-li

    2011-01-01

    In this paper, silver coating on the surface of cenosphere particles was prepared by electroless plating method. The adhesion, oxidation resistance and corrosion resistance properties of silver coating mixed in silicone rubber were investigated. The corrosion characteristic of silver coating was evaluated by anodic polarization curves of the silicone rubber composite in sulfuric acid solution. The results showed that the silver coating on the surface of cenosphere particles was smooth and uniform. The silver film was not oxidized and peeling off during preparation of composite silicone rubber. The adhesion between the cenosphere particle and silver film was good enough. The anodic polarization curves of the silicone rubber composite showed typical activation and passivation transformation. The values of corrosion potential, the initiating passive potential and maintaining passivity potential of composites filled with different contents of Ag-coated cenosphere particles were the same and related to the nature of silver coating. The passive current density of composite increased with increase of the amount of Ag-coated cenosphere particles and was inversely proportional to the resistance of silicone rubber composite. The better the conductivity of silicone rubber composite is, the higher corrosion rate will be.

  17. NH3 Plasma Surface Treatments of Engineering Fluoropolymers: A Way to Enhance Adhesion of Ni or Cu Thin Films Deposited by Electroless Plating

    Institute of Scientific and Technical Information of China (English)

    MauriceRomand; MarleneCharbonnier; YvesGoepfert

    2004-01-01

    This paper describes the electroless Ni or Cu plating of some fluoropolymer substrates through a tin-free activation process. Materials subjected to surface metallization are commercial Teflon FEE Nation, ACLAR and LaRCTM-CP1 thin films which have recently gained a large scientific and technological interest due to their excellent thermal, chemical, mechanical and dielectric properties. The original approach implemented in the present work involves: (i) the grafting of nitrogen-containing functionalities on the polymer surfaces through plasma treatments in ammonia, (ii) the direct catalysis of the so-modified surfaces via their immersion insurface sensitization in an acidic SnCl2 solution), and finally (iii)a simple acidic PdCl2 solution (i.e. without using a prior the electroless metallization itself. However, prior to the immersion in the industrial plating baths, the chemical reduction of the Pd+1 species (species covalently tethered on the nitrogen-containing groups) to metallic palladium (Pd0) is shown to be a key factor in catalyzing the electroless deposition initiation. This is made by immersion in an hypophosphite (H2PO2-) solution. Wettability measurements and X-ray photoelectron spectroscopy (XPS) experiments are used to characterize every surface modification step of the developed process. A cross-hatch tape test was used to asses the adhesion strength of the electroless films that is shown qualitatively good. In addition, a fragmentation test was developed in combination with electrical measurements. Its use allows to distinguish different adhesion levels at the metal/polymer interface and to evidence the influence of some processing parameters.

  18. NH3 Plasma Surface Treatments of Engineering Fluoropolymers:A Way toEnhance Adhesion of Ni or Cu Thin Films Deposited by Electroless Plating

    Institute of Scientific and Technical Information of China (English)

    Maurice Romand; Marlène Charbonnier; Yves Goepfert

    2004-01-01

    This paper describes the electroless Ni or Cu plating of some fiuoropolymer substrates through a tin-free activation process. Materials subjected to surface metallization are commercial Teflon() FEP, Nafion(), ACLAR() and LaRCTM-CP1 thin films which have recently gained a large scientific and technological interest due to their excellent thermal, chemical, mechanical and dielectric properties. The original approach implemented in the present work involves: (i)the grafting of nitrogen-containing functionalities on the polymer surfaces through plasma treatments in ammonia, (ii) the direct catalysis of the so-modified surfaces via their immersion in a simple acidic PdCl2 solution (i.e. without using a prior surface sensitization in an acidic SnCl2 solution), and finally (iii) the electroless metallization itself. However, prior to the immersion in the industrial plating baths, the chemical reduction of the Pd+2 species (species covalently tethered on the nitrogen-containing groups) to metallic palladium (PdO) is shown to be a key factor in catalyzing the electroless deposition initiation. This is made by immersion in an hypophosphite (H2PO2-) solution. Wettability measurements and X-ray photoelectron spectroscopy (XPS) experiments are used to characterize every surface modification step of the developed process. A cross-hatch tape test was used to asses the adhesion strength of the electroless films that is shown qualitatively good. In addition, a fragmentation test was developed in combination with electrical measurements. Its use allows to distinguish different adhesion levels at the metal/polymer interface and to evidence the influence of some processing parameters.

  19. Electroless nickel plating with different pre-treatments on silicon carbide particles

    International Nuclear Information System (INIS)

    Complete text of publication follows. The quality of interface between the reinforcing phase and the metallic matrix plays a very important role during the production of Al/SiC composites by means of powder metallurgy. A transient layer, a plating shall be developed on the reinforcing particles in order to form a better mechanical contact between the ceramic particles and the metallic matrix. Owing to the inert surface of siliconcarbide, the metallic layer can be formed by a chemical reduction only in case if a surface activation is carried out. Different types of pretreating materials were tried out in order to do this procedure. A partial activation can be obtained after the pre-treatment by using Nahypophosphite and lactic acid and therefore the desired plating is not continuous. A compact layer of silica formed at the surface of the ceramic particles in the course of surface oxidation by which a compact plating can be developed in case of a stable chemical Nibath. The development of continuous plating is promoted by the formation of metallic palladium nuclei in the course of using the twostep activation by palladium-chloride. The developed pre-treating layers were studied by a home-built XPS equipment (some details of the equipment can be found in refs [2], [3], [4]) and XRD method and the final coating layers developed by the plating process was studied by SEM. Acknowledgements One of the authors J.T. is indebted for the support of the Hungarian Science Foundation OTKA: (No K67873).

  20. Deposition of Gold Nanoparticles on Polystyrene Spheres by Electroless Metal Plating Technique

    International Nuclear Information System (INIS)

    A previous method proposed for gold deposition on silica spheres (Kobayashi et al., 2005) was extended to uniform deposition of Au nanoparticles on submicron-sized polystyrene spheres. This method consisted of surface-modification and elecroless Au plating. The chemical agents examined for the surface-modification were sodium persulfate, 3- aminopropyltrimethoxysilane, polyelectrolytes and polyvinylpyrrolidone. The elecroless Au plating included three steps: (1) the adsorption of Sn2+ ions took place on surface of silica particles (2) Ag+ ions added were reduced and simultaneously adsorbed to the surface, while Sn2+ oxidized to Sn4+, and (3) Au+ ions added were reduced and deposited on the Ag surface. TEM observation revealed that Au nanoparticles with sizes of 8-25 nm were uniformly deposited on the polystyrene spheres that were modified with polyvinylpyrrolidone. The Au nanoparticle deposition was confirmed by UV-VIS absorption spectroscopy

  1. CFD simulation of hydrogen mixing and mitigation by means of passive auto-catalytic recombiners

    Energy Technology Data Exchange (ETDEWEB)

    Kelm, S.; Reinecke, E-A.; Jahn, W., E-mail: s.kelm@fz-juelich.de [Forschungszentrum Juelich GmbH, Juelich (Germany); Allelein, H-J. [RWTH Aachen Univ.. Aachen (Germany)

    2011-07-01

    Modeling of passive auto-catalytic recombiners (PARs) operation in containment geometries involves a large variety of scales; thus, a CFD calculation resolving all these scales would be much too expensive. Therefore, the mechanistic PAR model REKO-DIREKT, developed at Forschungszentrum Juelich, has been coupled with the commercial CFD code ANSYS CFX in order to simulate PAR operation as well as the induced flow and transport phenomena. Based on a short introduction of REKO-DIREKT, its interface to CFX and the explicit coupling scheme is discussed. The paper is finalized by a first demonstration of simulation capabilities on the basis of the ThAI PAR-4 experiment (Becker Technologies GmbH, Eschborn, Germany). (author)

  2. Analysis of continuous solvent extraction of nickel from spent electroless nickel plating baths by a mixer-settler

    International Nuclear Information System (INIS)

    It is urgent to develop an effective technique to treat the large amount of spent electroless nickel plating bath and recycle the high concentration nickel. In our previous study, high recycling efficiency of nickel from the model spent bath was obtained by continuous solvent extraction with 2-hydroxy-5-nonylacetophenone oxime (LIX84I) as the extractant and 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (PC88A) as the accelerator using a mixer-settler extractor. It was observed that the extraction efficiency was affected by the operation parameters such as the flow rates of the aqueous and organic phases and the total stage number. In the present study, the effects of the operation parameters on the extraction efficiency were quantitatively studied on the basis of the pseudo-first-order interfacial extraction rate equation together with the hydrodynamic properties in the mixer. The organic phase holdup, measured under varying conditions of the flow rates of both phases, was analyzed by the Takahashi-Takeuchi holdup model in order to estimate the specific interfacial area. The overall extraction rate coefficients defined by the product of the interfacial extraction rate constant and the specific interfacial area were evaluated using the experimental data and ranged from 3.5 x 10-3 to 6.7 x 10-3 s-1, which was close to the value of 3.4 x 10-3 s-1 obtained by batch extraction. Finally, an engineering simulation method was established for assessing the extraction efficiency of nickel during a multistage operation.

  3. Analysis of using magneto-hydro-dynamic pump for the platinum recovery from spent auto catalytic converters

    Directory of Open Access Journals (Sweden)

    A. Fornalczyk

    2012-12-01

    Full Text Available Purpose: Applying the catalytic converters allow to eliminate the compounds harmful to the environment. Typical catalytic converter is built from the metallic or ceramic carrier with porous structure covered with the PGM metals especially platinum, palladium and rhodium. The content of these metals is on average about 2 grams. Catalytic converters have limited life time, and then they are scrapped. The necessity of waste disposal and very high prices of PGM metals are the reason why recovery of PGM metals from used auto catalytic converters has become more and more profitable.Design/methodology/approach: This work presents method of PGM metals recovery from auto catalytic converters by means of solving them in the liquid metal. Liquid metal is put in motion using magneto-hydrodynamic pump, and then the PGM metals are eluted from channels of the used auto catalytic converters.Findings: All over the world the used auto catalytic converters are preceded by the use of pyrometallurgical, hydrometallurgical or mixed methods. Each method has some disadvantages. Pyrometallurgical methods need to use units which assure the necessary temperature. This is as expensive as energy consuming. Applying hydrometallurgical methods involve danger of creating many waste solutions which are harmful to the natural environment.Practical implications: The way PGM metals are recovered from used auto catalytic converters by their dissolution in the liquid rotating metal allows to increase concentration of PGM metals in the solution by means of applying the same metal collector to flush other catalytic collectors. Motion of the metal essentially shorten the time of PGM metals elution from catalytic converters; whereas the flow of liquid metal in closed cycle limits the unfavorable influence of the process on the environment.Originality/value: Method presented in this article is an innovative method and has never been applied. Additionally it is protected by a patent.

  4. Surface-enhanced Raman scattering of patterned copper nanostructure electrolessly plated on arrayed nanoporous silicon pillars

    Energy Technology Data Exchange (ETDEWEB)

    Jiang Weifen; Shan Wenwen; Ling Hong; Wang Yusheng [Department of Mathematics and Information Science, North China Institute of Water Conservancy and Hydroelectric Power, Zhengzhou 450011 (China); Cao Yanxia [College of Materials Engineering, Zhengzhou University, Zhengzhou 450052, People' s Republic of China (China); Li Xinjian, E-mail: gingerwfj@yahoo.com.c [Department of Physics and Laboratory of Material Physics, Zhengzhou University, Zhengzhou 450052 (China)

    2010-10-20

    A new synthesized composite structure, a patterned copper/silicon nanoporous pillar array (Cu/Si-NPA) made by depositing Cu on Si-NPA using an immersion plating method, can be used as a surface-enhanced Raman scattering (SERS) substrate. Its surface component and morphology were analyzed by x-ray diffraction and field-emission scanning electron microscopy, respectively. It was found that the surface was Cu with two kinds of crystal structures: a continuous film composed of Cu nanocrystallites covering the Si-NPA, and a quasi-regular, interconnected network composed of loop-chains of Cu crystallites, with the size in the range of several tens of nanometer to 300 nm, surrounding the porous Si pillars. The composite structure is strongly SERS active using rhodamine 6G as probe molecules, which is mainly due to the patterned hierarchical Cu structure.

  5. Electroless plating of Ni-Zn(Fe)-P alloy on carbon steel sheets

    Institute of Scientific and Technical Information of China (English)

    WANG Sen-lin; WU Hui-huang

    2004-01-01

    The autocatalytic deposition of Ni-Zn(Fe)-P alloys were carried out on carbon steel sheets from bath containing nickel sulfate, zinc sulfate, sodium hypophosphite, sodium citrate and boric acid. The effects of pH and mole ratio of NiSO4/ZnSO4 on the deposition rate and the composition of deposit were studied. It is found that the presence of zinc sulfate in the bath has an inhibitory effect on the alloy deposition. As a consequence, the mole fraction of zinc in the deposits never reaches high value, which is less than 18.0%. The structure and surface morphology of Ni-Zn(Fe)-P coatings were charactered by XRD and SEM. The alloys plated at all conditions consist of amorphous phase coexisting with a crystalline cubic Ni phase. The surface morphology of coating is dependent on the deposition parameters.

  6. Microstructure and magnetic properties of C/Co-P and Al2O3/Co-P composite particles prepared by electroless plating

    Science.gov (United States)

    Denisova, E. A.; Chekanova, L. A.; Iskhakov, R. S.; Bondarenko, G. N.

    2013-05-01

    The electroless plating is used to synthesize two types of composite powder, such as the activated carbon with pores filled by Co100-XPX particles and the Al2O3 microgranular coated by the shell which consists of Co100-XPX particles with 4 powders decreases from 300 nm to 120 nm with an increase in P- content from 4 to 18 at. %. It causes a reduction in coercivity from 300 to 80 Oe for Al2O3/Co(P) powders and from 680 to 150 Oe for C/Co(P) powders. The effects of two methods of immobilization of Co(P) particles on magnetic properties are studied.

  7. Supercritical CO2 assisted electroless plating on polypropylene substrate-effect of injection speed on adhesive force of metal to polymer

    Science.gov (United States)

    Ohshima, Masahiro; Tsubouchi, Kensuke; Ishihara, Shota; Hikima, Yuta; Tengsuwan, Siwach

    2016-03-01

    The aqueous plating solution cannot be diffused into a plain polypropylene (PP) substrate and consequently Ni-P metal layer cannot be formed by electroless plating on the PP substrate with a satisfied degree of adhesive force unless the hydrophilicity of the substrate surface was increased. A block copolymer PP-b-polyethylene oxide (PP-b-PEO) was used to increase the hydrophilicity of the surface and the adhesive force of the metal layer to the satisfactory level. Our previous study showed the morphology of PP-b-PEO domain near the surface of substrate strongly affected the adhesiveness of the metal layer to the substrate. The degrees of elongation and orientation of the PP-b-PEO domains in PP matrix were the key factors of determining the thickness of the metal-PP composite layer and the resulting adhesive strength. In this study, the effect of injection molding condition on the degrees of elongation and orientation was investigated: PP/PP-b-PEO blend substrates were prepared by injection molding at different injection speed. The higher injection speed increased the degrees of elongation and orientation of copolymer and formed multilayered structure of the copolymer domains. It could produce the electroless plating PP substrate with the higher adhesive strength of the Ni-P metal layer to the PP substrate.

  8. Electromagnetic properties of core–shell particles by way of electroless Ni–Fe–P alloy plating on flake-shaped diatomite

    International Nuclear Information System (INIS)

    Flake-shaped diatomite particles coated by Ni–Fe–P alloy were prepared by electroless plating technique and processed by heat treatment. The samples were characterized by SEM, EDS and XRD. The results indicated that the magnetic diatomite particles had continuous and homogeneous Ni–Fe–P coating, and the phase constitution of the Ni–Fe–P coating was transformed from an amorphous structure to a crystalline structure during heat treatment. The measured electromagnetic parameters and the calculated reflection loss suggested that heat treatment was able to enhance the microwave absorption performance of the paraffin wax based composites. In a word, the Ni–Fe–P coated diatomite particle obtained in this paper is a promising candidate for lightweight microwave absorbing inclusions. - Highlights: • We used the flake-shaped diatomite particles as forming template to fabricate the core–shell ferromagnetic particles. • The diatomite particles were deposited Ni–Fe–P alloy by way of electroless plating methods. • The coated diatomite particles were lightweight ferromagnetic fillers. • The composites containing coated diatomite particles with heat treatment exhibited great potential in the field of electromagnetic absorbing

  9. Structure and 57Fe conversion electron M(o)ssbauer spectroscopy study of Mn-Zn ferrite nanocrystal thin films by electroless plating in aqueous solution

    Institute of Scientific and Technical Information of China (English)

    SUN JianRong; WANG XueWen; LIU JinHong; WANG JianBo; LI FaShen

    2008-01-01

    Mn1-xZnxFe2O4 thin films with various Zn contents and of different thickness were synthesized on glass substrates directly by electroless plating in aqueous solution at 90℃ without heat treatment. The Mn-Zn ferrite films have a single spinel phase structure and well-crystallized columnar grains growing per-pendicularly to the substrates. The results of conversion electron 57Fe Mossbauer spectroscopy (CEMS) indicate that the cation distribution of Mn-xZnxFe2O4 ferrite nanocrystal thin films fabricated by elec-troless plating is different from the bulk materials' and a great quantity of Fe3+ ions are still present on A sites for x>0.5. When the Zn content of the films increases, Fe3+ ions in the films transfer from A sites to B sites and the hyperfine magnetic field reduces, suggesting that Zn2+ has strong chemical affinity towards the A sites. On the other side, with the increase of the thickness of the films, Fe3+ ions, at B sites in the spinel structure, increase and the array of magnetic moments no longer lies in the thin film plane completely. At x=0.5, Hc and Ms of Mn1-xZnxFe2O4 thin films show a minimum of 3.7 kA/m and a maximum of 419.6 kA/m, respectively.

  10. Ultrasonic preparation of nano-nickel/activated carbon composite using spent electroless nickel plating bath and application in degradation of 2,6-dichlorophenol.

    Science.gov (United States)

    Su, Jingyu; Jin, Guanping; Li, Changyong; Zhu, Xiaohui; Dou, Yan; Li, Yong; Wang, Xin; Wang, Kunwei; Gu, Qianqian

    2014-11-01

    Ni was effectively recovered from spent electroless nickel (EN) plating baths by forming a nano-nickel coated activated carbon composite. With the aid of ultrasonication, melamine-formaldehyde-tetraoxalyl-ethylenediamine chelating resins were grafted on activated carbon (MFT/AC). PdCl2 sol was adsorbed on MFT/AC, which was then immersed in spent electroless nickel plating bath; then nano-nickel could be reduced by ascorbic acid to form a nano-nickel coating on the activated carbon composite (Ni/AC) in situ. The materials present were carefully examined by Fourier transform infrared spectroscopy, X-ray diffraction, field emission scanning electron microscopy, X-ray photoelectron spectroscopy and electrochemistry techniques. The resins were well distributed on the inside and outside surfaces of activated carbon with a size of 120 ± 30 nm in MFT/AC, and a great deal of nano-nickel particles were evenly deposited with a size of 3.8 ± 1.1 nm in Ni/MFT. Moreover, Ni/AC was successfully used as a catalyst for ultrasonic degradation of 2,6-dichlorophenol. PMID:25458692

  11. Electromagnetic properties of core–shell particles by way of electroless Ni–Fe–P alloy plating on flake-shaped diatomite

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Deyuan [Bionic and Micro/Nano/Bio Manufacturing Technology Research Center, School of Mechanical Engineering and Automation, Beihang University, Beijing 100191 (China); Yuan, Liming, E-mail: lming_y@163.com [Bionic and Micro/Nano/Bio Manufacturing Technology Research Center, School of Mechanical Engineering and Automation, Beihang University, Beijing 100191 (China); Lan, Mingming; Hu, Yanyan; Cai, Jun [Bionic and Micro/Nano/Bio Manufacturing Technology Research Center, School of Mechanical Engineering and Automation, Beihang University, Beijing 100191 (China); Zhang, Wenqiang [College of Engineering, China Agricultural University, Beijing 100083 (China); Li, Haiyang [China Aerospace Science and Technology Corporation, Beijing 100854 (China)

    2013-11-15

    Flake-shaped diatomite particles coated by Ni–Fe–P alloy were prepared by electroless plating technique and processed by heat treatment. The samples were characterized by SEM, EDS and XRD. The results indicated that the magnetic diatomite particles had continuous and homogeneous Ni–Fe–P coating, and the phase constitution of the Ni–Fe–P coating was transformed from an amorphous structure to a crystalline structure during heat treatment. The measured electromagnetic parameters and the calculated reflection loss suggested that heat treatment was able to enhance the microwave absorption performance of the paraffin wax based composites. In a word, the Ni–Fe–P coated diatomite particle obtained in this paper is a promising candidate for lightweight microwave absorbing inclusions. - Highlights: • We used the flake-shaped diatomite particles as forming template to fabricate the core–shell ferromagnetic particles. • The diatomite particles were deposited Ni–Fe–P alloy by way of electroless plating methods. • The coated diatomite particles were lightweight ferromagnetic fillers. • The composites containing coated diatomite particles with heat treatment exhibited great potential in the field of electromagnetic absorbing.

  12. Study of silver activating solution used in PCB electroless copper plating%银活化液在PCB化学镀铜的研究

    Institute of Scientific and Technical Information of China (English)

    杨琼; 陈世荣; 汪浩; 曹权根; 王恒义; 谢金平; 范小玲

    2013-01-01

    文章简述了印制电路板孔金属化用的各种钯活化液的原理和特点,提出了一种银活化液,并将其催化活性和催化效果与胶体钯进行了对比。结果表明银活化用于化学镀铜,诱导时间快,可以节约成本。%This paper describes the principles and characteristics of various PCB plated through hole palladium activating solution, we propose a silver activation solution and its catalytic activity and catalytic effects were compared with colloidal palladium. The results show that silver activation solution can quickly induce electroless copper plating, and save production cost.

  13. Modeling of Auto-Catalytic Halogen Release and Ozone Depletion in Polar Regions

    International Nuclear Information System (INIS)

    This article concerns the modeling of the tropospheric ozone depletion event in polar spring where the aim is an improved understanding of the underlying physical and chemical processes. For this purpose, a model based on OpenFOAM 1.7.1 is developed, where two-dimensional compressible Navier-Stokes equations are solved numerically by finite volume method to predict the effects of turbulent mixing, advection of the fluid, and detailed chemical reactions. The present chemical reaction mechanism consists of 53 chemical reactions among 33 species to model the auto-catalytic process considering halogen species X, X2, XY, XO, HOX, where X and Y denote halogen atoms - here Br is studied. Large eddy simulation is applied to account for the turbulence and the Smagorinsky model is employed as sub-grid model. Good agreement with literature and experimental data is obtained for the profiles of the chemical species. In particular, the correct time scale of the phenomenon is captured. It is confirmed that the mixing ratio of ozone in the troposphere drops to a value near zero within several days. Moreover, it is shown that the well-mixed air is confined inside the boundary layer. A parameter study shows that the ozone depletion event happens even at reduced initial values of molecular bromine. Also, the study of coupled transport and chemistry shows that the turbulent mixing enhances the ozone depletion in the lowest layer above the earth's surface.

  14. Potentiodynamic studies of Ni-P-TiO2 nano-composited coating on the mild steel deposited by electroless plating method

    Science.gov (United States)

    Uttam, Vibha; Duchaniya, R. K.

    2016-05-01

    Now a days, corrosion studies are important for reducing the wastage of metals. The importance of corrosion studies is two folds i.e. first is economic, including the reduction of material losses resulting from the wasting away or sudden failure of materials and second is conservation Electroless process is an autocatalytic reduction method in which metallic ions are reduced in the solution. Nanocomposite coatings of Ni-P-TiO2 on mild steel are deposited by varying volume of TiO2 nano-powder by electroless method from Ni-P plating bath containing Nickel Sulphate as a source of nickel ions, sodium hypophosphite as the reducing agent, lactic acid as a complexing agents and TiO2 nano powder. Electroless Ni-P-TiO2 coating have been widely used in the chemical process industries, mechanical industries, electronic industries and chloroalkali industries due to their excellent corrosion with mechanical properties. In the present work, deposition of Ni-P alloy coating and Ni-P-TiO2 nanocomposited coatings were done on the mild steel and corrosion properties were studied with Potentio-dynamic polarization measurements method in 3.5 wt% sodium chloride solution. It showed in the experiments that Ni-P-TiO2 nanocomposited coating has better corrosion resistance as comparedthan Ni-P alloy coating. Morphological studies were done by field emission scanning electron microscopy (FESEM), energy-dispersive analysis of X-ray (EDAX) and X-ray diffraction (XRD). These studies confirmed the deposition of Ni-P alloy coating and Ni-P-TiO2 nanocomposited coating.

  15. Effect of plating conditions for electroless Ni deposition on catalytic properties of K2MoO4/Ni-SiO2 catalyst

    International Nuclear Information System (INIS)

    Highlights: ► The optimum plating condition was explored for the preparation of Ni-SiO2 support. ► The pH value of plating bath and the plating temperature were two important factors. ► Ni-SiO2 support could improve the surface morphology of the catalyst. ► The interaction between Mo species and the Ni-SiO2 precursor was strengthened. ► Catalyst-C could show superior catalytic performance. - Abstract: A series of K2MoO4/Ni-SiO2 catalysts with Ni-SiO2 as support for methanethiol synthesis from H2S-rich synthesis gas were prepared and characterized by BET, ESR, XPS and HRTEM techniques. The optimum electroless plating condition was explored for the preparation of Ni-SiO2 support. Physicochemical characterization results show that the Ni-SiO2 support prepared under the alkaline condition and relatively high plating temperature makes molybdenum species dispersing more uniformly, leading to an appropriate K/Mo atomic ratio on its surface owing to the advantage of surface morphology. The sulfurized catalyst was found to have a suitable pore diameter distribution and a suitable molar ratio of S22−/S2− (close to 1) on the surface of the catalyst, which were confirmed to be in favor of the improvement of the catalytic performance of the catalyst.

  16. Fabrication of glass/Ni-Fe-P ternary alloy core/shell composite hollow microspheres through a modified electroless plating process

    Science.gov (United States)

    An, Zhen-guo; Zhang, Jing-jie; Pan, Shun-long

    2008-12-01

    Glass/Ni-Fe-P ternary alloy core/shell composite hollow microspheres were fabricated by a modified electroless plating process. In the process, a coupling procedure was employed with 3-aminopropyltriethoxy silane as the coupling agent and silver nitrate was used as the activator. The effect of process parameters, such as mole ratio of (NH 4) 2Fe(SO 4) 2/NiSO 4, pH value of the plating solution and reaction temperature, on plating rate and properties of the composite microspheres were investigated. The results showed that the coupling treatment could improve the uniformity of Ni-Fe-P deposits remarkably. The plating rate was reduced rapidly with the increase of mole ratio of (NH 4) 2Fe(SO 4) 2/NiSO 4. The increase of the pH value could enhance the plating rate and the percentage of iron in the deposits. The as-obtained microspheres were magnetically soft at room temperature and their magnetic properties got better with the enhancement of the percentage of iron in the deposits.

  17. Development of nickel membranes deposited on ceramic materials by electroless plating: studies of the hydrogen perm-selectivity properties at elevated temperatures

    International Nuclear Information System (INIS)

    The main objective of this work was to synthesize nickel based membranes by electroless plating on materials such as alumina-α, alumina-γ and zirconia with various textures and to determine their hydrogen perm-selectivity at high temperatures. The synthesis of metal films of high purity (≥ 99% mass Ni) resulting from the choice of hydrazine with its dual role of reducing and complexing agent has revealed that the diameter of pores on the surface support has an impact on the quality of metal adherence. The various contributions of hydrogen transport through these composite membranes at low temperatures (Knudsen and surface diffusion) and at high temperatures (Knudsen and activated diffusion) was established. At its implementation in a membrane reactor (reaction of propane dehydrogenation), the layer of nickel showed a very good resistance to coking. (author)

  18. Electroless plating of low-resistivity Cu–Mn alloy thin films with self-forming capacity and enhanced thermal stability

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Sung-Te, E-mail: stchen@mail.hust.edu.tw [Department of Electronic Engineering, Hsiuping University of Science and Technology, Dali 412, Taichung, Taiwan (China); Chen, Giin-Shan [Department of Materials Science and Engineering, Feng Chia University, Seatwen 407, Taichung, Taiwan (China)

    2015-11-05

    Previous studies have typically used sputter deposition to fabricate Cu–Mn alloy thin films with concentrated solute additions which have exceeded several atomic percentages, and the electrical resistivity values of the resultant films from previous studies are relatively high, ranging from 2.5 to 3.5 μΩ-cm. Herein, we proposed a different approach by using electroless process to plate dilute Cu–Mn (0.1 at.%) alloy thin films on dielectric layers (SiO{sub 2}). Upon forming-gas annealing, the Mn incorporated into Cu–Mn films was segregated toward the SiO{sub 2} side, eventually converting itself into a few atomic layer thickness at the Cu/SiO{sub 2} interface, and forming films with a low level of resistivity the same as that of pure Cu films (2.0 μΩ-cm). The interfacial layer served as not only a diffusion barrier, but also an adhesion promoter that prevented the film’s agglomeration during annealing at elevated temperatures. The mechanism for the dual-function performance by the Mn addition was elucidated by interfacial bonding analysis, as well as dynamic (adhesive strength) and thermodynamic (surface-tension) measurements. - Highlights: • Electroless plating is proposed to grow dilute (0.1%) Cu–Mn films on SiO{sub 2} layers. • Adequate annealing results in a self-forming of MnO{sub x} at the Cu/SiO{sub 2} interface. • The role of interfacial MnO{sub x} as a barrier and adhesion promoter is demonstrated. • The treated dilute film has a low ρ level of pure Cu, in contrast to concentrated films. • Its potential as a single entity replacement of Cu interconnect is presented.

  19. Phytic acid activation prior to electroless nickel plating on magnesium alloy%镁合金化学镀镍前植酸活化工艺

    Institute of Scientific and Technical Information of China (English)

    王娟; 丁毅; 尹明勇; 马立群

    2012-01-01

    通过植酸活化可提高AZ31镁合金化学镀层的耐蚀性能.采用正交试验优化植酸活化工艺,利用金相显微镜观察了植酸膜的微观形貌,测定了植酸膜在质量分数为3.5%的NaCl溶液中的极化曲线及在化学镀镍液中的开路电位.结果表明,当植酸质量浓度为20 g/L、温度为50 ℃、pH=8时处理25 min,植酸膜具有良好的耐蚀性能,并且能够作为化学镀的活化层.%The corrosion resistance of AZ31 magnesium alloy can be improved by phytic acid activation. The phytic acid activation process was optimized through orthogonal test. The micro-morphology of phytic acid coating was observed by metallographic microscope, and its polarization curve in 3.5wt% NaCl solution and open circuit potential in electroless nickel plating bath were measured. The results showed that the phytic acid coating obtained with phytic acid 20 g/L at 50 ℃ and pH 8 for 25 min has good corrosion resistance and can be used as an activated layer for electroless nickel plating.

  20. Effects of Mm(NiCoAlMn)5 hydrogen storage alloy coated with Ni-Co-P alloy by electroless plating on electrochemical properties of hydride electrodes

    Institute of Scientific and Technical Information of China (English)

    孙春文; 郭占成; 唐致远; 郭鹤桐

    2003-01-01

    The effect of chemical plating with Ni-Co-P alloy on the properties of MH electrodes is investigated. The results show that the efficiency of storage alloy and the activation of MH electrode have been improved by introducing 1.74% cobalt in the Ni-Co-P alloy coating. The initial discharge capacity is 208 mAh/g. The maximum discharge capacity gets to 298.5 mAh/g. At the same time the cycle life of MH electrodes is improved. The discharge capacity of MH electrodes coated with Ni-Co-P is 88% of the maximum discharge capacity after 300 cycles. Whereas the discharge capacity of bare alloy electrodes retains 62% of the maximum capacity after 300 cycles. An increment of discharge capacity is mainly due to the superposition of the oxidation current of Co as well as improved efficiency of microcurrent collection. The effect of Ni-Co-P alloy coating by electroless plating on the kinetic properties of hydride electrode has been systematically investigated by electrochemical techniques. The results indicate that the kinetic properties of MH electrodes, including exchange current density, limiting current density, have been improved markedly. This improvement of kinetic properties leads to the decrease of the overpotential of anodic and cathodic polarization.

  1. Synthesis and characterization of LiNi0.49Mn1.49Y0.02O4@Ag by electroless plating technique

    International Nuclear Information System (INIS)

    Highlights: • LiNi0.49Mn1.49Y0.02O4 cathode materials have been synthesized by citric acid-assisted combustion method. • LiNi0.49Mn1.49Y0.02O4@Ag cathode materials with 4 wt% silver in Ag0 state coating layer on the surface of LiNi0.49Mn1.49Y0.02O4 have been prepared by electroless plating technique. • The Ag-coating improves the electronic conductivity and the surface stability of LiNi0.49Mn1.49Y0.02O4. • LiNi0.49Mn1.49Y0.02O4@Ag exhibit enhanced cycling stability and rate capability. - Abstract: Silver (Ag) coated LiNi0.49Mn1.49Y0.02O4 (LiNi0.49Mn1.49Y0.02O4@Ag) was prepared by electroless plating method. The microstructure, surface morphology and electronic conductivity of LiNi0.49Mn1.49Y0.02O4@Ag were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and electronic conductivity tests. The results showed that 4 wt% silver was tightly coated in Ag0 state on the surface of LiNi0.49Mn1.49Y0.02O4 to form a uniform Ag-coating layer of about 30 nm. Electrochemical tests stated clearly that the cycling performance of LiNi0.49Mn1.49Y0.02O4@Ag was more stable and the rate capability was more outstanding than that of LiNi0.49Mn1.49Y0.02O4 due to the coating of Ag on the surface of LiNi0.49Mn1.49Y0.02O4 by improving the electronic conductivity, preventing LiNi0.49Mn1.49Y0.02O4 from being attacked by electrolyte, decreasing the electrochemical polarization during cycling and increasing the lithium ion diffusion coefficient on cathode materials

  2. The evolution and analysis of electrical percolation threshold in nanometer scale thin films deposited by electroless plating

    International Nuclear Information System (INIS)

    Research highlights: → The evolution of percolation threshold in electroless deposited Ag and Cu thin films was studied and ELD as a method for controllable percolation was analyzed. → It was observed that Ag and Cu thin films reach percolation threshold at the thicknesses of 35 nm and 30 nm, respectively. → It has been shown that the film resistivity varies according to power law. The critical exponents of 0.95 and 1.04 for Ag and Cu, respectively, were extracted. - Abstract: Extension of Ultra Large Scale Integration (ULSI) to a nanometer scale elevates the importance of interconnect resistivity in addition to conventional problems of coverage and electromigration. In this work we study electrical properties of ultra thin silver (Ag) and copper (Cu) films prepared by electroless deposition (ELD) in order to provide low resistivity, stable interconnect metallization technology and electrical contacts. The thin film is modeled by assuming metal conducting clusters separated by empty dielectric gaps. The continuity of the film or gap size is controlled by film thickness with respect to the growth mode of each metal. Analysis of the electrical properties of thin films at percolation threshold demonstrates that insulator-conductor transition occurs at the thickness about 35 nm and 30 nm for Ag and Cu films, respectively. At these thicknesses film roughness is constant, therefore, scattering on film walls remains unaffected and resistivity change can be associated with a percolation mechanism. The resistivity as a function of thickness varies according to power law and reaches saturation value of 2.5 μΩ cm and 4.3 μΩ cm at the thicknesses of 60 nm and 50 nm with critical exponents (τ) of 0.95 and 1.04 for Ag and Cu thin films, respectively. The X-ray Photoelectron Spectroscopy analysis has not detected contaminations or oxidation states. The strong dependence of the film surface roughness on metal ion concentration in solution was observed while the

  3. The evolution and analysis of electrical percolation threshold in nanometer scale thin films deposited by electroless plating

    Energy Technology Data Exchange (ETDEWEB)

    Sabayev, V., E-mail: vadimsab@eng.tau.ac.il [Department of Physical Electronics, Faculty of Engineering, Tel Aviv University Ramat Aviv, Tel Aviv 69978 (Israel); Croitoru, N.; Inberg, A.; Shacham-Diamand, Y. [Department of Physical Electronics, Faculty of Engineering, Tel Aviv University Ramat Aviv, Tel Aviv 69978 (Israel)

    2011-05-16

    Research highlights: {yields} The evolution of percolation threshold in electroless deposited Ag and Cu thin films was studied and ELD as a method for controllable percolation was analyzed. {yields} It was observed that Ag and Cu thin films reach percolation threshold at the thicknesses of 35 nm and 30 nm, respectively. {yields} It has been shown that the film resistivity varies according to power law. The critical exponents of 0.95 and 1.04 for Ag and Cu, respectively, were extracted. - Abstract: Extension of Ultra Large Scale Integration (ULSI) to a nanometer scale elevates the importance of interconnect resistivity in addition to conventional problems of coverage and electromigration. In this work we study electrical properties of ultra thin silver (Ag) and copper (Cu) films prepared by electroless deposition (ELD) in order to provide low resistivity, stable interconnect metallization technology and electrical contacts. The thin film is modeled by assuming metal conducting clusters separated by empty dielectric gaps. The continuity of the film or gap size is controlled by film thickness with respect to the growth mode of each metal. Analysis of the electrical properties of thin films at percolation threshold demonstrates that insulator-conductor transition occurs at the thickness about 35 nm and 30 nm for Ag and Cu films, respectively. At these thicknesses film roughness is constant, therefore, scattering on film walls remains unaffected and resistivity change can be associated with a percolation mechanism. The resistivity as a function of thickness varies according to power law and reaches saturation value of 2.5 {mu}{Omega} cm and 4.3 {mu}{Omega} cm at the thicknesses of 60 nm and 50 nm with critical exponents ({tau}) of 0.95 and 1.04 for Ag and Cu thin films, respectively. The X-ray Photoelectron Spectroscopy analysis has not detected contaminations or oxidation states. The strong dependence of the film surface roughness on metal ion concentration in solution

  4. Ultrasonic enhanced electroless copper plating on microporous polyurethane foam%微孔聚氨酯泡沫超声强化化学镀铜的研究

    Institute of Scientific and Technical Information of China (English)

    田庆华; 郭学益

    2011-01-01

    为研制金属泡沫材料电沉积制备所需的导电泡沫基体,以孔径为0.3mm的微孔聚氨酯泡沫为基体进行化学镀铜新工艺研究.探讨镀液组成、温度、pH及超声强化对化学镀铜工艺的影响,得出化学镀铜优化工艺条件如下:硫酸铜质量浓度为16g/L,酒石酸钾钠质量浓度为30 g/L,Na2EDTA质量浓度为20g/L,α,α'-联吡啶质量浓度为25 mg/L,亚铁氰化钾质量浓度为25 mg/L,PEG-1000质量浓度为1g/L,甲醛含量为5mL/L,镀液pH为12.5~13.0,温度为50℃.在此条件下,镀液稳定性好,镀层光亮平整,镀速可达0.102 mg/min;超声强化可有效提高镀速20%~30%;化学镀铜后的导电泡沫基体经电沉积工艺可制备得到孔隙率为92.2%的三维网状金属泡沫材料.%In order to get good conductive foam substrates for foam metal materials, a novel method for electroless copper plating on microporous polyurethane foam with diameter of 0.3 mm was proposed. The main factors affecting the plating rate such as the solution composition, temperature, pH and adding ultrasonic were investigated comprehensively.The results show that the optimal conditions are 16 g/L CuSO4, 5 mL/L HCHO, 30 g/L NaKC4H4O6, 20 g/L Na2EDTA,25 mg/L α,α′-Dipyridyl, 25 mg/L K4Fe(CN)6, 1 g/L PEG-1000, at pH 12.5-13.0, temperature 50 ℃. Under above conditions, the process has efficient bath stability with the plating rate up to 0.102 mg/min. The result shows that adding ultrasonic on the process can elevate the plating rate of copper by 20%-30%. Foam metal material with a porosity of 92.2%, and a three-dimensional network structure can be fabricated by electrodeposition after electroless copper plating.

  5. Electroless Silver Plating on Hollow Glass Microsphere Modified by Silane Coupling Agent%空心玻璃微珠偶联化学镀银的研究

    Institute of Scientific and Technical Information of China (English)

    朱国庆; 文力; 张辉

    2012-01-01

    Surface of hollow glass microsphere was firstly modified by silane coupling agent, and then applying electroless silver plating directly. Surface morphology and structure of the coating were characterized by FTIR, SEM and XRD techniques. Results showed that compared with the colloidal palladium activation and silver ammonium solution activation methods, this silane coupling method could result in a uniform and compact coating with superior conductivity, higher adhesion and better silver utilization.%使用氨丙基三乙氧基硅烷偶联剂改性空心玻璃微珠表面,然后直接实施化学镀银,借助红外光谱、扫描电镜和X-射线衍射测试手段对偶联改性效果、镀层表面形貌和结构进行了表征.测试结果表明,与胶体钯活化法和硝酸银活化法化学镀银相比,空心玻璃微珠偶联表面改性直接化学镀银的镀层更为致密、均匀,银利用率高,导电性好,结合力强.

  6. Complete filling of 41 nm trench pattern using Cu seed layer deposited by SAM-modified electroless plating and electron-beam evaporation

    International Nuclear Information System (INIS)

    To overcome the limitation of the sputtered Cu seed layer in electroplating of Cu interconnects imposed by the shadow effect, a new method for depositing a Cu seed layer on a 41 nm trench pattern based on combination of electroless plating (ELP) and electron-beam (E-Beam) evaporation was developed. A Cu seed layer formed by ELP alone was too thin to be used for electroplating due to its high resistivity. To solve this problem, an additional Cu layer was deposited on top of the trench by E-Beam evaporator to enhance the electrical conductivity of the Cu seed layer. The electrical resistivity of the resulting Cu layer was reduced to 4.8 μΩ cm, which was sufficient for the conductive seed layer for electroplating the 41 nm trench pattern. The gap-filling capability also improved and there were no voids or seams in the 41 nm trench pattern. The proposed method can be an effective solution for fabrication of a conductive seed layer to fill a 41 nm trench pattern by electroplating.

  7. Enhanced electrochemical performance and carbon anti-coking ability of solid oxide fuel cells with silver modified nickel-yttrium stabilized zirconia anode by electroless plating

    Science.gov (United States)

    Wu, Xiaoyan; Tian, Yu; Zhang, Jun; Zuo, Wei; Kong, Xiaowei; Wang, Jinghui; Sun, Kening; Zhou, Xiaoliang

    2016-01-01

    In this paper, silver (Ag) particles are introduced into the conventional Ni/YSZ anode by utilizing electroless plating method to improve its carbon anti-coking ability in hydrocarbons. The experimental results show that electrochemical performances of the decorated cells in H2, CH4 and C2H6 are all increased as compared to the cell with unmodified Ni/YSZ anode, which are verified by impedance spectrums as well. The durability experiment is carried out for as long as 24 h at the current density of 0.33 A/cm2 where the modified anode is subjected to dry C2H6 indicating the anti-coking ability of the anode is greatly improved. Scanning electron microscope shows that the slight decreasing in the cell terminal voltage can be attributed to the minimized carbon deposition which maybe resulted from the aggregation of silver particles at high temperature. Energy-dispersive X-ray spectroscopy line scanning results after long-term stability operation of the anode suggest that the carbon deposition can be depressed effectively both inside the anode and on the surface of the anode. Therefore, the results show that silver is a promising candidate material for modifying the Ni/YSZ anode with regard to improving electrochemical performance and suppressing the carbon deposition when taking the hydrocarbons as fuels.

  8. SiC颗粒表面化学镀铜镀液工艺参数的优化设计%Optimization design of solution for electroless copper plating on the surface of SiC particle

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    In order to improve the wettability between the metal matrix and ceramic particle,the electroless copper plating technology was used to treat the SiC particle for improving the interface bonding capacity. The orthogonal design method was utilized to optimize plating parameters and the effect of solution parameters on the weight gain rate of SiC particle was discussed. The experimental results show that the weight gain rate of SiC particle increases after electroless copper plating when the concentration of CuSO4 and CH3CHO increases,while the weight gain rate gradually reduces with the concentration increase of the chelating agent. The homogeneous plating layers on the SiC particle can be obtained after the parameters optimization of electroless copper plating.%  针对金属基体与陶瓷颗粒之间润湿性差的问题,采用化学镀铜对SiC颗粒进行表面改性,试图提高其界面结合能力。采用正交试验方法优化化学镀铜参数,探讨镀液参数对复合粉体质量增加效果的影响。研究表明:化学镀铜过程中,随着硫酸铜浓度和甲醛浓度增加,镀后复合粉体质量增加率增加;随着络合剂浓度增加,质量增加率逐渐降低;化学镀铜参数优化后可实现SiC粉体表面化学镀铜层的均匀镀覆。

  9. Synthesis and characterization of LiNi0.49Mn1.49Y0.02O4@Ag by electroless plating technique

    Science.gov (United States)

    Xiong, Lizhi; Liu, Wenping; Wu, Yuxian; He, Zeqiang

    2015-02-01

    Silver (Ag) coated LiNi0.49Mn1.49Y0.02O4 (LiNi0.49Mn1.49Y0.02O4@Ag) was prepared by electroless plating method. The microstructure, surface morphology and electronic conductivity of LiNi0.49Mn1.49Y0.02O4@Ag were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and electronic conductivity tests. The results showed that 4 wt% silver was tightly coated in Ag0 state on the surface of LiNi0.49Mn1.49Y0.02O4 to form a uniform Ag-coating layer of about 30 nm. Electrochemical tests stated clearly that the cycling performance of LiNi0.49Mn1.49Y0.02O4@Ag was more stable and the rate capability was more outstanding than that of LiNi0.49Mn1.49Y0.02O4 due to the coating of Ag on the surface of LiNi0.49Mn1.49Y0.02O4 by improving the electronic conductivity, preventing LiNi0.49Mn1.49Y0.02O4 from being attacked by electrolyte, decreasing the electrochemical polarization during cycling and increasing the lithium ion diffusion coefficient on cathode materials.

  10. Direct electroless nickel plating on magnesium alloys and deposit properties%镁合金直接化学镀镍工艺及镀层性能

    Institute of Scientific and Technical Information of China (English)

    刘海萍; 夏文超; 毕四富; 李宁

    2011-01-01

    The optimal process conditions for direct electroless nickel plating on AZ31D magnesium alloy are as follows: nickel sulfate 14-22 g/L, sodium hypophosphite 20-28 g/L, citric acid 5-7 g/L, sodium acetate 9-17 g/L,ammonium hydrogen fluoride 8 g/L, hydrofluoric acid (volume fraction 40%) 12 mL/L, thiourea 2 mg/L, pH 6.2-6.4(adjusted with ammonia water), temperature 75-85 ℃ and deposition time 10-60 min. Under the given conditions, the deposit has the features of good appearance, strong adhesion to magnesium alloy substrate, high corrosion resistance, phosphorus content of 6%-10% and fast deposition rate.%AZ31D镁合金上直接化学镀镍的较佳工艺条件为:硫酸镍14~22g/L,次磷酸钠20~28 g/L,柠檬酸5~7 g/L,乙酸钠9~17 g/L,氟化氢铵8 g/L,40%(体积分数)的氢氟酸12 mL/L,硫脲2 mg/L,pH(用氨水调节)6.2~6.4,温度75~85℃,时间10~60 min.在此条件下获得的化学镀镍层外观良好,磷含量为6%~10%(质量分数),与镁合金基体结合牢固,耐蚀性能好且沉积速率较快.

  11. Development of nanoscale Ni-embedded single-wall carbon nanotubes by electroless plating for transparent conductive electrodes of 375 nm AlGaN-based ultraviolet light-emitting diodes

    Science.gov (United States)

    Park, Jun-Beom; Park, Hyung-Jo; Bae, Hyojung; Jeong, Tak; Han, Jong-Hun; Kwak, Joon Seop; Ha, Jun-Seok

    2016-08-01

    We propose a nanoscale Ni-embedded single-wall carbon nanotube (SWCNT) composite for transparent conductive electrodes (TCEs) of AlGaN-based ultraviolet light-emitting diodes (UV LEDs). TCEs specifically for the ultraviolet region were developed using Ni selectively electroless-plated SWCNTs. The nanoscale Ni of TCEs improved electrical conductivity and formed ohmic contact with p-GaN while minimizing transmittance loss. We applied Ni-embedded SWCNTs, SWCNTs, and Ni/Au to the TCEs of 375 nm UV LEDs. UV LEDs with Ni-embedded SWCNTs showed a 32% higher output power than UV LEDs with conventional Ni/Au TCEs.

  12. N,O-羧甲基壳聚糖在导电涤纶织物化学镀中的应用%Application of N,O-carboxymethyl chitosan in conductive polyester fabrics with electroless plating treatment

    Institute of Scientific and Technical Information of China (English)

    吴建文; 俞丹; 王炜

    2011-01-01

    对壳聚糖引入羧基制备改性N,O-羧甲基壳聚糖(NOCC),因其有良好的水溶性,可采用浸轧法处理在涤纶织物上,利用其在活化过程中吸附贵金属钯引发之后的化学镀,获得致密、均匀的金属镀层,赋予织物导电性和电磁屏蔽效能.采用红外图谱(FT-IR)和1℃核磁共振谱图对NOCC进行表征,并用SEM图观察了经NOCC处理后和化学镀后导电涤纶织物的纤维表面形貌.%Chitosan was modified with carboxyl to produce N,O-carboxymethyl chitosan (NOCC). Due to good water solubility, NOCC was treated on the polyester (PET) fabrics through padding method, which adsorbed precious palladium metal in the activation process and catalyzed the electroless plating process. Accordingly, compact and even metal plating was obtained, which endowed the fabric with electrical conductivity and electromagnetic shielding property. The structure of NOCC was characterized by FT-IR and 13C-NMR. The morphology of electrical conductive polyester fabric treated by NOCC and electroless plating was observed by SEM.

  13. Process optimization of electroless copper plating and its influence on electrochemical properties of AB5-type hydrogen storage alloy

    Institute of Scientific and Technical Information of China (English)

    ZHANG

    2010-01-01

    The amount of Cu coating by chemical plating was investigated based on quadratic regression orthogonal experimental design being adapted to the variation law of temperature,pH value and Ni2+concentration,and the relevant regression equation was expressed as y=2.1609+0.5295×10-3T2-0.0342P2-0.0265N2+0.0023TP+0.0020TH+0.0199PN-0.0959T+0.3814P-0.2073N.The results showed that the deposition rate augmented with the increasing in temperature,pH value and Ni2+concentration.The experimental parameters of the optimal coating were temperature 75 ℃,pH value 8.5 and Ni2+concentration 1.2 g/L.The electrochemical tests indicated that the cycle stability increased from 60.66% to 75.58%,indicating that the treated alloy exhibited better corrosion resistance.

  14. Vapour Treatment Method Against Other Pyro- and Hydrometallurgical Processes Applied to Recover Platinum From Used Auto Catalytic Converters

    Institute of Scientific and Technical Information of China (English)

    Agnieszka FORNALCZYK; Mariola SATERNUS

    2013-01-01

    Today more and more cars are produced every year.All of them have to be equipped with catalytic converters,the main role of which is to obtain substances harmless to the environment instead of exhausted gases.Catalytic converters contain platinum group metals (PGM) especially platinum,palladium and rhodium.The price of these metals and their increasing demand are the reasons why today it is necessary to recycle used auto catalytic converters.There are many available methods of recovering PGM metals from them,especially platinum.These methods used mainly hydrometallurgical processes; however pyrometallurgical ones become more and more popular.The article presents results of the research mainly concerning pyrometallurgical processes.Two groups of research were carried out.In the first one different metals such as lead,magnesium and copper were used as a metal collector.During the tests,platinum went to those metals forming an alloy.In other research metal vapours were blown through catalytic converter carrier (grinded or whole).In the tests metals such as calcium,magnesium,cadmium and zinc were applied.As a result white or grey powder (metal plus platinum) was obtained.The tables present results of the research.Processing parameters and conclusions are also shown.To compare efficiency of pyrometallurgical and hydrometallurgical methods catalytic converter carrier and samples of copper with platinum obtained from pyrometallurgical method were solved in aqua regia,mixture of aqua regia and fluoric acid.

  15. Research Progress of Conductive Composite Filler Prepared by Electroless Plating for Electromagnetic Shielding%化学镀制备电磁屏蔽用导电复合填料的研究进展

    Institute of Scientific and Technical Information of China (English)

    管登高; 孙传敏; 孙遥; 徐冠立; 林金辉; 陈善华

    2011-01-01

    The basic theory and main features about electroless plating are introduced. The situation of the research and development of metal coated conductive composite fillers with various sizes, densities, length-diameter ratios, conductivities, shielding properties and inoxidizabilities for electromagnetic shielding at home and abroad are emphatically reviewed, which are prepared using metal, inorganic nonmetallic and polymer powders as substrates by electroless plating. The advantages and disadvantages of these three types of metal coated conductive composite fillers are analyzed and compared. The main problems that exist at present such as electromagnetic impedance mismatch, low electromagnetic comprehensive performances and big surface property differences are pointed out. And the further study such as the compositions of the fillers, the technology and the formula of electroless plating are suggested in order to develop electromagnetic shielding composite fillers with higher performance-price ratios. This has very important significance and function to prevent and control electromagnetic radiation pollution.%介绍了化学镀的基本原理和主要特点,重点阐述了以金属、无机非金属、聚合物等粉料为基体,采用化学镀技术制备具有不同粒度、密度、长径比、导电性、电磁屏蔽效能和抗氧化性的电磁屏蔽用金属包覆型导电复合填料的国内外研究现状和进展.分析比较了这3类电磁屏蔽用导电复合填料的优缺点,指出其目前还存在电磁阻抗不匹配、电磁综合性能不高和表面性质差异过大的主要问题,建议今后还需进一步研究复合填料组成、化学镀配方和工艺等,以研制出性价比更高的电磁屏蔽用复合填料.

  16. Passive auto-catalytic recombiners operation in the presence of hydrogen and carbon monoxide: Experimental study and model development

    International Nuclear Information System (INIS)

    Highlights: • We studied the hydrogen conversion in the presence of carbon monoxide (CO). • CO recombines at a lower efficiency than hydrogen. • Under the given conditions, hydrogen conversion is not affected by CO. • We used three different numerical codes to simulate the experimental findings. • All codes are reproducing the experimental data well. -- Abstract: In a LWR severe accident, carbon monoxide (CO) may be generated inside the containment due to molten corium concrete interaction (MCCI). As a component of the accident atmosphere, CO will interact with passive auto-catalytic recombiners (PARs) which are installed inside LWR containments for hydrogen (H2) removal. Depending on the boundary conditions, CO may either react with oxygen to carbon dioxide (CO2) or act as catalyst poison, reducing the catalyst activity and hence the hydrogen conversion efficiency. A new experimental test programme performed in co-operation between JÜLICH and RWTH investigates these aspects aiming at providing data for model development for advanced severe accident analyses. In the first test series presented here, the parallel catalytic reaction of H2 and CO on the catalyst surface has been studied, i.e. the hydrogen recombination reaction was started before CO was injected. In total, 33 steady state measurements have been performed. The test series was jointly evaluated by JÜLICH, RWTH and IRSN. The test results show that under the given conditions the conversion of CO into CO2 has no negative impact on the parallel hydrogen conversion. The efficiency of the CO recombination in terms of molar rates is significantly smaller (by a factor of ∼2) than the corresponding H2 conversion efficiency. Due to the exothermal reaction, the parallel CO conversion may also have an impact on the possible ignition of the flammable gases at hot PAR surfaces. The authors have used three different numerical codes for the simulation of the parallel CO/H2 recombination. The codes REKO

  17. A Study of Electroless Silver Plating with Pd-Free Activation on Cenosphere%空心玻璃微珠无钯活化化学镀银的研究

    Institute of Scientific and Technical Information of China (English)

    朱国庆; 张瑾; 张辉

    2012-01-01

    基于银镜反应原理,不经过粗化和活化直接对空心玻璃微珠进行化学镀银.采用单因素分析法,研究了硝酸银、葡萄糖、装载量、氢氧化钠和无水乙醇对银的利用率以及镀层的增重率、导电性能和结合强度等的影响,并借助扫描电镜和X射线衍射仪对镀层的表面形貌和结构进行了分析.结果表明:与胶体钯活化工艺相比,无(钯)活化化学镀银工艺的银的利用率高,镀层均匀、致密,导电性好,结合强度高.%Based on the principle of silver mirror reaction, electroless silver plating was directly carried out on cenoshpere without pretreatments of coarsening and activation. The effects of silver nitrate, glucose, cenosphere loadage, sodium hydroxide and anhydrous alcohol on silver utilization ratio end the weight gain rate, conductivity, binding strength, etc. of the coating were investigated by single factor analysis. The surface morphology and structure of the coating were analyzed by SEM and XRD, The results indicate that as compared with colloidal palladium activation method, the silver utilization ratio is high, and the coating is uniform and compact with superior conductivity and high binding strength when the electroless silver plating process without palladium activation prelreatment is adopted.

  18. Electroless Fabrication of Cobalt Alloys Nanowires within Alumina Template

    Directory of Open Access Journals (Sweden)

    Nazila Dadvand

    2007-01-01

    Full Text Available A new method of nanowire fabrication based on electroless deposition process is described. The method is novel compared to the current electroless procedure used in making nanowires as it involves growing nanowires from the bottom up. The length of the nanowires was controlled at will simply by adjusting the deposition time. The nanowires were fabricated within the nanopores of an alumina template. It was accomplished by coating one side of the template by a thin layer of palladium in order to activate the electroless deposition within the nanopores from bottom up. However, prior to electroless deposition process, the template was pretreated with a suitable wetting agent in order to facilitate the penetration of the plating solution through the pores. As well, the electroless deposition process combined with oblique metal evaporation process within a prestructured silicon wafer was used in order to fabricate long nanowires along one side of the grooves within the wafer.

  19. Development of Nickel Immersion Pretreatment of Electroless Nickel Plating on Al Alloy Surface%铝基化学镀镍浸镍前处理的研究进展

    Institute of Scientific and Technical Information of China (English)

    孙硕; 宋贡生; 马正华

    2015-01-01

    铝基表面欲获得结合力好的镀层,关键在于前处理工艺的选择. 尽管浸锌法是目前研究较多、效果较好的前处理方法,但仍存在一些不足,而浸镍法可以避免这些不足,有望取代浸锌法. 较详细地阐述了浸镍法的原理及研究现状,并将文献中涉及的浸镍法分为活化浸镍、碱性预镀镍和二次浸镍. 活化浸镍液中一般不含还原剂,主要通过置换反应生成一层具有催化作用的镍,进而促使化学镀过程中镍紧密均匀地沉积;碱性预镀镍则是通过含有还原剂的镍盐溶液,在铝基表面预化学镀上一薄层镍,其原理与化学镀镍相同. 同时,对比分析了两种浸镍法及其组合处理法之间的区别与联系. 最后,指出了浸镍法未来的发展方向:其一,简化工艺,用一次浸镍法代替二次浸镍法;其二,无毒、低污染,研发出无氟浸镍液;其三,获得高性能,即优化浸镍液配方,使得镀层与基体结合强度更好.%The key line to obtain electroless nickel plating with excellent adhesion to the substrate is the pretreatment process. The zincate treatment method as a pretreatment process has been studied by many researchers, and its effect is good. However, its disadvantages cannot be ignored. The nickel immersion method can avoid these shortages, and it is expected to replace zinc immer-sion method. The present article introduced the research status and the principle of zincate treatment. At the same time, this paper divided the relative zincate treatment into activation-nickel immersion method, alkaline elctroless nickel pre-plating method, and double nickel immersion method. The solution of activation-nickel immersion method normally does not contain reducing agent. This method produces a thin layer of nickel catalyst by substitution reaction, prompting the deposition of electroless nickel plating closely and evenly in the later process. The solution of alkaline nickel pre-plating is a kind of

  20. Formation of palladium concave nanocrystals via auto-catalytic tip overgrowth by interplay of reduction kinetics, concentration gradient and surface diffusion

    Science.gov (United States)

    Su, Na; Chen, Xueying; Yue, Bin; He, Heyong

    2016-04-01

    A clear understanding of the growth mechanism involved in the shape-controlled synthesis of noble-metal nanocrystals with concave surfaces can provide useful information for the rational design of novel anisotropic nanostructures with controllable properties. In this paper, we conducted a systematic study of the detailed growth mechanism of the Pd arrow-headed tripods and revealed how the formation of the concave Pd nanocrystals was collectively controlled by the reduction kinetics, concentration gradient of Pd precursors, and surface diffusion of atoms. The formation of the arrow-headed tripods can be attributed to an auto-catalytic tip overgrowth process, where the Pd triangular nanoplate seeds formed under a suitably slow reduction rate can auto-catalyze the dehydrogenation of benzyl alcohol to generate hydrogen atoms [H]. The presence of [H] further dramatically accelerates the reduction of Pd(acac)2, which introduces a concentration gradient of Pd precursors in our non-stirring synthesis system and facilitates the kinetically-controlled tip overgrowth under a concentration gradient to form tripods with troughs on the arms. The final shapes of the concave nanocrystals depend on the relative rate of atom deposition and surface diffusion of atoms, which can be tuned by manipulating the reaction conditions such as the reaction temperature and the stirring conditions. This study presents a new possibility for the rational synthesis of various Pd nanostructures by manipulating the auto-catalytic process and tuning the relative rate of atom deposition and surface diffusion of atoms, which provides useful information for understanding the growth mechanism and the design of other anisotropic noble-metal nanostructures.

  1. Electroless alloy/composite coatings: A review

    Indian Academy of Sciences (India)

    R C Agarwala; Vijaya Agarwala

    2003-06-01

    Since the inception of electroless coating by Brenner & Riddell in 1946, it has been the subject of research interest and, in the past two decades, emphasis has shifted to the studies of its properties and applications. The co-deposition of particulate matter or substance within the growing film has led to a new generation of electroless composite coatings, many of which possess excellent wear and corrosion resistance. This valuable process can coat not only electrically conductive materials including graphite but also fabrics, insulators like plastics, rubber etc. The low coating rates with these can provide better reflectivity of plated surfaces and many more applications. Coatings can be tailored for desired properties by selecting the composition of the coating alloy/composite/metallic to suit specific requirements. The market for these coatings is expanding fast as the potential applications are on the rise. In the present article, an attempt has been made to review different electroless alloy/composite coatings with respect to bath types and their composition, properties and applications. Different characterisation studies have been conducted on various electroless nickel-based coatings with emphasis on wear and corrosion properties.

  2. Synthesis and characterization of LiNi{sub 0.49}Mn{sub 1.49}Y{sub 0.02}O{sub 4}@Ag by electroless plating technique

    Energy Technology Data Exchange (ETDEWEB)

    Xiong, Lizhi; Liu, Wenping; Wu, Yuxian; He, Zeqiang, E-mail: csuhzq@163.com

    2015-02-15

    Highlights: • LiNi{sub 0.49}Mn{sub 1.49}Y{sub 0.02}O{sub 4} cathode materials have been synthesized by citric acid-assisted combustion method. • LiNi{sub 0.49}Mn{sub 1.49}Y{sub 0.02}O{sub 4}@Ag cathode materials with 4 wt% silver in Ag{sup 0} state coating layer on the surface of LiNi{sub 0.49}Mn{sub 1.49}Y{sub 0.02}O{sub 4} have been prepared by electroless plating technique. • The Ag-coating improves the electronic conductivity and the surface stability of LiNi{sub 0.49}Mn{sub 1.49}Y{sub 0.02}O{sub 4}. • LiNi{sub 0.49}Mn{sub 1.49}Y{sub 0.02}O{sub 4}@Ag exhibit enhanced cycling stability and rate capability. - Abstract: Silver (Ag) coated LiNi{sub 0.49}Mn{sub 1.49}Y{sub 0.02}O{sub 4} (LiNi{sub 0.49}Mn{sub 1.49}Y{sub 0.02}O{sub 4}@Ag) was prepared by electroless plating method. The microstructure, surface morphology and electronic conductivity of LiNi{sub 0.49}Mn{sub 1.49}Y{sub 0.02}O{sub 4}@Ag were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and electronic conductivity tests. The results showed that 4 wt% silver was tightly coated in Ag{sup 0} state on the surface of LiNi{sub 0.49}Mn{sub 1.49}Y{sub 0.02}O{sub 4} to form a uniform Ag-coating layer of about 30 nm. Electrochemical tests stated clearly that the cycling performance of LiNi{sub 0.49}Mn{sub 1.49}Y{sub 0.02}O{sub 4}@Ag was more stable and the rate capability was more outstanding than that of LiNi{sub 0.49}Mn{sub 1.49}Y{sub 0.02}O{sub 4} due to the coating of Ag on the surface of LiNi{sub 0.49}Mn{sub 1.49}Y{sub 0.02}O{sub 4} by improving the electronic conductivity, preventing LiNi{sub 0.49}Mn{sub 1.49}Y{sub 0.02}O{sub 4} from being attacked by electrolyte, decreasing the electrochemical polarization during cycling and increasing the lithium ion diffusion coefficient on cathode materials.

  3. Coaxial metal and magnetic alloy nanotubes in polycarbonate templates by electroless deposition

    OpenAIRE

    Rohan, James F.; Casey, Declan P.; Ahern, Bernadette M.; Rhen, Fernando M.F.; Roy, Saibal; Fleming, David; Lawrence, Simon E.

    2008-01-01

    We present a novel technique for the preparation of coaxial metal and magnetic alloy nanotubes, which is demonstrated for the coaxial nanotubes of Ni/Co and Ni/CoNiFe alloys deposited in activated polycarbonate templates using electroless plating. For each metal or alloy the tube wall thickness was controlled to be less than 100 nm. The process involved two consecutive deposition steps from hypophosphite and/or borane reducing agent based electroless plating solutions. We further characterise...

  4. Fabrication of metal coated carbon nanotubes by electroless deposition for improved wettability with molten aluminum

    OpenAIRE

    Arai, Susumu; Suzuki, Yosuke; Nakagawa, Junshi; Yamamoto, Tohru; Endo, Morinobu

    2012-01-01

    Ni-P alloy coated and Au/Ni-P alloy double-coated multiwalled carbon nanotubes (MWCNTs) were fabricated using electroless plating. Three types of electroless Ni-P alloy plating baths were prepared to coat the MWCNTs with Ni-P alloy films of varying phosphorus content. Electroless gold coating of the Ni-P alloy coated MWCNTs was also carried out using a non-cyanide bath. The microstructures of the coatings on the MWCNTs were examined by scanning electron microscopy and X-ray diffraction. The w...

  5. Ultrasound influence on the activation step before electroless coating.

    Science.gov (United States)

    Touyeras, F; Hihn, J Y; Delalande, S; Viennet, R; Doche, M L

    2003-10-01

    This paper is devoted to the electroless plating of non-conductive substrates under ultrasound at 530 kHz. The ultrasonic irradiation is applied to the activation and to the plating steps. Effects are measured by following the final copper thickness obtained in 1 h of plating time, easily correlated to the average plating rate. It appears that ultrasound has a strong influence on the plating rates enhancement, and assumptions can be made that this increase could be linked to the catalyst cleaning. This is confirmed by XPS measurements. PMID:12927613

  6. Start-up behaviour of a passive auto-catalytic recombiner under counter flow conditions: Results of a first orienting experimental study

    Energy Technology Data Exchange (ETDEWEB)

    Simon, Berno, E-mail: simon@lrst.rwth-aachen.de [RWTH Aachen University, Institute for Reactor Safety and Reactor Technology (LRST), 52072 Aachen (Germany); Reinecke, Ernst-Arndt, E-mail: e.reinecke@fz-juelich.de [Forschungszentrum Jülich GmbH, Institute of Energy and Climate Research – Nuclear Waste Management and Reactor Safety (IEK-6), 52425 Jülich (Germany); Kubelt, Christian, E-mail: kubelt@lrst.rwth-aachen.de [RWTH Aachen University, Institute for Reactor Safety and Reactor Technology (LRST), 52072 Aachen (Germany); Allelein, Hans-Josef, E-mail: allelein@lrst.rwth-aachen.de [RWTH Aachen University, Institute for Reactor Safety and Reactor Technology (LRST), 52072 Aachen (Germany); Forschungszentrum Jülich GmbH, Institute of Energy and Climate Research – Nuclear Waste Management and Reactor Safety (IEK-6), 52425 Jülich (Germany)

    2014-10-15

    Highlights: • We studied the start-up behaviour of a PAR located in a downward-directed flow. • We performed several identical experiments with and without counter flow. • A temporary interference of the establishing chimney flow is observed. • An earlier local start-up of the catalytic reaction occurs under downward flow. • The overall performance of the PAR is not significantly affected. - Abstract: A downward directed wall-near flow represents a typical thermal hydraulic condition inside the LWR containment during a severe accident. In order to efficiently remove hydrogen released into the containment, passive auto-catalytic recombiners (PARs) located close to the containment wall have to establish an internal upward directed chimney flow against this counter flow. In cooperation between RWTH Aachen and the Research Center Jülich, the effect of a downward directed flow on the PAR start-up has been investigated in the REKO-4 test facility at Jülich. The test series includes experiments with identical boundary conditions performed under counter flow conditions as well as in quiescent atmosphere as reference case. Under counter flow conditions, an earlier local start-up of the catalytic reaction on the upper edge of the catalyst sheets was observed. However, the establishment of full PAR operation required more time compared to the reference case. This delay is attributed to a partial inflow of the counter flow into the PAR outlet which interferes with the establishing of a chimney flow promoted by the exothermal catalytic reaction. Once a developed chimney flow inside the PAR is established, no negative effect on the PAR performance could be observed. As expected, the counter flow mixes immediately with the PAR outlet flow dissolving the characteristic plume of hot gases at the PAR outlet.

  7. Start-up behaviour of a passive auto-catalytic recombiner under counter flow conditions: Results of a first orienting experimental study

    International Nuclear Information System (INIS)

    Highlights: • We studied the start-up behaviour of a PAR located in a downward-directed flow. • We performed several identical experiments with and without counter flow. • A temporary interference of the establishing chimney flow is observed. • An earlier local start-up of the catalytic reaction occurs under downward flow. • The overall performance of the PAR is not significantly affected. - Abstract: A downward directed wall-near flow represents a typical thermal hydraulic condition inside the LWR containment during a severe accident. In order to efficiently remove hydrogen released into the containment, passive auto-catalytic recombiners (PARs) located close to the containment wall have to establish an internal upward directed chimney flow against this counter flow. In cooperation between RWTH Aachen and the Research Center Jülich, the effect of a downward directed flow on the PAR start-up has been investigated in the REKO-4 test facility at Jülich. The test series includes experiments with identical boundary conditions performed under counter flow conditions as well as in quiescent atmosphere as reference case. Under counter flow conditions, an earlier local start-up of the catalytic reaction on the upper edge of the catalyst sheets was observed. However, the establishment of full PAR operation required more time compared to the reference case. This delay is attributed to a partial inflow of the counter flow into the PAR outlet which interferes with the establishing of a chimney flow promoted by the exothermal catalytic reaction. Once a developed chimney flow inside the PAR is established, no negative effect on the PAR performance could be observed. As expected, the counter flow mixes immediately with the PAR outlet flow dissolving the characteristic plume of hot gases at the PAR outlet

  8. Electroless plating of Ag-TiO2 nanoparticle composite on PET fabric%涤纶织物纳米TiO2颗粒化学复合镀银

    Institute of Scientific and Technical Information of China (English)

    凌明花; 张辉

    2011-01-01

    采用化学镀技术,实现了不同分散剂分散纳米TiO2颗粒涤纶织物表面化学复合镀银,借助SEM、XRD和TG对镀层表面形貌、结构和织物热性能进行研究,测试织物的电磁波屏蔽、导电、耐磨、透气和光催化性能.结果表明:用PVP&T80作分散剂时,纳米TiO2的引入对镀层结构没有影响,但晶粒尺寸增大;随着纳米TiO2质量浓度的增加,镀速先上升后降低然后再上升;当增重率相同时,较化学镀银织物,纳米TiO2化学复合镀银织物热学性能没有明显变化,耐磨性增强,透气性下降;当纳米TiO2质量浓度小于0.25 g/L时,电磁波屏蔽性能有所提高,可以降解亚甲基橙染料.%TiO2 nanoparticles were firstly dispersed by using different dispersants, and then was added to the solution of silver ammonia. The Ag-TiO2 composite coating on PET fabric was performed by electroless plating. The morphology, structure, and thermal property of the Ag-TiO2-coated fabric was characterized using SEM, EDX, XRD and TG. The electromagnetic shielding effectiveness, electrical conductivity, abrasion resistance, air permeability and degradation of methylene orange dye under UV irradiation of the fabric were investigated. It was found that the introdution of TiO2 nanoparticles had no effect on the structure of the Ag coating when PVA and Tween 80 were used as dispersant. But the crystal size increased. With the increase of the mass concentration of TiO2 nanoparticles, the plating rate increased at first, then decreased and increased at last. As compared with the Ag-plated fabric, the onset decomposition temperature of the Ag-TiO2-plated fabric did not change when the weighting percentage was identical. However, the abrasion resistance was increased and air permeability was decreased. The electromagnetic shielding effectiveness was improved when the mass concentration of TiO2 nanoparticles was below 0. 2 g/L. The capability of photocatalytic degradation of methylene

  9. Direct electroless Ni-P deposition on AM50 magnesium alloy from sulfate bath

    Institute of Scientific and Technical Information of China (English)

    LI Guang-yu; NIU Li-yuan; JIANG Zhong-hao; GU Chang-dong; LIAN Jian-she

    2006-01-01

    A bright electroless Ni-P deposition on AM50 magnesium alloy in a sulfate plating bath was proposed by using direct plating process with non-chromate pretreatment. The electroless Ni-P plating on AM50 magnesium alloy has an admirable appearance and good adhesion. The results indicate that the electroless Ni-P deposition with non-chromate pretreatment has better adhesion than that of zinc immersion coating. Anodic polarization curves indicate that the electroless Ni-P deposition obtained from the sulfate bath has similar corrosion-resistance to that obtained from basic nickel carbonate bath. The deposition process generates less pollutant by a non-chromate plating bath and is suitable for the magnesium alloys manufacture because of its low cost. The hardness of the electroless Ni-P plated AM50 is about HV 720.6 and HV 969.7 after heat treatments at 180 ℃ for 2 h. The wear resistance of Ni-P plated magnesium alloy specimens is about 5 to 9 times as high as that of bare magnesium alloys.

  10. Growth behavior of electroless copper on silicon substrate

    Institute of Scientific and Technical Information of China (English)

    Shin-Shyan Wu; Wei-Long Liu; Ting-Kan Tsai; Shu-Huei Hsieh; Wen-Jauh Chen

    2007-01-01

    The growth behavior containing deposit morphology,growth rate,activation energy,and growth mechanism of copper on silicon substrate,especially at the initial stage,in the electroless plating process was studied.Copper was deposited on the surface of the silicon substrate in an electroless plating bath containing formalin (CH2O 37vol%) as a reducing agent at a pH value of 12.5 and a temperature of 50-75 ℃.The copper deposit was characterized using a field emission scanning electron microscope and transmission electron microscope.The results showed that after the activation process,nanoscale Pd particles were distributed evenly on the surface of the silicon; in the deposition process,copper first nucleated at locations not only near the Pd particles but also between the Pd particles;the growth rate of electroless Cu ranged from 0.517 nm/s at 50 ℃ to 1.929 nm/s at 75 ℃.The activation energy of electroless Cu on Si was 52.97 kJ/mol.

  11. ELECTROLESS NICKEL DEPOSITION ON FRAXINUS MANDSHURICA VENEER MODIFIED WITH APTHS FOR EMI SHIELDING

    OpenAIRE

    Haibing Liu; Lijuan Wang

    2010-01-01

    Electroless nickel deposition was carried out on Fraxinus mandshurica veneers for EMI shielding under a new activation process. In the process, Pd(II) was absorbed on the surface of veneers modified with γ-aminopropyltrihydroxysilane (APTHS) obtained from the hydrolysis of γ-aminopropyltriethoxysilane (APTES). After the reduction, electroless plating was successfully initiated, and Ni-P coating was deposited on the veneers. The activation process and resulting coating were characterized by XP...

  12. A novel Ag catalyzation process using swelling impregnation method for electroless Ni deposition on Kevlar® fiber

    Science.gov (United States)

    Pang, Hongwei; Bai, Ruicheng; Shao, Qinsi; Gao, Yufang; Li, Aijun; Tang, Zhiyong

    2015-12-01

    A novel Ag catalyzation process using swelling impregnation pretreatment method was developed for electroless nickel (EN) deposition on Kevlar fiber. Firstly, the fiber was immersed into an aqueous dimethylsulfoxide (DMSO) solution of silver nitrate to impart silver nitrate into the inner part of the fiber near the surface. Subsequently silver nitrate was reduced to metal silver nanoparticles on the fiber surface by treatment with aqueous solution of sodium borohydride. After electroless plating, a dense and homogeneous nickel coating was obtained on the fiber surface. The silver nanoparticles formed at the fiber surface functioned as a catalyst for electroless deposition as well as an anchor for the plated layer. The study also revealed that the incorporation of surfactant sodium dodecyl sulfate (SDS) in electroless nickel plating bath can enhance the adhesion strength of EN layer with the fiber surface and minimize the surface roughness of the EN coating. The Ni plated Kevlar fiber possessed excellent corrosion resistance and high tensile strength.

  13. Preparation of copper-coated fine molybdenum powders with electroless technique

    Institute of Scientific and Technical Information of China (English)

    WANG Guang-jun; WANG De-zhi; ZHOU Jie; WU Zhuang-zhi

    2009-01-01

    The molybdenum powders with average particle size of 3 μm were coated with copper by electroless plating. The influence of pretreatment, solution composition and plating conditions on electroless copper plating was studied. The copper-coated molybdenum powders were examined by SEM and XRD. Results indicate that a series of optimization methods is used to add activated sites before electroless copper plating. Taking TEA and EDTA as chief and assistant complex agents respectively, 2,2'-bipyridyl and PEG as double stabilizers, the Mo powders are coated with copper successfully with little Cu2O contained, at the same time, Mo-Cu composite powders with copper content of 15 - 85 wt% can be obtained. The optimal values of pH, temperature and HCHO concentration are 12- 13, 60-65 ℃ and 22-26 mL/L, respectively.

  14. Preparation and electricity performance of silver coating glass frit by electroless silver plating%化学镀制备银包覆玻璃粉及其电学性能

    Institute of Scientific and Technical Information of China (English)

    杨超; 甘卫平; 周健; 黎应芬; 鲁志强; 戈田田

    2015-01-01

    Glass frits were activated through ethylene glycol reducing AgNO3, nano-silver coated glass frits composite powders were prepared by electroless plating method using glucose as reducing reagent and silver-ammonia solution as precurso. The microstructures and phase composition of glass frits coated silver were characterized by SEM, EDS and XRD. The effects of ethylene glycol activating and concentration of AgNO3 on silver coating were studied when pH of the solution is 13.0. The results show that, nano-silver coating is uniform when the concentration of silver nitrate and glucose are 0.057 mol/L and 0.088 mol/L. The polycrystalline silicon solar cells were prepared using ordinarily and modified glass frits, respectively. Compared with silver slurry made up by ordinarily glass frits, the face side silver slurry made up by modified glass frits can densified electrode grids and the translational ratio of sunlight to electricity increases from 17.45%to 17.51%.%采用乙二醇还原硝酸银工艺对玻璃粉进行活化处理,再以银氨溶液为前驱体、葡萄糖为还原剂,用化学镀法在玻璃粉表面镀覆纳米银层,得到 Ag/玻璃复合粉末。利用 X 射线衍射、扫描电镜及能谱分析等方法研究Ag/玻璃复合粉末的结构与成分,并在溶液 pH 值约为13.0的条件下,分别研究乙二醇活化与镀液中的硝酸银浓度c(AgNO3)对银镀层的影响。结果表明,在活化基础上,当c(AgNO3)为0.057 mol/L,葡萄糖浓度为0.088 mol/L时,得到均匀的纳米银镀层。分别采用普通玻璃粉与改性玻璃粉配制正面银浆,进一步制备多晶硅太阳能电池片,与普通玻璃粉相比,用镀银玻璃粉配制的正面银浆可以致密栅线,电池的光电转换效率从17.45%提高到17.51%。

  15. Electroless synthesis of cellulose-metal aerogel composites

    Science.gov (United States)

    Schestakow, M.; Muench, F.; Reimuth, C.; Ratke, L.; Ensinger, W.

    2016-05-01

    An environmentally benign electroless plating procedure enables a dense coating of silver nanoparticles onto complex cellulose aerogel structures. In the course of the nanoparticle deposition, the morphological characteristics of the aerogel are preserved, such as the continuous self-supporting network structure. While achieving a high metal loading, the large specific surface area as well as the low density is retained in the cellulose-metal aerogel composite. Due to the interesting features of cellulose aerogel substrates (e.g., the accessibility of its open-porous network) and electroless plating (e.g., the possibility to control the density, size, and composition of the deposited metal nanoparticles), the outlined synthetic scheme provides a facile and flexible route towards advanced materials in heterogeneous catalysis, plasmonics, and sensing.

  16. Study of pretreatment techniques and characterization of electroless silver on cenospheres

    Science.gov (United States)

    Cao, Xiao Guo; Zhang, Hai Yan

    2012-10-01

    Electroless Ag-coating of cenosphere particles is demonstrated in the present investigation. The electroless Ag-coating process is modified by replacing the conventional pretreatment and sensitization steps by only using a surface hydroxylation step with NaOH hydroxylating agent to simplify the steps and reduce the overall cost of the coating process. Furthermore, the activation and electroless plating steps are merged into one step. The cenosphere particles are characterized by scanning electron microscope (SEM), energy dispersive x-ray spectroscopy (EDX), X-ray diffraction analysis (XRD), and fourier transform infrared (FT-IR) before and after the coating process. The relatively uniform and continuous coating is obtained under the given coating conditions. The possible mechanism of electroless Ag-coating of cenosphere particles utilizing surface hydroxylation of cenospheres is suggested.

  17. Study of the Electroless Deposition of Ni for Betavoltaic Battery Using PN Junction without Seed Layer

    Directory of Open Access Journals (Sweden)

    Jin Joo Kim

    2015-01-01

    Full Text Available The method and conditions of Ni plating were optimized to maximize the output of a betavoltaic battery using radioactive 63Ni. The difference of the short circuit currents between the pre- and postdeposition of 63Ni on the PN junction was 90 nA at the I-V characteristics. It is suspected that the beta rays emitted from 63Ni did not deeply penetrate into the PN junction due to a Ni seed layer with a thickness of 500 Å. To increase the penetration of the beta rays, electroless Ni plating was carried out on the PN junction without a seed layer. To establish the electroless coating conditions for 63Ni, nonradioactive Ni was deposited onto a Si wafer without flaws on the surface. This process can be applied for electroless Ni plating on a PN junction semiconductor using radioactive 63Ni in further studies.

  18. PLATE

    DEFF Research Database (Denmark)

    Kling, Joyce; Hjulmand, Lise-Lotte

    2008-01-01

    Project in Language Assessment for Teaching in English (PLATE) language professionals from CBS’s Language Center observe teachers and provide feedback using evaluation criteria from the Common European Framework for Reference (CEFR) supplemented by some additional criteria which take the LSP nature of......Copenhagen Business School (CBS) finds itself needing to address the issue of English-medium instruction for its increasing number of foreign exchange and full degree students. With internationalisation as a main pillar of the institution’s agenda, there are concerns whether the teaching faculty......’s level of English is sufficient for the increasing number of courses offered in English each semester. This paper addresses these concerns and describes a pilot project initiated in 2003 at CBS to gauge the overall English language proficiency of those teaching content courses in English. Through the...

  19. Stress of electroless copper deposits on insulating and metal substrates

    Energy Technology Data Exchange (ETDEWEB)

    Brüning, Ralf, E-mail: rbruening@mta.ca [Physics Department, Mount Allison University, Sackville, New Brunswick E4L 1E6 (Canada); Sibley, Allison; Sharma, Tanu; Brown, Delilah A.; Demay, Thibault [Physics Department, Mount Allison University, Sackville, New Brunswick E4L 1E6 (Canada); Brüning, Frank; Bernhard, Tobias [Atotech Deutschland GmbH, Erasmusstrasse 20, 10553 Berlin (Germany)

    2014-08-28

    In the fabrication of printed circuit boards, electroless copper is plated on insulating substrates. However, data for film stress by substrate bending are frequently obtained with metal substrates. We compare the stress evolution on an insulating substrate (acrylonitrile butadiene styrene) with results from commercial Ni–Fe and Cu–Fe alloy test strips, as well as X-ray diffraction based strain data. Tests were done with two plating bath formulations, one with and one without added nickel. Substrate type and condition determine the stress near the beginning of plating. Stress of the Ni-free films depends more strongly on the substrate material. Further, when the samples are cooled from the bath operating temperature to room temperature, the thermal contraction of the insulating substrate compresses the plated thin copper film. The measured stress change agrees with the change predicted by calculation. Data correction methods are discussed, and other substrate materials can be tested readily with the method employed here. - Highlights: • We report stress of electroless Cu deposits on insulating and metal substrates. • The final deposit stress is substrate-independent. • The final deposit stress and the X-ray diffraction based strain agree. • The stress change due to the thermal contraction of the substrate is observed. • Plating bath type, substrate and surface preparation alter the stress.

  20. Electroless Ag coating of fly ash cenospheres using polyaniline activator

    International Nuclear Information System (INIS)

    The electroless Ag coating of fly ash cenospheres employing polyaniline activator was investigated after polyaniline activator was coated on the surfaces of the cenosphere particles by in situ chemical polymerization. The composites were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, UV-visible absorption spectroscopy, x-ray diffraction and thermogravimetric analysis (TGA). The results indicate that a small amount of polyaniline activator was deposited in a discontinuous way on the surfaces of the cenosphere particles. Due to the activation of polyaniline, relatively compact and continuous Ag layer with a thickness of about 4 μm was obtained under the given electroless plating condition. The possible interaction between polyaniline and silver ions and the mechanism of Ag deposition were also investigated by the x-ray photoelectron spectroscopy technique.

  1. Electroless Ag coating of fly ash cenospheres using polyaniline activator

    Energy Technology Data Exchange (ETDEWEB)

    Wang Wei; Li Qin; Li Ying; Xu Hui; Zhai Jianping, E-mail: jpzhai@nju.edu.c [State Key Laboratory of Pollution Control and Resource Reuse, and School of the Environment, Nanjing University, Nanjing 210093 (China)

    2009-11-07

    The electroless Ag coating of fly ash cenospheres employing polyaniline activator was investigated after polyaniline activator was coated on the surfaces of the cenosphere particles by in situ chemical polymerization. The composites were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, UV-visible absorption spectroscopy, x-ray diffraction and thermogravimetric analysis (TGA). The results indicate that a small amount of polyaniline activator was deposited in a discontinuous way on the surfaces of the cenosphere particles. Due to the activation of polyaniline, relatively compact and continuous Ag layer with a thickness of about 4 {mu}m was obtained under the given electroless plating condition. The possible interaction between polyaniline and silver ions and the mechanism of Ag deposition were also investigated by the x-ray photoelectron spectroscopy technique.

  2. Electroless Ag coating of fly ash cenospheres using polyaniline activator

    Science.gov (United States)

    Wang, Wei; Li, Qin; Li, Ying; Xu, Hui; Zhai, Jianping

    2009-11-01

    The electroless Ag coating of fly ash cenospheres employing polyaniline activator was investigated after polyaniline activator was coated on the surfaces of the cenosphere particles by in situ chemical polymerization. The composites were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, UV-visible absorption spectroscopy, x-ray diffraction and thermogravimetric analysis (TGA). The results indicate that a small amount of polyaniline activator was deposited in a discontinuous way on the surfaces of the cenosphere particles. Due to the activation of polyaniline, relatively compact and continuous Ag layer with a thickness of about 4 µm was obtained under the given electroless plating condition. The possible interaction between polyaniline and silver ions and the mechanism of Ag deposition were also investigated by the x-ray photoelectron spectroscopy technique.

  3. A New Activation Method for Electroless Metal Plating:Palladium Laden via Bonding with Self—Assembly Monolayers

    Institute of Scientific and Technical Information of China (English)

    LiNaXU; JianHuiLIAO; 等

    2002-01-01

    A new activation method has been developed for electroless copper plating on silicon wafer based on palladium chemisorption on SAMs of APTS without SnCl2 sensitization and roughening condition.A closely packed electroless copper film with strong adhesion is successfully formed by AFM observation.XPS study indicates that palladium chemisorption occurred via palladium chloride bonding to the pendant amino group of the SAMs.

  4. Atomic force microscopy and x-ray photoelectron spectroscopy investigations of the morphology and chemistry of a PdCl2/SnCl2 electroless plating catalysis system adsorbed onto shape memory alloy particles

    Science.gov (United States)

    Silvain, J. F.; Fouassier, O.; Lescaux, S.

    2004-11-01

    A study of the different stages of the electroless deposition of copper on micronic NiTi shape memory alloy particles activated by one-step and two-step methods has been conducted from both a chemical and a morphological point of view. The combination of x-ray photoelectron spectroscopy (XPS) measurements and atomic force microscopy (AFM) imaging has allowed detection of the distribution of the formed compounds and depth quantification and estimation of the surface topographic parameters. For the two-step method, at the sensitization of the early stages, it is observed by AFM that Sn is absorbed in form of clusters that tend to completely cover the surface and form a continuous film. XPS analysis have shown that Sn and Pd are first absorbed in form of oxide (SnO2 and PdO) and hydroxide [Sn(OH)4]. After the entire sensitization step, the NiTi substrate is covered with Sn-based compounds. After the sensitization and the activation steps the powder roughness increases. Behavior of the Sn and Pd growth for the one-step method does not follow the behavior found for the two-step method. Indeed, XPS analysis shows a three-dimensional (3D) growth of Pd clusters on top of a mixture of metallic tin, oxide (SnO) and hydroxide [Sn(OH)2]. These Pd clusters are covered with a thin layer of Pd-oxide contamination induced by the electroless process. The mean roughness for the one-step and two-step processes are equivalent. After copper deposition, the decrease of mean roughness is attributed to a filling of surface valleys, observed after the Sn-Pd coating step.

  5. Atomic force microscopy and x-ray photoelectron spectroscopy investigations of the morphology and chemistry of a PdCl2/SnCl2 electroless plating catalysis system adsorbed onto shape memory alloy particles

    International Nuclear Information System (INIS)

    A study of the different stages of the electroless deposition of copper on micronic NiTi shape memory alloy particles activated by one-step and two-step methods has been conducted from both a chemical and a morphological point of view. The combination of x-ray photoelectron spectroscopy (XPS) measurements and atomic force microscopy (AFM) imaging has allowed detection of the distribution of the formed compounds and depth quantification and estimation of the surface topographic parameters. For the two-step method, at the sensitization of the early stages, it is observed by AFM that Sn is absorbed in form of clusters that tend to completely cover the surface and form a continuous film. XPS analysis have shown that Sn and Pd are first absorbed in form of oxide (SnO2 and PdO) and hydroxide [Sn(OH)4]. After the entire sensitization step, the NiTi substrate is covered with Sn-based compounds. After the sensitization and the activation steps the powder roughness increases. Behavior of the Sn and Pd growth for the one-step method does not follow the behavior found for the two-step method. Indeed, XPS analysis shows a three-dimensional (3D) growth of Pd clusters on top of a mixture of metallic tin, oxide (SnO) and hydroxide [Sn(OH)2]. These Pd clusters are covered with a thin layer of Pd-oxide contamination induced by the electroless process. The mean roughness for the one-step and two-step processes are equivalent. After copper deposition, the decrease of mean roughness is attributed to a filling of surface valleys, observed after the Sn-Pd coating step

  6. Kinetics of electroless Ni-Cu-P deposits on silicon in a basic hypophosphite-type bath

    Institute of Scientific and Technical Information of China (English)

    Wei-Long Liu; Shu-Huei Hsieh; Wen-Jauh Chen

    2009-01-01

    Eleetroless Ni-Cu-P deposits were deposited on the Si substrate in a basic hypophosphite-type plating bath.The effects ofpH value and the metal source composition, Ni and Cu, in the plating bath on the kinetics of the Ni-Cu-P deposition were studied.The electroless Ni-Cu-P deposits were characterized by a scanning electron microscope, a transmission electron microscope, an en-ergy dispersive X-ray spectroscope, and an X-ray diffractometer.The results showed that the pH value of the plating bath had no ob- vious effect on the morphology and composition of electroless Ni-Cu-P deposits.However, the composition of the metal source, Ni and Cu, in the plating bath had great effect on the kinetics of electroless Ni-Cu-P deposition.

  7. Electroless copper deposition as a seed layer on TiSiN barrier

    International Nuclear Information System (INIS)

    Electroless deposition of copper as a seeding technology has received considerable attention in back-end-of-line device fabrication. This work explores the effects of plasma processing parameters such as argon gas flow rate and nitrogen plasma treatment time on the properties of electrolessly plated Cu on TiSiN barrier layers. The barrier film was produced by a low-frequency inductively coupled plasma process. The properties of deposited electroless copper are characterized by x-ray diffraction, four-point resistivity probe, atomic force microscopy, and field emission scanning electron microscope. The required palladium activation time is greatly reduced on TiSiN compared to TiN. In both cases there exists a preferred (111) crystal orientation in Cu film and the intensity ratio of I(111)/I(200) is very close. The Cu grain size is within the range of 23-34 nm for 84 nm thick film. It is found that argon gas flow rate does not have a significant effect on the resistivity of electroless copper film on TiSiN. However, increasing nitrogen plasma treatment time reduces the resistivity of copper film. The roughness of plated Cu layer largely follows the one of the underlying TiSiN. Good surface coverage of electroless Cu seed layer on TiSiN has been achieved in our experiment

  8. Study of electroless Ni-W-P alloy coating on martensitic stainless steel

    Science.gov (United States)

    Nikitasari, Arini; Mabruri, Efendi

    2016-04-01

    Electroless nickel phospor (Ni-P) is widely used in many industries due to their corrosion and wear resistance, coating uniformity, and ability to coat non-conductive surfaces. The unique properties of tungsten such as high hardness, higher melting point, lower coefficient of linear thermal expansion, and high tensile strength have created a lot of interest in developing ternary Ni-W-P alloys. This article presents the study of electroless Ni-W-P alloys coating using acid or alkaline bath on martensitic stainless steel. Nickel sulfate and sodium tungstate were used as nickel and tungsten sources, respectively, and sodium hypophosphite was used as a reducing agent. Acid or alkaline bath refer to bath pH condition was adjusted by adding sulfuric acid. Martensitic stainless steel was immersed in Ni-W-P bath for 15, 30, and 60 minutes. The substrate of martensitic stainless steel was subjected to pre-treatment (polishing and cleaning) and activation prior to electroless plating. The plating characteristics were investigated for concentration ratio of nickel and hypophosphite (1:3), sodium tungstate concentration 0,1 M, immersion time (15 min, 30 min, 60 min), and bath condition (acid, alkaline). The electroless Ni-W-P plating was heat treated at 400°C for 1 hour. Deposits were characterized using scanning electron microscope (SEM) and corrosion measurement system (CMS).

  9. A Precious Metal-Free Electroless Technique for the Deposition of Copper on Carbon Fibers

    Science.gov (United States)

    Che, Dehui; Yao, Guangchun; Cao, Zhuokun

    2012-11-01

    This article introduces a new technique of electroless copper deposition on carbon fibers in the absence of precious metal as the catalyst. Copper layers were electrolessly deposited on the surface of carbon fiber without using the conventional palladium or silver catalyst to initiate redox reactions leading to metallization. This new technique shows that nickel seeds can serve as excellent catalysts to expedite the redox reactions. By performing experiments, parameters such as activation temperature, nickel ion concentration, and pH value were optimized, and an orbicular copper plating layer of carbon fiber was obtained in the copper sulfate salt-based conventional electroless solution. The surface morphology of copper coating was characterized by scanning electron microscopy and X-ray diffraction. The results indicate that uniform and smooth copper coating could be obtained by the new precious-metal free activation process. The resulting copper coating thickness is about 1 μm.

  10. TEMPERATURE DEPENDENCE OF ELECTROLESS Ni–P DEPOSITION ON POLYESTER FABRIC

    OpenAIRE

    R. H. GUO; Jiang, S Q; C. W. M. Yuen; M. C. F. NG

    2008-01-01

    The effects of plating temperature on the plating rate, P content, surface morphology, and electrical resistance of the electroless Ni–P deposits were studied. The results showed that the deposition rate of the Ni–P deposit and P content of the Ni–P layer increased with the rise of temperature of the plating bath. Scanning electron microscopy of the Ni–P deposits showed a nodule structure. The Ni–P plating layers had an amorphous structure and surface resistance of the layer decreased with th...

  11. The Effect of pH on the Electroless Ni Plating on the SiC Powder%pH值对碳化硅粉体表面镀镍的影响

    Institute of Scientific and Technical Information of China (English)

    姚怀; 朱广林

    2013-01-01

    The surface of SiC was plating mental of Ni, and the effect of pH of plating bath on plating speed, phase composition and microstructure was investigated. The results show that the SiC powders have no plating mental of Ni and no reaction can occur when the pH below 8.5. When the pH value is between 10 and 11, the weight gain of powders close to the theoretical value, the Ni peaks in X-ray diffraction patterns of powders is relatively strong and the substrate is covered of Ni plating completely. When the pH value is above 11, the gas production is becoming more pronounced and the reaction speed accelerates significantly with the increased of the pH value, the time of the plating bath changed from dark blue to colorless is obviously shortened. The double-plating is be carry out when the pH value is between 10 and 11, the plating becomes more thickness and has a uneven surfaces, the sizes of Ni particle are not uniform.%对碳化硅表面进行化学镀镍,研究了镀液的pH值对镀速、镀层组织及形貌的影响.结果表明:镀液pH值低于8.5时,无反应发生,粉体未镀上镍;pH值为10 ~11时,粉体的增重接近理论值,XRD图谱中的镍衍射峰较强,镀层完全覆盖基体;pH值高于11时,随着pH值的升高,气体生成越发明显,反应速度明显加快,镀液由深蓝色变为无色的时间明显缩短.在pH值10~11范围内对粉体进行二次化学镀,镀层厚度明显增大且显得凸凹不平,镀层中的镍颗粒大小不均匀.

  12. Electroless Ni-P Deposition on Magnesium Alloy from a Sulfate Bath

    Institute of Scientific and Technical Information of China (English)

    LI Guangyu; NIU Liyuan; JIANG Qing; JIANG Zhonghao; LIAN Jianshe

    2008-01-01

    A technology for electroless Ni-P deposition on AZ91D from a low cost plating bath containing sulfate nickel was proposed.The seal pretreatment was employed before the electroless Ni-P deposition for the sake of occluding the micro holes of the cast magnesium alloy and interdicting the bubble formation in the Ni-P coating during plating process.And pickling pretreatment can provide a better adhesion between the Ni-P deposition and AZ91D substrate.The deposition speed of the Ni-P coating is 29 um/h.The technology is employed to AZ91D magnesium alloy automobile parts and can provide high hardness and high wear-resistant.The weight losses of Ni-P plated and heat-treated Ni-P plated magnesium alloy specimen are only about I/6 and 1/10 that of bare magnesium alloy specimen after l0 min abrasion wear,respectively.The hardness of the electroless Ni-P plated brake pedal support brackets is 674.1 VHN and 935.7 VHN after 2 hours heat treatments at 180 C.The adhesion of Ni-P coatings on magnesium alloy substrates meets the demands of ISO Standards 2819.The technology is environment friendly and cannot cause hazard to environment because of absence of chromate in the whole process.

  13. Ductile electroless Ni-P coating onto flexible printed circuit board

    Science.gov (United States)

    Wang, Wenchang; Zhang, Weiwei; Wang, Yurong; Mitsuzak, Naotoshi; Chen, Zhidong

    2016-03-01

    In this study, a ductile electroless Ni-P coating on the flexible printed circuit board (FPCB) was prepared in an acidic nickel plating bath. The addition of dipropylamine (DPA) in electroless plating not only improves the ductility of the Ni-P coating, but also enhances the corrosion resistance. The further analysis reveals that the ductility improvement and enhancement of corrosion resistance for the Ni-P coating may be due to the fact that the addition of DPA significantly refines the volume of columnar nodule and reduce the porosity, thus leading to the released internal stress. In addition, it was found that the nodule within the Ni-P coating grew into a columnar structure, which may be also contribute to the improvement of ductility.

  14. Novel technology of electroless Ni-W-P on plastics and its interface behavior

    Institute of Scientific and Technical Information of China (English)

    WANG Tian-xu; HU Yong-jun; MENG Ji-long

    2004-01-01

    The electroless Ni-W-P coatings on polyoxymethylene(POM) were prepared. The POM was pretreated by hot spraying Al powder on it. Before the electroless Ni-W-P deposition, the POM with Al coating was flash plated in alkaline bath. The mechanism of Ni-W-P deposition was studied and the technology was optimized. The XRD analysis shows that the "as-deposited" Ni-W-P plating has mixed crystalline structure. The hardness value of deposits is more than HV700. The abrasion resistance of deposits is six times more than that of POM. Bending test was used to determine the cohesion between the deposits and the substrates. SEM was used to study the behavior of surface abrasion and interface bonding condition. The reason for the excellent cohesion was interpreted.

  15. Metal patterning on silicon surface by site-selective electroless deposition through colloidal crystal templating.

    Science.gov (United States)

    Asoh, Hidetaka; Sakamoto, Seiji; Ono, Sachiko

    2007-12-15

    Site-selective Cu deposition on a Si substrate was achieved by a combination of colloidal crystal templating, hydrophobic treatment, and electroless plating. Uniformly sized nano/microstructures were produced on the substrate using a monolayer coating of colloidal spheres instead of a conventional resist. The Cu patterns obtained were of two different types: networklike honeycomb and isolated-island patterns with a minimum period of 200 nm. Each ordered pattern with the desired intervals was composed of clusters of Cu nanoparticles with a size range of 50-100 nm. By the present method, it is possible to control the periodicity of metal arrays by changing the diameter of the colloidal spheres used as an initial mask and to adjust the shape of the metal patterns by changing the mask structure for electroless plating. PMID:17915242

  16. Electroless fabrication and supercapacitor performance of CNT@NiO-nanosheet composite nanotubes

    Science.gov (United States)

    Yu, W.; Li, B. Q.; Ding, S. J.

    2016-02-01

    Composite nanostructures consisting of porous NiO nanosheets on carbon nanotubes (CNTs) are fabricated using a facile and low-cost electroless plating method. The CNTs, modified by a polymer, are adopted as the template upon which porous Ni nanosheets are grown using electroless plating. This is followed by removal of the polymer layer and oxidation of the Ni by controlled thermal annealing. The effect of reductant concentration on the morphology of the NiO nanosheets is studied. The electrochemical characteristics of the nanostructures are measured using chronopotentiometry. Experimental measurements show that the NiO nanosheet covered CNT composite nanostructures exhibit a relatively high specific capacitance of 1177 F g-1 at a discharge current density of 2 A g-1, while retaining 89.2% of its initial capacitance at a current density of 2 A g-1 after 1000 cycles.

  17. Investigation into conductivity of silver-coated cenosphere composites prepared by a modified electroless process

    Science.gov (United States)

    Cao, Xiao Guo; Zhang, Hai Yan

    2013-01-01

    Silver-coated cenosphere composites are successfully fabricated by a modified electroless plating process that is modified by replacing the conventional pretreatment and sensitization steps by only using surface hydroxylation step to simplify the steps and reduce the overall cost of the coating process. Furthermore, the activation and electroless plating steps are merged into one step. The cenosphere particles are characterized by scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction analysis (XRD) before and after the coating process. The relatively continuous and compact coating is obtained under the given coating conditions. The results indicated that the conductivity of Ag-coated cenospheres was improved with increasing the AgNO3 solution dosage and reaction time. It was also found that the optimum AgNO3 solution concentration was 0.05 mol/L, and the optimum range of reaction temperature was from 50 °C to 65 °C.

  18. Effects of Two Purification Pretreatments on Electroless Copper Coating over Single-Walled Carbon Nanotubes

    OpenAIRE

    Zhong Zheng; Lianjie Li; Shijie Dong; Anchun Xiao; Shixuan Sun; Sinian Li

    2014-01-01

    To achieve the reinforcement of copper matrix composite by single-walled carbon nanotubes, a three-step-refluxing purification of carbon nanotubes sample with HNO3-NaOH-HCl was proposed and demonstrated. A previously reported purification process using an electromagnetic stirring with H2O2/HCl mixture was also repeated. Then, the purified carbon nanotubes were coated with copper by the same electroless plating process. At the end, the effects of the method on carbon nanotubes themselves and o...

  19. Métallisation Electroless des Polymères Induite par des Ligands

    OpenAIRE

    Garcia, Alexandre

    2011-01-01

    The main goal of this research project was to answer to an industrial issue: To develop a "green" process for the electroless plating of polymers without chromic acid (CrVI) etching. During this work, an alternative process based on an innovative surface coating technology (Graftfast® technology) has been developed. This technique which is working in aqueous solution and at room temperature allows to chemically graft vinylic polymers on various types of substrates. Based on this method, a pol...

  20. Towards an electroless deposition of gold on metallic substrates using ionic liquids as electrolytes

    OpenAIRE

    Sá, A. I. Correia de; Quaresma, S.; Eugénio, S.; Rangel, C. M.; Vilar, Rui

    2010-01-01

    Recent research has suggested a number of applications for gold in fuel cells and related hydrogen fuel processing, which include coatings for light weight corrosion resistance bipolar plates and the incorporation of gold as catalyst to provide improvements in electrode conductivity, among others. This paper reports on the electroless deposition of gold on copper substrates from a HAuCl4.3H2O solution in 1-butyl-1-methylpyrrolidinium dicyanamide (BMP-DCA), in normal atmospheric conditions. Th...

  1. Preparation and in-vitro Antibacterial Evaluation of Electroless Silver Coated Polymers

    OpenAIRE

    Fazeli, Mohammad Reza; Hosseini, Vahid; Shamsa, Fazel; Jamalifar, Hossein

    2010-01-01

    Long-term use of indwelling medical catheters has often been hindered by catheter-associated nosocomial infections. In this study the effectiveness of silver coating of polystyrene and polyethylene polymers was investigated. Polymer pieces of 2 cm2 each were coated with a thin layer of silver using electroless plating technique. Silver-coated polymers were challenged with cultures of four different microorganisms known for their involvement in nosocomial infections in both solid and broth med...

  2. Direct Ni Electroless Metallization of Poly(etherimide) without Using Palladium as a Catalyst

    Institute of Scientific and Technical Information of China (English)

    Mariène Charbonnier; Maurice Romand; Yves Goepfert

    2004-01-01

    Nickel or copper electroless metallization of polymers needs the grafting of a catalyst (palladium in the Pd(0) oxidation state) on the substrate surface to be coated. Our previous works on this topic [1-5] have allowed to develop a simple, tin-free method to attach Pd(+2) species from a palladium chloride (PdCl2) solution on any insulating surface and subsequently to reduce them, in the wet way, into the Pd(0) oxidation state. This Pd(0) state of the catalyst allows an instantaneous initiation of the Ni or Cu deposit by immersion in a plating bath. As palladium is an expensive chemical, it appears interesting to replace it by Ni(0) or Cu(0) species which are catalysts of their own ion reduction. Concerning the direct Ni electroless plating, the polymer surface (PI) was made catalytic for the electroless process by deposition (spincoating or dipping) of an ultra-thin film of an organic nickel salt in an alcoholic solution. The chemical reduction of this salt, checked by XPS, was performed by chemical or photochemical ways and by plasma. Under these conditions, the initiation, by autocatalysis, of the Ni film deposition in an industrial plating bath was immediate i.e. without any initiation time. The film obtained was homogeneous, dense, bright, well-adhering up to thicknesses reaching 3 μm.

  3. Adhesion enhancement between electroless nickel and polyester fabric by a palladium-free process

    Energy Technology Data Exchange (ETDEWEB)

    Lu Yinxiang, E-mail: yxlu@fudan.edu.cn [Department of Materials Science, Fudan University, 220 Handan Road, Shanghai 200433 (China); Xue Longlong; Li Feng [Department of Materials Science, Fudan University, 220 Handan Road, Shanghai 200433 (China)

    2011-01-15

    A new, efficient, palladium- and etchant-free process for the electroless nickel plating of poly(ethylene terephthalate) (PET) fabric has been developed. PET electroless plating can be prepared in three steps, namely: (i) the grafting of thiol group onto PET, (ii) the silver Ag{sup 0} seeding of the PET surface, and (iii) the nickel metallization using electroless plating bath. Scanning electron microscopy (SEM), energy dispersive X-ray (EDX) analysis, X-ray photoelectron spectroscopy (XPS), Raman spectrometer, X-ray diffraction (XRD), and thermogravimetric analysis (TG) were used to characterize the samples in the process, and the nickel loading was quantified by weighing. This process successfully compares with the traditional one based on KMnO{sub 4}/H{sub 2}SO{sub 4} etching and palladium-based seed layer. The nickel coating obtained in this palladium-free process can pass through ultrasonic washing challenge, and shows excellent adhesion with the PET substrate. However, the sample with Pd catalyst via traditional process was damaged during the testing experiment.

  4. Adhesion enhancement between electroless nickel and polyester fabric by a palladium-free process

    International Nuclear Information System (INIS)

    A new, efficient, palladium- and etchant-free process for the electroless nickel plating of poly(ethylene terephthalate) (PET) fabric has been developed. PET electroless plating can be prepared in three steps, namely: (i) the grafting of thiol group onto PET, (ii) the silver Ag0 seeding of the PET surface, and (iii) the nickel metallization using electroless plating bath. Scanning electron microscopy (SEM), energy dispersive X-ray (EDX) analysis, X-ray photoelectron spectroscopy (XPS), Raman spectrometer, X-ray diffraction (XRD), and thermogravimetric analysis (TG) were used to characterize the samples in the process, and the nickel loading was quantified by weighing. This process successfully compares with the traditional one based on KMnO4/H2SO4 etching and palladium-based seed layer. The nickel coating obtained in this palladium-free process can pass through ultrasonic washing challenge, and shows excellent adhesion with the PET substrate. However, the sample with Pd catalyst via traditional process was damaged during the testing experiment.

  5. Adhesion enhancement between electroless nickel and polyester fabric by a palladium-free process

    Science.gov (United States)

    Lu, Yinxiang; Xue, Longlong; Li, Feng

    2011-01-01

    A new, efficient, palladium- and etchant-free process for the electroless nickel plating of poly(ethylene terephthalate) (PET) fabric has been developed. PET electroless plating can be prepared in three steps, namely: (i) the grafting of thiol group onto PET, (ii) the silver Ag0 seeding of the PET surface, and (iii) the nickel metallization using electroless plating bath. Scanning electron microscopy (SEM), energy dispersive X-ray (EDX) analysis, X-ray photoelectron spectroscopy (XPS), Raman spectrometer, X-ray diffraction (XRD), and thermogravimetric analysis (TG) were used to characterize the samples in the process, and the nickel loading was quantified by weighing. This process successfully compares with the traditional one based on KMnO4/H2SO4 etching and palladium-based seed layer. The nickel coating obtained in this palladium-free process can pass through ultrasonic washing challenge, and shows excellent adhesion with the PET substrate. However, the sample with Pd catalyst via traditional process was damaged during the testing experiment.

  6. Direct Ni Electroless Metallization of Poly(etherimide) without Using Palladium as a Catalyst

    Institute of Scientific and Technical Information of China (English)

    MarleneCharbonnier; MauriceRomand; YvesGoepfert

    2004-01-01

    Nickel or copper electroless metallization of polymers needs the grafting of a catalyst (palladium in the Pd(0) oxidation state) on the substrate surface to be coated. Our previous works on this topic [1-5] have allowed to develop a simple, tin-free method to attach Pd(+2) species from a palladium chloride (PdCl2) solution on any insulating surface and subsequently to reduce them, in the wet way, into the Pd(0) oxidation state. This Pd(0) state of the catalyst allows an instantaneous initiation of the Ni or Cu deposit by immersion in a plating bath. As palladium is an expensive chemical, it appears interesting to replace it by Ni(0) or Cu(0) species which are catalysts of their own ion reduction. Concerning the direct Ni electroless plating, the polymer surface (PI) was made catalytic for the electroless process by deposition (spincoating or dipping) of an ultra-thin film of an organic nickel salt in an alcoholic solution. The chemical reduction of this salt, checked by XPS, was performed by chemical or photochemical ways and by plasma. Under these conditions, the initiation, by autocatalysis, of the Ni film deposition in an industrial plating bath was immediate i.e. without any initiation time. The film obtained was homogeneous, dense, bright, well-adhering up to thicknesses reaching 3μm.

  7. Evolution of microstructure and electrical conductivity of electroless copper deposits on a glass substrate

    Energy Technology Data Exchange (ETDEWEB)

    Cui, Xiaoyun; Hutt, David A., E-mail: D.A.Hutt@lboro.ac.uk; Conway, Paul P.

    2012-07-31

    This paper describes the evolution of the microstructure and conductivity of electroless copper deposition on a glass substrate for applications in electronics manufacture. The glass was activated using a (3-aminopropyl)trimethoxysilane pre-treatment followed by a Pd/Sn catalyst. Surface morphology of the deposited copper films was characterized using a dual beam focused ion beam field emission scanning electron microscope, and together with atomic force microscopy, showed clearly that the roughness and grain size tended to increase with the plating time. Film thickness measurements showed a high initial deposition rate, which slowed to a constant level as the thickness increased above 100 nm. This corresponded with the resistivity of the films which decreased rapidly as the thickness increased from 20 to 100 nm, but then remained largely stable at a level approximately twice that of bulk copper. - Highlights: Black-Right-Pointing-Pointer Morphology of electroless Cu on glass characterized as a function of plating time. Black-Right-Pointing-Pointer The deposition rate of electroless Cu varied with deposition time. Black-Right-Pointing-Pointer The roughness and grain size of the Cu deposits increased with the plating time. Black-Right-Pointing-Pointer The resistivity of Cu films was measured and related to changes in microstructure.

  8. Nanocrystalline Pd alloy films coated by electroless deposition.

    Science.gov (United States)

    Strukov, G V; Strukova, G K; Batov, I E; Sakharov, M K; Kudrenko, E A; Mazilkin, A A

    2011-10-01

    The structures of palladium and palladium alloys thin films deposited from organic electrolytes onto metallic substrates by electroless plating method have been investigated. The coatings are dense, pore-free 0.005-1 microm thick films with high adhesive strength to the substrate surface. EDX, XRD, SEM and TEM methods were used to determine the composition and structure of alloy coatings of the following binary systems: Pd-Au, Pd-Ag, Pd-Ni, Pd-Pb, and ternary system Pd-Au-Ni. The coatings of Pd-Au, Pd-Ag and Pd-Ni have a solid solution structure, whereas Pd-Pb is intermetallic compound. It has been found that the deposited films consist of nanocrystalline grains with sizes in the range of 11-35 nm. Scanning and transmission electron microscopy investigations reveal the existence of clusters formed by nanocrystalline grains. The origin for the formation of nanocrystalline structures of coating films is discussed. PMID:22400291

  9. A novel electroless silver depositing method for magnesium alloys

    Institute of Scientific and Technical Information of China (English)

    ZHAO Hui; CUI Jian-zhong

    2006-01-01

    Depositing silver on magnesium alloy by both electroless plating and organic coatings was studied. The organic coating was made by immersing samples in organosilicon heat-resisting varnish. In this method the organic coating acts as interlayer between the substrate and silver film. When the reaction starts, silver deposits directly on the interlayer. X-ray diffraction and SEM analysis were used to determine the composition and morphology of the interlayer and silver film. The potentiodynamic polarization curves for corrosion studies of coated magnesium alloys were performed in a corrosive environment of 3.5% NaCl(mass fraction) at neutral pH (6.9). The results indicate that compared with the substrate, the corrosion resistance of coated magnesium alloys increases greatly. Moreover, the method proposed in this work is environmentally friendly, non-toxic chemicals were used. In addition, it provides a new concept for the corrosion inhibition of magnesium alloys.

  10. The New Plating Process on Plastics

    Institute of Scientific and Technical Information of China (English)

    Makoto Imamura; Jun Okada; Kazuya Satoh

    2004-01-01

    This process does not use general electroless plating solution containing formaldehyde(carcinogen) and phosphate(the object of waste water regulation). Furthermore, we succeeded in developing a new electroless copper plating solution which is usable semi-permanently by using the special reducing agent. The electroless deposition forms a very thin conductive film on substrate. Therefore, it can prevent some appearance defects (e.g. pits, pin-holes, laminations and inclusions) that occur in the conventional ones. In addition, it is possible to eliminate electroplating of copper from the process by applying the exclusive nickel solution in electroplating. Therefore, the obtained metal parts can be recycled as high quality stainless steel. Given this copper electroplating-free process, 25μ m-thick nickel deposition at the stage of electroplating, at least, enables the metal layers to show properties as versatile as those of the conventional(its total thickness is 25μ m in the comparative conventional process).

  11. Effect of SiC size on Ni-P-SiC coatings prepared by magnetic stirring-electroless plating method%SiC粒度对磁力搅拌-化学沉积Ni-P-SiC镀层的影响

    Institute of Scientific and Technical Information of China (English)

    王勇; 马春华; 楚殿庆

    2013-01-01

    用磁力搅拌-化学沉积方法在45钢表面制备Ni-P-SiC镀层,研究镀液中SiC颗粒粒度对镀层表面形貌、显微硬度及耐磨性能的影响.结果表明:随着SiC颗粒的粒度逐渐减小,镀层的平整度和致密性增加,SiC颗粒团聚现象越来越不明显;当SiC粒度为0.2μm,Ni-P-SiC镀层表面均匀分散着微小的SiC颗粒,镀层平整、致密,平均显微硬度为853.4HV;当SiC粒度为1,2μm,最大硬度差分别为25.8HV和40.5HV.随着磨损时间的增加,含有SiC粒度0.2 μm的Ni-P-SiC镀层的磨损量缓慢增加,而SiC粒度为2,1μm的Ni-P-SiC镀层的磨损量急剧增加.%Ni-P-SiC coatings were prepared by magnetic stirring-electroless plating method on 45 steel. The effect of SiC size on surface morphology, microhardness and binding force was investigated. The results show that the flatness and density of Ni-P-SiC coatings increase with SiC particle size decreasing. When the particle size of SiC is 0.2 μm, tiny SiC particles are uniformly distributed on the surface of coatings, the coatings are smooth and dense, and the average microhardness is 853.4HV. When the SiC particle size is 1 u,m and 2 μm, the microhardness change is bigger at different location of Ni-P-SiC coating, and the maximum is 25.8HV and 40.5HV, respectively. During the friction and wear test process, the wear rate of Ni-P-SiC coating with SiC size of 0.2 μm increases slowly. While the coatings with SiC size of 2 μm and 1 μm, the wear rate increases very sharply.

  12. Study of the Electroless Deposition of Ni for Betavoltaic Battery Using PN Junction without Seed Layer

    OpenAIRE

    Jin Joo Kim; Young Rang Uhm; Byoung Gun Choi; Kwang Jae Son

    2015-01-01

    The method and conditions of Ni plating were optimized to maximize the output of a betavoltaic battery using radioactive 63Ni. The difference of the short circuit currents between the pre- and postdeposition of 63Ni on the PN junction was 90 nA at the I-V characteristics. It is suspected that the beta rays emitted from 63Ni did not deeply penetrate into the PN junction due to a Ni seed layer with a thickness of 500 Å. To increase the penetration of the beta rays, electroless Ni plating was ca...

  13. Fabrication of Ni-B alloy coated vapor-grown carbon nanofibers by electroless deposition

    OpenAIRE

    Arai, Susumu; Imoto, Yuzo; Suzuki, Yosuke; Endo, Morinobu

    2011-01-01

    Ni-B alloy coated vapor-grown carbon nanofibers (VGCNFs) were fabricated by electroless deposition and their microstructures were investigated. The effects of heat treatment on the coated VGCNFs were also studied. VGCNFs could be coated with a homogeneous Ni-B alloy film using a plating bath containing dimethylaminoborane (DMAB) as a reducing agent. The boron content of the Ni-B alloy film could be varied from 14 to 24 atom% B by varying the DMAB concentration of the plating bath. The VGCNFs ...

  14. EFFECT OF ANNEALING TEMPERATURE ON HARDNESS AND WEAR RESISTANCE OF ELECTROLESS Ni–B–Mo COATINGS

    OpenAIRE

    IHSAN GÖKHAN SERIN; ALI GÖKSENLI

    2015-01-01

    Formation of nickel–boron–molybdenum (Ni–B–Mo) coating on steel by electroless plating and evaluation of their morphology, hardness and tribological properties post heat treatment at different temperatures for 1 h is investigated. The 25 μm thick coating is uniform and adhesion between the substrate and coating is good. Ni–B–Mo coating was amorphous-like structure in their as-plated condition and by 400°C heat-treated coating, nickel fully crystallized and nickel borides and molybdenum carbid...

  15. Study on Electrochemical Characteristics of Electroless Co-Ni-B Alloy with Cerium

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The effects of rare earth element cerium on composition and electrochemical characteristics of electroless Co-Ni-B alloy were studied in this paper. The alloy component was analyzed using Inductively Coupled Plasma (ICP). The plating rate is was determined by electronic balance. The cathode polarization curves and cyclic voltammogram during the electroless deposition were tested by LK998Ⅱmodel electrochemical analytical system. The results show that rare earth element Ce can co-deposit with cobalt-based alloy, and with mass increase of Ce added in aqueous solution, the contents of Co, Ni, Ce in alloy increase and the content of B decreases. Ce can increase deposition rate of alloy in some range. The rare earth makes deposition potential move to positive direction and makes polarizability decrease.

  16. Preparation and Tribological Properties of Ni-P Electroless Composite Coating Containing Potassium Titanate Whisker

    Institute of Scientific and Technical Information of China (English)

    Yaxu JIN; Lin HUA

    2007-01-01

    Nickel-phosphorus (Ni-P) composite coatings containing potassium titanate (K2Ti6O13) whiskers (PTWs) were prepared by electroless plating. The surface morphology and component of coatings were investigated by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX), respectively before and after wear test. The tribological performance was evaluated using a pin-on-disk wear tester under dry conditions. It is found that the Ni-P-PTWs composite coatings exhibit higher wear resistance than Ni-P and Ni-P-SiC electroless coatings. The favorable effects of PTWs on the tribological properties of the composite coatings are attributed to the super-strong mechanical properties and the specific tunneling structures of PTWs. The PTWs greatly reinforce the structure of the Ni-P-based composite coatings and thereby greatly reduce the adhesive and plough wear of Ni-P-PTWs composite coatings.

  17. Electroless deposition of superconducting MgB2 films on various substrates

    International Nuclear Information System (INIS)

    The superconducting properties of magnesium diboride (MgB2) films prepared by electroless deposition on various substrates including silver, gold and silicon are reported. In this study, MgB2 films were fabricated on silver, gold, and silicon using an electroless plating technique, while controlling the redox potential to improve the deposition quality. The structure, morphology, and superconducting properties of the samples were investigated using X-ray diffraction, magnetometry, scanning electron microscopy, and Raman spectroscopy. X-ray diffraction and Raman spectroscopy confirmed that the films are polycrystalline MgB2 but also contain some impurity phases. All the MgB2 films show superconducting transitions near 39 K, the value for bulk MgB2, with the superconducting volume fraction ranging from approximately 1 to 2%. We find a strong dependence of film quality with the oxidation potential of the bath.

  18. Study on the nano-composite electroless coating of Ni-P/Ag

    Energy Technology Data Exchange (ETDEWEB)

    Ma Hongfang [Department of Materials, Shandong Jianzhu University, Jinan 250101 (China); Department of Materials, Shandong University, Jinan 250100 (China)], E-mail: mahongfangsd@yahoo.com.cn; Tian Fang [Department of Materials, Shandong University, Jinan 250100 (China); Li Dan; Guo Qiang [Department of Materials, Shandong Jianzhu University, Jinan 250101 (China)

    2009-04-17

    The nano-composite coating of Ni-P/Ag was obtained by adding silver nanoparticles to the Ni-P electroless plating solutions. The properties of the coating were tested by scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), differential scanning calorimeter (DSC), X-ray diffraction (XRD) and microsclerometer. Silver nanoparticles changed the properties of the composite coating. The Ni-P electroless coating contains 12.23 wt.% P while the composite coating of Ni-P/Ag contains 11.17 wt.% P and 0.24 wt.% Ag. The hardness of the composite coating is bigger than that of Ni-P alloy coating. Differential scanning calorimeter studies showed the amorphous to crystalline transition with precipitation of Ni{sub 3}P and Ni around 335 deg. C.

  19. Electroless deposition of superconducting MgB{sub 2} films on various substrates

    Energy Technology Data Exchange (ETDEWEB)

    Vijayaragavan, Khrupa S. [Department of Chemical Engineering and Materials Science, Wayne State University, Detroit, MI 48202 (United States); Putatunda, Susil K., E-mail: sputa@eng.wayn.ed [Department of Chemical Engineering and Materials Science, Wayne State University, Detroit, MI 48202 (United States); Dixit, Ambesh; Lawes, Gavin [Department of Physics and Astronomy, Wayne State University, Detroit, MI 48201 (United States)

    2010-11-01

    The superconducting properties of magnesium diboride (MgB{sub 2}) films prepared by electroless deposition on various substrates including silver, gold and silicon are reported. In this study, MgB{sub 2} films were fabricated on silver, gold, and silicon using an electroless plating technique, while controlling the redox potential to improve the deposition quality. The structure, morphology, and superconducting properties of the samples were investigated using X-ray diffraction, magnetometry, scanning electron microscopy, and Raman spectroscopy. X-ray diffraction and Raman spectroscopy confirmed that the films are polycrystalline MgB{sub 2} but also contain some impurity phases. All the MgB{sub 2} films show superconducting transitions near 39 K, the value for bulk MgB{sub 2}, with the superconducting volume fraction ranging from approximately 1 to 2%. We find a strong dependence of film quality with the oxidation potential of the bath.

  20. Study on the nano-composite electroless coating of Ni-P/Ag

    International Nuclear Information System (INIS)

    The nano-composite coating of Ni-P/Ag was obtained by adding silver nanoparticles to the Ni-P electroless plating solutions. The properties of the coating were tested by scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), differential scanning calorimeter (DSC), X-ray diffraction (XRD) and microsclerometer. Silver nanoparticles changed the properties of the composite coating. The Ni-P electroless coating contains 12.23 wt.% P while the composite coating of Ni-P/Ag contains 11.17 wt.% P and 0.24 wt.% Ag. The hardness of the composite coating is bigger than that of Ni-P alloy coating. Differential scanning calorimeter studies showed the amorphous to crystalline transition with precipitation of Ni3P and Ni around 335 deg. C

  1. Reactive coupling of 4-vinylaniline with hydrogen-terminated Si(100) surfaces for electroless metal and "synthetic metal" deposition.

    Science.gov (United States)

    Xu, D; Kang, E T; Neoh, K G; Tay, A A O

    2004-04-13

    Pristine and resist-patterned Si(100) substrates were etched by aqueous HF to produce hydrogen-terminated silicon (H-Si(100)) surfaces. The H-Si(100) surface was then subjected to UV-induced reactive coupling of 4-vinylaniline (VAn) to produce the VAn monolayer-modified silicon (VAn-Si) surface. The VAn-Si surface was first functionalized with a "synthetic metal" by oxidative graft polymerization of aniline with the aniline moieties of the coupled VAn molecules. The composition and topography of the VAn-Si and polyaniline (PAn)-grafted VAn-Si (PAn-VAn-Si) surfaces were characterized by X-ray photoelectron spectroscopy and atomic force microscopy, respectively. The doping-undoping (protonation-deprotonation) and redox-coupling (metal reduction) behavior, as well as the electrical conductivity, of the surface-grafted PAn were found to be similar to those of the aniline homopolymer. The VAn-Si surface was also funtionalized by the electroless plating of copper. Not only did the VAn layer provide chemisorption sites for the palladium catalyst, in the absence of prior sensitization by SnCl2, during the electroless plating process, it also served as an adhesion promotion layer and a low-temperature diffusion barrier for the electrolessly deposited copper. Finally, micropatterning of the grafted PAn and of the electrolessly deposited copper were demonstrated on the resist-patterned VAn-Si surfaces. PMID:15875865

  2. Experimental study on the formation and growth of electroless nickel-boron coatings from borohydride-reduced bath on mild steel

    Energy Technology Data Exchange (ETDEWEB)

    Vitry, Veronique, E-mail: veronique.vitry@umons.ac.be [Service de Metallurgie, Universite de Mons, Rue de l' Epargne 56, 7000 Mons (Belgium); Sens, Adeline [Service de Metallurgie, Universite de Mons, Rue de l' Epargne 56, 7000 Mons (Belgium); Kanta, Abdoul-Fatah [Service de Sciences des Materiaux, Universite de Mons, Rue de l' Epargne 56, 7000 Mons (Belgium); Delaunois, Fabienne [Service de Metallurgie, Universite de Mons, Rue de l' Epargne 56, 7000 Mons (Belgium)

    2012-12-15

    Highlights: Black-Right-Pointing-Pointer Initiation mechanism of electroless Ni-B on St-37 steel has been identified. Black-Right-Pointing-Pointer Different phases of the plating process were observed and identified. Black-Right-Pointing-Pointer Influence of chemical heterogeneity on coating morphology was revealed. Black-Right-Pointing-Pointer Batch replenishment of the plating bath induces new germination phase. - Abstract: Quality and homogeneity of electroless nickel-boron coatings are very important for applications in corrosion and electronics and are completely dependent on the formation of the deposit. The growth and formation process of electroless nickel-boron was investigated by immersing mild steel (St-37) samples in an un-replenished bath for various periods of time (from 5 s to 1 h). The coatings obtained at the different stages of the process were then characterized: thickness was measured by SEM, morphology was observed, weight gain was recorded and top composition of the coatings was obtained from XPS. Three main phases were identified during the coating formation and links between plating time, instantaneous deposition rate, chemistry of last formed deposit and morphology were established. The mechanism for initial deposition on steel substrate for borohydride-reduced electroless nickel bath was also observed. Those results were confronted with chemistry evolution in the unreplenished plating bath during the process. This allowed getting insight about phenomena occurring in the plating bath and their influence on coating formation.

  3. Electroless ternary NiCeP coatings: Preparation and characterisation

    International Nuclear Information System (INIS)

    Highlights: ► Rare earth element (Ce) has been successfully codeposited in NiP matrix. ► Surface analysis carried out by XPS showed that the Ce is present in +3 and +4 oxidation state. ► Palladium stability test indicated that the Ce salts in electroless nickel bath has reduced the stability. ► Cerium codeposition in NiP matrix has increased the microhardness both in as-plated and annealed conditions. ► Higher thermal stability has been obtained by Ce incorporation. - Abstract: Electroless ternary NiCeP deposits were prepared from alkaline citrate bath containing nickel sulphate, cerium chloride and sodium hypophosphite. Concentration of rare earth cerium was varied from 1 to 2 g/L to obtain ternary deposits containing variable Ce and P contents. The influence of cerium on the deposit properties was analysed. The deposit exhibited a maximum cerium content of 6.2 ± 0.1 wt.% when the cerium chloride concentration was 2 g/L. The result of the Pd stability test showed that the stability of the bath was reduced due to Ce salt addition. The microhardness measurements made on both as-plated and heat treated samples exhibited a peak hardness of 1006 ± 11 VHN for cerium concentration of 1.5 g/L. The concept of kinetic strength analysis was proved to be applicable only for binary and not for ternary alloys due to multistep deposition mechanism with different kinetic energies. X-ray diffraction (XRD) patterns of as-plated and heat treated samples revealed peaks corresponding to Ni (1 1 1) and nickel phosphide (Ni3P). Higher amount of Ce incorporation in NiP matrix increased the crystallisation temperature of the deposit which could be due to the suppression of nickel crystallisation prior to Ni3P compound formation and thus increasing the activation energy for the formation of stable phases. Surface compositional analysis using X-ray photoelectron spectroscopy (XPS) carried out on as-plated NiCeP-2 deposit showed a prominent peak of P existing in +1 oxidation

  4. Electroless ternary NiCeP coatings: Preparation and characterisation

    Energy Technology Data Exchange (ETDEWEB)

    Balaraju, J.N., E-mail: jnbalraj@nal.res.in [Surface Engineering Division, CSIR National Aerospace Laboratories, Post Bag No. 1779 Bangalore 560017, Karnataka (India); Chembath, Manju [Surface Engineering Division, CSIR National Aerospace Laboratories, Post Bag No. 1779 Bangalore 560017, Karnataka (India)

    2012-10-01

    Highlights: Black-Right-Pointing-Pointer Rare earth element (Ce) has been successfully codeposited in NiP matrix. Black-Right-Pointing-Pointer Surface analysis carried out by XPS showed that the Ce is present in +3 and +4 oxidation state. Black-Right-Pointing-Pointer Palladium stability test indicated that the Ce salts in electroless nickel bath has reduced the stability. Black-Right-Pointing-Pointer Cerium codeposition in NiP matrix has increased the microhardness both in as-plated and annealed conditions. Black-Right-Pointing-Pointer Higher thermal stability has been obtained by Ce incorporation. - Abstract: Electroless ternary NiCeP deposits were prepared from alkaline citrate bath containing nickel sulphate, cerium chloride and sodium hypophosphite. Concentration of rare earth cerium was varied from 1 to 2 g/L to obtain ternary deposits containing variable Ce and P contents. The influence of cerium on the deposit properties was analysed. The deposit exhibited a maximum cerium content of 6.2 {+-} 0.1 wt.% when the cerium chloride concentration was 2 g/L. The result of the Pd stability test showed that the stability of the bath was reduced due to Ce salt addition. The microhardness measurements made on both as-plated and heat treated samples exhibited a peak hardness of 1006 {+-} 11 VHN for cerium concentration of 1.5 g/L. The concept of kinetic strength analysis was proved to be applicable only for binary and not for ternary alloys due to multistep deposition mechanism with different kinetic energies. X-ray diffraction (XRD) patterns of as-plated and heat treated samples revealed peaks corresponding to Ni (1 1 1) and nickel phosphide (Ni{sub 3}P). Higher amount of Ce incorporation in NiP matrix increased the crystallisation temperature of the deposit which could be due to the suppression of nickel crystallisation prior to Ni{sub 3}P compound formation and thus increasing the activation energy for the formation of stable phases. Surface compositional analysis

  5. Laser Induced Selective Activation For Subsequent Autocatalytic Electroless Plating

    DEFF Research Database (Denmark)

    Zhang, Yang

    the activation colloids based on three hypotheses. The first hypothesis is that laser machining leads to chemical changes of the polymer, which results in chemical bonding with the activation colloids. Chemical changes on the laser track were investigated by XPS or FTIR spectroscopy, but no evidence shows....... can be directly used in the LISA process. Second, in the wet steps, no chromic acid or other similar toxic compounds are used. The principle of the PdCl2/SnCl2 activation system is explained based on previous researchers’ studies. Investigations were conducted as to how the laser tracks keep...... that chemical bonds exist. However, it is still not excluded that chemical bonding is part of the mechanism. The second hypothesis is that the laser track has a stronger attraction work to the activation solution. This is proved by a calculation using van Oss et al., theory based on contact angle measurement...

  6. SURFACE METALLIZATION OF CENOSPHERES AND PRECIPITATORS BY ELECTROLESS PLATING

    Institute of Scientific and Technical Information of China (English)

    Chujiang Cai; Zhigang Shen; Mingzhu Wang; Shulin Ma; Yushan Xing

    2003-01-01

    This paper reports the use of a colloidal Pd0 catalysis system to metallize the surface of precipitators separated from coal fly-ash, and metals such as Cu, Ni etc. are deposited on the precipitators surface. Alternatively,according to the characteristic surface of cenospheres, an Ag coating catalysis system is adopted to first deposit Ag on the cenospheres surface, followed, if necessary, by the deposition of other metals such as Cu, Ni, etc. on the Ag coating to produce monolayer and multilayer metal-coated cenospheres. The surface characteristics and the morphologies of the metal coatings are examined in detail with scanning electron microscopy (SEM), energy dispersive spectroscopy (EDX) and X-ray photoelectron spectroscopy (XPS) techniques. It can be shown that the quality of metal coatings derived from the Ag coating catalysis system, is better than that of the colloidal Pd0 catalysis system.

  7. Electroless deposition of metal nanoparticle clusters: Effect of pattern distance

    KAUST Repository

    Gentile, Francesco

    2014-04-03

    Electroless plating is a deposition technique in which metal ions are reduced as atoms on specific patterned sites of a silicon surface to form metal nanoparticles (NPs) aggregates with the desired characteristics. Those NPs, in turn, can be used as constituents of surface enhanced Raman spectroscopy substrates, which are devices where the electromagnetic field and effects thereof are giantly amplified. Here, the electroless formation of nanostructures was studied as a function of the geometry of the substrate. High resolution, electron beam lithography techniques were used to obtain nonperiodic arrays of circular patterns, in which the spacing of patterns was varied over a significant range. In depositing silver atoms in those circuits, the authors found that the characteristics of the aggregates vary with the pattern distance. When the patterns are in close proximity, the interference of different groups of adjacent aggregates cannot be disregarded and the overall growth is reduced. Differently from this, when the patterns are sufficiently distant, the formation of metal clusters of NPs is independent on the spacing of the patterns. For the particular subset of parameters used here, this critical correlation distance is about three times the pattern diameter. These findings were explained within the framework of a diffusion limited aggregation model, which is a simulation method that can decipher the formation of nanoaggregates at an atomic level. In the discussion, the authors showed how this concept can be used to fabricate ordered arrays of silver nanospheres, where the size of those spheres may be regulated on varying the pattern distance, for applications in biosensing and single molecule detection.

  8. Effect of 3-Amino-5-mercapto-1,2,4-triazole on Electroless Nickel Deposition

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The effects of organic additive, 3-amino-5-mercapto-1,2,4-triazole (AMTA) on bath stability, deposition rate,reaction activation energy, and Ni-P coating composition in acidic electroless nickel plating were investigated.Polarization curve method and infrared reflection spectroscopy were used to analyze the mechanism of the effect of AMTA on electroless nickel deposition. It was observed that AMTA improved bath stability, decreased the deposition rate, and increased the reaction activation energy. It was also revealed that AMTA decreased the phosphorus content and increased the sulfur content in Ni-P coating. In addition, AMTA inhibited the anodic oxidation of hypophosphite and accelerated the cathodic reduction of Ni2+. Infrared reflection spectroscopy result indicates that AMTA was adsorbed on the surface of Ni-P and interacted with Ni2+ to form an AMTA-Ni2+ compound. On the basis of the results of this study,the mechanism of the effect of AMTA on electroless nickel deposition was deduced.

  9. Comparative study of electroless nickel film on different organic acids modified cuprammonium fabric (CF)

    Science.gov (United States)

    Zhao, Hang; Lu, Yinxiang

    2016-01-01

    Nickel films were grown on citric acid (CA), malic acid (MA) and oxalic acid (OA) modified cuprammonium fabric (CF) substrates via electroless nickel deposition. The nickel films were examined using scanning electron microscopy (SEM) and X-ray diffraction (XRD). Their individual deposition rate and electromagnetic interference (EMI) shielding effectiveness (SE) were also investigated to compare the properties of electroless nickel films. SEM images illustrated that the nickel film on MA modified CF substrate was smooth and uniform, and the density of nickel nuclei was much higher. Compared with that of CA modified CF, the coverage of nickel nuclei on OA and MA modified CF substrate was very limited and the nickel particles size was too big. XRD analysis showed that the nickel films deposited on the different modified CF substrates had a structure with Ni (1 1 1) preferred orientation. All the nickel coatings via different acid modification were firmly adhered to the CF substrates, as demonstrated by an ultrasonic washing test. The result of tensile test indicated that the electroless nickel plating on CF has ability to strengthen the CF substrate while causes limited effect on tensile elongation. Moreover, the nickel film deposited on MA modified CF substrate showed more predominant in EMI SE than that deposited on CA or OA modified CF.

  10. Corrosion Resistance of Electroless Ni-Cu-P Ternary Alloy Coatings in Acidic and Neutral Corrosive Mediums

    OpenAIRE

    Mbouillé Cissé; Mohamed Abouchane; Tayeb Anik; Karima Himm; Rida Allah Belakhmima; Mohamed Ebn Touhami; Rachid Touir; Abderrahmane Amiar

    2010-01-01

    Electroless Ni-Cu-P alloy coatings were deposited on the ordinary steel substrate in an acidic hypophosphite-type plating bath. These coatings were characterized by a scanning electron microscope (SEM) and an X-ray diffraction. The micrograph shows that coating presents a nodular aspect and is relatively homogeneous and very smooth. The EDX analysis shows that the coating contains 12 wt.% of phosphorus element with a predominance of nickel element. In addition, the anticorrosion properties of...

  11. Selective Electroless Silver Deposition on Graphene Edges

    DEFF Research Database (Denmark)

    Durhuus, D.; Larsen, M. V.; Andryieuski, Andrei;

    2015-01-01

    We demonstrate a method of electroless selective silver deposition on graphene edges or between graphene islands without covering the surface of graphene. Modifications of the deposition recipe allow for decoration of graphene edges with silver nanoparticles or filling holes in damaged graphene...... on silica substrate and thus potentially restoring electric connectivity with minimal influence on the overall graphene electrical and optical properties. The presented technique could find applications in graphene based transparent conductors as well as selective edge functionalization and can be extended...

  12. Study of Ni-catalyst for electroless Ni-P deposition on glass fiber

    International Nuclear Information System (INIS)

    Highlights: → Electroless nickel-phosphorus plating on the glass fiber surface. → We study the pretreatment including roughening and activation process. → The pretreatment parameters are optimized by orthogonal experiments. → Nickel-catalyst method is developed to activate the glass fiber surface. → Activated film containing nickel oxide particles will form catalytic centers. - Abstract: The glass fiber surface is metalized with electroless nickel-phosphorus deposition. The roughening and activation processes are optimized by the orthogonal experiments. A new nickel-catalyst method is developed to activate the glass fiber surface. When the activation is completed, a layer of continuous and dense film is formed on the substrate. The activated film contains a great deal of nickel oxide particles which can become the active sites after they are deoxidized in the electroless bath. In the activated film on the glass fiber, the content of Ni element is 41.01 wt.%, the content of O element is 45.64 wt.% and the content of P element is 13.35 wt.%. Scanning electron microscopy (SEM) shows that the Ni-P coatings obtained under the optimum pretreatment conditions are uniform, continuous and adhered to the glass fiber surface. Energy dispersive X-ray spectrometry (EDS) points out that the content of the nickel and the phosphorus in the deposits is 87.41 wt.% and 12.59 wt.%, respectively. X-ray photoelectron spectroscopy (XPS) analysis reveals that the O signal on electroless Ni-coated glass surface corresponds to oxygen in the glass substrate. X-ray diffraction pattern (XRD) indicates the Ni-P coatings are amorphous.

  13. A plating method for metal coating of fiber Bragg grating

    Institute of Scientific and Technical Information of China (English)

    Yulong Li; Hua Zhang; Yan Feng; Gang Peng

    2009-01-01

    We present a method for metal coating optical fiber and in-fiber Bragg grating. The technology process which is based on electroless plating and electroplating method is described in detail. The fiber is firstly coated with a thin copper or nickel plate with electroless plating method. Then, a thicker nickel plate is coated on the surface of the conductive layer. Under the optimum conditions, the surfaces of chemical plating and electroplating coatings are all smooth and compact. There is no visible defect found in the cross-section. Using this two-step metallization method, the in-fiber Bragg grating can be well protected and its thermal sensitivity can be enhanced. After the metallization process, the fiber sensor is successfully embedded in the 42CrMo steel by brazing method. Thus a smart metal structure is achieved. The embedding results show that the plating method for metallization protection of in-fiber Bragg grating is effective.

  14. Electroless deposition of SnOx-Sb nanocoating in ordered titania pores for enhancing electrical conductivity

    International Nuclear Information System (INIS)

    Sn and Sb were separately deposited into TiO2 nanotubes (TNTs) by electroless plating. A more conductive sub-stoichiometric TNT/SnOx-Sb layer was then prepared by controlled annealing. The electrical properties of the TNT/SnOx-Sb electrodes were characterized by cyclic voltammetry and electrochemical impedance spectroscopy. The presence of Sn contributes to the enhanced electrical conductivity. A small amount of Sn greatly improves the energy efficiency of TNT/SnOx-Sb electrodes for the degradation of nitrobenzene by enhancing the conductivity.

  15. Electroless nickel-phosphorus coating on poly (ether ether ketone)/carbon nanotubes composite

    Science.gov (United States)

    Zhai, Tong; Di, Lizhi; Yang, De'an

    2014-05-01

    In order to improve electromagnetic shielding property of poly (ether ether ketone)/carbon nanotubes composite, a nickel-phosphorus coating was covered on the composite by electroless plating. The morphologies of the substrates and the coatings were characterized by SEM. XPS was performed to analyze the surface composition and chemical states before and after chemical etching. The results showed that lots of microscopic holes appeared and evenly distributed on the surface, and the concentration of hydrophilic groups on the surface increased after the composite was etched. Thermal shock test showed that the adhesive strength between the coating and the composite was good.

  16. Self-assembly monolayer of mercaptopropyltrimethoxysilane for electroless deposition of Ag

    International Nuclear Information System (INIS)

    Mercaptopropyltrimethoxysilane (MPTS) was used to form self-assembly monolayers (SAMs) on glass slides, which was verified by using X-ray photoelectron spectroscopy (XPS) and auger electron spectroscopy (AES). Electroless plating of Ag was performed on the SAMs-modified glass slide. XPS study showed that Ag colloids formed in solution were successfully and hard anchored on SAMs through chemical bonds. Scanning electron microscopy (SEM) analysis illustrated that Ag film on the SAMs-modified glass showed more predominant in durability of temperature than that on conventionally modified glass

  17. Surface modification of an epoxy resin with polyamines and polydopamine: Adhesion toward electroless deposited copper

    Science.gov (United States)

    Schaubroeck, David; Mader, Lothar; Dubruel, Peter; Vanfleteren, Jan

    2015-10-01

    In this paper the influence of the epoxy roughness, surface modifications and ELD (electroless copper deposition) temperatures on the adhesive strength of the copper is studied. Good adhesion at low roughness values is targeted due to their applicability in high density electronic circuits. Roughened epoxy surfaces are modified with adsorbed polyamines, polydopamine and polyamines grafted to polydopamine. Next the, adhesive strength of ELD copper is determined with peel strength measurements and the interphases are examined with SEM (scanning electron microscopy). Polydopamine and polyamines grafted to polydopamine can lead to increased adhesive strength at lower roughness values compared to the non-modified samples at specific plating temperatures.

  18. Investigation into conductivity of silver-coated cenosphere composites prepared by a modified electroless process

    Energy Technology Data Exchange (ETDEWEB)

    Cao Xiaoguo, E-mail: xgcao@gdut.edu.cn [School of Materials and Energy, Guangdong University of Technology, Guangzhou, Guangdong 510006 (China); Zhang Haiyan [School of Materials and Energy, Guangdong University of Technology, Guangzhou, Guangdong 510006 (China)

    2013-01-01

    Highlights: Black-Right-Pointing-Pointer In this paper we described a modified eletroless Ag-coating process on cenospheres. Black-Right-Pointing-Pointer The modified method makes the plating process more cost-saving and with less steps. Black-Right-Pointing-Pointer The relatively uniform and continuous silver coating is obtained. Black-Right-Pointing-Pointer The effects of silver coating on cenospheres on conductivity were investigated. - Abstract: Silver-coated cenosphere composites are successfully fabricated by a modified electroless plating process that is modified by replacing the conventional pretreatment and sensitization steps by only using surface hydroxylation step to simplify the steps and reduce the overall cost of the coating process. Furthermore, the activation and electroless plating steps are merged into one step. The cenosphere particles are characterized by scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction analysis (XRD) before and after the coating process. The relatively continuous and compact coating is obtained under the given coating conditions. The results indicated that the conductivity of Ag-coated cenospheres was improved with increasing the AgNO{sub 3} solution dosage and reaction time. It was also found that the optimum AgNO{sub 3} solution concentration was 0.05 mol/L, and the optimum range of reaction temperature was from 50 Degree-Sign C to 65 Degree-Sign C.

  19. Investigation into conductivity of silver-coated cenosphere composites prepared by a modified electroless process

    International Nuclear Information System (INIS)

    Highlights: ► In this paper we described a modified eletroless Ag-coating process on cenospheres. ► The modified method makes the plating process more cost-saving and with less steps. ► The relatively uniform and continuous silver coating is obtained. ► The effects of silver coating on cenospheres on conductivity were investigated. - Abstract: Silver-coated cenosphere composites are successfully fabricated by a modified electroless plating process that is modified by replacing the conventional pretreatment and sensitization steps by only using surface hydroxylation step to simplify the steps and reduce the overall cost of the coating process. Furthermore, the activation and electroless plating steps are merged into one step. The cenosphere particles are characterized by scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction analysis (XRD) before and after the coating process. The relatively continuous and compact coating is obtained under the given coating conditions. The results indicated that the conductivity of Ag-coated cenospheres was improved with increasing the AgNO3 solution dosage and reaction time. It was also found that the optimum AgNO3 solution concentration was 0.05 mol/L, and the optimum range of reaction temperature was from 50 °C to 65 °C.

  20. Development of electroless Ni-Zn-P/nano-TiO2 composite coatings and their properties

    International Nuclear Information System (INIS)

    Ni-Zn-P-TiO2 composite coatings were successfully obtained on low carbon steel by electroless plating technique. Deposits were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive analysis (EDS) studies. The hardness and microstructure of as plated and heat treated Ni-Zn-P and Ni-Zn-P-TiO2 composite coatings were analyzed. The change in microstructure and higher hardness was noticed for heat treated composite. The corrosion resistance behavior of as plated and heat treated Ni-Zn-P and Ni-Zn-P-TiO2 coatings was investigated by anodic polarization, Tafel plots and electrochemical impedance spectroscopic (EIS) studies in 3.5 wt% NaCl solution. The composite coating exhibited enhanced corrosion resistance property over Ni-Zn-P coating.

  1. Mechanical and electrochemical properties of ultrasonic-assisted electroless deposition of Ni–B–TiO2 composite coatings

    International Nuclear Information System (INIS)

    Highlights: • Ni–B–TiO2 coatings developed by ultrasonic-assisted electroless method. • Titania improves corrosion resistance and hardness of the Ni–B as-plated coatings. • Titania increases the surface film resistance of the Ni–B as-plated coatings. - Abstract: Nickel–Boron–Titania (Ni–B–TiO2) composite coatings were successfully obtained on mild steel (St-37) by simultaneous electroless deposition. TiO2 particles were dispersed in a suspension by ultrasonic irradiation. The surface morphology, particle size, elemental composition and phase analysis of the coatings were characterized by scanning electron microscopy (SEM), inductively coupled plasma (ICP) and X-ray diffraction (XRD). The hardness and friction coefficient of as- plated and heat treated Ni–B and Ni–B–TiO2 composite coatings were determined by Vickers diamond indentation and indentation scratch tests and compared with Ni–B coatings. As a result, the hardness (1263 HV) of the as-plated Ni–B–TiO2 coatings was improved significantly. In addition, the corrosion resistance behavior of the as-plated and heat treated Ni–B and Ni–B–TiO2 coatings were analyzed by anodic polarization and electrochemical impedance spectroscopic (EIS) studies in a 3.5 wt.% NaCl solution. The as-plated composite coatings (Ni–B–TiO2) exhibited enhanced corrosion resistance (0.2 μA/cm2) property over Ni–B coatings

  2. Highly adhesive metal plating on Zylon fiber via iodine pretreatment

    Energy Technology Data Exchange (ETDEWEB)

    Fatema, Ummul Khair [Faculty of Textile Science and Technology, Shinshu University, 3-15-1 Tokida, Ueda, Nagano 386-8567 (Japan); Gotoh, Yasuo, E-mail: ygotohy@shinshu-u.ac.jp [Faculty of Textile Science and Technology, Shinshu University, 3-15-1 Tokida, Ueda, Nagano 386-8567 (Japan)

    2011-11-01

    Highly adhesive metal plating was performed on poly(p-phenylene-2,6-benzobisoxazole) fiber named Zylon via iodine pretreatment followed by electroless plating. First, iodine components were selectively doped into the inner part of the fiber near the surface through iodine vapor exposure. The doped iodine was converted to palladium iodide particles by treating with palladium chloride solution. After the reduction of the iodide to metal palladium particles, electroless copper plating was conducted on the fiber. A uniform copper layer was deposited on the fiber surface and exhibited high durability in durability tests such as ultrasonic exposure, tape peeling-off, and corrosion in NaCl solution. This durability was attributed to the palladium particles formed at the fiber surface that served as an anchor for the plated layer as well as an electroless plating catalyst. The plated fibers also possessed electrical conductivity. Although the tensile strength of the Zylon fiber decreased from 5.8 to 4.9 GPa after undergoing the pretreatment and plating processes, the light shielding effect improved the light resistance of the plated fibers in terms of tensile properties. After 18 days of xenon lamp exposure, the plated fibers retained 74% of its initial strength, whereas that of untreated fibers decreased to 43%.

  3. Highly adhesive metal plating on Zylon fiber via iodine pretreatment

    International Nuclear Information System (INIS)

    Highly adhesive metal plating was performed on poly(p-phenylene-2,6-benzobisoxazole) fiber named Zylon via iodine pretreatment followed by electroless plating. First, iodine components were selectively doped into the inner part of the fiber near the surface through iodine vapor exposure. The doped iodine was converted to palladium iodide particles by treating with palladium chloride solution. After the reduction of the iodide to metal palladium particles, electroless copper plating was conducted on the fiber. A uniform copper layer was deposited on the fiber surface and exhibited high durability in durability tests such as ultrasonic exposure, tape peeling-off, and corrosion in NaCl solution. This durability was attributed to the palladium particles formed at the fiber surface that served as an anchor for the plated layer as well as an electroless plating catalyst. The plated fibers also possessed electrical conductivity. Although the tensile strength of the Zylon fiber decreased from 5.8 to 4.9 GPa after undergoing the pretreatment and plating processes, the light shielding effect improved the light resistance of the plated fibers in terms of tensile properties. After 18 days of xenon lamp exposure, the plated fibers retained 74% of its initial strength, whereas that of untreated fibers decreased to 43%.

  4. Studies of nanocrystalline Pd alloy films coated by electroless deposition

    International Nuclear Information System (INIS)

    The microstructures of thin coating films of pure palladium and palladium alloys deposited from organic electrolytes onto different metallic substrates by electroless plating method have been investigated. The coatings are dense, pore-free 0.005-1 μm thick films with high adhesive strength to the substrate surface. X-ray spectral analysis, X-ray phase analysis, transmission and scanning electron microscopy were used to determine the composition and structure of alloy coatings of binary systems: Pd-Au, Pd-Ag, Pd-Ni, Pd-Pb, and ternary system Pd-Au-Ni. The coatings of Pd-Au, Pd-Ag, and Pd-Ni have a solid solution structure, whereas Pd-Pb is intermetallic compound. It has been found that the deposited films consist of nanocrystalline grains with sizes in the range of 11-35 nm. Scanning and transmission electron microscopy investigations reveal the existence of clusters formed by nanocrystalline grains. The origin for the formation of nanocrystalline structures of coating films is discussed.

  5. Polyaniline films containing electrolessly precipitated palladium

    International Nuclear Information System (INIS)

    Polyaniline (PAni) films with similar electroactivity were potentiodynamically grown at selected different scan rates and number of cycles. Palladium particles were incorporated in the electroactive polymer by electroless precipitation. The polymeric matrix morphology and its effect on the distribution and size of Pd particles was analysed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). It was observed that the dispersion of metal clusters was imparted by the nature of the polymer matrix. The results allowed to state a correlation between the polymer topography and the size and spatial distribution of the catalytic particles

  6. Comparative Study of Electroless Copper Film on Different Self-Assembled Monolayers Modified ABS Substrate

    Directory of Open Access Journals (Sweden)

    Jiushuai Xu

    2014-04-01

    Full Text Available Copper films were grown on (3-Mercaptopropyltrimethoxysilane (MPTMS, (3-Aminopropyltriethoxysilane (APTES and 6-(3-(triethoxysilylpropylamino-1,3,5- triazine-2,4-dithiol monosodium (TES self-assembled monolayers (SAMs modified acrylonitrile-butadiene-styrene (ABS substrate via electroless copper plating. The copper films were examined using scanning electron microscopy (SEM and X-ray diffraction (XRD. Their individual deposition rate and contact angle were also investigated to compare the properties of SAMs and electroless copper films. The results indicated that the formation of copper nuclei on the TES-SAMs modified ABS substrate was faster than those on the MPTMS-SAMs and APTES-SAMs modified ABS substrate. SEM images revealed that the copper film on TES-SAM modified ABS substrate was smooth and uniform, and the density of copper nuclei was much higher. Compared with that of TES-SAMs modified resin, the coverage of copper nuclei on MPTMS and APTES modified ABS substrate was very limited and the copper particle size was too big. The adhesion property test demonstrated that all the SAMs enhanced the interfacial interaction between copper plating and ABS substrate. XRD analysis showed that the copper film deposited on SAM-modified ABS substrate had a structure with Cu(111 preferred orientation, and the copper film deposited on TES-SAMs modified ABS substrate is better than that deposited on MPTMS-SAMs or APTES-SAMs modified ABS resins in electromigrtion resistance.

  7. Characterization of electroless nickel as a seed layer for silicon solar cell metallization

    Indian Academy of Sciences (India)

    Mehul C Raval; Chetan S Solanki

    2015-02-01

    Electroless nickel plating is a suitable method for seed layer deposition in Ni–Cu-based solar cell metallization. Nickel silicide formation and hence contact resistivity of the interface is largely influenced by the plating process and annealing conditions. In the present work, a thin seed layer is deposited from neutral pH and alkaline electroless nickel baths which are annealed in the range of 400–420°C for silicide morphology and contact resistivity studies. A minimum contact resistivity of 7 m cm2 is obtained for seed layer deposited from alkaline bath. Silicide formation for Pd-activated samples leads to uniform surface morphology as compared with unactivated samples due to non-homogeneous migration of nickel atoms at the interface. Formation of nickel phosphides during annealing and the presence of SiO2 at Ni–Si interface creates isolated Ni2Si–Si interface with limited supply of silicon. Such an interface leads to the formation of high resistivity metal-rich Ni3Si silicide phase which limits the reduction in contact resistivity.

  8. Thermophysical properties and microstructure of graphite flake/copper composites processed by electroless copper coating

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Qian; He, Xin-Bo; Ren, Shu-Bin; Zhang, Chen; Ting-Ting, Liu; Qu, Xuan-Hui, E-mail: quxh@ustb.edu.cn

    2014-02-25

    Highlights: • GF–copper composites were fabricated using a sparking plasma sintering, which involves coating GF with copper, using electroless plating technique. • The oriented graphite flake distributed homogeneously in matrix. • With the increase of flake graphite from 44 to 71 vol.%, the basal plane thermal conductivity of composites increases from 445 to 565 W m{sup −1} K{sup −1} and the thermal expansion of composites decreases from 8.1 to 5.0. • The obtained composites are suitable for electronic packaging materials. -- Abstract: This study focuses on the fabrication of thermal management material for power electronics applications using graphite flake reinforced copper composites. The manufacturing route involved electroless plating of copper on the graphite flake and further spark plasma sintering of composite powders. The relative density of the composites with 44–71 vol.% flakes achieved up to 98%. Measured thermal conductivities and coefficients of thermal expansion of composites ranged from 455–565 W m{sup −1} K{sup −1} and 8 to 5 ppm K{sup −1}, respectively. Obtained graphite flake–copper composites exhibit excellent thermophysical properties to meet the heat dispersion and matching requirements of power electronic devices to the packaging materials.

  9. Microstructure and mechanical properties of Ni-P-Si3N4 nanowire electroless composite coatings

    Science.gov (United States)

    Wang, Shilong; Huang, Xuefei; Gong, Mengxiao; Huang, Weigang

    2015-12-01

    In this paper, a new Ni-P-Si3N4 nanowire composite coating has been successfully prepared on AZ31 Mg substrate through electroless deposition technique. The effect of Si3N4 nanowire concentration in the plating bath on the surface morphology, hardness and wear behavior of the composite coatings have been investigated. The results show that when the concentrations of Si3N4 nanowire is 1.5 g/L, the morphology of composite coating appears the fine nodular structure. Moreover, the Si3N4 nanowire is uniformly dispersed in the coating at the 1.5 g/L concentrations of Si3N4 nanowire. But when the concentrations of Si3N4 nanowire in bath over 1.5 g/L, the coatings surface morphology become roughness and some pores appear on the coating surface because of the agglomeration of Si3N4 nanowire. As seen from the experiments results, the microhardness of the composite coating were significantly increased to about 790HV200 as plating, the friction coefficient and wear weight loss of the composite coating is both decreased to the 1/6 of conventional Ni-P electroless coating. These improvements have been attributed to the dispersion strengthening effect of Si3N4 nanowire.

  10. ELECTROLESS NICKEL DEPOSITION ON FRAXINUS MANDSHURICA VENEER MODIFIED WITH APTHS FOR EMI SHIELDING

    Directory of Open Access Journals (Sweden)

    Haibing Liu

    2010-08-01

    Full Text Available Electroless nickel deposition was carried out on Fraxinus mandshurica veneers for EMI shielding under a new activation process. In the process, Pd(II was absorbed on the surface of veneers modified with γ-aminopropyltrihydroxysilane (APTHS obtained from the hydrolysis of γ-aminopropyltriethoxysilane (APTES. After the reduction, electroless plating was successfully initiated, and Ni-P coating was deposited on the veneers. The activation process and resulting coating were characterized by XPS, SEM-EDS, and XRD. The metal deposition, surface resistivity, and electromagnetic shielding effectiveness were measured. XPS analysis proved that Pd(II was bonded to the amino group of APTHS and reduced to Pd(0. The coating was continuous, uniform, and compact. It consisted of 97.4 wt% nickel and 2.6 wt% phosphorus. XRD analysis showed that the coating was crystalline, which was related to the low phosphorus content. The plated Fraxinus mandshurica veneers exhibit good electro-conductivity with surface resistivity of 0.21Ω•cm-2 and higher electromagnetic shielding effectiveness of over 50dB in frequencies from 10 MHz to 1.5 GHz.

  11. Electroless nickel alloy deposition on SiO2 for application as a diffusion barrier and seed layer in 3D copper interconnect technology.

    Science.gov (United States)

    Kim, Tae-Yoo; Son, Hwa-Jin; Lim, Seung-Kyu; Song, Young-Il; Park, Hwa-Sun; Suh, Su-Jeong

    2014-12-01

    Electroless Ni-P films were investigated with the aim of application as barrier and seed layers in 3D interconnect technology. Different shapes of blind-via holes were fabricated with a deep reactive ion etcher and SiO2 formed on these holes as an insulating layer. The surface of the substrate has been made hydrophilic by O2 plasma treatment with 100 W of power for 20 min. Electroless Ni-P films were deposited as both a diffusion barrier and a seed layer for Cu filling process. Prior to plating, substrates were activated in a palladium chloride solution after sensitization in a tin chloride solution with various conditions in order to deposit uniform films in TSV. After the formation of the electroless barrier layer, electro Cu was plated directly on the barrier layer. Ni-P films fabricated in blind-via holes were observed by scanning electron microscope. Energy dispersive spectroscopy line scanning was carried out for evaluating the diffusion barrier properties of the Ni-P films. The electroless Ni-P layer worked well as a Cu diffusion barrier until 300 degrees C. However, Cu ions diffused into barrier layer when the annealing temperature increases over 400 degrees C. PMID:25971093

  12. Effect of copper-plating on hydrogen storage performance of a La-Ni-Al metal hydride

    Energy Technology Data Exchange (ETDEWEB)

    Bin Liao [Academy of Sciences, Shenyang (China). Inst. of Metal Research]|[Inst. of Structural Michanics, Chinese Academy of Engineering Physics, Mianyang (China); Manqi Lu; Ke Yang [Academy of Sciences, Shenyang (China). Inst. of Metal Research; Dehui Zhou; Ying Fan; Xun Yang; Yun Tan [Inst. of Structural Michanics, Chinese Academy of Engineering Physics, Mianyang (China)

    2001-07-01

    Metal hydride compacts were prepared by compressing LaNi{sub 4.75}Al{sub 0.25} alloy powders with copper chemical plating or copper acidic electroless plating. The compacts show a remarkable improvement on the hydrogen desorption rate, compared to the powders before plating. The thermal diffusion coefficient of the metal hydride compacts are 10-15 times higher than that of the LaNi{sub 5} bulk and the compacts show no obvious breaks after 10 absorption-desorption cycles. Copper plating has no effect on the thermodynamics as well as the phase structure of the matrix alloy. The plating copper layer prepared by acidic electroless plating has poor plasticity and poor pulverization-resistance because it is a mixture of copper and the matrix. The hydrogen storage capacity of matrix is much reduced after acidic electroless plating because the matrix elements are replaced by the copper and then dissolved during plating. While the copper layer prepared by chemical-plating shows good pulverization-resistance, the plated powders have less loss of hydrogen storage capacity than that of acidic electroless plating. (orig.)

  13. Effect of heat treatment, top coatings and conversion coatings on the corrosion properties of black electroless Ni-P films

    International Nuclear Information System (INIS)

    Electroless black nickel-phosphorus plating is an advanced electroless nickel plating process formulated to deposit a black finish when processed through an oxidizing acid solution. Heat treatment, five types of top organic coating techniques and one conversion coating technique with three different experimental conditions were investigated to stabilize the black film and increase the hardness and corrosion resistance. Morphology and compositions of electroless nickel-phosphorous films with or without heat treatment, with five types of top organic coatings, and with three conversion coatings were compared to examine nickel, phosphorus, oxygen, carbon, silicon and chrome contents on the corrosion resistance of black surfaces by energy dispersive X-ray microanalysis and scanning electron microscope. Corrosion resistance of black electroless nickel-phosphorus coatings with or without heat treatment, with five types of top organic coatings, and with three conversion coatings was investigated by the polarization measurements and the salt spray test in 5% NaCl solution, respectively. HydroLac as the top organic coating from MacDermid showed the excellent corrosion resistance and the black EN film did not lose the black color after 48 h salt spray test. Electrotarnil B process with 0.5 ASD for 1 min stabilized the black Ni-P film immediately and increased the hardness and corrosion performance of the black Ni-P film. The black Ni-P coating with Electroarnil B process passed the 5% NaCl salt spray test for 3000 h in the black color and had a minimal corrosion current 0.8547 μA/cm2 by the polarization measurement.

  14. Effect of temperature on structure and corrosion resistance for electroless NiWP coating

    Indian Academy of Sciences (India)

    M Q YU; Q QIAO; F YOU; C L LI; Y ZHAO; Z Z XIAO; H L LUO; Z F XU; KAZUHIRO MATSUGI; J K YU

    2016-04-01

    The effect of plating temperatures between 60 and 90$^{\\circ}$C on structure and corrosion resistance for electroless NiWP coatings on AZ91D magnesium alloy substrate was investigated. Results show that temperature has a significant influence on the surface morphology and corrosion resistance of the NiWP alloy coating. An increase in temperature will lead to an increase in coating thickness and form a more uniform and dense NiWP coatings. Moreover, cracks were observed by SEM in coating surface and interface at the plating temperature of 90$^{\\circ}$C. Coating corrosion resistance is highly dependent on temperature according to polarization curves. The optimum temperature isfound to be 80$^{\\circ}$C and the possible reasons of corrosion resistance for NiWP coating have been discussed.

  15. Effects of catalyst introduction methods using PAMAM dendrimers on selective electroless nickel deposition on polyelectrolyte multilayers.

    Science.gov (United States)

    Hendricks, Troy R; Dams, Erin E; Wensing, Steven T; Lee, Ilsoon

    2007-06-19

    We studied the effects of catalyst introduction methods using poly(amidoamine) (PAMAM) dendrimers on the nickel patterning of polyelectrolyte multilayer (PEM)-coated substrates. Three different approaches to palladium catalyst introduction using microcontact printing as the patterning technique were utilized and compared. The catalyst introduction methods are (1) direct catalyst stamping, (2) directed assembly using PAMAM dendrimer stamping, and (3) catalyst encapsulation and reduction to nanoparticles within PAMAM dendrimers before stamping. After patterning, the sample surfaces were placed in an electroless bath where nickel was selectively plated onto the patterns. The patterned surfaces were characterized using optical microscopy, atomic force microscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The metal plating rates on different homogeneous surfaces that simulate the patterned surfaces were measured using a quartz crystal microbalance. In addition, the effect of PEM film thickness (i.e., number of bilayers) on the selectivity of nickel patterning was investigated. PMID:17523692

  16. Recovery of deuterium from argon carrier gas by ZrNi modified with electroless Pd coating

    International Nuclear Information System (INIS)

    The effectiveness of Pd-coating on ZrNi against impurity gas exposure was examined. X-ray diffraction profiles revealed that the surfaces of plate and grain samples are readily covered with Pd by electroless plating. Mutual diffusion between the Pd-overlayer and the ZrNi substrate and PdZr formation took place by vacuum heating above 973 K. Deuterium recovery (DR) in a flowing argon carrier gas containing 5 ppm of impurity gases was examined using packed columns of bare ZrNi and Pd/ZrNi grains. Results indicate that the Pd-coating successfully extends the life time of ZrNi against impurity gases at low temperature below 473 K. Furthermore, no noticeable reduction in DR was found in Pd/ZrNi, whereas bare ZrNi loss its activity at 10 ks at 573 K. (author)

  17. GaN Nanowires Synthesized by Electroless Etching Method

    KAUST Repository

    Najar, Adel

    2012-01-01

    Ultra-long Gallium Nitride Nanowires is synthesized via metal-electroless etching method. The morphologies and optical properties of GaN NWs show a single crystal GaN with hexagonal Wurtzite structure and high luminescence properties.

  18. Brazing with plated alloys

    International Nuclear Information System (INIS)

    The use of braze alloy preforms on complex geometry components is at times a very difficult task requiring extensive handling of the parts or even tack welding of the preform to ensure that it is held in place. One method of overcoming these difficulties is the use of plated braze alloys (i.e., filler metals) applied directly to the braze region. Plating helps to avoid the potential for contamination resulting from handling and also ensures that the braze alloy is located properly. Examples are discussed in which an electroplated silver-copper alloy is used as an alternative to the BAg8 preforms and electroless nickel is used as a replacement for an amorphous Ni-P braze alloy foil. A toroidal cooling plate with helical flow channels was fabricated from oxygen-free high conductivity (OFHC) and brazed using the electroplated silver-copper alloy. The silver-copper braze alloy was applied to the copper substrate in a laminated fashion of alternating layers of silver and copper, which in combination approximated the eutectic composition (72% Ag-28% Cu by weight). Examination of the brazed assemblies indicated that in both cases the advantages of using plated braze alloys are numerous. These advantages include decreased labor, improved cleanliness and exactness of braze alloy placement. The primary disadvantage was an increased tendency for solidification defects presumably resulting from contaminants in the plating baths. This last observation is presently being examined in greater detail. The end results is that the assemblies brazed with the plated alloys were acceptable for the intended application and that the use of plating facilitated the successful assembly of these components

  19. Electroless Fabrication of Cobalt Alloys Nanowires within Alumina Template

    OpenAIRE

    Nazila Dadvand; Kipouros, Georges J.

    2007-01-01

    A new method of nanowire fabrication based on electroless deposition process is described. The method is novel compared to the current electroless procedure used in making nanowires as it involves growing nanowires from the bottom up. The length of the nanowires was controlled at will simply by adjusting the deposition time. The nanowires were fabricated within the nanopores of an alumina template. It was accomplished by coating one side of the template by a thin layer of palladium in order t...

  20. Enhancement of the corrosion protection of electroless Ni–P coating by deposition of sonosynthesized ZnO nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Sharifalhoseini, Zahra [Sonochemical Research Center, Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, 91779 Mashhad (Iran, Islamic Republic of); Entezari, Mohammad H., E-mail: entezari@um.ac.ir [Sonochemical Research Center, Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, 91779 Mashhad (Iran, Islamic Republic of); Environmental Chemistry Research Center, Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, 91779 Mashhad (Iran, Islamic Republic of)

    2015-10-01

    Graphical abstract: Enhancement of the corrosion protection of electroless Ni–P layer by ZnO nanoparticles deposition and the comparison with the classical and sonochemical Ni–P coatings. - Highlights: • Unique effects of ultrasound were investigated on the anticorrosive performance of electroless Ni–P coating. • Sonoynthesis of ZnO NPs and its deposition were performed on the surface of Ni–P coating. • ZnO as an anticorrosive has a critical role in the multifunctional surfaces. • Electrochemical properties of all fabricated samples were compared with each other. - Abstract: Ni–P coatings were deposited through electroless nickel plating in the presence and absence of ultrasound. The simultaneous synthesis of ZnO nanoparticle and its deposition under ultrasound were also carried out on the surface of Ni–P layer prepared by the classical method. The morphology of the surfaces and the chemical composition were determined by scanning electron microscopy(SEM) and energy dispersive spectroscopy (EDS), respectively. Electrochemical techniques were applied for the corrosion behavior studies. The Ni–P layer deposited by ultrasound showed a higher anticorrosive property than the layer deposited by the classical method. The ZnO nanoparticles deposited on the surface of Ni–P layer significantly improved the corrosion resistance.

  1. Tribological characteristics of electroless Ni-P-MoS{sub 2} composite coatings at elevated temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Li Zhen; Wang Jingbo; Lu Jinjun [State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Meng Junhu, E-mail: jhmeng@licp.cas.cn [State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000 (China)

    2013-01-01

    Highlights: Black-Right-Pointing-Pointer Uniform Ni-P-MoS{sub 2} composite coatings are deposited by electroless plating. Black-Right-Pointing-Pointer Friction coefficient of composite coating decreases with the increase of temperature. Black-Right-Pointing-Pointer Formation of lubricious oxide film leads to excellent tribological property. - Abstract: Ni-P-MoS{sub 2} composite coatings were deposited on AISI-1045 steel plate by electroless plating followed by a heat treatment at 300 Degree-Sign C for 2 h. The high-temperature tribological characteristics of the composite coatings were evaluated under dry sliding conditions in a tribometer with ball-on-disk configuration. The effect of the co-deposition of MoS{sub 2} on the friction and wear behaviors of composite coatings at elevated temperature was investigated. Scanning electron microscopy was used to determine the morphology of the worn surface of composite coating. The chemical states of some typical elements on the worn surfaces were determined by X-ray photoelectron spectroscope. The results indicate that friction coefficient of the composite coatings decreases with the increase of test temperature up to 500 Degree-Sign C, and the best tribological properties of Ni-P-MoS{sub 2} composite coatings are achieved at 400 Degree-Sign C. The worn surface of Ni-P-MoS{sub 2} composite coatings are characterized by mild scuffing and deformation. The improvement of tribological properties of the composite coatings was attributed to the formation of the lubricious oxide film composed of oxides of Ni and Mo at high temperatures. With the test temperature increasing to 600 Degree-Sign C, the tribological properties of the composite coating begin to deteriorate due to softening of the coating.

  2. The pH-sensitive Pd nanoparticles as ink for ink-jet printing technology and electroless Cu metallic patterns on indium-doped tin oxide substrate

    International Nuclear Information System (INIS)

    In this work, a method to fabricate copper pattern on an indium-doped tin oxide (ITO) glass substrate is described. This method involves ink-jet printing of a pH-sensitive chitosan-g-polyvinyl acetate/Pd nanoparticle (CTS-g-PVAc-Pd) based ink on an untreated ITO plate to create the catalytic sites, onto which copper is subsequently deposited by an electroless plating method. To prepare the CTS-g-PVAc-Pd nanoparticles, a pH-sensitive chitosan-g-polyvinyl acetate (CTS-g-PVAc) copolymer is utilized to self-reduce Pd nanoparticles. The pH-sensitive CTS chains function as stabilizing agent for noble metal nanoparticles in acidic ink solution. On the other hand, CTS-g-PVAc copolymers convert to hydrophilic CTS-g-poly(vinyl alcohol) via alkali hydrolysis during the electroless copper plating. Therefore, the copper film with dramatically enhanced adhesion is formed on the surface of ITO glass without special pretreatment step before electroless deposition of copper film. Our results show that this process yields copper line with width down to 60 μm and ITO plated with the copper coating has good electrical conductivity, with an electrical resistivity of about 5.4 μΩ cm. - Highlights: • Chitosan-g-polyvinyl acetate copolymer provides reducing environment for Pd nanoparticles. • pH-sensitive Pd nanoparticles as ink for ink-jet printing. • Patterning Pd catalyst for the electroless deposition of copper patterns. • Method to fabricate copper patterns on In-doped tin oxide substrates. • Ink-jet printing can be directly and easily applied to fabricate metal patterns

  3. The pH-sensitive Pd nanoparticles as ink for ink-jet printing technology and electroless Cu metallic patterns on indium-doped tin oxide substrate

    Energy Technology Data Exchange (ETDEWEB)

    Tseng, Chun-Chieh; Lin, Yi [Medical Device Section, Medical Devices and Opto-Electronics Equipment Department, Metal Industries Research and Development Centre, Kaohsiung 802, Taiwan (China); Liu, Tsai-Yun [Department of Mechanical Engineering and Graduate Institute of Mechanical and Precision Engineering, National Kaohsiung University of Applied Sciences, Kaohsiung 807, Taiwan (China); Nian, Yan-Yu [Graduate School of Defense Science, Chung Cheng Institute of Technology, National Defense University, 335 Taiwan (China); Wang, Min-Wen, E-mail: mwwang@cc.kuas.edu.tw [Department of Mechanical Engineering and Graduate Institute of Mechanical and Precision Engineering, National Kaohsiung University of Applied Sciences, Kaohsiung 807, Taiwan (China); Ger, Ming-Der, E-mail: mingderger@gmail.com [Department of Chemical and Materials Engineering, Chung Cheng Institute of Technology, National Defense University, 335 Taiwan (China)

    2013-06-01

    In this work, a method to fabricate copper pattern on an indium-doped tin oxide (ITO) glass substrate is described. This method involves ink-jet printing of a pH-sensitive chitosan-g-polyvinyl acetate/Pd nanoparticle (CTS-g-PVAc-Pd) based ink on an untreated ITO plate to create the catalytic sites, onto which copper is subsequently deposited by an electroless plating method. To prepare the CTS-g-PVAc-Pd nanoparticles, a pH-sensitive chitosan-g-polyvinyl acetate (CTS-g-PVAc) copolymer is utilized to self-reduce Pd nanoparticles. The pH-sensitive CTS chains function as stabilizing agent for noble metal nanoparticles in acidic ink solution. On the other hand, CTS-g-PVAc copolymers convert to hydrophilic CTS-g-poly(vinyl alcohol) via alkali hydrolysis during the electroless copper plating. Therefore, the copper film with dramatically enhanced adhesion is formed on the surface of ITO glass without special pretreatment step before electroless deposition of copper film. Our results show that this process yields copper line with width down to 60 μm and ITO plated with the copper coating has good electrical conductivity, with an electrical resistivity of about 5.4 μΩ cm. - Highlights: • Chitosan-g-polyvinyl acetate copolymer provides reducing environment for Pd nanoparticles. • pH-sensitive Pd nanoparticles as ink for ink-jet printing. • Patterning Pd catalyst for the electroless deposition of copper patterns. • Method to fabricate copper patterns on In-doped tin oxide substrates. • Ink-jet printing can be directly and easily applied to fabricate metal patterns.

  4. Preparation and Study of Electromagnetic Interference Shielding Materials Comprised of Ni-Co Coated on Web-Like Biocarbon Nanofibers via Electroless Deposition

    OpenAIRE

    Xiaohu Huang; Bo Dai; Yong Ren; Jing Xu; Pei Zhu

    2015-01-01

    Electromagnetic interference (EMI) shielding materials made of Ni-Co coated on web-like biocarbon nanofibers were successfully prepared by electroless plating. Biocarbon nanofibers (CF) with a novel web-like structure comprised of entangled and interconnected carbon nanoribbons were obtained using bacterial cellulose pyrolyzed at 1200°C. Paraffin wax matrix composites filled with different loadings (10, 20, and 30 wt%, resp.) of CF and Ni-Co coated CF (NCCF) were prepared. The electrical cond...

  5. Mechanism of adhesion of electroless-deposited silver on poly(ether urethane)

    Energy Technology Data Exchange (ETDEWEB)

    Gray, J.E. [Department of Chemistry and Biochemistry, Laurentian University, 935 Ramsey Lake Road Sudbury, Ontario, P3E 2C6 (Canada)]. E-mail: jgray@laurentian.ca; Norton, P.R. [Department of Chemistry and Interface Science Western, University of Western Ontario, London, Ontario, N6A 5B (Canada)]. E-mail: pnorton@uwo.ca; Griffiths, K. [Department of Chemistry and Interface Science Western, University of Western Ontario, London, Ontario, N6A 5B (Canada)

    2005-07-22

    Bacterial growth on medical implants and devices is a common source of infection. There is a great deal of interest in the surface modification of polymeric materials to decrease infection rates without altering properties that affect their function. One possibility is to coat the material with an antibacterial agent such as silver. This paper explores the feasibility of depositing adherent silver films onto biomedical poly(ether urethanes) by an electroless plating process. The surface chemistry of the deposition process and the effect of a plasma treatment on the metal/polymer adhesion have been explored. The silver films produced on an unmodified poly(ether urethane) surface consist predominantly of micron-sized clusters that form in solution and are poorly adhered to the surface. However, some small adherent clusters are also deposited on the polymer surface and X-ray photoelectron spectroscopy of the metal/polymer interface shows evidence of chemical interaction between silver and surface carbonyl groups. An air plasma treatment of the polymer to increase the number of carbonyl containing groups at the surface has been shown to significantly improve the metal/polymer adhesion and to decrease the porosity of the silver films. This paper illustrates the importance of chemical bonding in the electroless metallization of polymers.

  6. Preparation and in-vitro Antibacterial Evaluation of Electroless Silver Coated Polymers.

    Science.gov (United States)

    Fazeli, Mohammad Reza; Hosseini, Vahid; Shamsa, Fazel; Jamalifar, Hossein

    2010-01-01

    Long-term use of indwelling medical catheters has often been hindered by catheter-associated nosocomial infections. In this study the effectiveness of silver coating of polystyrene and polyethylene polymers was investigated. Polymer pieces of 2 cm(2) each were coated with a thin layer of silver using electroless plating technique. Silver-coated polymers were challenged with cultures of four different microorganisms known for their involvement in nosocomial infections in both solid and broth media. The tested bacteria included Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli and Pseudomonas aeruginosa. Silver release from the coated polymers was 2-5 μg/cm(2) which was confirmed by chemical and biological methods. The silver coating thickness ranged between 20-450 nm. P. aeruginosa and S. aureus were the most adherent bacteria to polystyrene sheets while E. coli showed minimum adherence effect. The survival rate of different bacteria after 80 min in a time course experiment tended to dominate E. coli as the most sensitive bacteria to the effect of silver with zero survival rate while around 4% of P. aeruginosa were detected after same period. Silver coating of indwelling polymers by electroless technique seems promising in combating nosocomial infections due to long-term catheterization. PMID:24363735

  7. Mechanism of adhesion of electroless-deposited silver on poly(ether urethane)

    International Nuclear Information System (INIS)

    Bacterial growth on medical implants and devices is a common source of infection. There is a great deal of interest in the surface modification of polymeric materials to decrease infection rates without altering properties that affect their function. One possibility is to coat the material with an antibacterial agent such as silver. This paper explores the feasibility of depositing adherent silver films onto biomedical poly(ether urethanes) by an electroless plating process. The surface chemistry of the deposition process and the effect of a plasma treatment on the metal/polymer adhesion have been explored. The silver films produced on an unmodified poly(ether urethane) surface consist predominantly of micron-sized clusters that form in solution and are poorly adhered to the surface. However, some small adherent clusters are also deposited on the polymer surface and X-ray photoelectron spectroscopy of the metal/polymer interface shows evidence of chemical interaction between silver and surface carbonyl groups. An air plasma treatment of the polymer to increase the number of carbonyl containing groups at the surface has been shown to significantly improve the metal/polymer adhesion and to decrease the porosity of the silver films. This paper illustrates the importance of chemical bonding in the electroless metallization of polymers

  8. Electroless deposition of a Ag matrix on semiconducting one-dimensional nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Miguel, F.L., E-mail: f.miguel@mx.uni-saarland.de [Saarland University, Chair of Functional Materials, 66123, Saarbrücken (Germany); Shen, H. [University of Cologne, Chair of Inorganic and Materials Chemistry, 50939, Cologne (Germany); Soldera, F. [Saarland University, Chair of Functional Materials, 66123, Saarbrücken (Germany); Fischer, T.; Müller, R.; Mathur, S. [University of Cologne, Chair of Inorganic and Materials Chemistry, 50939, Cologne (Germany); Mücklich, F. [Saarland University, Chair of Functional Materials, 66123, Saarbrücken (Germany)

    2013-06-01

    Composite materials consisting of one-dimensional semiconducting nanostructures embedded in a Ag matrix were produced. The regarded nanostructures are hydrothermally grown TiO{sub 2} nanorods and SnO{sub 2} nanowires obtained by chemical vapor deposition with a vapor–liquid–solid growth process. The Ag was deposited by means of electroless plating, for which AgNO{sub 3} was employed as the Ag{sup +} source and a glucose-based aqueous solution as the reducing agent. Cross-section micrographs obtained through scanning electron microscopy show homogeneous and compact Ag coatings, which penetrated down to the substrate level filling the space between the oxide structures. Additionally, the SnO{sub 2} composite was analyzed by focused ion beam nanotomography with a measured porosity of 0.1%. The obtained materials are potential candidates for electrical contacts applications. - Highlights: • Nanocomposite fabrication: TiO{sub 2} and SnO{sub 2} 1D-nanostructures in silver matrix • Electroless deposition: narrow voids filled and accurate topography reproduction • Ag–SnO{sub 2} composite: remarkably low porosity content achieved (0.09%) • Additionally, small sized pores: 80% no larger than 20 nm.

  9. Electroless deposition of a Ag matrix on semiconducting one-dimensional nanostructures

    International Nuclear Information System (INIS)

    Composite materials consisting of one-dimensional semiconducting nanostructures embedded in a Ag matrix were produced. The regarded nanostructures are hydrothermally grown TiO2 nanorods and SnO2 nanowires obtained by chemical vapor deposition with a vapor–liquid–solid growth process. The Ag was deposited by means of electroless plating, for which AgNO3 was employed as the Ag+ source and a glucose-based aqueous solution as the reducing agent. Cross-section micrographs obtained through scanning electron microscopy show homogeneous and compact Ag coatings, which penetrated down to the substrate level filling the space between the oxide structures. Additionally, the SnO2 composite was analyzed by focused ion beam nanotomography with a measured porosity of 0.1%. The obtained materials are potential candidates for electrical contacts applications. - Highlights: • Nanocomposite fabrication: TiO2 and SnO2 1D-nanostructures in silver matrix • Electroless deposition: narrow voids filled and accurate topography reproduction • Ag–SnO2 composite: remarkably low porosity content achieved (0.09%) • Additionally, small sized pores: 80% no larger than 20 nm

  10. Electroless Ni-B-W coatings for improving hardness, wear and corrosion resistance: Nanašanje Ni-B-W s cementacijskim galvaniziranjem za izboljšavo trdote, obrabe in odpornosti proti koroziji:

    OpenAIRE

    Aydeniz, Ali Imre; Calli, Cagdas; Dil, Gökce; Göksenli, Ali; MUHAFFEL, Faiz; Yüksel, Behiye

    2013-01-01

    In this study the formation of a Ni-B-W coating on steel using an electroless plating process and evaluation of the hardness, wear and corrosion resistance was analyzed. The Ni-B-W coating was prepared using an alkaline borohydride-reduced electroless nickel bath. Scanning electron microscopy (SEM) of the cross-sectional view of the Ni-B-W coating was analyzed and the layer characteristics were investigated. The Ni-B-W coating was characterized using XRD. The study reveals that the Ni-B-W coa...

  11. Effect of Processing Parameters on the Protective Quality of Electroless Nickel-Phosphorus on Cast Aluminium Alloy

    OpenAIRE

    Olawale Olarewaju Ajibola; Daniel Toyin Oloruntoba; Adewuyi, Benjamin O.

    2015-01-01

    The effects of temperature, pH, and time variations on the protective amount and quality of electroless nickel (EN) deposition on cast aluminium alloy (CAA) substrates were studied. The temperature, pH, and plating time were varied while the surface condition of the substrate was kept constant in acid or alkaline bath. Within solution pH of 5.0–5.5 range, the best quality is obtained in acid solution pH of 5.2. At lower pH (5.0–5.1), good adhesion characterised the EN deposition. Within the r...

  12. High-temperature measurement using Cu-plating fiber Bragg grating for metal smart structure applications

    Science.gov (United States)

    Chang, Tianying; Jia, Lei; Sui, Qingmei; Cui, Hong-Liang

    2014-03-01

    High-temperature experiments for electroless Cu-plating Fiber Bragg Grating (FBG) indicate that Cu-plating FBG can measure high-temperature up to (even beyond) 300°C and it has high linearity, accuracy and repeatability. We can control Cu-plating FBG's temperature sensitivity by controlling plating layer's thickness. Temperature sensitivity of FBG with Cu-plating can be improved by more than three times with no less than 300μmthick coating by electroless and electrical Cu-plating. Such FBG can be soldered onto metal structures to get good bonding with the structure. As a result, such fiber sensors can get good protection, and high-temperature monitoring of smart structure is obtained.

  13. Ligand-optimized electroless synthesis of silver nanotubes and their activity in the reduction of 4-nitrophenol

    Energy Technology Data Exchange (ETDEWEB)

    Muench, Falk; Rauber, Markus; Stegmann, Christian; Lauterbach, Stefan; Kunz, Ulrike; Kleebe, Hans-Joachim; Ensinger, Wolfgang, E-mail: muench@ca.tu-darmstadt.de [Department of Materials and Geoscience, Technische Universitaet Darmstadt, Petersenstrasse 23, 64287 Darmstadt (Germany)

    2011-10-14

    A facile electroless plating procedure for the controlled synthesis of nanoscale silver thin films and derived structures such as silver nanotubes was developed and the products were characterized by SEM, TEM and EDS. The highly stable plating baths consist of AgNO{sub 3} as the metal source, a suitable ligand and tartrate as an environmentally benign reducing agent. Next to the variation of the coordinative environment of the oxidizing component, the influence of the pH value was evaluated. These two governing factors strongly affect the plating rate and the morphology of the developing silver nanoparticle films and can be used to adapt the reaction to synthetic demands. The refined electroless deposition allows the fabrication of homogeneous high aspect-ratio nanotubes in ion track etched polycarbonate. Template-embedded metal nanotubes can be interpreted as parallelled microreactors. Following this concept, both the silver nanotubes and spongy gold nanotubes obtained by the use of the silver structures as sacrificial templates were applied in the reduction of 4-nitrophenol by sodium borohydride, proving to be extraordinarily effective catalysts.

  14. Ligand-optimized electroless synthesis of silver nanotubes and their activity in the reduction of 4-nitrophenol

    International Nuclear Information System (INIS)

    A facile electroless plating procedure for the controlled synthesis of nanoscale silver thin films and derived structures such as silver nanotubes was developed and the products were characterized by SEM, TEM and EDS. The highly stable plating baths consist of AgNO3 as the metal source, a suitable ligand and tartrate as an environmentally benign reducing agent. Next to the variation of the coordinative environment of the oxidizing component, the influence of the pH value was evaluated. These two governing factors strongly affect the plating rate and the morphology of the developing silver nanoparticle films and can be used to adapt the reaction to synthetic demands. The refined electroless deposition allows the fabrication of homogeneous high aspect-ratio nanotubes in ion track etched polycarbonate. Template-embedded metal nanotubes can be interpreted as parallelled microreactors. Following this concept, both the silver nanotubes and spongy gold nanotubes obtained by the use of the silver structures as sacrificial templates were applied in the reduction of 4-nitrophenol by sodium borohydride, proving to be extraordinarily effective catalysts.

  15. Ligand-optimized electroless synthesis of silver nanotubes and their activity in the reduction of 4-nitrophenol

    Science.gov (United States)

    Muench, Falk; Rauber, Markus; Stegmann, Christian; Lauterbach, Stefan; Kunz, Ulrike; Kleebe, Hans-Joachim; Ensinger, Wolfgang

    2011-10-01

    A facile electroless plating procedure for the controlled synthesis of nanoscale silver thin films and derived structures such as silver nanotubes was developed and the products were characterized by SEM, TEM and EDS. The highly stable plating baths consist of AgNO3 as the metal source, a suitable ligand and tartrate as an environmentally benign reducing agent. Next to the variation of the coordinative environment of the oxidizing component, the influence of the pH value was evaluated. These two governing factors strongly affect the plating rate and the morphology of the developing silver nanoparticle films and can be used to adapt the reaction to synthetic demands. The refined electroless deposition allows the fabrication of homogeneous high aspect-ratio nanotubes in ion track etched polycarbonate. Template-embedded metal nanotubes can be interpreted as parallelled microreactors. Following this concept, both the silver nanotubes and spongy gold nanotubes obtained by the use of the silver structures as sacrificial templates were applied in the reduction of 4-nitrophenol by sodium borohydride, proving to be extraordinarily effective catalysts.

  16. Effect of Annealing Temperature on Hardness and Wear Resistance of Electroless Ni-B-Mo Coatings

    Science.gov (United States)

    Serin, Ihsan Gökhan; Göksenli, Ali

    2015-06-01

    Formation of nickel-boron-molybdenum (Ni-B-Mo) coating on steel by electroless plating and evaluation of their morphology, hardness and tribological properties post heat treatment at different temperatures for 1 h is investigated. The 25 μm thick coating is uniform and adhesion between the substrate and coating is good. Ni-B-Mo coating was amorphous-like structure in their as-plated condition and by 400°C heat-treated coating, nickel fully crystallized and nickel borides and molybdenum carbide were formed. All coatings exhibited higher hardness than the substrate steel. Hardness values of all coatings up to 400°C did not change distinctively but decreased partly beyond 400°C. Friction coefficient reached lowest value post heat treatment at 300°C but later increased with increasing tempering temperature. Wear resistance was lowest in as-plated coating; however it reached the highest value at 300°C. Worn surface of the coatings showed the abrasive wear as the dominant wear mechanism. An additional adhesive wear mechanism was detected in coating tempered at 550°C. Moreover, our results confirmed that the molybdenum addition improved the thermal stability of the resulting coating. Therefore, Ni-B-Mo coating has potential for application in precision mould, optical parts mould or bipolar plates, where thermal stability is essential.

  17. Mechanical and electrochemical properties of ultrasonic-assisted electroless deposition of Ni–B–TiO{sub 2} composite coatings

    Energy Technology Data Exchange (ETDEWEB)

    Niksefat, Vahid; Ghorbani, Mohammad, E-mail: ghorbani@sharif.edu

    2015-06-05

    Highlights: • Ni–B–TiO{sub 2} coatings developed by ultrasonic-assisted electroless method. • Titania improves corrosion resistance and hardness of the Ni–B as-plated coatings. • Titania increases the surface film resistance of the Ni–B as-plated coatings. - Abstract: Nickel–Boron–Titania (Ni–B–TiO{sub 2}) composite coatings were successfully obtained on mild steel (St-37) by simultaneous electroless deposition. TiO{sub 2} particles were dispersed in a suspension by ultrasonic irradiation. The surface morphology, particle size, elemental composition and phase analysis of the coatings were characterized by scanning electron microscopy (SEM), inductively coupled plasma (ICP) and X-ray diffraction (XRD). The hardness and friction coefficient of as- plated and heat treated Ni–B and Ni–B–TiO{sub 2} composite coatings were determined by Vickers diamond indentation and indentation scratch tests and compared with Ni–B coatings. As a result, the hardness (1263 HV) of the as-plated Ni–B–TiO{sub 2} coatings was improved significantly. In addition, the corrosion resistance behavior of the as-plated and heat treated Ni–B and Ni–B–TiO{sub 2} coatings were analyzed by anodic polarization and electrochemical impedance spectroscopic (EIS) studies in a 3.5 wt.% NaCl solution. The as-plated composite coatings (Ni–B–TiO{sub 2}) exhibited enhanced corrosion resistance (0.2 μA/cm{sup 2}) property over Ni–B coatings.

  18. Microwave absorption of electroless Ni-Co-P-coated SiO2 powder

    International Nuclear Information System (INIS)

    Ni-Co-P-coated SiO2 particles were prepared using electroless plating method. The morphology, crystal structure, surface compositions, magnetic and microwave absorption properties of the composite powder were investigated by scanning electron microscopy, X-ray diffraction analysis, X-ray photoelectron spectroscopy, vibrating sample magnetometer and vector network analyzer, respectively. It was found that the silica powder was successfully coated with Ni-Co-P alloy. The ultrafine Ni-Co-P-SiO2 powder-paraffin wax composite possesses excellent microwave absorption properties. The maximum microwave loss reaches -48.6 dB at 4.2 GHz with a thickness of 3.10 mm. The intrinsic reasons for microwave absorption were also investigated.

  19. Copper/bamboo fabric composite prepared via a silver catalytic electroless deposition process for electromagnetic shielding

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Qian; Lu, Yinxiang [Fudan Univ., Shanghai (China). Dept. of Materials Science

    2013-09-15

    Copper/bamboo fabric composite prepared via a silver catalytic electroless plating process is reported. The microstructure of the composite was analyzed by means of scanning electron microscopy, which illustrated that the copper coating was composed of spherical particles and clusters. The composition and chemical state of the metal layer were measured using X-ray diffraction and energy-dispersive X-ray analysis spectra; copper and a small amount of nickel were detected. Mechanical properties were measured based on a standard (ISO 13934-1:1999) for the fabrics with and without copper coating. The breaking force for the composite was improved by about 16.8% compared to uncoated bamboo fabric. The electromagnetic interference shielding effectiveness of the composite was more than 40 dB at frequencies ranging from 0.2 to 1000MHz. The copper coating on bamboo fabric passed the Scotch {sup registered} -tape test. (orig.)

  20. Process and properties of electroless Ni-W-B amorphous electrical resistance film

    Institute of Scientific and Technical Information of China (English)

    ZHU Xiao-yun; GUO Zhong-cheng; XU Rui-dong

    2004-01-01

    The process and properties of electroless plating Ni-W-B alloy have been studied. The results show that the deposits containing W and B are obtained, and the deposition rate of the bath is increased with increase of W content when a certain amount of sodium tungstate solution is added in the Ni-B bath. The Ni-W-B alloy is amorphous as deposition and its resistivity increases directly with the increase of W content in the coating, but decreases gradually with increasing the deposit thickness. XRD and SEM show that the distributions of W and B in the Ni-W-B alloy film are very uniform and dispersed without any segregation.

  1. Fabrication of Ni-P/palygorskite core-shell linear powder via electroless deposition

    Energy Technology Data Exchange (ETDEWEB)

    Zhou Sumin, E-mail: ccsm@hyit.edu.cn [College of Mechanical and Power Engineering, Nanjing University of technology, Nanjing 210009 (China); Key Laboratory for Palygorskite Science and Applied Technology of Jiangsu Province, Department of Chemical Engineering, Huaiyin Institute of Technology, Huaian 223003 (China); Wang Li [Key Laboratory for Palygorskite Science and Applied Technology of Jiangsu Province, Department of Chemical Engineering, Huaiyin Institute of Technology, Huaian 223003 (China); Shen Shiming [College of Mechanical and Power Engineering, Nanjing University of technology, Nanjing 210009 (China)

    2011-09-15

    Palygorskite is a kind of hydrated magnesium aluminium silicate clay mineral. A novel linear core-shell structured Ni-P coated micro-fiber palygorskite (MFP) was fabricated via an electroless (EL) plating process in an alkaline bath. The composition, morphology and structure of the as-prepared products were characterized by the techniques such as powder X-ray diffraction (XRD), energy-dispersive X-ray spectrum (EDS), scanning electron microscopy (SEM) and transmission electron microscope (TEM). It was observed that the size and morphology of Ni-P coated MFPs were altered by depositing temperature and time. The as-prepared Ni-P coated MFPs showed good conductivity. To the best of our knowledge, the Ni-P coated MFPs have not been reported before. And this fabrication process might also apply in preparing other metal coated MFPs such as silver, copper and palladium.

  2. Fabrication of Ni-P/palygorskite core-shell linear powder via electroless deposition

    Science.gov (United States)

    Zhou, Sumin; Wang, Li; Shen, Shiming

    2011-09-01

    Palygorskite is a kind of hydrated magnesium aluminium silicate clay mineral. A novel linear core-shell structured Ni-P coated micro-fiber palygorskite (MFP) was fabricated via an electroless (EL) plating process in an alkaline bath. The composition, morphology and structure of the as-prepared products were characterized by the techniques such as powder X-ray diffraction (XRD), energy-dispersive X-ray spectrum (EDS), scanning electron microscopy (SEM) and transmission electron microscope (TEM). It was observed that the size and morphology of Ni-P coated MFPs were altered by depositing temperature and time. The as-prepared Ni-P coated MFPs showed good conductivity. To the best of our knowledge, the Ni-P coated MFPs have not been reported before. And this fabrication process might also apply in preparing other metal coated MFPs such as silver, copper and palladium.

  3. Fabrication of Ni-P/palygorskite core-shell linear powder via electroless deposition

    International Nuclear Information System (INIS)

    Palygorskite is a kind of hydrated magnesium aluminium silicate clay mineral. A novel linear core-shell structured Ni-P coated micro-fiber palygorskite (MFP) was fabricated via an electroless (EL) plating process in an alkaline bath. The composition, morphology and structure of the as-prepared products were characterized by the techniques such as powder X-ray diffraction (XRD), energy-dispersive X-ray spectrum (EDS), scanning electron microscopy (SEM) and transmission electron microscope (TEM). It was observed that the size and morphology of Ni-P coated MFPs were altered by depositing temperature and time. The as-prepared Ni-P coated MFPs showed good conductivity. To the best of our knowledge, the Ni-P coated MFPs have not been reported before. And this fabrication process might also apply in preparing other metal coated MFPs such as silver, copper and palladium.

  4. Electromagnetic Interference Shielding Properties of Electroless Nickel-coated Carbon Fiber Paper Reinforced Epoxy Composites

    Institute of Scientific and Technical Information of China (English)

    CHEN Wei; WANG Jun; WANG Tao; WANG Junpeng; XU Renxin; YANG Xiaoli

    2014-01-01

    Carbon fibers (CFs) were coated with a nickel-phosphorus (Ni-P) film using an electroless plating process. The morphology, elemental composition and phases in the coating layer of the CFs were investigated by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD), respectively. Wet paper-making method was used to prepare nickle coated carbon fiber paper (NCFP). Vacuum assisted infusion molding process (VAIMP) was employed to manufacture the NCFP reinforced epoxy composites, and carbon fiber paper (CFP) reinforced epoxy composites were also produced as a comparison. Electromagnetic interference (EMI) shielding properties of the composites were measured in the 3.22-4.9 GHz frequency range using waveguide method. Both NCFP and CFP reinforced epoxy composites of 0.5 mm thickness exhibited high EMI shielding effectiveness (SE) at 8wt%fiber content, 35 dB and 30 dB, respectively, and reflection was the dominant shielding mechanism.

  5. Model of electroless Ni deposition on SiCp/Al composites and study of the interfacial interaction of coatings with substrate surface

    International Nuclear Information System (INIS)

    Metallization techniques based on electroless plating are used to coat SiCp/Al composite materials. The directly palladium chloride (PdCl2) solutions in HCl is used to render the surface of such non-conductive substrates catalytically active towards metal deposition in the electroless plating solution. The microstructures of Ni-coated composites provided by scanning electron microscope (SEM) bring light into the palladium activation and electroless coating process. Also, X-ray photoelectron spectroscopy (XPS) and Line-scan have allowed to monitor the chemical and compositional surface modifications of activated and coated SiCp/Al composites, as well as to understand the mechanisms of the catalyst (palladium species) chemisorption on the composites surface and the interaction mechanisms of Ni layer with the SiCp/Al composites. The experimental results show that a nickel-substrate bonding action takes place during plating. Ni atom existing on the surface of the composites can partially obtain electrons from metals Al of the SiCp/Al composites when the substrate is embedded in the Ni layers, that is, the orbital interaction through the mutual overlap of the electronic orbits does exist in the interfacial regions between the coated Ni atoms and composites substrate instead of the mechanical-interlocked form. On the basis of the evidence, a model of electroless Ni deposition on SiCp/Al composites is submitted including Pd activation and Ni deposition processes to describe the formation of catalytic centers and the growth of deposited layer. The deposition model reveals that metal-substrate bond plays an important role in the high adhesion strength between the Ni coatings and the composites

  6. Highly adhesive metal plating on Zylon ® fiber via iodine pretreatment

    Science.gov (United States)

    Fatema, Ummul Khair; Gotoh, Yasuo

    2011-11-01

    Highly adhesive metal plating was performed on poly(p-phenylene-2,6-benzobisoxazole) fiber named Zylon® via iodine pretreatment followed by electroless plating. First, iodine components were selectively doped into the inner part of the fiber near the surface through iodine vapor exposure. The doped iodine was converted to palladium iodide particles by treating with palladium chloride solution. After the reduction of the iodide to metal palladium particles, electroless copper plating was conducted on the fiber. A uniform copper layer was deposited on the fiber surface and exhibited high durability in durability tests such as ultrasonic exposure, tape peeling-off, and corrosion in NaCl solution. This durability was attributed to the palladium particles formed at the fiber surface that served as an anchor for the plated layer as well as an electroless plating catalyst. The plated fibers also possessed electrical conductivity. Although the tensile strength of the Zylon® fiber decreased from 5.8 to 4.9 GPa after undergoing the pretreatment and plating processes, the light shielding effect improved the light resistance of the plated fibers in terms of tensile properties. After 18 days of xenon lamp exposure, the plated fibers retained 74% of its initial strength, whereas that of untreated fibers decreased to 43%.

  7. Selective electroless copper deposition on self-assembled dithiol monolayers.

    Science.gov (United States)

    Aldakov, Dmitry; Bonnassieux, Yvan; Geffroy, Bernard; Palacin, Serge

    2009-03-01

    The paper reports the use of self-assembled monolayers (SAMs) of dithiols to induce electroless copper deposition on a gold substrate. The metallization catalyst, palladium nanoparticles, is bound on the dithiol SAM. The assembly process is followed by IR and X-ray photoelectron spectroscopies to confirm the formation of a monolayer with bound catalyst. Electroless metallization is then carried out with a steady deposition rate of 130 nm/min. Additionally, microcontact printing of the catalyst on the SAM by poly(dimethylsiloxane) stamps is used to localize copper deposits. Resulting metallization is selective and allows for a high resolution. PMID:20355979

  8. Optimizing growth conditions for electroless deposition of Au films on Si(111) substrates

    Indian Academy of Sciences (India)

    Bhuvana; G U Kulkarni

    2006-10-01

    Electroless deposition of Au films on Si(111) substrates from fluorinated-aurate plating solutions has been carried out at varying concentrations, deposition durations as well as bath temperatures, and the resulting films were characterized by X-ray diffraction, optical profilometry, atomic force microscopy and scanning electron microscopy. Depositions carried out with dilute plating solutions (< 0.1 mM) at 28°C for 30 min produce epitaxial films exhibiting a prominent Au(111) peak in the diffraction patterns, while higher concentrations or temperatures, or longer durations yield polycrystalline films. In both epitaxial and polycrystalline growth regimes, the film thickness increases linearly with time, however, in the latter case, at a rate an order of magnitude higher. Interestingly, the surface roughness measured using atomic force microscopy shows a similar trend. On subjecting to annealing at 250°C, the roughness of the film decreases gradually. Addition of poly (vinylpyrrolidone) to the plating solution is shown to produce a X-ray amorphous film with nanoparticulates capped with the polymer as evidenced by the core-level photoelectron spectrum. Nanoindentation using AFM has shown the hardness of the films to be much higher (∼ 2.19 GPa) than the bulk value.

  9. Effect of Annealing Temperature on the Corrosion Resistance of Electroless Ni-B-Mo Coatings

    Science.gov (United States)

    Serin, Ihsan Gökhan; Göksenli, Ali; Yüksel, Behiye; Yildiz, Rasid Ahmed

    2015-08-01

    The Ni-B-Mo coating on steel by electroless plating and the evaluation of the morphology and corrosion performance after applying heat treatments at different temperatures for 1 h were investigated in this study. The 25-μm-thick coating was uniform and adhesion between the substrate and the coating was good. The coating consisted of an amorphous-like structure in their as-plated condition, and after annealing at 400 °C for 1 h, crystallized nickel, nickel borides, and molybdenum carbide were formed. Immersion tests in 10% HCl solution and potentiodynamic polarization measurements in 3.5% NaCl aqueous solution were applied to investigate corrosion resistance. The corrosion performance of heat-treated coatings was compared with steel and the as-plated coating. By increasing the annealing temperature, corrosion potential shifted toward a noble direction, corrosion current density decreased and the weight loss of specimens decreased, demonstrating an increase in corrosion resistance. Best corrosion performance was achieved by the coating heat treated at 550 °C.

  10. Deposition and characterization of amorphous electroless Ni-Co-P alloy thin film for ULSI application

    International Nuclear Information System (INIS)

    Electroless based Ni-Co-P alloy thin films were deposited using sodium hypophosphite as a reducing agent and sodium citrate as a complexing agent in an alkaline plating bath. The effect of solution pH and temperature on the plating rate was examined. The decrease in activation energy (81.35 − 73.54 kJ mole−1) for the Ni-Co-P thin films deposited on corning glass was observed with the increase in pH (8.5–9.38) of the plating bath. There is a significant decrease in sheet resistance of alloy thin films as the post deposition annealing temperature approaches 400 °C. The presence of nickel as well as nickel phosphide peaks and transition from metastable Ni12P5, Ni8P5 and Ni5P2 phases into thermodynamically stable NiP, NiP2, Ni3P phases after annealing at 600 °C was observed in XRD spectra, indicating the crystallization of the thin films. Surface topography analysis shows the variation of grain size in the range 20–40 nm. (paper)

  11. Determination of electroless deposition by chemical nickeling

    Directory of Open Access Journals (Sweden)

    M. Badida

    2013-07-01

    Full Text Available Increasing of technical level and reliability of machine products in compliance with the economical and ecological terms belongs to the main trends of the industrial development. During the utilisation of these products there arise their each other contacts and the interaction with the environment. That is the reason for their surface degradation by wear effect, corrosion and other influences. The chemical nickel-plating allows autocatalytic deposition of nickel from water solutions in the form of coherent, technically very profitable coating without usage of external source of electric current. The research was aimed at evaluating the surface changes after chemical nickel-plating at various changes of technological parameters.

  12. Effectiveness of nickel plating in inhibiting atmospheric corrosion of copper alloy contacts

    Energy Technology Data Exchange (ETDEWEB)

    Ernest, T.; Sorensen, R.; Guilinger, T.

    1997-12-31

    A series of tests was run to determine the effect of Ni plating thickness on connector contact resistance. Copper coupons were plated with an electrolytic nickel strike followed by electroless nickel to produce Ni layers of 10, 20, 55 and 100 {micro}in. The coupons were then exposed to a simulated industrial environment. Pore corrosion was observed after the exposure, which correlated with Ni thickness. In a second series of tests, beryllium-copper four-tine contacts with 50 {micro}in of gold plate over electrolytic nickel strike/electroless-nickel plates of varying thickness were exposed the same corrosive environment. Contact resistance of mated pairs was monitored over a two-month period. The degradation in contact resistance correlated with the Ni thickness used in the connectors.

  13. Microwave absorbing properties of hollow microspheres plated with magnetic metal films

    Science.gov (United States)

    Kim, Sun-Tae; Kim, Sung-Soo

    2014-05-01

    Conductive and magnetic microspheres are fabricated through the electroless plating of Co, Co-10%Fe, Ni, and Ni-15%Fe films on hollow microspheres (cenospheres), and their high frequency electromagnetic and microwave absorbing properties are investigated in the composite specimens. The electroless plating of the metal films is conducted using a two-step process of surface sensitizing and metal plating. For the microspheres coated with the Co and Co-10%Fe films, impedance matching is not satisfied at all frequencies due to the small values of magnetic loss and dielectric constant. For the Ni-plated microsphere composites, the dielectric constant is too high to satisfy the impedance matching, which results in a small value of microwave absorbance. For the Ni-15%Fe thin film composite with appropriate magnetic permeability and dielectric permittivity, the impedance matching is satisfied in the GHz frequency and a lower value of reflection loss is predicted.

  14. An Electrochemical Investigation of Electroless Deposition: the Copper-DMAB System

    OpenAIRE

    Plana, Daniela

    2010-01-01

    An electrochemical study of the copper electroless deposition process, using dimethylamine borane as a reducing agent, has been performed, in order to gain further understanding of the mechanism and kinetics of electroless deposition. An in-depth study of the electro-oxidation of dimethylamine borane (DMAB) was additionally carried out, due to its increasing relevance, not only in electroless deposition, but also in fuel cell technology.DMAB oxidation was studied using different experimental ...

  15. Determination of electroless deposition by chemical nickeling

    OpenAIRE

    Badida, M.; M. Gombár; L. Sobotová; J. Kmec

    2013-01-01

    Increasing of technical level and reliability of machine products in compliance with the economical and ecological terms belongs to the main trends of the industrial development. During the utilisation of these products there arise their each other contacts and the interaction with the environment. That is the reason for their surface degradation by wear effect, corrosion and other influences. The chemical nickel-plating allows autocatalytic deposition of nickel from water solutions in the fo...

  16. Characterization of PdAg/Al2O3 composite membrane by electroless co-deposition

    International Nuclear Information System (INIS)

    In this work, PdAg/Al2O3 composite membranes prepared by electroless co-deposition technique have been studied. Effects of plating time, Ag composition and total concentration of metal ions on surface morphologies, composition and microstructure of the resulting layers were investigated. Scanning electron microscope, energy dispersive spectrometer and nitrogen permeation technique were used to characterize the as-prepared composite membranes. From the experimental results, it shows that the surface morphology of the deposited PdAg layer is strongly affected by the Ag content of the plating bath. Since large differences of deposition rates and growth modes are observed between Pd and Ag grains, the PdAg layer exhibits the dendritic structure. As the Ag content is approximately 50%, the dendritic structured PdAg layer reveals the largest nitrogen permeability with the smallest size of residual pores. Furthermore, a comprehensive electrochemical analysis is proposed to interpret the composition and structure of the PdAg layer. Eventually, the experimental results are quite consistent with those predicted from the electrochemical analysis

  17. Preparation and characterization of electroless Ni–B/nano-SiO2, Al2O3, TiO2 and CuO composite coatings

    Indian Academy of Sciences (India)

    Dursun Ekmekci̇; Ferhat Bülbül

    2015-06-01

    Ni–B/SiO2, Al2O3, TiO2 and CuO composite coatings were successfully obtained by the electroless plating technique. Dispersible SiO2, Al2O3, TiO2 and CuO nanoparticles were co-deposited with electroless Ni–B coating onto AISI-304 steel substrates. Deposits were characterized for its structural properties by X-ray diffraction (XRD). XRD results showed a broad peak of Ni–B and low intensity composite nanoparticle peaks. The surface and cross-section morphology of samples were analysed using a scanning electron microscope (SEM). Surface analysis showed that the incorporation in Ni–B matrix of nano-SiO2, Al2O3, TiO2 and CuO particles increases the nodularity of composite coatings. The deposits are composed of a columnar structure grown along the vertical direction of the substrate surface. The results also show that electroless nanocomposite coatings tend to have greater microhardness compared with the coating without nanoparticles. The increase in the microhardness of the nanocomposite coatings reported in this study is attributed to an effect of dispersion strengthening of ceramic particles in the Ni–B matrix.

  18. Electroless Deposition of Ni-Cu-P Coatings Containing Nano-Al2O3 Particles and Study of Its Corrosion Protective Behaviour in 0.5 M H2SO4

    OpenAIRE

    H. Ashassi-Sorkhabi; Aminikia, H.; R. Bagheri

    2014-01-01

    Ni-Cu-P/nano-Al2O3 composite coatings are prepared on mild steel from an alkaline electroless plating bath containing different concentrations of Al2O3 nanoparticles. The protective effect of codeposited nanoparticles on the corrosion behaviour of the coatings is studied in 0.5 M H2SO4 solution. The electrochemical methods, that is, electrochemical noise (ECN), electrochemical impedance spectroscopy (EIS), and polarization measurements, are used to characterize the corrosion properties of the...

  19. Effect of rare element cerium on the morphology and corrosion resistance of electro-less Ni-P coatings

    Directory of Open Access Journals (Sweden)

    Fu Chuan-qi

    2015-01-01

    Full Text Available This paper reports an experimental study on the microstructure and corrosion resistance of electro-less Ni-P coatings with increasing content of the rare element cerium (Ce. Surface morphology and the composition of the electro-less Ni-P coatings were studied by scanning electron microscope (SEM, X-ray energy dispersed analysis (EDS and X-ray diffraction analysis (XRD. Hardness and Adhesive force are researched by a HX-200 Vickers diamond indenter micro-hardness tester. Furthermore, we study the adhesive force by using the Revetest scratch tester. We get the possession of Ce amorphous Ni-P coatings which has excellent properties in anti-corrosion. The effect of the rare element cerium concentration on corrosion resistance of the coatings was evaluated in the groundwater immersion test and porosity test, respectively. The results indicated that added little the rare element cerium into the plating bath increased the phosphorus content of the coatings, decreased the corrosion rates, it also decreases the porosity of the amorphous Ni-P coatings. The lowest corrosion rates of the amorphous Ni-P coatings in groundwater immersion test is 4.1 um · h-1, at the rare element cerium concentration of 0.12g · L-1.

  20. Electroless deposition of conducting polymers using the scanning electrochemical microscope

    Energy Technology Data Exchange (ETDEWEB)

    Borgwarth, K.; Ricken, C.; Heinze, J. [Freiburg Univ. (Germany). Inst. fuer Physikalische Chemie; Rohde, N.; Hallensleben, M.L.; Mandler, D.

    1999-10-01

    Micropatterning of organic substances using scanning electrochemical microscopy (SECM) is presented as a versatile, reproducible method for obtaining patterned materials of mesoscopic resolution-between that of conventional lithography and scanning tunneling microscopy or atomic force microscopy. In this technique, conducting polymer is electrolessly deposited on different substrates. It is reported that both flat layers and sets of thin needles protruding from the surface may be formed simply by varying the nature of the redox mediator. (orig.)

  1. Electroless nickel, alloy, composite and nano coatings - A critical review

    OpenAIRE

    Sudagar, Jothi; Lian, Jianshe; Sha, Wei

    2013-01-01

    The development of metal deposition processes based on electroless nickel, alloy and composite coatings on various surfaces has witnessed a surge in interest among researchers, with many recent applications made possible from many excellent properties. In recent years, these coatings have shown promising corrosion and wear resistance properties and large number of newer developments became most important from macro to nano level applications. After a brief review of the fundamental aspects un...

  2. Potentiodynamic Polarization Behaviour of Electroless Ni-P-W Coatings

    OpenAIRE

    Supriyo Roy; Prasanta Sahoo

    2012-01-01

    This paper deals with the synthesis of electroless Ni-P-W coatings on mild steel substrate followed by furnace-annealing process. Corrosion behaviors of the coatings after heat treatments at various annealing temperatures are evaluated by potentiodynamic polarization test using 3.5% sodium chloride solution. The electrochemical parameters, that is, corrosion potential and corrosion current density, are optimized for maximum corrosion resistance using Taguchi-based grey relational analysis, co...

  3. Enhancement of porous silicon photoluminescence by electroless deposition of nickel

    International Nuclear Information System (INIS)

    Nickel-porous silicon nanocomposites (PS/Ni) are elaborated by an electroless deposition method using NiCl2 aqueous solution. The presence of nickel ions in the porous layer is confirmed by Fourier Transformed InfraRed spectroscopy (FTIR) and Raman spectroscopy. The photoluminescence (PL) spectra of PS/Ni, prepared at different electroless durations (tedp), are analyzed. A remarkable enhancement in the integrated PL intensity of PS containing nickel was observed. The lower tedp favor the deposition of nickel in PS, hence the silicon dangling bonds at the porous surface are quenched and this was increased the PL intensity. However, for the longer tedp, the PL intensity has been considerably decreased due to the destruction of some Si nanocrystallites. The PL spectra of PS/Ni, for tedp less than 8 min, show a multiband profile indicating the creation of new luminescent centers by Ni elements which induces a strong modification in the emission mechanisms. - Highlights: • Deposition of Ni ions into porous silicon (PS) layer using the electroless method. • Formation of Ni–O bonds on the porous layer. • The photoluminescence (PL) intensity of PS is enhanced after Ni deposition. • The increase of the PL is due to the contribution of radiative centers related to Ni

  4. Phase composition, microstructure and microhardness of electroless nickel composite coating co-deposited with SiC on cast aluminium LM24 alloy substrate

    OpenAIRE

    Franco, M.; Sha, W.; Malinov, S.; Rajendran, R

    2013-01-01

    Electroless Ni–P (EN) and composite Ni–P–SiC (ENC) coatings were developed on cast aluminium alloy substrate, LM24. The coating phase composition, microstructure and microhardness were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM) and microhardness tester, respectively, on as-plated and heat-treated specimens. The original microstructure of the Ni–P matrix is not affected by the inclusion of the hard particles SiC. No formation of Ni–Si phase was observed up t...

  5. Characterisation of phase composition, microstructure and microhardness of electroless nickel composite coating co-deposited with SiC on casting aluminium LM24 alloy substrate

    OpenAIRE

    Franco, M.; Sha, Wei; Malinov, Savko

    2013-01-01

    Electroless Ni-P (EN) and composite Ni-P-SiC (ENC) coatings were developed on cast aluminium alloy, LM24. The coating phase composition, microstructure and microhardness were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM) and microhardness tester, respectively, on as-plated and heat-treated specimens. The original microstructure of the Ni-P matrix is not affected by the inclusion of the hard particles SiC. No formation of Ni-Si phase was observed upto 500°C of ...

  6. Effect of pickling processes on the microstructure and properties of electroless Ni–P coating on Mg–7.5Li–2Zn–1Y alloy

    OpenAIRE

    Chunjie Xu; Liping Chen; Ling Yu; Jinxiao Zhang; Zhongming Zhang; Jincheng Wang

    2014-01-01

    The electroless plating Ni–P is prepared on the surface of Mg–7.5Li–2Zn–1Y alloys with different pickling processes. The microstructure and properties of Ni–P coating are investigated. The results show that the Ni–P coatings deposited using the different pickling processes have a different high phosphorus content amorphous Ni–P solid solution structure, and the Ni–P coatings exhibit higher hardness. There is higher phosphorus content of Ni–P amorphous coating using 125 g/L CrO3 and 110 ml/L H...

  7. In-depth survey report of American Airlines plating facility

    Science.gov (United States)

    Mortimer, V. D., Jr.

    1982-12-01

    An in depth survey was conducted at the American Airlines Maintenance and Engineering Center as part of National Institute for Occupational Safety and Health (NIOSH) study evaluating measures to control occupational health hazards associated with the metal plating industry. This American Airlines plating facility, employing approximately 25 workers, is primarily engaged in plating hard chromium, nickel and cadmium on aircraft engine and landing gear parts. Six tanks were studied, including an electroless nickel tank. Area and personal samples for chromium, nickel, cadmium, and cyanide were collected. Ventilation airflow and tank dimensions were measured and data recorded on plating operations. The relationships between air contaminants emitted, local exhaust ventilation flow rate, tank size, and plating activity were evaluated.

  8. Electroless deposition of palladium. Pt. 2; Stromlose Abscheidung von Palladium. T. 2

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Terence

    2013-04-15

    In Part 1 of this series on the electroless deposition of palladium, the properties of the metal itself were discussed as well as the benefits of the electroless deposition process. In Part 2, the autocatalytic position processes are detailed with an exhaustive review of previously published work in this area. (orig.)

  9. Electroless deposition of Ni-P-nano-ZrO2 composite coatings in the presence of various types of surfactants.

    Science.gov (United States)

    Zielińska, Katarzyna; Stankiewicz, Alicja; Szczygieł, Irena

    2012-07-01

    Ni-P-nano-ZrO(2) coatings were produced using the electroless deposition technique. To prevent agglomeration of zirconia nanoparticles in the plating bath, various surfactant additives (anionic, cationic, and nonionic) were used. The most stable bath was obtained with the addition of dodecyltrimethylammonium bromide (DTAB). The impact of this surfactant on the deposition rate, coating composition, and topography, as well as ζ potential of particles, was examined. Surface morphology and composition of the Ni-P-nano-ZrO(2) composite coatings was analyzed by various techniques including scanning electron microscopy (SEM) equipped with in situ energy-dispersive X-ray (EDX) spectroscopy. Coatings with a clearly greater amount of zirconia (21.88-22.10 wt.%) were obtained from baths containing DTAB in concentrations equal to or above its critical micelle concentration (cmc). For these surfactant concentrations, the reduction of Ni and P content was observed. PMID:22498365

  10. Corrosion Resistance of Electroless Ni-Cu-P Ternary Alloy Coatings in Acidic and Neutral Corrosive Mediums

    Directory of Open Access Journals (Sweden)

    Mbouillé Cissé

    2010-01-01

    Full Text Available Electroless Ni-Cu-P alloy coatings were deposited on the ordinary steel substrate in an acidic hypophosphite-type plating bath. These coatings were characterized by a scanning electron microscope (SEM and an X-ray diffraction. The micrograph shows that coating presents a nodular aspect and is relatively homogeneous and very smooth. The EDX analysis shows that the coating contains 12 wt.% of phosphorus element with a predominance of nickel element. In addition, the anticorrosion properties of the Ni-Cu-P coatings in 1 M HCl, 1 M H2SO4, and 3% NaCl solutions were investigated using Tafel polarization curves, electrochemical impedance spectroscopy, and SEM/EDX analysis. The result showed a marginal improvement in corrosion resistance in 3% NaCl solution compared to acidic medium. It also showed that the corrosion mechanism depends on the nature of the solution.

  11. Tribological properties of electroless Ni-P-SiC composite coatings in rolling/sliding contact under boundary lubrication

    Institute of Scientific and Technical Information of China (English)

    Wei-Long Liu; Shu-Hue Hsieh; Shen-Jenn Hwang; Ting-Kan Tsai; Wen-Jauh Chen

    2007-01-01

    Ni-P-SiC composite coatings were prepared under a given bath composition and operation parameters of electroless plating. The tribological properties of the Ni-P-SiC composite coatings after annealing at 400°C for 1 h were tested in rolling/sliding contact under boundary lubrication condition using a two-roller tribometer. The measurement contained friction coefficient, contact surface temperature, contact electrical resistance, and wear rate of the Ni-P-SiC composite coatings under various slide to roll ratios, loads, and rolling speeds. For the simultaneous examination of the effect of the chosen parameters on the tribological properties of the Ni-P-SiC composite coatings, an orthogonal regression experimental design method was used.

  12. Microstructure and corrosion behavior of electroless deposited Ni-P/CeO2 coating

    Institute of Scientific and Technical Information of China (English)

    Hui Ming Jin; Shi Hang Jiang; Lin Nan Zhang

    2008-01-01

    Electroless Ni-P/nano-CeO2 composite coating was prepared in acidic condition,and its microstructure and corrosive property were compared with its CeO2-free counterpart.Scanning electronic microscopy (SEM) and X-ray diffraction (XRD) spectrometer were used to examine surface morphology and structure of the as-plated coating.Differential scanning calorimeter (DSC) and transmission electronic microscopy (TEM) were used to study the coating's phase change at high temperature.The coating's corrosive behavior in 3%NaCI + 5%H2SO4 solution was also investigated.The results showed that Ni-P coating had partial amorphous structure mixed with nano-crystals,while the Ni-P/CeO2 coating had perfect amorphous structure.In high-temperature condition,Ni3P precipitation and Ni crystallization took place in both coatings but at different temperatures,while the Ni-P/CeO2 coating had sintered phase of NiCe2O4 spinels.The anti-corrosion property was better in the CeO2-containing coating,and this was due to its less liability to undergo local-cell corrosion than its CeO2-free counterpart.Ni-P/CeO2 coating's pure amorphous structure was the result of Ni's hindered crystal-typed deposition and P's promoted deposition.

  13. Polystyrene as a zwitter resist in electron beam lithography based electroless patterning of gold

    Indian Academy of Sciences (India)

    T Bhuvana; G U Kulkarni

    2008-06-01

    The resist action of polystyrene (w, 2,600,000) towards electroless deposition of gold on Si(100) surface following cross-linking by exposing to a 10 kV electron beam, has been investigated employing a scanning electron microscope equipped with electron beam lithography tool. With a low dose of electrons (21 C/cm2), the exposed regions inhibited the metal deposition from the plating solution due to cross-linking—typical of the negative resist behaviour of polystyrene, with metal depositing only on the developed Si surface. Upon increased electron dosage (160 C/cm2), however, Au deposition took place even in the exposed regions of the resist, thus turning it into a positive resist. Raman measurement revealed amorphous carbon present in the exposed region that promotes metal deposition. Further increase in dosage led successively to negative (220 C/cm2) and positive (13,500 C/cm2) resist states. The zwitter action of polystyrene resist has been exploited to create line gratings with pitch as low as 200 nm and gap electrodes down to 80 nm.

  14. Stability of nonfouling electroless nickel-polytetrafluoroethylene coatings after exposure to commercial dairy equipment sanitizers.

    Science.gov (United States)

    Huang, Kang; Goddard, Julie M

    2015-09-01

    Application of nonfouling coatings on thermal processing equipment can improve operational efficiency. However, to enable effective commercial translation, a need exists for more comprehensive studies on the stability of nonfouling coatings after exposure to different sanitizers. In the current study, the influence of different commercial dairy equipment sanitizers on the nonfouling properties of stainless steel modified with electroless Ni-polytetrafluoroethylene (PTFE) coatings was determined. Surface properties, such as dynamic contact angle, surface energy, surface morphology, and elemental composition, were measured before and after the coupons were exposed to the sanitizers for 168 cleaning cycles. The fouling behavior of Ni-PTFE-modified stainless steel coupons after exposure was also evaluated by processing raw milk on a self-fabricated benchtop-scale plate heat exchanger. The results indicated that peroxide sanitizer had only minor effect on the Ni-PTFE-modified stainless steel surface, whereas chlorine- and iodine-based sanitizers influenced the surface properties drastically. The coupons after 168 cycles of exposure to peroxide sanitizer accumulated the least amount of fouling material (4.44±0.24mg/cm(2)) compared with the coupons exposed to the other 3 sanitizers. These observations indicated that the Ni-PTFE nonfouling coating retained antifouling properties after 168 cycles of exposure to peroxide-based sanitizer, supporting their potential application as nonfouling coatings for stainless steel dairy processing equipment. PMID:26142857

  15. Effects of Two Purification Pretreatments on Electroless Copper Coating over Single-Walled Carbon Nanotubes

    Directory of Open Access Journals (Sweden)

    Zhong Zheng

    2014-01-01

    Full Text Available To achieve the reinforcement of copper matrix composite by single-walled carbon nanotubes, a three-step-refluxing purification of carbon nanotubes sample with HNO3-NaOH-HCl was proposed and demonstrated. A previously reported purification process using an electromagnetic stirring with H2O2/HCl mixture was also repeated. Then, the purified carbon nanotubes were coated with copper by the same electroless plating process. At the end, the effects of the method on carbon nanotubes themselves and on copper coating were determined by transmission electron microscope spectroscopy, scanning electron microscope spectroscopy, X-ray diffractometry, thermogravimetric analysis, Fourier transformed infrared spectroscopy, and energy dispersive spectrometry. It was clearly confirmed that both of the two processes could remove most of iron catalyst particles and carbonaceous impurities without significant damage to carbon nanotubes. The thermal stability of the sample purified by H2O2/HCl treatment was slightly higher than that purified by HNO3-NaOH-HCl treatment. Nevertheless, the purification by HNO3-NaOH-HCl treatment was more effective for carboxyl functionalization on nanotubes than that by H2O2/HCl treatment. The Cu-coating on carbon nanotubes purified by both purification processes was complete, homogenous, and continuous. However, the Cu-coating on carbon nanotubes purified by H2O2/HCl was oxidized more seriously than those on carbon nanotubes purified by HNO3-NaOH-HCl treatment.

  16. Novel electroless gold nano-architectures to enhance photon-plasmon coupling

    Science.gov (United States)

    Ahn, Wonmi

    Understanding and enhancing electromagnetic (EM) coupling in noble metal nano-structures is important in opto-electronics, bio-photonics, and spectroscopic sensors. In this study, light-to-heat transduction in novel gold (Au) nanoparticle (NP) architectures is quantitatively determined for the first time by applying a linearized energy balance. In particular, dense solid-state Au NP arrays coated on internal walls of silica capillaries using a 'bottom-up' electroless (EL) plating method dissipate >10-fold more heat from incident photons (96.9 vs. 9.9%) with a >10-fold faster heat transfer response time (8.4 vs. 86.3 s) by preventing aggregation between NPs that typically occurs in colloidal Au NP suspensions when irradiated with light. These photothermally-stable solid-state Au nano-architectures are created using an inexpensive EL plating process by reduction of Au ions on tin-sensitized and silver-activated silica surfaces at ambient conditions without requiring conductive substrates or expensive, sophisticated top-down metal deposition equipment. Heat-induced changes in morphology from Au island thin films to random arrays of spherical Au NPs result in tunable optical properties such as photoluminescence (PL) and LSPR. Especially, the ability to tune the LSPR properties by varying NP size and inter-particle spacing is a key factor in improving and optimizing plasmonic devices. Finally, to control NP size and inter-particle spacing, the application of bottom-up EL plating is expanded herein to create regular arrays of Au nanospheres on silica surfaces patterned by (i) electron beam lithography (EBL), and (ii) nanosphere lithography (NSL). Regular arrays of Au nanospheres created by successive thermal treatments of EBL-patterned EL Au island films exhibit dramatically improved NP sphericity, when compared to NP arrays prepared using top-down Au sputtering. Moreover, selective EL plating on the NSL-patterned silane masks produces multiple samples of regular NP

  17. Electroless silver as an optical coating in an operational environment.

    Science.gov (United States)

    Nahrstedt, D; Glesne, T; McNally, J; Kenemuth, J; Magrath, B

    1996-07-01

    Long-term, independent experiments show a high degradation rate and short lifetime for electroless silver as a mirror coating operating at visible wavelengths in an observatory environment. Acid formed by water vapor mixing with sulfur in volcanic dust diffuses through pinholes in the coating generated during deposition. This causes internal corrosion and delamination after only 3-4 months. In addition, a layer of silver sulfide results in tarnish, which reduces reflectance. Rates of sulfidation and internal corrosion are shown to depend on the concentration of sulfur and the exposure rate. Comparisons of performance, lifetime, and the application process are made with bare aluminum and two variations of enhanced silver. PMID:21102764

  18. Preparation, characterization and microwave absorption properties of electroless Ni-Co-P-coated SiC powder

    International Nuclear Information System (INIS)

    Silicon carbide particles reinforced nickel-cobalt-phosphorus matrix composite coatings were prepared by two-step electroless plating process (pre-treatment of sensitizing and subsequent plating) for the application to lightweight microwave absorbers, which were characterized by scanning electron microscopy (SEM), X-ray diffraction analysis (XRD), vibrating sample magnetometer (VSM) and vector network analyzer, respectively. The results show that Ni-Co-P deposits are uniform and mixture crystalline of α-Co and Ni3P and exhibit low-specific saturation magnetization and low coercivity. Due to the conductive and ferromagnetic behavior of the Ni-Co thin films, high dielectric constant and magnetic loss can be obtained in the microwave frequencies. The maximum microwave loss of the composite powder less than -32 dB was found at the frequency of 6.30 GHz with a thickness of 2.5 mm when the initial atomic ratio of Ni-Co in the plating bath is 1.5

  19. Preparation, characterization and microwave absorption properties of electroless Ni Co P-coated SiC powder

    Science.gov (United States)

    Li, Yongjie; Wang, Rui; Qi, Fengming; Wang, Chunming

    2008-05-01

    Silicon carbide particles reinforced nickel-cobalt-phosphorus matrix composite coatings were prepared by two-step electroless plating process (pre-treatment of sensitizing and subsequent plating) for the application to lightweight microwave absorbers, which were characterized by scanning electron microscopy (SEM), X-ray diffraction analysis (XRD), vibrating sample magnetometer (VSM) and vector network analyzer, respectively. The results show that Ni-Co-P deposits are uniform and mixture crystalline of α-Co and Ni 3P and exhibit low-specific saturation magnetization and low coercivity. Due to the conductive and ferromagnetic behavior of the Ni-Co thin films, high dielectric constant and magnetic loss can be obtained in the microwave frequencies. The maximum microwave loss of the composite powder less than -32 dB was found at the frequency of 6.30 GHz with a thickness of 2.5 mm when the initial atomic ratio of Ni-Co in the plating bath is 1.5.

  20. Effects of Properties on S45C Carbon Steel by Electroless NiP Adding Al2O3 Powder of Composite Deposition and Various Heat Treatments

    International Nuclear Information System (INIS)

    This research studies the effects on the surface microstructure and mechanical properties of S45C carbon steel via electroless Ni-P, by adding αAl2O3 powder via composite deposition and various heat treatments. The plating specimens were treated with pH5 and pH8 baths heated to 350°C and 300°C, respectively, and soaked for 1 hr. Meanwhile, two different particle sizes of Al2O3 powder were added to the electroless Ni-P plating: 0.3 μm of αAl2O3 and 0.05 μm of γAl2O3 powder, respectively. The experimental results show that, after 1 hr of heat treatment at 300°C, the optimal hardness for the specimens using the pH8 of Ni-P with αAl2O3 and γAl2O3 added by composite deposition are HV0.05 1237 and HV0.05 1145, respectively. All of the specimens underwent the main precipitate phase of Ni3P after heat treatment

  1. Electroless silver coating of rod-like glass particles

    International Nuclear Information System (INIS)

    An electroless silver coating of rod-like glass particles was performed and silver glass composite powders were prepared to impart electrical conductivity to these non-conducting glass particles. The low density Ag-coated glass particles may be utilized for manufacturing conducting inorganic materials for electromagnetic interference (EMI) shielding applications and the techniques for controlling the uniform thickness of silver coating can be employed in preparation of biosensor materials. For the surface pretreatment, Sn sensitization was performed and the coating powders were characterized by scanning electron microscopy (SEM), focused ion beam microscopy (FIB), and atomic force microscopy (AFM) along with the surface resistant measurements. In particular, the use of FIB technique for determining directly the Ag-coating thickness was very effective on obtaining the optimum conditions for coating. The surface sensitization and initial silver loading for electroless silver coating could be found and the uniform and smooth silver-coated layer with thickness of 46 nm was prepared at 2 mol/l of Sn and 20% silver loading

  2. Parametric optimization and prediction of electroless Ni-B deposition

    International Nuclear Information System (INIS)

    The alkaline borohydride-reduced bath has been used to deposit electroless nickel-boron (Ni-B) coatings on a pure (99.99%) copper substrate. The electroless Ni-B deposition per unit area has been considered as a response variable and response surface method has been used to optimize the process parameters and the response. Initially, a first order response surface model has been considered and steepest ascent method has been used to reach in the vicinity of optimal region of the response surface and subsequently, a second order response surface model with central composite design (CCD) has been used to take into account the curvature around the optimal region. The predicting response surface equation has been determined by using MATLAB software package and the optimal values of process parameters have been determined for maximum deposition per unit area. The three-dimensional surface and contour plots shows the variation Ni-B deposition with different process parameters. F-test for the predicting response surface equation confirms that the equation gives an excellent fitting to the experimentally observed data

  3. Electroless silver coating of rod-like glass particles.

    Science.gov (United States)

    Moon, Jee Hyun; Kim, Kyung Hwan; Choi, Hyung Wook; Lee, Sang Wha; Park, Sang Joon

    2008-09-01

    An electroless silver coating of rod-like glass particles was performed and silver glass composite powders were prepared to impart electrical conductivity to these non-conducting glass particles. The low density Ag-coated glass particles may be utilized for manufacturing conducting inorganic materials for electromagnetic interference (EMI) shielding applications and the techniques for controlling the uniform thickness of silver coating can be employed in preparation of biosensor materials. For the surface pretreatment, Sn sensitization was performed and the coating powders were characterized by scanning electron microscopy (SEM), focused ion beam microscopy (FIB), and atomic force microscopy (AFM) along with the surface resistant measurements. In particular, the use of FIB technique for determining directly the Ag-coating thickness was very effective on obtaining the optimum conditions for coating. The surface sensitization and initial silver loading for electroless silver coating could be found and the uniform and smooth silver-coated layer with thickness of 46 nm was prepared at 2 mol/l of Sn and 20% silver loading. PMID:18571859

  4. A novel preparation of silver-plated polyacrylonitrile fibers functionalized with antibacterial and electromagnetic shielding properties

    International Nuclear Information System (INIS)

    Highlights: • We propose a novel modification method to initiate silver electroless plating on PAN fiber without noble metal catalyst. • The silver-plated fiber we fabricated has good electromagnetic shielding effectiveness and antibacterial properties. • The metal layer has good adhesion strength and the properties of the silver-plated fiber can stand 30 cycles of standard washing. - Abstract: Polyacrylonitrile (PAN) fibers with antibacterial, electromagnetic shielding and antistatic functionalities were fabricated in this paper through modifying PAN fibers with (3-aminopropyl)triethoxysilane (APTES) and 3-mercaptopropyltriethoxysilane (MPTES) sequentially and followed with silver electroless plating. The silver layer on PAN fiber surface was characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM) and X-ray diffraction (XRD). The results show that the silver layer was plated uniformly and compactly. The surface resistance of plated fabric was about 40 mΩ/sq on average. The antibacterial tests demonstrate that silver-plated PAN fiber exhibits excellent antibacterial property against S. aureus and E. coli with a non-leaching characteristic. The antibacterial property remains good after 30 cycles of standard washing, which is a strong proof of a durable adhesion between metal layer and fiber. The shielding effectiveness (SE) of silver-plated PAN fabric before and after 30 cycles of standard washing was about 40–80 dB and 35–50 dB, respectively. This resultant fiber can be used in many occasions for reducing or preventing electromagnetic interference (EMI) and electromagnetic hazards

  5. A novel preparation of silver-plated polyacrylonitrile fibers functionalized with antibacterial and electromagnetic shielding properties

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Wei; Li, Weiya; Gao, Cuicui; Tian, Weicheng [College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620 (China); Sun, Bin [College of Material Science and Engineering, Donghua University, Shanghai 201620 (China); Yu, Dan, E-mail: yudan@dhu.edu.cn [College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620 (China)

    2015-07-01

    Highlights: • We propose a novel modification method to initiate silver electroless plating on PAN fiber without noble metal catalyst. • The silver-plated fiber we fabricated has good electromagnetic shielding effectiveness and antibacterial properties. • The metal layer has good adhesion strength and the properties of the silver-plated fiber can stand 30 cycles of standard washing. - Abstract: Polyacrylonitrile (PAN) fibers with antibacterial, electromagnetic shielding and antistatic functionalities were fabricated in this paper through modifying PAN fibers with (3-aminopropyl)triethoxysilane (APTES) and 3-mercaptopropyltriethoxysilane (MPTES) sequentially and followed with silver electroless plating. The silver layer on PAN fiber surface was characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM) and X-ray diffraction (XRD). The results show that the silver layer was plated uniformly and compactly. The surface resistance of plated fabric was about 40 mΩ/sq on average. The antibacterial tests demonstrate that silver-plated PAN fiber exhibits excellent antibacterial property against S. aureus and E. coli with a non-leaching characteristic. The antibacterial property remains good after 30 cycles of standard washing, which is a strong proof of a durable adhesion between metal layer and fiber. The shielding effectiveness (SE) of silver-plated PAN fabric before and after 30 cycles of standard washing was about 40–80 dB and 35–50 dB, respectively. This resultant fiber can be used in many occasions for reducing or preventing electromagnetic interference (EMI) and electromagnetic hazards.

  6. Comparison of galvanic displacement and electroless methods for deposition of gold nanoparticles on synthetic calcite

    Indian Academy of Sciences (India)

    Chamarthi K Srikanth; P Jeevanandam

    2012-11-01

    Gold nanoparticles have been deposited on synthetic calcite substrate by galvanic displacement reaction and electroless deposition methods. A comparative study has shown that electroless deposition is superior compared to galvanic displacement reaction for uniform deposition of gold nanoparticles on calcite. Characterization of the samples, prepared by two different deposition methods, was carried out by X-ray diffraction, transmission electron microscopy, field emission scanning electron microscopy (FE–SEM) and diffuse reflectance spectroscopy (DRS) measurements. FE–SEM studies prove that smaller nanoparticles of gold are deposited uniformly on calcite if electroless deposition method was employed and DRS measurements show the characteristic surface plasmon resonance of gold nanoparticles.

  7. Hybrid Antifouling and Antimicrobial Coatings Prepared by Electroless Co-Deposition of Fluoropolymer and Cationic Silica Nanoparticles on Stainless Steel: Efficacy against Listeria monocytogenes.

    Science.gov (United States)

    Huang, Kang; Chen, Juhong; Nugen, Sam R; Goddard, Julie M

    2016-06-29

    Controlling formation, establishment, and proliferation of microbial biofilms on surfaces is critical for ensuring public safety. Herein, we report on the synthesis of antimicrobial nanoparticles and their co-deposition along with fluorinated nanoparticles during electroless nickel plating of stainless steel. Plating bath composition is optimized to ensure sufficiently low surface energy to resist fouling and microbial adhesion as well as to exert significant (>99.99% reduction) antimicrobial activity against Listeria monocytogenes. The resulting coatings present hybrid antifouling and antimicrobial character, can be applied onto stainless steel, and do not rely on leaching or migration of the antimicrobial nanoparticles to be effective. Such coatings can support reducing public health issues related to microbial cross-contamination in areas such as food processing, hospitals, and water purification. PMID:27268033

  8. Experimental study of the voids in the electroless copper deposits and the direct measurement of the void fraction based on the scanning electron microscopy images

    International Nuclear Information System (INIS)

    Electroless copper deposits were plated on epoxy substrates in various plating solutions at either a high operating temperature (60 deg. C) or a low one (45 deg. C). Cross section samples were made using epoxy resin cured in room temperature, and then ground, polished and over-etched. The scanning electron microscopy (SEM) images of the over-etched cross section samples show voids in low temperature deposits and solid structure in high temperature ones. The surface morphology images also indicated such structures in low temperature samples. The SEM image of the cross section of a stand-alone deposit prepared on stainless steel substrate shows similar voids observed on etched cross section samples on epoxy board substrates. An image processing program was written using MATLAB to identify the voids in the over-etched cross sections of the deposits from low temperature solutions and thus the void fraction can be directly measured and compared with the previously published simulation results.

  9. Improving copper plating adhesion on glass using laser machining techniques and areal surface texture parameters

    Science.gov (United States)

    He, Baofeng; Petzing, Jon; Webb, Patrick; Leach, Richard

    2015-12-01

    Glass is a promising substitute substrate material being evaluated for electronic packaging technology. Improving the electroless copper plated layer adhesion of the glass is one of the most important considerations for development of the technology. An excimer laser (248 nm) was used for structured texturing of glass surfaces (to improve adhesion) by changing mask dimensions, laser operating parameters and overlapping pitch spacing, and therefore producing a range of micro-scale features. Electroless plated copper adhesion strength was assessed using quantitative scratch testing, demonstrating that micro-patterned structures can significantly improve copper/glass adhesion. New ISO 25178 Part 2 areal surface texture parameters were used to characterise the surface roughness of ablated glass surfaces, and correlated to the scratch testing results. Highly correlated parameters were identified that could be used as predictive surface design tools, directly linking surface topography to adhesion performance, without the need for destructive adhesion quantification via scratch testing.

  10. Hydrofluoric Acid Corrosion Testing on Unplated and Electroless Gold-Plated Samples

    International Nuclear Information System (INIS)

    The Molten Salt Reactor Experiment (MSRE) remediation requires that almost 40 kg of uranium hexafluoride (UF6) be converted to uranium oxide (UO). In the process of this conversion, six moles of hydrofluoric acid (HP) are produced for each mole of UF6 converted

  11. Experimentally validated improvement of IPMC performance through alternation of pretreatment and electroless plating processes

    International Nuclear Information System (INIS)

    It has been known for years that polymers can be stimulated to change shapes and sizes. Electro-active polymers (EAPs) have recently been spotlighted in biomimetic applications due to the properties of energy transduction from the electrical to the mechanical form for actuation. Ionic polymer metal composites (IPMCs) are a type of ionic EAP and considered to be one of the most promising smart materials. IPMCs are light in weight, chemically stable, fast responding and can make large bending deformations under low driving voltages. This study focuses on the fabrication method and performance of IPMCs by using Nafion® films. Tip force optimization is determined by using the Taguchi design of experiment technique

  12. ELECTROLESS PLATING COMPOSITE COATINGS OF Ni-Ti-Re ON THE SURFACE OF DIAMOND

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Diamondtoolsaremadegeneralythroughthepowdermetalurgicalsinterproces.Itisobviousthattheinterfaceenergybetwenthediamondandord...

  13. Research of Kinetics of Electroless Ni-Cu-P Alloy Plating on Polyester Fabric

    Institute of Scientific and Technical Information of China (English)

    CHEN Zhen-bing; CHEN Xiao-li

    2002-01-01

    All the variables that may affect the Ni- Cu-P alloy deposition rate on polyester fabric were studied, and the activation energy and the reaction orders were determined. The deposition rate equation was also derived.

  14. Laser-induced site-selective silver seeding on polyimide for electroless copper plating

    International Nuclear Information System (INIS)

    Ag particles were generated on Ag+-doped polyimide film by laser direct writing, followed by selective copper deposition using the metallic silver particles as seeds. Laser irradiation caused in situ reduction and agglomeration of silver on the polyimide film. The copper lines were less uniform and compact with higher scanning velocity and the width of the deposited copper line could reach 25 μm. Equations of the relationship between scanning velocity and connectivity of the deposited copper patterns have been derived. The process was characterised by AFM, XPS, SEM, and semiconductor characterisation system

  15. Deposition of gold nanoparticles on silica spheres by electroless metal plating technique.

    Science.gov (United States)

    Kobayashi, Yoshio; Tadaki, Yohei; Nagao, Daisuke; Konno, Mikio

    2005-03-15

    A previously proposed method for metal deposition with silver [Kobayashi et al., Chem. Mater. 13 (2001) 1630] was extended to uniform deposition of gold nanoparticles on submicrometer-sized silica spheres. The present method consisted of three steps: (1) the adsorption of Sn(2+) ions took place on surface of silica particles, (2) Ag(+) ions added were reduced and simultaneously adsorbed to the surface, while Sn(2+) was oxidized to Sn(4+), and (3) Au(+) ions added were reduced and deposited on the Ag surface. TEM observation, X-ray diffractometry, and UV-vis absorption spectroscopy revealed that gold metal nanoparticles with an average particle size of 13 nm and a crystal size of 5.1 nm were formed on the silica spheres with a size of 273 nm at an Au concentration of 0.77 M. PMID:15721938

  16. Electroless Ni-P plating with a phytic acid pretreatment on AZ91D magnesium alloy

    International Nuclear Information System (INIS)

    A phytic acid conversion film with especial functional groups was proposed as the pretreatment layer between Ni-P coating and AZ91D magnesium alloy substrate, to replace the traditional pretreatment. In the process, the silane coupling agent was adopted as connector between conversion film and palladium ion with catalysis. The microstructure of the phytic acid conversion coatings was observed using scanning electronic microscopy, while the composition and functional groups were analyzed by energy dispersive spectrometer and Fourier transform infrared spectroscopy. The bonding between Si-OH of the silane coupling agent and hydroxyl of phytic acid was validated by X-ray photoelectron spectroscopy, and the existence of palladium ion was also verified. The subsequent Ni-P deposited on the layer was also characterized by its structure, morphology, and corrosion resistance. The results show that the Ni-P coatings with the phytic acid pretreatment on AZ91D magnesium alloy have good corrosion resistance.

  17. Electroless Ni-P plating with a phytic acid pretreatment on AZ91D magnesium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Cui Xiufang, E-mail: cuixf97721@yahoo.com.cn [School of Materials Science and Chemical Engineering, Harbin Engineering University, 145 Nantong St., Harbin 150001 (China); State Key Laboratory for Corrosion and Protection, Institute of Metal Research, Chinese Academy of Sciences, 62 Wencui Road, Shenyang 110016 (China); Jin Guo; Li Qingfen; Yang Yuyun [School of Materials Science and Chemical Engineering, Harbin Engineering University, 145 Nantong St., Harbin 150001 (China); Li Ying [State Key Laboratory for Corrosion and Protection, Institute of Metal Research, Chinese Academy of Sciences, 62 Wencui Road, Shenyang 110016 (China); Wang Fuhui [School of Materials Science and Chemical Engineering, Harbin Engineering University, 145 Nantong St., Harbin 150001 (China); State Key Laboratory for Corrosion and Protection, Institute of Metal Research, Chinese Academy of Sciences, 62 Wencui Road, Shenyang 110016 (China)

    2010-05-15

    A phytic acid conversion film with especial functional groups was proposed as the pretreatment layer between Ni-P coating and AZ91D magnesium alloy substrate, to replace the traditional pretreatment. In the process, the silane coupling agent was adopted as connector between conversion film and palladium ion with catalysis. The microstructure of the phytic acid conversion coatings was observed using scanning electronic microscopy, while the composition and functional groups were analyzed by energy dispersive spectrometer and Fourier transform infrared spectroscopy. The bonding between Si-OH of the silane coupling agent and hydroxyl of phytic acid was validated by X-ray photoelectron spectroscopy, and the existence of palladium ion was also verified. The subsequent Ni-P deposited on the layer was also characterized by its structure, morphology, and corrosion resistance. The results show that the Ni-P coatings with the phytic acid pretreatment on AZ91D magnesium alloy have good corrosion resistance.

  18. Creating Complex Hollow Metal Geometries Using Additive Manufacturing and Metal Plating

    OpenAIRE

    McCarthy, David Lee

    2012-01-01

    Additive manufacturing introduces a new design paradigm that allows the fabrication of geometrically complex parts that cannot be produced by traditional manufacturing and assembly methods. Using a cellular heat exchanger as a motivational example, this thesis investigates the creation of a hybrid manufacturing approach that combines selective laser sintering with an electroforming process to produce complex, hollow, metal geometries. The developed process uses electroless nickel plating on l...

  19. Micro-scale abrasion behaviour of electroless Ni-P-SiC coating on aluminium alloy

    OpenAIRE

    Franco, M.; Sha, Wei; Malinov, Savko

    2014-01-01

    Electroless nickel (EN) and electroless nickel composite (ENC) coatings were deposited on aluminium alloy substrate, LM24. The micro abrasion test was conducted to study the wear behaviour of the coatings with the effect of SiC concentration. Microhardness of the coatings was tested also. The wear scars were analysed using optical microscope and scanning electron microscope (SEM). The wear resistance was found to be improved in composite coating that has higher microhardness as compared to pa...

  20. Influence of Process Parameters on Microhardness of Electroless Ni-B Coatings

    OpenAIRE

    Prasanta Sahoo; Suman Kalyan Das

    2012-01-01

    Electroless Ni-B coatings have found large applications due to their high hardness and wear resistance. The present paper tries to investigate the influence of coating process parameters on the microhardness of electroless Ni-B coating with the help of Taguchi analysis. Four parameters, namely, bath temperature, concentration of reducing agent, concentration of nickel source, and annealing temperature, are considered and fitted into an L27 orthogonal array to find out the optimized condition ...

  1. Tribological characterization of electroless NiP coatings lubricated with biolubricants

    OpenAIRE

    Ramalho, A; Miranda, J.C.

    2007-01-01

    Electroless nickel (EN) coatings are used in a wide range of applications concerning their excellent mechanical and tribological properties. The incorporation of solid lubricants, such as polytetrafluoroethylene (PTFE), could even improve the properties of the EN coatings. Above all, we can achieve a film with self-lubricating and excellent anti-sticking characteristics. These uses of electroless nickel coatings are widespread in dry contacts. However, it is well known that in the mechanical ...

  2. Electrochromism of the electroless deposited cuprous oxide films

    International Nuclear Information System (INIS)

    Thin cuprous oxide films were prepared by a low cost, chemical deposition (electroless) method onto glass substrates pre-coated with fluorine doped tin oxide. The X-ray diffraction pattern confirmed the Cu2O composition of the films. Visible transmittance spectra of the cuprous oxide films were studied for the as-prepared, colored and bleached films. The cyclic voltammetry study showed that those films exhibited cathode coloring electrochromism, i.e. the films showed change of color from yellowish to black upon application of an electric field. The transmittance across the films for laser light of 670 nm was found to change due to the voltage change for about 50%. The coloration memory of those films was also studied during 6 h, ex-situ. The coloration efficiency at 670 nm was calculated to be 37 cm2/C

  3. Electrochromism of the electroless deposited cuprous oxide films

    Energy Technology Data Exchange (ETDEWEB)

    Neskovska, R. [Faculty of Technical Sciences, University ' St. Clement Ohridski' , Bitola (Macedonia, The Former Yugoslav Republic of); Ristova, M. [Faculty of Natural Sciences and Mathematics, Institute of Physics, P.O. Box 162, Skopje (Macedonia, The Former Yugoslav Republic of)]. E-mail: mristova@iunona.pmf.ukim.edu.mk; Velevska, J. [Faculty of Natural Sciences and Mathematics, Institute of Physics, P.O. Box 162, Skopje (Macedonia, The Former Yugoslav Republic of); Ristov, M. [Macedonian Academy of Sciences and Arts, Skopje, Bul. Krste Misirkov bb, Skopje (Macedonia, The Former Yugoslav Republic of)

    2007-04-09

    Thin cuprous oxide films were prepared by a low cost, chemical deposition (electroless) method onto glass substrates pre-coated with fluorine doped tin oxide. The X-ray diffraction pattern confirmed the Cu{sub 2}O composition of the films. Visible transmittance spectra of the cuprous oxide films were studied for the as-prepared, colored and bleached films. The cyclic voltammetry study showed that those films exhibited cathode coloring electrochromism, i.e. the films showed change of color from yellowish to black upon application of an electric field. The transmittance across the films for laser light of 670 nm was found to change due to the voltage change for about 50%. The coloration memory of those films was also studied during 6 h, ex-situ. The coloration efficiency at 670 nm was calculated to be 37 cm{sup 2}/C.

  4. Effect of Processing Parameters on the Protective Quality of Electroless Nickel-Phosphorus on Cast Aluminium Alloy

    Directory of Open Access Journals (Sweden)

    Olawale Olarewaju Ajibola

    2015-01-01

    Full Text Available The effects of temperature, pH, and time variations on the protective amount and quality of electroless nickel (EN deposition on cast aluminium alloy (CAA substrates were studied. The temperature, pH, and plating time were varied while the surface condition of the substrate was kept constant in acid or alkaline bath. Within solution pH of 5.0–5.5 range, the best quality is obtained in acid solution pH of 5.2. At lower pH (5.0–5.1, good adhesion characterised the EN deposition. Within the range of plating solution pH of 7.0 to 11.5, the highest quantity and quality of EN deposition are obtained on CAA substrate in solution pH of 10.5. It is characterised with few pores and discontinuous metallic EN film. The quantity of EN deposition is time dependent, whereas the adhesion and brightness are not time controlled. The best fit models were developed from the trends of result data obtained from the experiments. The surface morphologies and the chemical composition of the coating were studied using the Jeol JSM-7600F field emission scanning electron microscope.

  5. Plate tectonics

    Digital Repository Service at National Institute of Oceanography (India)

    Chaubey, A.K.

    and ocean floor lie. The plates are in continuous motion at a speed of few centimeters per year over the asthenosphere, which is highly viscous, easily deformable layer between upper and lower mantle. The relative motion between the plates produces new... the newly generated magma, the solidified part of the older magma moves away from the ridge axes. This process is known as seafloor spreading. At subduction zones the old oceanic lithosphere is consumed in the asthenosphere to accommodate the newly...

  6. Synergistic effect between nano-ceramic lubricating additives and electroless deposited Ni-W-P coating

    Science.gov (United States)

    Chen, Min; Cheng, Wushan; Zhao, Zuxin; Huang, Xiaobo

    2013-01-01

    The major solving ways for the material wear are surface modification and lubrication. Currently, the researches at home and abroad are all limited to the single study of either nano-lubricating oil additive or electroless deposited coating. The surface coating has high hardness and high wear resistance, however, the friction reduction performance of the coating with high hardness is not good, the thickness of the coating is limited, and the coating can not regenerate after wearing. The nano-lubricating additives have good tribological performance and self-repair function, but under heavy load, the self-repair rate to the worn surface with the nano-additives is smaller than the wearing rate of the friction pair. To solve the above problems, the Ni-W-P alloy coating and deposition process with excellent anti-wear, and suitable for industrial application were developed, the optimum bath composition and process can be obtained by studying the influence of the bath composition, temperature and PH value to the deposition rate and the plating solution stability. The tribological properties as well as anti-wear and friction reduction mechanism of wear self-repair nano-ceramic lubricating additives are also studied. The ring-block abrasion testing machine and energy dispersive spectrometer are used to explore the internal relation between the coating and the nano-lubricating oil additives, and the tribology mechanism, to seek the synergetic effect between the two. The test results show that the wear resistance of Ni-W-P alloy coating (with heat treatment and in oil with nano-ceramic additives) has increased hundreds times than 45 steel as the metal substrate in basic oil, the friction reduction performance is improved. This research breaks through the bottleneck of previous separate research of the above-mentioned two methods, and explores the combination use of the two methods in industrial field.

  7. Radiotracer and electrochemical studies of the underpotential deposition of thallium and lead in relation to the inhibition of electroless nickel deposition

    International Nuclear Information System (INIS)

    In an attempt to explain the inhibition of metallic compounds in the electroless nickel plating bath, underpotential deposition of thallium or lead onto a silver substrate has been studied by means of the radiotracer and electrochemical methods in alkaline solutions containing complexing agents. It was confirmed by the anodic stripping method that formation of an atomic monolayer of thallium or lead takes place onto the silver substrate in the underpotential range. The radiotracer study also supports these findings for the Ag/Tl+ system. Adsorption of thallous ions onto the silver substrate was found to take place with the Freundlich type mechanism in the potential range before the onset of underpotential deposition of thallium. The linear dependence of ΔUp (underpotential shift in anodic stripping peaks between bulk and monolayer) on Δphi (difference in work function) similar to Gerischer's results was also observed in this work. The concepts of underpotential deposition of thallium or lead onto nickel substrate seems to be useful for explaining the inhibition effect of these metals in the electroless nickel deposition. (auth.)

  8. Investigation on a Non-cyanide Plating Process of Ni-P Coating on Magnesium Alloy AZ91D

    Institute of Scientific and Technical Information of China (English)

    Bonian HU; Gang YU; Jueling CHEN; Ying LI; Liyuan YE

    2005-01-01

    In this research we presented a non-cyanide plating process of Ni-P alloy coating on Mg alloy AZ91D. By applying a new process flow of electroless nickel plating in which zinc coating is used as transition of Ni-P coating on Mg alloy AZ91D, the process of copper transition coating plated in the cyanides bath can be replaced. A new bath composed of NiSO4 was established by orthogonal test. The results show that zinc transition coating can increase the adhesion and pH 4.0 and 95℃, respectively. The present process flow is composed of ultrasonic cleaning→alkaline cleaning→acid pickling→activation→double immersing zinc→electroplating zinc→electroless nickel plating→passivation treatment.The present non-cyanide process of electroless nickel plating is harmless to our surroundings and Ni-P coating on Mg alloy AZ91D produced by present process possesses good adhesion and corrosion resistance.

  9. Effect of polytetrafluoroethylene content on electrochemical anticorrosion behaviors of electroless deposited Ni-P and Ni-P-polytetrafluoroethylene coatings in seawater

    Energy Technology Data Exchange (ETDEWEB)

    Wang Jianfei; Tian Jintao, E-mail: jttian@ouc.edu.cn; Liu Xuezhong; Yin Yansheng; Wang Xin

    2011-07-01

    The Ni-P and Ni-P-polytetrafluoroethylene (PTFE) coatings with various PTFE contents were electroless deposited on carbon steel and characterized through X-ray diffraction, scanning electron microscopy, and energy dispersive X-ray spectroscopy. The microstructural morphologies of the coatings significantly varied with the PTFE content. As a result, the electrochemical anticorrosion capabilities were seriously decreased with the increase of the PTFE content. The coating with a trace PTFE (PTFE emulsion concentration of 0.2 mL/L in the plating bath) possessed excellent anticorrosion both in sterilized and unsterilized seawater which has been attributed to the absence of nano pores blocked by the incorporated trace PTFE nano particles.

  10. Comparison of the coating properties and corrosion rates in electroless Ni-P/PTFE composites prepared by different types of surfactants

    Science.gov (United States)

    Mafi, Iman R.; Dehghanian, Changiz

    2011-08-01

    The effects of the addition of three types of surfactants (cationic, anionic, non-ionic) at different concentrations in the plating bath on the deposition rate, PTFE content and surface morphology of electroless Ni-P/PTFE composite coatings were investigated. It was demonstrated that the cationic and non-ionic surfactants created a uniform distribution of PTFE particles in the coatings. The effects of the surfactant type and concentration on the corrosion properties of Ni-P/PTFE coatings were also studied. The corrosion resistance was increased by the incorporation of PTFE particles into the Ni-P matrix. The level of improvement depended largely on the type and concentration of the applied surfactants.

  11. The influence of experimental parameters on the structure, morphology and electrochemical behavior of Pd-P thin films prepared by electroless deposition

    International Nuclear Information System (INIS)

    Pd-P thin films over carbon steel were prepared by electroless deposition, using sodium hypophosphite as reducing agent. The influence of the plating conditions, on the properties of the coatings is investigated in detail. The deposits morphology was assessed by Scanning Electron Microscope and Atomic Force Microscopy imaging, their compositions and respective elements distribution determined by Energy Dispersive X-ray Spectrometry and structural information obtained by X-ray diffraction. It has been observed that the amount of co-deposited P depends on both the deposition time and the employed NaH2PO2 concentration, which in turn dictates the degree of amorphicity of the so-prepared Pd-P layers. The modified electrodes electrochemical behaviour, evaluated by cyclic voltammetry in alkaline media, revealed that the hydrogen adsorption/absorption process and the hydrogen evolution reaction are enhanced on alloys with phosphorus content below 10 at.%

  12. The influence of experimental parameters on the structure, morphology and electrochemical behavior of Pd-P thin films prepared by electroless deposition

    Energy Technology Data Exchange (ETDEWEB)

    Robertis, Eveline de [Instituto de Quimica de Sao Carlos, USP., Av. Trabalhador Sancarlense 400, CP 780, CEP 13566-590 Sao Carlos, SP (Brazil)], E-mail: erobertis@yahoo.com.br; Abrantes, Luisa M. [CQB, Departamento de Quimica e Bioquimica da Faculdade de Ciencias da Universidade de Lisboa, Campo Grande, 1749-016 Lisboa (Portugal)], E-mail: luisa.abrantes@fc.ul.pt; Motheo, Artur J. [Instituto de Quimica de Sao Carlos, USP., Av. Trabalhador Sancarlense 400, CP 780, CEP 13566-590 Sao Carlos, SP (Brazil)], E-mail: artur@iqsc.usp.br

    2008-07-31

    Pd-P thin films over carbon steel were prepared by electroless deposition, using sodium hypophosphite as reducing agent. The influence of the plating conditions, on the properties of the coatings is investigated in detail. The deposits morphology was assessed by Scanning Electron Microscope and Atomic Force Microscopy imaging, their compositions and respective elements distribution determined by Energy Dispersive X-ray Spectrometry and structural information obtained by X-ray diffraction. It has been observed that the amount of co-deposited P depends on both the deposition time and the employed NaH{sub 2}PO{sub 2} concentration, which in turn dictates the degree of amorphicity of the so-prepared Pd-P layers. The modified electrodes electrochemical behaviour, evaluated by cyclic voltammetry in alkaline media, revealed that the hydrogen adsorption/absorption process and the hydrogen evolution reaction are enhanced on alloys with phosphorus content below 10 at.%.

  13. Effect of polytetrafluoroethylene content on electrochemical anticorrosion behaviors of electroless deposited Ni-P and Ni-P-polytetrafluoroethylene coatings in seawater

    International Nuclear Information System (INIS)

    The Ni-P and Ni-P-polytetrafluoroethylene (PTFE) coatings with various PTFE contents were electroless deposited on carbon steel and characterized through X-ray diffraction, scanning electron microscopy, and energy dispersive X-ray spectroscopy. The microstructural morphologies of the coatings significantly varied with the PTFE content. As a result, the electrochemical anticorrosion capabilities were seriously decreased with the increase of the PTFE content. The coating with a trace PTFE (PTFE emulsion concentration of 0.2 mL/L in the plating bath) possessed excellent anticorrosion both in sterilized and unsterilized seawater which has been attributed to the absence of nano pores blocked by the incorporated trace PTFE nano particles.

  14. Electroless Functionalization of Silver Films by Its Molecular Doping.

    Science.gov (United States)

    Naor, Hadas; Avnir, David

    2015-12-01

    We present a methodology which by far extends the potential applications of thin conductive silver films achieved by an electroless molecular doping process of the metal with any of the endless functional molecules that the large library of organic molecules offer. The resulting metallic films within which the molecule is entrapped--molecule@Ag--carry both the classical chemical and physical properties of silver films, as well as the function of the entrapped molecule. Raman measurements of the organic molecules from within the silver films provide the first spectroscopic observations from within silver, and clearly show that entrapment, a three-dimensional process, and adsorption, a two-dimensional process, on silver films are distinctly different processes. Three organic molecules, the cationic Neutral red, the anionic Congo red, and the antibacterial agent chlorhexidine digluconate (CH), were used to demonstrate the generality of this method for various types of molecules. We studied the sensitivity of the film conductivity to the type of the molecule entrapped within the film, to its concentration, and to temperature. Dual functionality was demonstrated with CH@Ag films, which are both conductive and have prolonged and high antibacterial activity, a combination of properties that has been unknown so far. PMID:26571199

  15. Electroless Ni-P-ferrite composite coatings for microwave applications

    Indian Academy of Sciences (India)

    Ramesh Chandra Agarwala

    2005-11-01

    Electroless, EL coating technique is one of the elegant ways of coating by controlling the temperature and pH of the coating bath in which there is no usage of electric current. It is estimated that the market for this chemistry will increase at a rate of about 15% per year. Use of microwave energy for synthesis of material with novel microstructures is an exciting new field in material science with enormous application. In this investigation, nanograined BaZn2-CoFe16O27 ( = 0.0, 0.4, 0.8, 1.2, 1.6 and 2.0) powders have been synthesized by citrate precursor method followed by heat treatment at various specified temperatures like 650, 750 and 850°C for 3 h in the furnace. In addition heat treatments are also carried out in the microwave oven of the power rating of 760 W. The powders thus produced have been characterized by SEM, EPMA, VSM, XRD and thermal analysis techniques. As a forward step towards EL nano-composite coatings, Ni-P- ( = BaZn2- CoFe16O27) coatings with thickness less than ∼ 0.1 mm thick has been produced. Such coating exhibits absorption of microwave in the range of 12-18 GHz up to about 20 db depending upon the volume fraction of the ferrite particles embedded in the Ni-P matrix.

  16. Morphology Investigation of Electrolessly Deposited Ag Film on Ag-Activated p-Type Silicon(111) Wafer

    Institute of Scientific and Technical Information of China (English)

    TONG, Hao; WANG, Chun-Ming

    2006-01-01

    A method of electroless silver deposition on silver activated p-type silicon(111) wafer was proposed. The silver seed layer was deposited firstly on the wafer in the solution of 0.005 mol/L AgNO3 + 0.06 mol/L HF. Then the silver film was electrolessly deposited on the seed layer in the electroless bath of AgNO3+NH3+acetic acid+NH2NH2(pH 10.2). The morphology of the seed layer and the silver films prepared under the condition of the different bath composition was compared by atomic force microscopy. The reflectance of the silver films with different thickness was characterized by Fourier transform infrared spectrometry. The experimental results indicate that the seed layer possesses excellent catalytic activity toward electroless silver deposition and rotating of the silicon wafer during the electroless silver deposition could lead to formation of the smoother silver film.

  17. PREPARATION AND ANALYSIS OF Ni-P-Zn ELECTROLESS DEPOSITION FROM ALKALT BATH

    Institute of Scientific and Technical Information of China (English)

    Y.S. Huang; F.Z. Cui

    2005-01-01

    Electroless Ni-P-Zn alloys deposited from alkali bath were investigated in this paper. The deposition bath contained nickel sulfate, zinc chloride and hypophosphate. The process parameters, such as temperature, pH and zinc salt concentration were presented and discussed.The microstructure of the coatings was studied by XRD and SEM. The cathode glowing discharge characters of Ni-P-Zn depositions were studied with luminous Neon lamps. Electrodes deposited by electroless Ni-P alloys were apt to sputter during luminous working hours. Electroless Ni-P-Zn depositions improved the discharge characters of the electrodes.With the concentration of zinc in the deposition rising to 4wt%, electrode sputter was largely restrained. The thickness of the deposition also influenced the discharge characters of the electrode. To avoid electrode sputter, the concentration of zinc has to rise with the thickness of the depositions.

  18. Electrochemical Characteristics of Titanium for Dental Implants in Case of the Electroless Surface Modification

    Directory of Open Access Journals (Sweden)

    Klimecka-Tatar D.

    2016-06-01

    Full Text Available In the paper the results of research under effect of electroless phosphate coating of titanium dental implants on potentiokinetic polarization characteristic obtained in artificial saliva were presented. On the basis of electrochemical studies it was concluded that the electroless process of phosphating beneficialy effect on corrosion characteristic of titanium determined in solution simulating the oral cavity. Furthermore, the proposed technique of chemical treatment of titanium surface is conducive to the homogeneous development of the surface, which is extremely important from the point of view of titanium implants biointegration. Phosphating treatment affect on the development of surface geometry, resulting in a slight increase in roughness parameters (Ra, Rz and Rmax. The temperature increase of electroless phosphating treatment promotes the rate of conversion layer formation, whereas the effect of temperature of the chemical treatment efficiency is secondary important at longer exposure times (e.g. 45 minutes.

  19. Synthesis and characterization of nanocrystalline silver coating of fly ash cenosphere particles by electroless process.

    Science.gov (United States)

    Shukla, S; Seal, S; Schwarz, S; Zhou, D

    2001-12-01

    Electroless nanocrystalline Ag coating of fly ash cenosphere particles utilizing a Sn-Pd catalyst system is demonstrated in this article. The deposition of pure metallic nanocrystalline Ag on the fly ash cenosphere particle surface is confirmed by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD) analysis. Under the described conditions of electroless coating, average nanocrystalline Ag-coating thickness is observed to be approximately 220 nm, using a focused ion beam technique, which is less than that observed by transmission electron microscopy (TEM) (260-360 nm). TEM observation further reveals that the Ag-coating is made up of 50 nm Ag nanocrystallites, which is comparable with the size of approximately 37 nm obtained from the XRD data. The mechanism of the electroless Ag-coating process is discussed. Ag-coated fly ash particles find applications in manufacturing conducting polymers for electromagnetic interference shielding applications. PMID:12914083

  20. Electroless Ni-Co-P Coating of Cenospheres Using Ag(NH3)2+ Activator

    Institute of Scientific and Technical Information of China (English)

    ZENG Ai-xiang; XIONG Wei-hao

    2004-01-01

    Electroless Ni-Co-P-coating of fly-ash cenosphere particles is demonstrated in the present investigation. The Electroless Ni-Co-P-coating process is modified by replacing the conventional sensitization and activation steps with only using activation step with Ag(NH3)2+ activator. The cenospheres are characterized by scanning electron microscope (SEM),energy dispersive spectroscopy (EDX), X-ray diffraction analysis (XRD) and X-ray photoelectron spectroscopy (XPS)during and after the coating process. Relatively uniform coating is obtained under the given coating conditions. The possible mechanism of electroless Ni-Co-P-coating of cenospheres utilizing Ag(NH3)2+ activator is suggested. The low density Ni-Co-P coated cenospheres may be utilized for manufacturing conducting polymers for EMI-shielding application and microwave absorbing materials.

  1. Development of process technologies for improvement of electroless nickel coatings properties

    International Nuclear Information System (INIS)

    This paper describes research and technology developments that enable to improve nickel electroless coating properties. This work deals with: (a) different methods in order to achieve Ni-P-Mo coatings. (b) Other development is related with coatings with addition of hard particles such as SiC, WC or Al2O3,(c) Electroless nickel deposits on PBT and austempered ductile iron (ADI). (d) In addition, nickel coatings were deposited on powder metallic pieces and finally, electroless nickel coatings, in conjunction with layers from thermal spray process were formed. Characterization of all coatings by means of optical microscopy, scanning electron microscopy, micro-hardness, wear and corrosion tests were carried out. Results indicate positive increment in both mechanical and electrochemical properties which enhance field applications in Mexican industry.

  2. Salt Spray Test to Determine Galvanic Corrosion Levels of Electroless Nickel Connectors Mounted on an Aluminum Bracket

    Science.gov (United States)

    Rolin, T. D.; Hodge, R. E.; Torres, P. D.; Jones, D. D.; Laird, K. R.

    2014-01-01

    During preliminary vehicle design reviews, requests were made to change flight termination systems from an electroless nickel (EN) connector coating to a zinc-nickel (ZN) plating. The reason for these changes was due to a new NASA-STD-6012 corrosion requirement where connectors must meet the performance requirement of 168 hr of exposure to salt spray. The specification for class F connectors, MIL-DTL-38999, certifies the EN coating will meet a 48-hr salt spray test, whereas the ZN is certified to meet a 168-hr salt spray test. The ZN finish is a concern because Marshall Space Flight Center has no flight experience with ZN-finished connectors, and MSFC-STD-3012 indicates that zinc and zinc alloys should not be used. The purpose of this test was to run a 168-hr salt spray test to verify the electrical and mechanical integrity of the EN connectors and officially document the results. The salt spray test was conducted per ASTM B117 on several MIL-DTL-38999 flight-like connectors mounted to an aluminum 6061-T6 bracket that was alodined. The configuration, mounting techniques, electrical checks, and materials used were typical of flight and ground support equipment.

  3. The Effect and Mechanism of Nano-Cu Lubricating Additives on the Electroless Deposited Ni-W-P Coating

    Institute of Scientific and Technical Information of China (English)

    CHEN Min; JIANG Xiaomin; ZHAO Zuxin; HUANG Xiaobo

    2012-01-01

    The coating and deposition process with excellent anti wear and suitable for industrial application were developed,and the optimum bath composition and process were obtained by studying the influence of the bath composition,temperature and pH value on the deposition rate and the plating solution stability.Moreover,the tribological properties of nano-Cu lubricating additives and electroless deposited Ni-W-P coating as well as their synergistic effect are researched using ring-block abrasion testing machine and energy dispersive spectrometer.Research results show that Ni-W-P alloy coating and nano-Cu lubricating additive have excellent synergistic effect,e g,the wear resistance of Ni-W-P alloy coating (with heat treatment and the oil with nano-Cu additives) has increased hundreds times than 45 steel as the metal substrate with the basic oil,and zero wear is achieved,which breaks through the bottleneck of previous separate research of the above-mentioned two aspects.

  4. The Microstructure of Ni Layer on Single-Walled Carbon Nanotubes Prepared by an Electroless Coating Process

    Directory of Open Access Journals (Sweden)

    Weixue Li

    2011-01-01

    Full Text Available The single-walled carbon nanotubes (SWNTs, diameter: 2~3 nm, which were obtained in the suspension of purification solution, with Ni-P coating layers were obtained by an electroless deposition process. The SWNTs before and after coating were characterized by transmission electron microscopy (TEM and energy dispersive spectrometry (EDS. An Ni-P layer on individual nanotube with thickness of 20 nm can be obtained after the deposition process. The X-ray diffraction (XRD and selected area electron diffraction (SAED analysis of Ni-P SWNTs before and after heat treatment show that the heat treatment caused the transformation of the amorphous Ni-P layer to the nanocrystalline Ni-P (crystalline Ni and Ni3P intermetallic compound layer. The XRD pattern of SWNTs with Ni-P layers after heat treatment revealed that the crystal structures of Ni in plating layer contained: hexagonal close-packed (hcp structure and face-centered cubic (fcc structure. The lattice parameters of Ni (fcc and Ni3P are larger than the bulk's, indicting that the lattice expansion has taken place. However, the lattice parameter of Ni (hcp has no difference from the bulk's.

  5. Electroless deposition, post annealing and characterization of nickel films on silicon

    Indian Academy of Sciences (India)

    Subir Sabharwal; Siddharth Palit; R B Tokas; A K Poswal; Sangeeta

    2008-10-01

    Electroless deposition of nickel (EN) films on -type silicon has been investigated under different process conditions. The interface between the film and substrate has been characterized for electrical properties by probing the contact resistances. X-ray diffraction and atomic force microscopy have been performed to obtain information about the structural and morphological details of the films. As a comparative study, nickel films have also been sputter deposited on silicon substrates. An as-deposited electroless film is observed to form non-ohmic contact while in a sputtered film prepared without the application of substrate heating, the formation of metal–insulating–semiconductor type junction is seen.

  6. MONTE-CARLO SIMULATION FOR ATOMIC DEPOSITION OF AMORPHOUS ELECTROLESS Ni80P20 COATING

    Institute of Scientific and Technical Information of China (English)

    K.S. Guan; H.R. Bai; Z.W. Wang; Y.S. Yin

    2002-01-01

    Atomic growth process and structure of Amorphous Electroless Coating have beenstudied, using Monte-Carlo simulation method. The simulation results of amorphousNi80P20 coating show that PDFs are in accordance with practical values. The mi-grations of adatoms in coating's growth are different from that of solidification ofamorphous materials. In some cases, the migrated adatoms in the process of growthof amorphous coating are not enough to occupy all vacancies and traps, so the amor-phous coating is micro-porous. The immovable probability k and the largest migrationdistance of adatoms, which lie on the electroless bath components, affect the PDF,volume density and microporosity remarkably.

  7. Electromagnetic transport properties and magnetoresistance of La0.7Ca0.2Sr0.1MnO3-Ag composites prepared by electroless process

    International Nuclear Information System (INIS)

    A series of bulk polycrystalline La0.7Ca0.2Sr0.1MnO3 (LCSMO)-Ag composites were prepared by electroless plating process and several kinds of physical properties have been studied systemically. According to the results of X-ray diffraction (XRD), scanning electron microscopy (SEM), and electromagnetic transport properties, we can see that Ag-added segregated at the surfaces or interfaces of LCSMO grains. The metal-insulator transition temperature (TP) and Curie temperature (Tc) were almost unchanged but ρ decreased with increasing plating time. We also observed Ag-added can significantly enhance the magnetoresistance (MR) near TP under a low applied field (3000 Oe) and the room temperature MR reached to 35% under 20 kOe, which is encouraging for practical applications. We can suggest that improved grain boundary effect by Ag-added is responsible for the enhancement. - Graphical abstract: Magnetic field dependence of the MR for the composites at 298 K. The inset is the different silver-plating time dependence of the variation of MR at 2 T

  8. Evaluation of silver-coated stainless steel bipolar plates for fuel cell applications

    Science.gov (United States)

    Huang, Ing-Bang

    In this study, computer-aided design and manufacturing (CAD/CAM) technology were applied to develop and produce stainless steel bipolar plates for DMFC (direct methanol fuel cell). Effect of surface modification on the cell performance of DMFC was investigated. Surface modifications of the stainless steel bipolar plates were made by the electroless plating method. A DMFC consisting of silver coated stainless steel as anode and uncoated stainless steel as cathode was assembled and evaluated. The methanol crossover rate (R c) of the proton exchange membrane (PEM) was decreased by about 52.8%, the efficiency (E f) of DMFC increased about 7.1% and amounts of methanol electro-oxidation at the cathode side (M co) were decreased by about 28.6%, as compared to uncoated anode polar plates. These measurements were determined by the transient current and mathematical analysis.

  9. INTEGRATED USE OF RAPID PROTOTYPING AND METAL PLATING TECHNIQUES FOR DEVELOPMENT OF MICRO AIR VEHICLES

    Directory of Open Access Journals (Sweden)

    Dr. K. ELANGOVAN,

    2011-01-01

    Full Text Available This paper describes the synergistic application of rapid prototyping and metal plating technologies for development of micro air vehicles (MAV with high strength-to-weight characteristic. Stereolithography and fused deposition techniques are employed to fabricate complex thermoplastic MAV prototypes with significant time-compression in production cycle. Electroless and electrolytic deposition processes are custom developed to deposit thin metallic foils of nickel and chromium over thermoplastic MAV prototypes. Plating plant with inherent provision for variation of process parameters is established and proof-of-concept studies are carried on plating of MAV prototypes. Experiments are conducted on metal plated thermoplastic test specimens for evaluating the mechanical behaviour and structural integrity properties. Present study is a conclusive demonstration of the use of layered manufacturing techniques in quick realisation of flight-worthy MAV systems.

  10. Fabrication of cube textured Au/Ni template using electoless-plating

    International Nuclear Information System (INIS)

    We fabricated the Au/Ni template for YBCO coated conductors and evaluated texture formation and the microstructural evolution. The cube textured Ni substrate was fabricated by rolling and recrystallization annealing, and subsequently Au layer formed on the substrate by electroless-plating method. The texture was evaluated by pole-figure with x-ray goniometer with orientation distribution function (ODF) analysis. The surface roughness and grain boundary morphology of template were characterized by atomic force microscopy (AFM). We observed that Au layer deposited epitaxially on Ni substrate and formed a strong cube texture when plating time was optimized. The full-width at half-maximum (FWHM) was 8.4 degree for out-of-plane and 9.98 degree for in-plane texture for plating time of 30 min. Microstructural observation showed that the Au layer was homogeneous and dense without formation of crack/microcrack. In addition, we observed that root-mean-square (RMS) and depth of grain boundary were 14.6 nm and 160 for the Au layer, respectively, while those were 27.0 nm and 800 for the Ni substrate, indicating that the electroless-plated Au layer had relatively smooth surface and effectively mollified grain groove.

  11. Electroless porous silicon formation applied to fabrication of boron-silica-glass cantilevers

    DEFF Research Database (Denmark)

    Teva, Jordi; Davis, Zachary James; Hansen, Ole

    2010-01-01

    This work describes the characterization and optimization of anisotropic formation of porous silicon in large volumes (0.5-1 mm3) of silicon by an electroless wet etching technique. The main goal is to use porous silicon as a sacrificial volume for bulk micromachining processes, especially in cas...

  12. A novel electroless method to prepare a platinum electrocatalyst on diamond for fuel cell applications

    Science.gov (United States)

    Lyu, Xiao; Hu, Jingping; Foord, John S.; Wang, Qiang

    2013-11-01

    A novel electroless deposition method was demonstrated to prepare a platinum electrocatalyst on boron doped diamond (BDD) substrates without the need for pre-activation. This green method addresses the uniformity and particle size issues associated with electrodeposition and circumvents the pre-activation procedure which is necessary for conventional electroless deposition. The inert BDD substrate formed a galvanic couple with an iron wire, to overcome the activation barrier associated with conventional electroless deposition on diamond, leading to the formation of Pt nanoparticles on the electrode surface in a galvanic process coupled to a chemical process. When sodium hypophosphite was employed as the reducing agent to drive the electroless reaction Pt deposits which were contaminated with iron and phosphorus resulted. In contrast, the reducing agent ascorbic acid gave rise to high purity Pt nanoparticles. Optimal deposition conditions with respect to bath temperature, pH value and stabilizing additives are identified. Using this approach, high purity and uniformly distributed platinum nanoparticles are obtained on the diamond electrode surface, which demonstrate a high electrochemical activity towards methanol oxidation.

  13. Effects of Pretreatment on the Structure And Properties of Electroless Nickel Coatings

    DEFF Research Database (Denmark)

    Møller, Per; Deng, Hong

    1994-01-01

    The pretreatment process can significantly affect the corrosion resistance of electroless nickel (EN) coatings One of the most important reasons is that different pretreatment processes can give different surface morphologies of the substrate. The scanning electron microscope (SEM) and the scanning...

  14. Effect of Rare Earth Metals on Structure and Properties of Electroless Co-B Alloy Coating

    Institute of Scientific and Technical Information of China (English)

    宣天鹏; 张雷; 黄秋华

    2002-01-01

    The effect of rare earth metals cerium, lanthanum and yttrium on chemical composition, structure and properties of electroless Co-B alloy coating was studied. By plasma transmitting spectrograph, electron energy spectrometer, X-ray diffractometter, micro-hardometer and vibratory sample magnetometer the chemical constitution, structure and properties of the alloy coatings were analyzed and inspected. The results show that with a tiny quantity of rare earth metal added into Co-B alloy coating, the content of boron is decreased in the alloy coatings, and the kinds of rare earth metal have enormous effect on the structure and properties of electroless Co-B alloy coating. At the same time electroless Co-B alloy with amorphous structure is transformed to electroless Co-B-RE alloy with microcrystalline or crystalline structure. In this way microhardness of the coatings is increased remarkably. Cerium and lanthanum would also increase the saturated magnetic intensity and decrease coercitive force of the coating. So soft magnetization of the coatings would be improved.

  15. Electroless deposition of palladium at bare and templated liquid/liquid interfaces.

    Science.gov (United States)

    Dryfe, Robert A W; Simm, Andrew O; Kralj, Brett

    2003-10-29

    A simple, electroless approach to metallize the liquid/liquid interface is reported. The method is illustrated with the deposition of Pd at the bare water/1,2-dichloroethane interface, and for the "templated" deposition of Pd within the 100 nm diameter pores of gamma-alumina membranes. PMID:14570460

  16. Thermo-physical properties of boron carbide reinforced copper composites fabricated by electroless deposition process

    International Nuclear Information System (INIS)

    Highlights: ► B4C/Cu composites were prepared by spark plasma sintering (SPS). ► Electroless deposition of copper on the B4C particles surface was introduced. ► The salt-based colloid palladium was used in the electroless deposition. ► The uniform surface copper coating over B4C particles surface was formed. - Abstract: B4C/Cu composites with enhanced thermal–physical properties were prepared by spark plasma sintering (SPS) after the pretreatment of electroless deposition of copper on the boron carbide particles surface. The boron carbide particles underwent acid treatment, salt-based colloid palladium activation process, and electroless copper deposition on their surface respectively. Samples were analyzed by X-ray diffraction, scanning electron microscopy, and energy dispersive spectrometer in terms of microstructure and chemical composition. The microstructure investigated by SEM shows that high quality copper deposits are obtained on the B4C particles surface accompanied by the good interfacial contact between the copper and the pretreated B4C powder in the sintered sample. It was found that the thermal conductivity decreased as B4C volume fraction increased in copper matrix, while the coefficient of thermal expansion increased

  17. Effect of Addition of Polytetrafluoroethylene (PTFE) and Silicon Carbide (SiC) on Properties of Electroless Nickel Alloy Coatings

    Institute of Scientific and Technical Information of China (English)

    WU Yu-cheng; HU Xiao-ye; WANG Wen-fang; HUANG Xin-min

    2004-01-01

    Electroless nickel (copper)-phosphorus-silicon carbide (SiC)-polytetrafluoroethylene (PTFE) composite coatings were prepared by adding SiC and PTFE into electroless nickel (copper)-phosphorus alloy baths. The effects of addition of SiC and PTFE on depositing rate, microhardness, wear resistance and anti-friction of the resulted composite coatings were studied. The results indicated that electroless nickel (copper)-phosphorus alloy coatings were greatly improved in depositing rate, microhardness, wear resistance and antifriction by co-deposited proper amount of SiC and PTFE.

  18. Platinum-ruthenium bimetallic clusters on graphite: a comparison of vapor deposition and electroless deposition methods.

    Science.gov (United States)

    Galhenage, Randima P; Xie, Kangmin; Diao, Weijian; Tengco, John Meynard M; Seuser, Grant S; Monnier, John R; Chen, Donna A

    2015-11-14

    Bimetallic Pt-Ru clusters have been grown on highly ordered pyrolytic graphite (HOPG) surfaces by vapor deposition and by electroless deposition. These studies help to bridge the material gap between well-characterized vapor deposited clusters and electrolessly deposited clusters, which are better suited for industrial catalyst preparation. In the vapor deposition experiments, bimetallic clusters were formed by the sequential deposition of Pt on Ru or Ru on Pt. Seed clusters of the first metal were grown on HOPG surfaces that were sputtered with Ar(+) to introduce defects, which act as nucleation sites for Pt or Ru. On the unmodified HOPG surface, both Pt and Ru clusters preferentially nucleated at the step edges, whereas on the sputtered surface, clusters with relatively uniform sizes and spatial distributions were formed. Low energy ion scattering experiments showed that the surface compositions of the bimetallic clusters are Pt-rich, regardless of the order of deposition, indicating that the interdiffusion of metals within the clusters is facile at room temperature. Bimetallic clusters on sputtered HOPG were prepared by the electroless deposition of Pt on Ru seed clusters from a Pt(+2) solution using dimethylamine borane as the reducing agent at pH 11 and 40 °C. After exposure to the electroless deposition bath, Pt was selectively deposited on Ru, as demonstrated by the detection of Pt on the surface by XPS, and the increase in the average cluster height without an increase in the number of clusters, indicating that Pt atoms are incorporated into the Ru seed clusters. Electroless deposition of Ru on Pt seed clusters was also achieved, but it should be noted that this deposition method is extremely sensitive to the presence of other metal ions in solution that have a higher reduction potential than the metal ion targeted for deposition. PMID:26018140

  19. Minimizing the bimetallic bending for cryogenic metal optics based on electroless nickel

    Science.gov (United States)

    Kinast, Jan; Hilpert, Enrico; Lange, Nicolas; Gebhardt, Andreas; Rohloff, Ralf-Rainer; Risse, Stefan; Eberhardt, Ramona; Tünnermann, Andreas

    2014-07-01

    Ultra-precise metal optics are key components of sophisticated scientific instruments in astronomy and space applications. Especially for cryogenic applications, a detailed knowledge and the control of the coefficient of thermal expansion (CTE) of the used materials are essential. Reflective optical components in IR- and NIR-instruments primarily consist of the aluminum alloy Al6061. The achievable micro-roughness of diamond machined and directly polished Al6061 does not fulfill the requirements for applications in the visible spectral range. Electroless nickel enables the reduction of the mirror surface roughness to the sub-nm range by polishing. To minimize the associated disadvantageous bimetallic effect, a novel material combination for cryogenic mirrors based on electroless nickel and hypereutectic aluminum-silicon is investigated. An increasing silicon content of the aluminum material decreases the CTE in the temperature range to be considered. This paper shows the CTE for aluminum materials containing about 42 wt% silicon (AlSi42) and for electroless nickel with a phosphorous content ranging from 10.5 to 13 %. The CTE differ to about 0.5 × 10-6 K-1 in a temperature range from -185 °C (LN2) to 100 °C. Besides, the correlations between the chemical compositions of aluminum-silicon materials and electroless nickel are shown. A metrology setup for cryo-interferometry was developed to analyze the remaining and reversible shape deviation at cryogenic temperatures. Changes could be caused by different CTE, mounting forces and residual stress conditions. In the electroless nickel layer, the resulting shape deviation can be preshaped by deterministic correction processes such as magnetorheological finishing (MRF) at room temperature.

  20. Microstructural and mechanical characterizations of a novel HVOF-sprayed WC-Co coating deposited from electroless Ni–P coated WC-12Co powders

    Energy Technology Data Exchange (ETDEWEB)

    Jafari, M., E-mail: majid_jafari@ma.iut.ac.ir [Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of); Iranian Surface Research and Engineering Centre, Isfahan 84155-337 (Iran, Islamic Republic of); Enayati, M.H.; Salehi, M. [Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of); Iranian Surface Research and Engineering Centre, Isfahan 84155-337 (Iran, Islamic Republic of); Nahvi, S.M. [Iranian Surface Research and Engineering Centre, Isfahan 84155-337 (Iran, Islamic Republic of); Park, C.G. [Department of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang 790-784 (Korea, Republic of)

    2013-08-20

    In this research, a novel WC-Co coating was deposited from electroless Ni–P coated WC-12Co powders using high velocity oxygen fuel (HVOF) process. Toward this purpose, an electroless Ni–P plating process was used to develop a uniform Ni–P layer on the surface of WC-12Co powders. The obtained Ni–P coated powders were then used as HVOF feedstock material. Microstructural characteristics of the Ni–P coated WC-12Co powders and the resultant coating, which is denoted as Ni–P modified coating, were investigated using X-ray diffractometry (XRD) and high resolution field emission scanning electron microscopy (HR FE SEM). The micro-hardness, elastic modulus and fracture toughness measurements were executed to evaluate the mechanical properties of the Ni–P modified coating. For comparison, the same experiments were performed on two conventional HVOF sprayed WC-12Co and WC-17Co coatings. The Ni–P modified WC-12Co coating showed a dense structure with extremely low porosity of ∼0.3% which was much lower than that of WC-12Co and WC-17Co coatings. Besides, it was observed that the Ni–P modified coating has undergone negligible decarburization of 2.6% as compared to conventional WC-12Co and WC-17Co coatings with that of 16.3 and 17.6%. The Ni–P modified coating showed the maximum hardness of ∼11.45 GPa, while lower hardness values of 10.98 and 10.59 GPa were measured for the WC-12Co and WC-17Co coatings. The fracture toughness of Ni–P modified WC-12Co coating was found to be 9.86 MPa m{sup 1/2}, indicating 71.2 and 61.1% increase in comparison with WC-12Co and WC-17Co coatings, respectively.

  1. INFLUENCE OF SURFACTANTS ON THE CORROSION PROPERTIES OF CHROMIUM-FREE ELECTROLESS NICKEL DEPOSIT ON MAGNESIUM ALLOY

    OpenAIRE

    JOTHI SUDAGAR; RUAN DEWEN; YAQIN LIANG; RASU ELANSEZHIAN; JIANSHE LIAN

    2012-01-01

    Influence of surfactants on the corrosion properties of chromium-free electroless nickel deposit were investigated on AZ91D magnesium alloy. The corrosion tests were carried out by immersion test (1 M HCl) and electrochemical polarization test (3.5 wt% NaCl). The surfactants in the electroless nickel bath increases the corrosion resistance properties of the deposit on the magnesium alloy. In addition, smoothness and amorphous plus nano-crystalline phase were increased and accounted for the si...

  2. Effect of Nanoadditives with Surfactant on the Surface Characteristics of Electroless Nickel Coating on Magnesium-Based Composites Reinforced with MWCNT

    OpenAIRE

    Ranganathan Dhinakaran; Rasu Elansezhian; Arunachalam Arumugam Lalitha

    2013-01-01

    An experimental investigation has been carried out on optimizing process parameters of electroless nickel-phosphorous coatings on magnesium composite reinforced with carbon nanotube. A comprehensive experimental study of electroless Ni–P coatings on magnesium composite reinforced with multiwalled carbon nanotube under specific coating conditions was performed. The electroless coating bath consists of nickel sulphate (26 g/L), sodium hypo-phosphite (30 g/L) as reducing agent, sodium acetate (1...

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    Medline Plus

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    Medline Plus

    Full Text Available ... plates! Snap a photo and share it to social media with #CreateYourPlate . See the full gallery of submitted plates! * ... Insurance For Parents & Kids Know Your Rights We Can ...

  5. Surface texturing for adaptive Ag/MoS_2 solid lubricant plating

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    The objective of this research is to prepare specially designed surface texture on hard steel surface by electrochemical micromachining (EM) and to incorporate electroless plated Ag/MoS2 solid lubricant coating into the dimples of EM textured steel surface to effectively reduce friction and wear of steel-steel contacts. The friction and wear behavior of the Ag/MoS2 solid lubricant coating on EM textured steel surface was evaluated in relation to the size and spacing of the dimples thereon. The microstructur...

  6. Controllable Silver Plating on Silica for Surface-enhanced Raman Scattering

    Institute of Scientific and Technical Information of China (English)

    CHEN Lei; HAN Xiao-xia; YANG Jing-xiu; ZHOU Ji; LU Zhi-cheng; SONG Wei; ZHAO Bing; XU Wei-qing; OZAKI Yukihiro

    2011-01-01

    We proposed a facile and rapid method for preparing silica-silver core-shell(SSCS) substrates to use Ag electroless plating on SiO2@Au-seed particles.UV-Vis-NIR absorption spectrometer and SEM were employed to monitor the reaction process of the formation of Ag on the surfaces of silica beads,and the optical resonance of the substrate could shift from visible to NIR region.It has been found that surface-enhanced Raman scattering(SERS)enhancement changes with the electroless plating time and the SSCS substrate with the plating time of 90 s(90SSCS)shows the strongest SERS response under the laser excitation at 514.5 nm.Signals collected over multiple spots and substrate of rhodamine 6G(R6G) resulted in a relative standard deviation(RSD) of 9.75%.The calculated enhancement factor(EF) was approximately 105-106.SSCS substrate exhibits high SERS performance,which is due to electromagnetic SERS enhancement with additional localization field within closely packed Ag nanoparticles decorated on the SiO2 nanoparticles.And this substrate presents tunable and broad localized surface plasmon resonance(LSPR),so this method may open a new way for SERS studies with other laser excitation.

  7. Field emission properties of carbon nanotube cathodes produced using composite plating

    International Nuclear Information System (INIS)

    Field emission properties of carbon nanotube field emission cathodes (CNT-FECs) produced using composite plating are studied. The experiment uses a CNT suspension and electroless Ni plating bath to carry out composite plating. The CNTs were first purified by an acid solution, dispersed in a Ni electrobath, and finally co-deposited with Ni on glass substrates to synthesize electrically conductive films. Field emission scanning electron microscopy and Raman spectroscopy results show that the field emission characteristics and graphitic properties of CNT-FECs depend on the pH value of the electrobath. Experiments show that the optimum electrobath pH value is 5.4, achieving a field emission current density of 1.0 mA/cm2 at an applied electric field of 1.5 V/μm. The proposed CNT-FECs possess good field emission characteristics and have potential for backlight unit application in liquid crystal displays.

  8. Silver-plated carbon nanotubes for silver/conducting polymer composites

    Science.gov (United States)

    Oh, Youngseok; Suh, Daewoo; Kim, Youngjin; Lee, Eungsuek; Mok, Jee Soo; Choi, Jaeboong; Baik, Seunghyun

    2008-12-01

    Carbon nanotubes (CNTs) have advantages as conductive fillers due to their large aspect ratio and excellent conductivity. In this study, a novel silver/conducting polymer composite was developed by the incorporation of silver-plated CNTs. It is important to achieve a homogeneous dispersion of nanotubes and to improve the interfacial bonding to utilize the excellent properties of reinforcements in the matrix material. The homogeneous dispersion of nanotubes was achieved by an acid treatment process, and the interfacial contact was improved by electroless silver plating around nanotubes. The resistivity of the silver/conducting polymer composite was decreased by 83% by the addition of silver-plated single-walled carbon nanotubes. Conductive bumps were also screen-printed to demonstrate the capability of the composite as electrical interconnects for multi-layer printed circuit boards.

  9. Silver-plated carbon nanotubes for silver/conducting polymer composites

    International Nuclear Information System (INIS)

    Carbon nanotubes (CNTs) have advantages as conductive fillers due to their large aspect ratio and excellent conductivity. In this study, a novel silver/conducting polymer composite was developed by the incorporation of silver-plated CNTs. It is important to achieve a homogeneous dispersion of nanotubes and to improve the interfacial bonding to utilize the excellent properties of reinforcements in the matrix material. The homogeneous dispersion of nanotubes was achieved by an acid treatment process, and the interfacial contact was improved by electroless silver plating around nanotubes. The resistivity of the silver/conducting polymer composite was decreased by 83% by the addition of silver-plated single-walled carbon nanotubes. Conductive bumps were also screen-printed to demonstrate the capability of the composite as electrical interconnects for multi-layer printed circuit boards.

  10. Investigation of the magnetization reversal mechanism of electrolessly deposited Co-B nanotubes

    Science.gov (United States)

    Richardson, David; Kingston, Samuel; Rhen, Fernando M. F.

    2016-05-01

    Co-B nanotubes were prepared via an electroless deposition method. The morphology, magnetic properties and the magnetization reversal mechanism of the nanotubes were investigated. Deposition was carried out in porous polycarbonate membranes leading to the formation of Co-B nanotubes with an average external diameter of 400 nm and lengths up to 6 μm. Electroless deposition resulted in the formation of alloys with composition Co70B30 and a specific magnetization of 65.6 J T-1kg-1, which is about 40 % of that of pure Co (161 J T-1kg-1). The transversal and vortex modes were identified as the mechanisms responsible for magnetization reversal in the nanotubes. A crossover between the two modes is observed at low angles and the results are in line with current models for switching mechanisms of nanotubes.

  11. Synthesis of dense nano cobalt-hydroxyapatite by modified electroless deposition technique

    Science.gov (United States)

    Mohd Zaheruddin, K.; Rahmat, A.; Shamsul, J. B.; Mohd Nazree, B. D.; Aimi Noorliyana, H.

    2016-07-01

    Cobalt-hydroxyapatite (Co-HA) composites was successfully prepared by simple electroless deposition process of Co on the surface of hydroxyapatite (HA) particles. Co deposition was carried out in an alkaline bath with sodium hypophosphite as a reducing agent. The electroless process was carried out without sensitization and activation steps. The deposition of Co onto HA was characterized by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). The Co-HA composite powder was compacted and sintered at 1250°C. The Co particles were homogeneously dispersed in the HA matrix after sintering and the mechanical properties of composites was enhanced to 100 % with 3 % wt Co and gradually decreased at higher Co content.

  12. The diamond pyramid structure in electroless copper deposit, its atomic model and molecular dynamics simulation

    International Nuclear Information System (INIS)

    In this paper, we report the discovery of the diamond pyramid structures in the electroless copper deposits on both epoxy and stainless steel substrates. The surface morphology of the structure was characterized with scanning electron microscope (SEM). According to the morphological feature of the structure, an atom model was brought forward in order to describe the possible mechanism of forming such structure. Molecular dynamics (MD) simulations were then carried out to investigate the growing process of the diamond pyramid structure. The final structures of the simulation were compared with the SEM images and the atomic model. The radial distribution function of the final structures of the simulation was compared with that calculated from the X-ray diffraction pattern of the electroless copper deposit sample

  13. The diamond pyramid structure in electroless copper deposit, its atomic model and molecular dynamics simulation

    Science.gov (United States)

    Wu, X.; Sha, W.

    2008-12-01

    In this paper, we report the discovery of the diamond pyramid structures in the electroless copper deposits on both epoxy and stainless steel substrates. The surface morphology of the structure was characterized with scanning electron microscope (SEM). According to the morphological feature of the structure, an atom model was brought forward in order to describe the possible mechanism of forming such structure. Molecular dynamics (MD) simulations were then carried out to investigate the growing process of the diamond pyramid structure. The final structures of the simulation were compared with the SEM images and the atomic model. The radial distribution function of the final structures of the simulation was compared with that calculated from the X-ray diffraction pattern of the electroless copper deposit sample.

  14. Surface-grafted polymer-assisted electroless deposition of metals for flexible and stretchable electronics.

    Science.gov (United States)

    Liu, Xuqing; Zhou, Xuechang; Li, Yi; Zheng, Zijian

    2012-05-01

    Surface-grafted polymers, that is, ultrathin layers of polymer coating covalently tethered to a surface, can serve as a particularly promising nanoplatform for electroless deposition (ELD) of metal thin films and patterned structures. Such polymers consist of a large number of well-defined binding sites for highly efficient and selective uptake of ELD catalysts. Moreover, the polymer chains provide flexible 3D network structures to trap the electrolessly deposited metal particles, leading to strong metal-substrate adhesion. In the past decade, surface-grafted polymers have been demonstrated as efficient nanoplatforms for fabricating durable and high-performance metal coatings by ELD on plastic substrates for applications in flexible and stretchable electronics. This focus review summarizes these recent advances, with a particular focus on applications in polymeric flexible and stretchable substrates. An outlook on the future challenges and opportunities in this field is given at the end of this paper. PMID:22392811

  15. Electroless deposition and characterization of Pd thin films on hydrogenated amorphous silicon

    International Nuclear Information System (INIS)

    This paper reports on electroless palladium thin films deposited on hydrogenated amorphous Si from a palladium-ammine bath. The d.c. magnetron reactive sputtered 18% hydrogenated amorphous silicon (a-Si:H) possessed a hydrogen passivated surface, using an activation step prior to the electroless deposition to obtain a film with good uniformity. The specially prepared hypophosphite-based dilute metal ion bath exhibited good stability as low operating temperatures of 35--50 degrees C. The morphology and microstructure of the Pd aggregates were characterized by scanning transmission electron microscopy (STEM) and energy dispersive x-ray spectroscopy (EDX), while the Pd aggregates and as-deposited films from the citrate and NH3/NH4Cl baths were examined by scanning electron microscopy (SEM). Marked differences in morphology and distribution of the Pd aggregates on activated a-Si:H and c-Si substrates were observed and discussed

  16. Electroless Deposition and Surface-Enhanced Raman Scattering Application of Palladium Thin Films on Glass Substrates

    International Nuclear Information System (INIS)

    In this work, we describe a very simple electroless deposition method to prepare moderate-SERS-active nanostructured Pd films deposited on the glass substrates. To the best of our knowledge, this is the first report on the one-pot electroless method to deposit Pd nanostructures on the glass substrates. This method only requires the incubation of negatively charged glass substrates in ethanol-water mixture solutions of Pd(NO3)2 and butylamine at elevated temperatures. Pd films are then formed exclusively and evenly on glass substrates. Due to the aggregated structures of Pd, the SERS spectra of benzenethiol and organic isonitrile could be clearly identified using the Pd-coated glass as a SERS substrate. This one-step fabrication method of Pd thin film on glass is cost-effective and suitable for the mass production

  17. Area selective formation of magnetic nanodot arrays on Si wafer by electroless deposition

    International Nuclear Information System (INIS)

    Electroless deposition process for fabricating magnetic dot arrays was studied. A patterned Si substrate with a SiO2 resist was produced by processes combined with electron-beam lithography and reactive ion etching. By immersing the patterned Si substrate into a CoNiP electroless deposition bath, CoNiP was deposited only into the patterned pores, demonstrating a satisfactory area selectivity of the deposition. Excellent uniformity on the CoNiP deposition into the patterned pores with diameter less than 100 nm and high aspect ratio (>5) was achieved by applying chemical activation processes using a Pd solution prior to the deposition. The CoNiP dot arrays exhibited higher perpendicular squareness ratio than that of CoNiP continuous film and showed a clear magnetization state at DC-magnetized state, which originated from the shape anisotropy caused by high aspect ratio of the dot patterns

  18. Electroless Deposition and Surface-Enhanced Raman Scattering Application of Palladium Thin Films on Glass Substrates

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Kuan Soo; Cho, Young Kwan [Soongsil Univ., Seoul (Korea, Republic of); Kim, Kyung Lock; Kim, Kwan [Seoul National Univ., Seoul (Korea, Republic of)

    2014-03-15

    In this work, we describe a very simple electroless deposition method to prepare moderate-SERS-active nanostructured Pd films deposited on the glass substrates. To the best of our knowledge, this is the first report on the one-pot electroless method to deposit Pd nanostructures on the glass substrates. This method only requires the incubation of negatively charged glass substrates in ethanol-water mixture solutions of Pd(NO{sub 3}){sub 2} and butylamine at elevated temperatures. Pd films are then formed exclusively and evenly on glass substrates. Due to the aggregated structures of Pd, the SERS spectra of benzenethiol and organic isonitrile could be clearly identified using the Pd-coated glass as a SERS substrate. This one-step fabrication method of Pd thin film on glass is cost-effective and suitable for the mass production.

  19. Selective electroless coating of palladium nanoparticles on metallic single-walled carbon nanotube

    Science.gov (United States)

    Feng, Yiyu; Lv, Peng; Zhang, Xuequan; Li, Yu; Feng, Wei

    2010-08-01

    The selective electroless coating of palladium (Pd) nanoparticles on metallic single-walled carbon nanotube (SWNT) was studied. The remarkable increase in conductivity of SWNT/Pd films up to fourfold higher than pure SWNT was due to p-type doping and Ohmic contact. Metallic behavior of SWNT/Pd-Field effect transistor (on/off ratio=1.2) was attributed to more hole carriers and no electrostatic barrier between nanotube and Pd. G-band and radial breathing mode in Raman indicates a definitive increase in the proportion of metallic SWNT. Results indicate Pd are selectively coated on metallic SWNT with more negative potential allowing for the electroless Pd2+ reduction.

  20. Room temperature synthesis of indium tin oxide nanotubes with high precision wall thickness by electroless deposition

    Directory of Open Access Journals (Sweden)

    Mario Boehme

    2011-02-01

    Full Text Available Conductive nanotubes consisting of indium tin oxide (ITO were fabricated by electroless deposition using ion track etched polycarbonate templates. To produce nanotubes (NTs with thin walls and small surface roughness, the tubes were generated by a multi-step procedure under aqueous conditions. The approach reported below yields open end nanotubes with well defined outer diameter and wall thickness. In the past, zinc oxide films were mostly preferred and were synthesized using electroless deposition based on aqueous solutions. All these methods previously developed, are not adaptable in the case of ITO nanotubes, even with modifications. In the present work, therefore, we investigated the necessary conditions for the growth of ITO-NTs to achieve a wall thickness of around 10 nm. In addition, the effects of pH and reductive concentrations for the formation of ITO-NTs are also discussed.