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The diversity of carrier ions in electrochemical devices has attracted much attention with regard to the use of protons. If the fast proton conduction originating from the Grötthuss mechanism can be utilized, the development of water-based rechargeable batteries that combine safety and rapid charge–discharge performance is expected. However, the narrow potential window of acid-based aqueous solutions limits the operation of active materials. In this work, the effect of the crystal structure on electrochemical protonation/deprotonation of TiO2as a negative electrode material was systematically investigated using slurry-based composite electrodes. In the galvanostatic charge–discharge tests using a buffer electrolyte consisting of 1 M citric acid and 1 M trisodium citrate, the protonation of the rutile TiO2proceeded at a higher potential than those of the anatase and brookite TiO2, resulting in reversible capacities of 102 and 87 mA h g–1at the first cycle and 50th cycle, respectively, due to the decrease in irreversible hydrogen evolution. X-ray diffraction revealed that the protonation occurred inside the bulk, although the changes in the aand caxes during protonation/deprotonation were much smaller than those of Li+and Na+insertion. On the other hand, in particle sizes larger than 100 nm, the hydrogen evolution was dominant and the deprotonation was less in the anatase TiO2, and neither charging/discharging nor even the hydrogen generation occurred in the larger rutile TiO2. This is presumably due to the slow proton diffusion in the solid phases, which stalls the proton storage and induces the reduction of protons at the electrode–electrolyte interface. These obstacles should be overcome by nanosizing the particles and optimizing electrolyte compositions.

Ag-Bi alloy films containing less than 1 mass% Bi were produced using an iodide-tartrate bath without cyanide ions by electrodeposition. Such films could have applications as electrical connectors in quick chargers intended for electric vehicles. The electrodeposition characteristics of these alloys were studied by electrochemical measurements in conjunction with both direct current (DC) and current pulse (CP) plating. The waveform associated with the CP plating incorporated both low and high current densities. The electrodeposition potential of Bi was found to be more negative than that of Ag and the electrodeposition of Bi on Ag was evidently inhibited compared with that on Bi. Aeration increased the limiting current density during electrodeposition of the Ag-Bi alloys. Alloy specimens having powder morphologies could be electrodeposited using the DC plating process while CP plating generated films. Optimization of the waveform gave Ag-Bi alloy films containing less than 1 mass% Bi and having a maximum hardness of 102 HV.

Electrodeposited Ni-11 mass%P alloy plating film was fabricated on the surface of stainless steel SUS304 to conduct brazing of SUS304 plates for a heat exchanger. Brazing of SUS304 plates with electrodeposited Ni-11P layers was carried out using a hydrogen reducing furnace. The microstructure and joint strength of the brazed joint were also investigated. From the result of the microstructural observation of the cross section of the joint, it was found that the brazing filler metal is homogeneously distributed without defects such as voids between the SUS304 plates. The results of electrochemical measurements showed that the P-concentrated phase in the Ni-11P alloy is preferentially dissolved in NaCl aqueous solution.

The development of K-ion batteries composed of abundant elements is a promising way to address the concerns generated by the resource constraint due to the increased demand for Li-ion batteries in the future. The expectation that K-ion batteries can supplement Li-ion batteries originates from the weaker Lewis acidity of K ions than that of Li ions. However, there are limited reports on the kinetics of charge-transfer reactions. Herein, we focused on graphite, which has attracted much attention as a negative-electrode material, and we studied the activation energy of the desolvation of K+at the graphite/electrolyte interface in which the electrolyte typically had a composition of 1 mol kg–1potassium bis(fluorosulfonyl)amide (KFSA) dissolved in ethylene carbonate (EC) and diethyl carbonate (DEC) in a volume ratio of 50:50. Despite the larger solvation number of K+than that of Li+at the same salt concentration, analyzed by Raman spectroscopy measurements, the transference number of K+resulted in a higher value of 0.43 compared to Li+(0.39). The temperature dependence of the charge-transfer resistance associated with K+desolvation using highly oriented pyrolytic graphite as a model electrode, without any binder and conductive additives, was investigated. The activation energy of K+desolvation was found to be approximately 40 kJ mol–1, which is much lower than that of the Li+system. Thus, we experimentally demonstrated that the weaker Lewis acidity of K ions than that of Li ions has the energetically favorable kinetics on the charge-transfer reaction. Moreover, it was found that graphite in composite electrodes undergoes disordering by repeated K+-intercalation/deintercalation. The disordering determined by the initial co-intercalation of the K+-complex followed by the formation of surface layers has a significant relation with cyclability.

The use of high capacity electrode materials based on alloying and dealloying reactions with Na is very effective for improving energy density of batteries. However, their application brings on electrical isolation such as detachment of the electrode mixture layer from a current collector, causing rapid capacity fading. We previously found that Cu electrochemically grows in sheet form by electroplating in a CuSO4-based aqueous solution with poly(acrylic acid) (PAA). In the present study, our goal was to elucidate the formation mechanism of Cu sheets by characterization using scanning transmission electron microscopy (STEM), X-ray diffraction (XRD) analysis, and electron scatter diffraction patterns (EBSD) mapping. Then, the cycling performance of a Sn negative electrode for Na-ion batteries was significantly upgraded by the application of a roughened-Cu substrate with optimized sheet thickness. The STEM images and EBSD maps revealed that the Cu sheet was a single crystal, and the results obtained from XRD and the cathodic polarization behavior of Cu electrodeposition in PAA-containing solutions suggested that PAA molecules adsorbed onto Cu (100) to suppress the Cu growth on the plane, resulting in the formation of Cu sheets. Although the initial reversible capacities of flat-Cu/Sn and roughened-Cu/Sn electrodes were comparable, the developed Cu substrate (1.0 × 10–4M PAA) delivered a noticeable increase in the reversible capacity by 210 mA h g–1from the first to the second cycle, whereas the flat-Cu remained the increase by 100 mA h g–1. In addition, the roughened-Cu substrate suppressed the detachment of the active material layer to maintain a high capacity of 685 mA h g–1with good capacity retention of more than 90% by the anchor effect. These results demonstrate that the roughened-Cu substrate prepared in the present work is a promising candidate as a current collector for rechargeable batteries.

Fe-Ni alloy films with invar alloy compositions were electrodeposited from a stable citrate bath containing trivalent iron ions (Fe3+) as the sole iron source. This bath was prepared based on determining the equilibrium constants for acid dissociation, complex formation and precipitation reactions. Electrodeposition was conducted under galvanostatic conditions at 25 °C without agitation and an investigation was carried out into the effects of pH and current density on the composition and microstructure of the films. The results showed that ferric hydroxide (Fe(OH)3), which is normally poorly soluble, did not precipitate after electrodeposition. Fe-Ni alloy films containing 31‒42 mass% Ni (including Fe-36 mass% Ni) were formed with a current efficiency of approximately 70%. The films were smooth and were made up of grains with sub-micron sizes, although some cracks were observed. Fe and Ni were distributed homogeneously throughout the films and the Fe-Ni solid solutions exhibited both face-centered cubic and body-centered cubic structures.

Copper/single-walled carbon nanotube (SWCNT) composites were fabricated by electrodeposition using a freestanding SWCNT film as a template. The SWCNT films were directly electrodeposited to form copper/SWCNT composites. An acidic copper sulfate bath was employed as a basic plating bath, and the effects of additives to the basic bath on the morphologies of copper deposits were examined. Poly(ethylene glycol), chloride ions (Cl[?]), bis(3-sulfopropyl)disulfide (SPS), and Janus green B (JGB) were added individually or in combination as additives. Electrodeposition of copper occurred only on the surface of the SWCNT film when using the basic plating bath without additives. In contrast, copper was deposited not only on the surface but also in the interior of the SWCNT film when using the plating baths containing at least PEG and Cl[?], resulting in copper/SWCNT composites. Electrodeposition of copper inside the SWCNT film was accelerated dramatically when all four additives (PEG, Cl[?], SPS, and JGB) were added to the basic bath. This novel fabrication method of copper/CNT composites using CNT films as templates can be applied to the fabrication of various types of metal/CNT composites.

The Influence of alkyl chain length in quaternary ammonium cations on electrochemical Zn growth morphology in alkaline-based electrolytes was systematically investigated under constant current density. Mossy structures that typically developed at low current density were mitigated in an electrolyte with 1 mM octyltrimethylammonium chloride. By changing from octyl to decyl group in the surfactant, completely smooth deposition morphology was achieved. Electrochemical impedance spectroscopic analysis revealed that charge transfer resistance associated with Zn deposition increased with alkyl chain length. The obtained results indicate that bulky ammonium cations suppress excess electrodeposition due to the steric hindrance effect and thereby result in smooth morphology.

A three-dimensional (3D) composite film containing copper nanostructures and carbon nanotubes (3DC/CNT composite film) was fabricated by one-step electrodeposition. The 3DC/CNT composite film was formed under galvanostatic conditions using a copper sulfate bath containing CNTs and polyacrylic acid which acts as both a 3DC-forming and a CNT-dispersing agent. The composite film consists of thin copper sheets with thicknesses of ca. 70-80 nm and CNTs, with large interior spaces between sheets. The CNTs were homogeneously distributed inside the composite film and were fixed by the copper sheets where CNTs pierce the copper sheets. The CNT content in the composite films increased with the CNT concentration of the plating bath. The 3DC film without CNTs did not maintain its 3D spaces when the film thickness was increased due to insufficient structural strength, whereas the 3DC/CNT composite film maintained the 3D spaces despite an increase in film thickness, which suggests that the CNTs reinforce the film to maintain the 3D spaces.

Electrochemical intercalation/de-intercalation behavior of Li ion encapsulated by 12-crown-4-ether into/from graphite electrode was studied and compared with a commercially available Li-ion battery electrolyte. In electrolyte solution in which Li ion is coordinated by 12-crown-4-ether, the interlayer of graphite expanded from 0.335 nm to 1.137 nm at charged state of 0.1 V, which is three times larger than that (0.371 nm) in the commercial electrolyte. Charge transfer reaction without desolvation process using Li ion encapsulated by 12-crown-4-ether was successfully progressed even at the high rate of 2C. The insight obtained in this study extend the diversity of carrier ion.

Cu/multiwalled carbon nanotube (MWCNT) composites containing two different sized MWCNTs were fabricated using an electroless deposition technique in aqueous solution. In order to disperse the MWCNTs in the solution, an anionic dispersant of sodium dodecyl sulfate (SDS) and a polymeric dispersant of hydroxypropyl cellulose (HPC) were used. The dispersibility of the MWCNTs in solution was evaluated by measuring the particle size distribution. The zeta potential for the MWCNTs was also evaluated to examine the dispersibility. Uniform Cu/MWCNT composites containing the two different sized MWCNTs were fabricated through the electroless copper deposition process from a solution containing copper ions, a complexing agent, a reducing agent, and two dispersants, SDS and HPC, in addition to the two different sized MWCNTs.

Micro-scale columnar architectures composed of copper sheets with nanometer thickness were fabricated by electrodeposition using a photolithography technique. A copper sulfate solution containing a polyacrylic acid was used as the plating bath, and the electrodeposition was conducted under galvanostatic conditions. Patterned electrodeposits with a cylindrical shape and composed of thin copper sheets were formed. Every copper deposit had openings on the top and side regions and also had a porous interior. This novel three-dimensional (3D) copper architecture should provide functional copper electrodes with large effective surface areas.

Composite films containing copper and multiwalled carbon nanotubes (MWCNTs) with different dimensions were fabricated by electroless deposition and their microstructure and frictional properties were evaluated. The films were formed using an electroless copper plating bath including dispersants of sodium lauryl sulfate and hydroxypropyl cellulose for MWCNTs. The microstructure of the films was characterized by scanning electron microscopy and X-ray diffraction, and their frictional properties were investigated using a ball-on-disk method without a lubricant. All of the deposited films contained uniformly dispersed MWCNTs, and exhibited significantly lower coefficients of friction than copper films.

Co-W alloy/multiwalled carbon nanotube (MWCNT) composite films were fabricated using an electrodeposition technique and their microstructures were characterized. A citrate bath was used as the Co-W alloy/MWCNT composite plating bath. A compact Co-W alloy/MWCNT composite film having uniform distribution of MWCNTs without cracks was electrodeposited by adjusting the pH and current density. Frictional properties of the Co-W alloy/MWCNT composite film were evaluated using a ball-on-disk method at room temperature as well as at elevated temperatures ([?] 300degC) without any lubricant. The coefficient of friction of the Co-W alloy/MWCNT composite film was clearly lower than that of a Co-W alloy film with the same tungsten content at room temperature. The coefficient of friction of the Co-W alloy/MWCNT composite film increased with increasing temperature. However, the coefficient of friction of the Co-W alloy/MWCNT composite film was lower than that of a Co-W alloy film with the same tungsten content at elevated temperatures.

The mechanism involved in the codeposition of carbon nanotubes (CNTs) with copper from an acid copper sulfate bath was investigated. Multiwalled carbon nanotubes (MWCNTs) were employed and dispersed using polyacrylic acid. To determine the influence of the fibrous shape of the MWCNTs, codeposition was also carried out using copper and granular carbon black (CB). The effect of the polyacrylic acid on the dispersibility of MWCNTs and CB in the plating baths and the electrodeposition behavior of copper was investigated. In addition, the relationship between the initial MWCNT or CB concentration in the plating bath and that in the composite films was evaluated and the results are discussed based on the two-step adsorption model of Guglielmi. It was found that although for low MWCNT concentrations in the plating bath, this model could adequately explain the codeposition behavior, at higher concentrations, the MWCNT content in the deposit was larger than expected. It is suggested that the increased MWCNT content is related to the fibrous shape of the MWCNTs.

Electroless deposition of silver on multiwalled carbon nanotubes (MWCNTs) was investigated using an iodide bath. Prior to electroless deposition of silver, the MWCNTs were chemically oxidized and then pre-treated using a typical two-step method (sensitization and activation) to form catalytic palladium nuclei on the MWCNTs. Dimethylaminoborane (DMAB) was used to reduce silver ions. Electroless deposition of silver was carried out at 25degC with variation of the pH. The microstructure of the deposits was evaluated using field emission-scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), and transmission electron microscopy (TEM). The silver iodide complex ion species present was determined to be AgI4 3[?] from equilibrium potential measurements. Silver was selectively deposited on palladium nuclei on the surface of the MWCNTs and continuous diffusion of deposited silver and palladium nuclei resulted in a solid solution of Ag-Pd alloy particles on the MWCNTs at pH = 7.5.

Cu/multiwalled carbon nanotube (MWCNT) composite plating by a pulse-reverse (PR) electrodeposition method was investigated in order to increase the MWCNT content of the composite plating films. The electrodeposition and dissolution behaviors of the composite films were investigated using scanning electron microscopy and X-ray diffraction to determine the most suitable electrodeposition and dissolution current densities for PR electrodeposition. PR electrodeposition of the Cu/MWCNT composite films was conducted by varying the current reverse ratios at the most suitable electrodeposition and dissolution current densities. The surface morphology of the Cu/MWCNT composite films after dissolution was significantly changed by variation of the anodic current densities. The MWCNT content of the composite films formed by PR electrodeposition was greater than that obtained using a direct current (dc) electrodeposition method, and reached a maximum value of , which is a 40% increase over that for dc electrodeposition. Furthermore, the surface roughness of the composite films fabricated by PR electrodeposition was less than that by dc electrodeposition.

Ni-P alloy/multiwalled carbon nanotube (MWCNT) composite films were fabricated using an electroless plating method, and their microstructures and frictional properties were studied. MWCNTs of various sizes were used and three kinds of electroless plating baths were prepared to form the Ni-P alloy matrix with varying phosphorus contents. Heat-treatments of the composite films were also carried out. The microstructures of the composite films were examined by scanning electron microscopy and X-ray diffraction. Frictional properties of the composite films were investigated using a ball-on-plate method. Ni-P alloy/MWCNT composite films with different phosphorus contents, classified as high phosphorus (12-13 mass %), medium phosphorus (6-8 mass %), and low phosphorus (2-4 mass %) types, were fabricated using electroless deposition. The Ni-P alloy/MWCNT composite films showed lower friction coefficients compared to Ni-P alloy films with the same phosphorus content both before and after heat-treatment. The friction coefficients of the films were affected by the microstructure and size of the MWCNTs, the composition of the Ni-P alloy matrix, and the heat-treatment.

Copper-multiwalled carbon nanotube (MWCNT) composite plating using a sulfuric base bath was studied. A dispersing agent was used to disperse the MWCNTs into the plating bath. The effects of electrodeposition conditions on the surface morphology, microstructure, and MWCNT content in the composite films were examined. The internal stress, hardness, electrical conductivity, and thermal conductivity of the composite films were also investigated. The current density remarkably affected the surface morphologies of the films, and a relatively smooth surface was obtained at lower current densities. The bath temperature affected the microstructure of the composite films; a compact microstructure was formed at a lower temperature. The MWCNT content in the composite film increased with increasing MWCNT concentration in the plating bath, reaching a maximum value of 0.55 mass %. However, MWCNTs in the composite films tended to agglomerate for high MWCNT concentrations in the plating bath. An internal tensile stress was induced in the films. The hardness of the films was around 150 HV, and the electrical resistivity was approximately . The thermal conductivity of the Cu-0.42 mass % MWCNT composite film was .

The effects of plating bath additives on copper-multiwalled carbon nanotube (MWCNT) composite platings were studied. An acidified cupric sulfate electrolyte containing MWCNTs and polyacrylic acid as a dispersing agent was used as the base plating bath. Chloride ions , poly(ethylene glycol), bis(3-sulfopropyl)disulfide (SPS), and Janus green B (JGB) were examined as additives. The surface morphologies and cross-sectional microstructures of the electrodeposited films were investigated, and the MWCNT content of the films was determined. Furthermore, the electrical resistivity and field emission properties of the films were evaluated. The simultaneous addition of , SPS, and JGB to the base plating bath was effective for forming smooth Cu-MWCNT composite films with a high MWCNT content over a wider range of current densities. The optimal bath composition was 0.85 mol SPS + 2 ppm JGB +50 ppm Cl[?]. Cu-MWCNT composite films containing 0.15-0.33 mass % MWCNTs with smooth surface morphologies were formed in the current density range of . The electrical resistivity of the films was around , and they showed obvious field emission properties.

Ni-B alloy films containing amorphous boron particles (referred to as "Ni-B alloy composite films") were fabricated by electrodeposition and were subsequently subjected to heat-treatment. Their compositions and microstructures were characterized, and their hardness was evaluated. The content of boron particles in the alloy composite films increased with boron particle concentration in the plating baths. In addition, the total boron content in the films increased with decreasing current density, reaching a maximum value of 34.3 atom %. The boron particles were homogeneously distributed in these alloy composite films and exhibited no cohesion. Heat-treatment of the alloy composite films consisting of a Ni-B alloy matrix and the boron particles led to a phase conversion from an inhomogeneous amorphous phase to stable homogeneous crystalline phases, which were similar to those in the Ni-B binary alloy phase diagram. The hardness of the Ni-B alloy 34.3 atom % B composite film was higher than that of a Ni-B alloy film both before and after heat-treatment.

Ni-P alloy-multiwalled carbon nanotube (MWCNT) composite films were fabricated by an electrodeposition technique, and their microstructure, hardness, and frictional properties were analyzed. Ni-P alloy-MWCNT composite films containing 20-22 atom % P and 0.7-1.2 mass % MWCNTs were electrodeposited from a composite plating bath. MWCNTs were embedded relatively uniformly in the Ni-P alloy matrix. The hardness of the composite films was higher than that of the Ni-P alloy films, both before and after heat-treatment, and the friction coefficient of the composite films was lower than that of the Ni-P alloy films.

A three-dimensional copper nanostructure architecture (3DC1) coated uniformly with a tin film was fabricated by electrodeposition. In these trials, a pyrophosphate bath was used for tin plating, and the effects of polyethylene glycol and formaldehyde additives on the morphology of the deposited tin were investigated. Relatively large tin particles were electrodeposited in an inhomogeneous manner over the 3DC1 surface when using a plating bath without additives. In contrast, 3DC1 coated with a uniformly thick tin film was fabricated by employing a bath with the additives.

Ni-P alloy films containing phosphorus particles (called "Ni-P alloy composite films") were fabricated by electrodeposition and were subsequently subjected to heat-treatment. Their compositions and microstructures were characterized, and their friction properties were evaluated using a ball-on-plate method. Composite electroplating in the nickel sulfate and chloride bath containing phosphorus acid and micrometer-sized phosphorus particles resulted in the Ni-P alloy coating with enhanced deposit phosphorus content. The phosphorus content of the films increased with increasing phosphorus particle concentration in the composite plating baths, reaching a maximum value of 29.0 atom %. The phosphorus particles were homogeneously distributed in this Ni-29.0 atom % P alloy composite film. Heat-treatment converted the phases of the alloy composite films from an amorphous phase to stable crystalline phases, which are the same as those in the Ni-P binary alloy phase diagram. The friction coefficients of the Ni-P alloy films increased with increasing cycle number, whereas those of the Ni-P alloy composite films remained relatively constant. The alloy composite films had lower friction coefficients than the Ni-P alloy films both before and after heat-treatment. These results indicate that phosphorus particles are beneficial for maintaining a lower and stable friction coefficient during the ball-on-plate reciprocating friction test.

A Cu brazing sheet has been developed using a Cu-P composite plating method. A Cu-P composite plating layer, which contains 7mass%P, was formed on a Cu plate with a copper sulfate solution including P particles. The melting start temperature of the Cu-P composite layer was determined to be approximately 765°C. Microstructure and joint strength of a brazed joint with the Cu-P composite layer were investigated and compared with those of the joint with a conventional Cu-7P filler foil. As the results of the study, it was clarified that the Cu-P composite layer developed is feasible to use as a brazing material for Cu and Cu alloys.

Three-dimensional (3D) copper nanostructured architectures were fabricated on a copper substrate using a simple electrodeposition technique. An acid copper sulfate bath was used for copper plating with polyacrylic acid (PA) as an additive and electrodeposition was performed under galvanostatic conditions. The surface morphology of the electrodeposited copper films was significantly changed and a 3D nanostructured architecture that consisted of highly porous 50 nm thick sheet-like copper deposits was obtained by the addition of PA. It is considered that such a 3D nanostructured architecture could be applied as a current collector for lithium-ion battery anodes.

Pure-nickel-coated multiwalled carbon nanotubes (MWCNTs) have been prepared by electroless deposition. Gluconic acid and hydrazine were respectively used as the complexing and reducing agents for nickel ions. The deposits were heat-treated. The microstructures and magnetic properties of the deposits were examined. The MWCNTs were homogeneously coated with pure nickel and their surfaces were relatively bumpy. These pure-nickel-coated MWCNTs exhibited ferromagnetism and had higher magnetizations and coercivities than electroless Ni-P alloy-coated MWCNTs. The bumpy morphology of the pure-nickel coating became relatively smooth on heat-treatment.

We have demonstrated that patterned Cu-multiwalled carbon nanotube (MWCNT) composite emitters can be fabricated using a unique electrodeposition technique including a photolithography process. Well-regulated, patterned Cu-MWCNT composite emitters in diameter were formed on the conductive substrates. The MWCNTs were fixed on the patterned composite emitters. The field emission properties were studied by a diode-type measurement system. The field emission electric field was relatively low ( for , for ). These composite emitters can be expected to be applied in field emission displays and other field emission devices.

Ag/carbon nanotube (CNT) composite films were prepared by electrodeposition from non-cyanide baths. An iodide bath and multiwalled CNTs were used. The stability of the iodide bath under ambient conditions at various pH levels was examined, along with the changes in visual appearance, pH, and triiodide ion (I3?) concentration. The electrodeposition was conducted under galvanostatic conditions using iodide baths with and without CNTs. The microstructure of the Ag and Ag/CNT composite films was characterized, and the hardness, electrical conductivity, and coefficient of friction of the films were measured. The iodide bath was stable at higher pH levels under ambient conditions. The obtained Ag/CNT composite films exhibited a compact structure, and CNTs were homogeneously distributed in the interior of the deposited Ag matrix. The CNT content in the deposits increased with increasing CNT concentration in the plating bath. The hardness of the Ag/1.2 mass%-CNT composite film was 63.2 HV, which was slightly greater than that of the Ag film (60.4 HV). The resistivity of the composite film was 1.9 ?? cm, which was slightly higher than that of the pure Ag film (1.8 ?? cm). The coefficient of friction of the composite film was lower than that of the Ag film.

• A study was devised to test for Carp's agent in the sera of Japanese patients with multiple sclerosis (MS). The sera were obtained from 17 patients with definite MS and six patients with possible MS. Strain C3H mice were given an intraperitoneal injection of 0.1 mL of each serum. One week before and 1, 3, and 6 weeks after inoculation, blood drops from tail tip were smeared and polymorphonuclear leukocytes (PMNLs) were counted. Although the experimental animals were kept under careful control, substantial fluctuation in the number of PMNL occurred, and the variations of PMNL count in the experimental groups were all within the normal range. We conclude that there is no Carp's agent in the sera of patients with MS in Japan.

The Influence of alkyl chain length in quaternary ammonium cations on electrochemical Zn growth morphology in alkaline-based electrolytes was systematically investigated under constant current density. Mossy structures that typically developed at low current density were mitigated in an electrolyte with 1 mM octyltrimethylammonium chloride. By changing from octyl to decyl group in the surfactant, completely smooth deposition morphology was achieved. Electrochemical impedance spectroscopic analysis revealed that charge transfer resistance associated with Zn deposition increased with alkyl chain length. The obtained results indicate that bulky ammonium cations suppress excess electrodeposition due to the steric hindrance effect and thereby result in smooth morphology.

Electrochemical intercalation/de-intercalation behavior of Li ion encapsulated by 12-crown-4-ether into/from graphite electrode was studied and compared with a commercially available Li-ion battery electrolyte. In electrolyte solution in which Li ion is coordinated by 12-crown-4-ether, the interlayer of graphite expanded from 0.335 nm to 1.137 nm at charged state of 0.1 V, which is three times larger than that (0.371 nm) in the commercial electrolyte. Charge transfer reaction without desolvation process using Li ion encapsulated by 12-crown-4-ether was successfully progressed even at the high rate of 2C. The insight obtained in this study extend the diversity of carrier ion.

Micro-scale columnar architectures composed of copper sheets with nanometer thickness were fabricated by electrodeposition using a photolithography technique. A copper sulfate solution containing a polyacrylic acid was used as the plating bath, and the electrodeposition was conducted under galvanostatic conditions. Patterned electrodeposits with a cylindrical shape and composed of thin copper sheets were formed. Every copper deposit had openings on the top and side regions and also had a porous interior. This novel three-dimensional (3D) copper architecture should provide functional copper electrodes with large effective surface areas.

Copper/single-walled carbon nanotube (SWCNT) composites were fabricated by electrodeposition using a freestanding SWCNT film as a template. The SWCNT films were directly electrodeposited to form copper/SWCNT composites. An acidic copper sulfate bath was employed as a basic plating bath, and the effects of additives to the basic bath on the morphologies of copper deposits were examined. Poly(ethylene glycol), chloride ions (Cl−), bis(3-sulfopropyl)disulfide (SPS), and Janus green B (JGB) were added individually or in combination as additives. Electrodeposition of copper occurred only on the surface of the SWCNT film when using the basic plating bath without additives. In contrast, copper was deposited not only on the surface but also in the interior of the SWCNT film when using the plating baths containing at least PEG and Cl−, resulting in copper/SWCNT composites. Electrodeposition of copper inside the SWCNT film was accelerated dramatically when all four additives (PEG, Cl−, SPS, and JGB) were added to the basic bath. This novel fabrication method of copper/CNT composites using CNT films as templates can be applied to the fabrication of various types of metal/CNT composites.

A three-dimensional copper nanostructure architecture (3DC1) coated uniformly with a tin film was fabricated by electrodeposition. In these trials, a pyrophosphate bath was used for tin plating, and the effects of polyethylene glycol and formaldehyde additives on the morphology of the deposited tin were investigated. Relatively large tin particles were electrodeposited in an inhomogeneous manner over the 3DC1 surface when using a plating bath without additives. In contrast, 3DC1 coated with a uniformly thick tin film was fabricated by employing a bath with the additives.

A three-dimensional (3D) composite film containing copper nanostructures and carbon nanotubes (3DC/CNT composite film) was fabricated by one-step electrodeposition. The 3DC/CNT composite film was formed under galvanostatic conditions using a copper sulfate bath containing CNTs and polyacrylic acid which acts as both a 3DC-forming and a CNT-dispersing agent. The composite film consists of thin copper sheets with thicknesses of ca. 70–80 nm and CNTs, with large interior spaces between sheets. The CNTs were homogeneously distributed inside the composite film and were fixed by the copper sheets where CNTs pierce the copper sheets. The CNT content in the composite films increased with the CNT concentration of the plating bath. The 3DC film without CNTs did not maintain its 3D spaces when the film thickness was increased due to insufficient structural strength, whereas the 3DC/CNT composite film maintained the 3D spaces despite an increase in film thickness, which suggests that the CNTs reinforce the film to maintain the 3D spaces.

Cu/multiwalled carbon nanotube (MWCNT) composites containing two different sized MWCNTs were fabricated using an electroless deposition technique in aqueous solution. In order to disperse the MWCNTs in the solution, an anionic dispersant of sodium dodecyl sulfate (SDS) and a polymeric dispersant of hydroxypropyl cellulose (HPC) were used. The dispersibility of the MWCNTs in solution was evaluated by measuring the particle size distribution. The zeta potential for the MWCNTs was also evaluated to examine the dispersibility. Uniform Cu/MWCNT composites containing the two different sized MWCNTs were fabricated through the electroless copper deposition process from a solution containing copper ions, a complexing agent, a reducing agent, and two dispersants, SDS and HPC, in addition to the two different sized MWCNTs.

trans-2-Cycloocten-1-one and trans-2-cyclohepten-1-one, which are supposed to be formed by the ultra-violet irradiation of cis-2-cycloocten-1-one and cis-2-cyclohepten-1-one, give Diels-Alder addition products with cyclopentadiene and isoprene.

Composite films containing copper and multiwalled carbon nanotubes (MWCNTs) with different dimensions were fabricated by electroless deposition and their microstructure and frictional properties were evaluated. The films were formed using an electroless copper plating bath including dispersants of sodium lauryl sulfate and hydroxypropyl cellulose for MWCNTs. The microstructure of the films was characterized by scanning electron microscopy and X-ray diffraction, and their frictional properties were investigated using a ball-on-disk method without a lubricant. All of the deposited films contained uniformly dispersed MWCNTs, and exhibited significantly lower coefficients of friction than copper films.

Three-dimensional (3D) copper nanostructured architectures were fabricated on a copper substrate using a simple electrodeposition technique. An acid copper sulfate bath was used for copper plating with polyacrylic acid (PA) as an additive and electrodeposition was performed under galvanostatic conditions. The surface morphology of the electrodeposited copper films was significantly changed and a 3D nanostructured architecture that consisted of highly porous 50 nm thick sheet-like copper deposits was obtained by the addition of PA. It is considered that such a 3D nanostructured architecture could be applied as a current collector for lithium-ion battery anodes.

The mechanism involved in the codeposition of carbon nanotubes (CNTs) with copper from an acid copper sulfate bath was investigated. Multiwalled carbon nanotubes (MWCNTs) were employed and dispersed using polyacrylic acid. To determine the influence of the fibrous shape of the MWCNTs, codeposition was also carried out using copper and granular carbon black (CB). The effect of the polyacrylic acid on the dispersibility of MWCNTs and CB in the plating baths and the electrodeposition behavior of copper was investigated. In addition, the relationship between the initial MWCNT or CB concentration in the plating bath and that in the composite films was evaluated and the results are discussed based on the two-step adsorption model of Guglielmi. It was found that although for low MWCNT concentrations in the plating bath, this model could adequately explain the codeposition behavior, at higher concentrations, the MWCNT content in the deposit was larger than expected. It is suggested that the increased MWCNT content is related to the fibrous shape of the MWCNTs.

Co-W alloy/multiwalled carbon nanotube (MWCNT) composite films were fabricated using an electrodeposition technique and their microstructures were characterized. A citrate bath was used as the Co-W alloy/MWCNT composite plating bath. A compact Co-W alloy/MWCNT composite film having uniform distribution of MWCNTs without cracks was electrodeposited by adjusting the pH and current density. Frictional properties of the Co-W alloy/MWCNT composite film were evaluated using a ball-on-disk method at room temperature as well as at elevated temperatures (∼ 300°C) without any lubricant. The coefficient of friction of the Co-W alloy/MWCNT composite film was clearly lower than that of a Co-W alloy film with the same tungsten content at room temperature. The coefficient of friction of the Co-W alloy/MWCNT composite film increased with increasing temperature. However, the coefficient of friction of the Co-W alloy/MWCNT composite film was lower than that of a Co-W alloy film with the same tungsten content at elevated temperatures.

Electroless deposition of silver on multiwalled carbon nanotubes (MWCNTs) was investigated using an iodide bath. Prior to electroless deposition of silver, the MWCNTs were chemically oxidized and then pre-treated using a typical two-step method (sensitization and activation) to form catalytic palladium nuclei on the MWCNTs. Dimethylaminoborane (DMAB) was used to reduce silver ions. Electroless deposition of silver was carried out at 25°C with variation of the pH. The microstructure of the deposits was evaluated using field emission-scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), and transmission electron microscopy (TEM). The silver iodide complex ion species present was determined to be AgI43−from equilibrium potential measurements. Silver was selectively deposited on palladium nuclei on the surface of the MWCNTs and continuous diffusion of deposited silver and palladium nuclei resulted in a solid solution of Ag-Pd alloy particles on the MWCNTs at pH = 7.5.

Cu/multiwalled carbon nanotube (MWCNT) composite plating by a pulse-reverse (PR) electrodeposition method was investigated in order to increase the MWCNT content of the composite plating films. The electrodeposition and dissolution behaviors of the composite films were investigated using scanning electron microscopy and X-ray diffraction to determine the most suitable electrodeposition and dissolution current densities for PR electrodeposition. PR electrodeposition of the Cu/MWCNT composite films was conducted by varying the current reverse ratios at the most suitable electrodeposition and dissolution current densities. The surface morphology of the Cu/MWCNT composite films after dissolution was significantly changed by variation of the anodic current densities. The MWCNT content of the composite films formed by PR electrodeposition was greater than that obtained using a direct current (dc) electrodeposition method, and reached a maximum value of 0.59mass%, which is a 40% increase over that for dc electrodeposition. Furthermore, the surface roughness of the composite films fabricated by PR electrodeposition was less than that by dc electrodeposition.

Pure-nickel-coated multiwalled carbon nanotubes (MWCNTs) have been prepared by electroless deposition. Gluconic acid and hydrazine were respectively used as the complexing and reducing agents for nickel ions. The deposits were heat-treated. The microstructures and magnetic properties of the deposits were examined. The MWCNTs were homogeneously coated with pure nickel and their surfaces were relatively bumpy. These pure-nickel-coated MWCNTs exhibited ferromagnetism and had higher magnetizations and coercivities than electroless Ni–P alloy-coated MWCNTs. The bumpy morphology of the pure-nickel coating became relatively smooth on heat-treatment.

Ni–P alloy/multiwalled carbon nanotube (MWCNT) composite films were fabricated using an electroless plating method, and their microstructures and frictional properties were studied. MWCNTs of various sizes were used and three kinds of electroless plating baths were prepared to form the Ni–P alloy matrix with varying phosphorus contents. Heat-treatments of the composite films were also carried out. The microstructures of the composite films were examined by scanning electron microscopy and X-ray diffraction. Frictional properties of the composite films were investigated using a ball-on-plate method. Ni–P alloy/MWCNT composite films with different phosphorus contents, classified as high phosphorus (12–13 mass %), medium phosphorus (6–8 mass %), and low phosphorus (2–4 mass %) types, were fabricated using electroless deposition. The Ni–P alloy/MWCNT composite films showed lower friction coefficients compared to Ni–P alloy films with the same phosphorus content both before and after heat-treatment. The friction coefficients of the films were affected by the microstructure and size of the MWCNTs, the composition of the Ni–P alloy matrix, and the heat-treatment.

We fabricated silver-carbon nanotube (Ag-CNT) composite plating films and prepared samples after a H2S gas corrosion test. After corrosion, although the elastic modulus of Ag film increased 1.9 times, there was no marked difference in the mechanical characteristic of Ag-CNT film. At a low load, for the Ag-CNT film after corrosion, there was no polarity and the contact resistance was low and ohmic, although the contact resistance of Ag film after corrosion was high and polar. Therefore, Ag-CNT film can be considered as a promising material for next-generation electrical contact applications.

We fabricated silver-carbon nanotube (Ag-CNT) composite plating films and prepared samples after a H2S gas corrosion test. After corrosion, although the elastic modulus of Ag film increased 1.9 times, there was no marked difference in the mechanical characteristic of Ag-CNT film. At a low load, for the Ag-CNT film after corrosion, there was no polarity and the contact resistance was low and ohmic, although the contact resistance of Ag film after corrosion was high and polar. Therefore, Ag-CNT film can be considered as a promising material for next-generation electrical contact applications.

Copper–multiwalled carbon nanotube (MWCNT) composite plating using a sulfuric base bath was studied. A dispersing agent was used to disperse the MWCNTs into the plating bath. The effects of electrodeposition conditions on the surface morphology, microstructure, and MWCNT content in the composite films were examined. The internal stress, hardness, electrical conductivity, and thermal conductivity of the composite films were also investigated. The current density remarkably affected the surface morphologies of the films, and a relatively smooth surface was obtained at lower current densities. The bath temperature affected the microstructure of the composite films; a compact microstructure was formed at a lower temperature. The MWCNT content in the composite film increased with increasing MWCNT concentration in the plating bath, reaching a maximum value of 0.55 mass %. However, MWCNTs in the composite films tended to agglomerate for high MWCNT concentrations in the plating bath. An internal tensile stress was induced in the films. The hardness of the films was around 150 HV, and the electrical resistivity was approximately 2–2.5μΩcm. The thermal conductivity of the Cu–0.42 mass % MWCNT composite film was 355Wm−1K−1.