ULVAC RIKO Inc.

Yokohama-shi, Japan

ULVAC RIKO Inc.

Yokohama-shi, Japan
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Agawa Y.,ULVAC RIKO Inc. | Endo S.,ULVAC RIKO Inc. | Matsuura M.,ULVAC RIKO Inc. | Ishii Y.,ULVAC RIKO Inc.
ECS Transactions | Year: 2012

We have proposed a new platinum catalyst supporting method using a nanoparticle forming pulsed arc plasma source. This supporting method has the following features: 1. Distribution of nanoparticle diameter is small; 2. Nanoparticle diameter can be easily controlled by changing discharge parameters; 3. Nanoparticle diameter can be kept constant while its deposition rate is changed; 4. Since nanoparticles are adhered to the surface of the supporting material strongly, aggregation of the catalysts can be suppressed even at high temperature. Platinum catalyst on carbon powder for polymer electrolyte fuel cell electrodes was prepared using this method and current / voltage characteristic of its MEA was evaluated. Although its performance is a little inferior compared to the conventional catalyst prepared by wet chemistry, it may be concluded that a good characteristic is acquired considering only 1/10 th the amount of platinum was used. © The Electrochemical Society.


Ito T.,Kanagawa Industrial Technology Center | Kunimatsu M.,Kanagawa Industrial Technology Center | Kaneko S.,Kanagawa Industrial Technology Center | Hirabayashi Y.,Kanagawa Industrial Technology Center | And 3 more authors.
Talanta | Year: 2012

We propose novel electrodes with platinum nanoparticles dispersed on a glassy carbon (Pt-NPs/GC) prepared using a pulsed arc plasma deposition (APD) method. The method could coat Pt-NPs on a base material directly with a single-step process in a very short deposition time. The characteristics of the electrodes were discussed in detail. The detection of hydrogen peroxide was performed as an example for application of the electrodes. The distribution of nanoparticles was controlled easily by the number of pulse. The surface morphology changed with the pulse number and the annealing except for the sample prepared by 5 pulses deposition (APD(5)), implying that the APD(5) remained as NPs after the annealing. Average particle size was 2.7 nm on the Pt-NPs/GC. Catalyst activity for oxidizing hydrogen peroxide per Pt loading was excellent on the Pt-NPs/GC. When the Pt-NPs/GC was used as a detector for hydrogen peroxide on a flow injection analysis, the Pt-NPs/GC showed high sensitivity without deterioration. Oxidation current increased linearly with the concentration of hydrogen peroxide from 10 nM to 100 μM. This fast and easily prepared electrode showed the capability to replace a conventional bulk metal electrode. © 2012 Elsevier B.V.


Agawa Y.,ULVAC RIKO Inc. | Endo S.,ULVAC RIKO Inc. | Matsuura M.,ULVAC RIKO Inc. | Ishii Y.,ULVAC RIKO Inc.
Advanced Materials Research | Year: 2010

By the use of a coaxial pulsed vacuum arc discharge deposition method (APD), we have developed the catalyst deposition system onto support powders or sheet under vacuum. In this letter, we introduce Pt catalysis processing for fuel cell and evaluation for the electrode property. © (2010) Trans Tech Publications.


Nakamura Y.,Osaka University | Nakamura Y.,Japan Science and Technology Agency | Isogawa M.,Osaka University | Ueda T.,Osaka University | And 9 more authors.
Nano Energy | Year: 2015

Reduction of thermal conductivity κ while preserving high electrical conductivity σ in materials continues to be a vital goal in thermoelectric study for the reuse of exhaust heat energy. In the use of an eco-friendly and ubiquitous element, Si as thermoelectric material, high κ value in bulk Si is the essential bottleneck to achieve high dimensionless figure of merit. This is a motivation for many recent studies on reducing κ in Si, by nanostructuring, e.g., using grains/wires with size smaller than the phonon mean free path. However, κ reduction that can be achieved tends to be saturated presumably due to an amorphous limit. Here, we present a nanoarchitecture for defeating the κ amorphous limit while preserving bulk-like σ. This new nanoarchitecture is an assembly of Si nanocrystals with oriented crystals separated by a 1-monolayer amorphous layer with well-controlled nanoscale shaped interfaces. At these interfaces, novel phonon scattering occurs resulting in κ reduction below the amorphous limit. Preservation of bulk-like σ results from the coherency of the carrier wavefunctions among the oriented nanocrystals separated by the ultrathin amorphous layer. The results will bring environmentally-friendly and low-cost thermoelectric Si material compatible with mature LSI process technology and represent guidelines for optimized thermoelectric nanostructures. © 2014 Elsevier Ltd.


Agawa Y.,ULVAC RIKO Inc. | Tanaka H.,ULVAC RIKO Inc. | Torisu S.,ULVAC RIKO Inc. | Endo S.,ULVAC RIKO Inc. | And 9 more authors.
Science and Technology of Advanced Materials | Year: 2015

We have developed a new method of preparing Pt electrocatalysts through a dry process. By coaxial pulse arc plasma deposition (CAPD), highly ionized metal plasma can be generated from a target rod without any discharged gases, and Pt nanoparticles can be deposited on a carbon support. The small-sized Pt nanoparticles are distributed over the entire carbon surface. From transmission electron microscopy (TEM), the average size of the deposited Pt nanoparticles is estimated to be 2.5 nm, and their size distribution is narrow. Our electrocatalyst shows considerably improved catalytic activity and stability toward methanol oxidation reaction (MOR) compared with commercially available Pt catalysts such as Pt black and Pt/carbon (PtC). Inspired by its very high efficiency toward MOR, we also measured the catalytic performance for oxygen reduction reaction (ORR). Our PtC catalyst shows a better performance with half-wave potential of 0.87 V, which is higher than those of commercially available Pt catalysts. The higher performance is also supported by a right-shifted onset potential. Our preparation is simple and could be applied to other metallic nanocrystals as a novel platform in catalysis, fuel cells and biosensors. © 2015 National Institute for Materials Science.


Kuwahara M.,Japan National Institute of Advanced Industrial Science and Technology | Suzuki O.,Japan National Institute of Advanced Industrial Science and Technology | Suzuki O.,ULVAC RIKO Inc. | Yagi T.,Japan National Institute of Advanced Industrial Science and Technology | Taketoshi N.,Japan National Institute of Advanced Industrial Science and Technology
Japanese Journal of Applied Physics | Year: 2013

We have measured the temperature dependence of the complex refractive index, specific heat capacity, and thermal conductivity of crystalline Sb-Te alloys and ZnS-SiO2 with various compositions by using a spectroscopic ellipsometer, differential scanning calorimeter, and nanosecond pulsed light heating thermoreflectance system. The temperature range was set from room temperature to several hundred degrees Celsius. The values of these properties are useful for calculating realistic temperatures in memory devices and for designing device structures. © 2013 The Japan Society of Applied Physics.


Agawa Y.,ULVAC RIKO Inc. | Endo S.,ULVAC RIKO Inc. | Matsuura M.,ULVAC RIKO Inc. | Ishii Y.,ULVAC RIKO Inc.
Proceedings of the IEEE Conference on Nanotechnology | Year: 2011

By the use of a coaxial pulsed vacuum arc discharge deposition method (APD), we have developed a catalyst deposition system for support powders or sheet materials under vacuum. In this poster, we introduce Pt catalysis processing for fuel cells and evaluation of the resulting electrical properties. © 2011 IEEE.


Akoshima M.,National Metrology Institute of Japan | Tanaka T.,Sumitomo Metal Technology Inc. | Endo S.,Ulvac Riko Inc. | Tetsuya Baba,National Metrology Institute of Japan | And 4 more authors.
Japanese Journal of Applied Physics | Year: 2011

Ceramic-based thermal barrier coatings are used as heat and wear shields of gas turbine blades. There is a strong need to evaluate the thermal conductivity of coating for thermal design and use. The thermal conductivity of a bulk material is obtained as the product of thermal diffusivity, specific heat capacity, and density above room temperature in many cases. Thermal diffusivity and thermal conductivity are unique for a given material because they are sensitive to the structure of the material. Therefore, it is important to measure them in each sample. However it is difficult to measure the thermal diffusivity and thermal conductivity of coatings because coatings are attached to substrates. In order to evaluate the thermal diffusivity of a coating attached to the substrate, we have examined the laser flash method with the multilayer model on the basis of the response function method. We carried out laser flash measurements in layered samples composed of a CoNiCrAlY bond coating and a 8YSZ top coating by thermal spraying on a Ni-based superalloy substrate. It was found that the procedure using laser flash method with the multilayer model is useful for the thermal diffusivity evaluation of a coating attached to a substrate. © 2011 The Japan Society of Applied Physics.


Xu C.,Ford Motor Company | Yang J.,Ford Motor Company | Pence B.L.,Ford Motor Company | Gath K.,Ford Motor Company | And 5 more authors.
ECS Transactions | Year: 2014

A two dimensional (2D) platinum network catalyst on graphitic carbon and amorphous NbOx hybrid support has been synthesized by the Arc Plasma Deposition (APD) method. The 2D platinum structure on the conductive, corrosion resistant amorphous metal oxide significantly increases the catalyst stability under RDE accelerated stress tests. RDE and 5cm2 MEA single cell test results show that the catalyst has higher specific and mass activities than those of conventionally prepared platinum on graphitic carbon (Pt/GC) catalyst. The microstructures of the catalyst were characterized by scanning tunneling microscopy (STM). © The Electrochemical Society.


PubMed | ULVAC RIKO Inc., Japan International Center for Materials Nanoarchitectonics and King Saud University
Type: Journal Article | Journal: Science and technology of advanced materials | Year: 2016

We have developed a new method of preparing Pt electrocatalysts through a dry process. By coaxial pulse arc plasma deposition (CAPD), highly ionized metal plasma can be generated from a target rod without any discharged gases, and Pt nanoparticles can be deposited on a carbon support. The small-sized Pt nanoparticles are distributed over the entire carbon surface. From transmission electron microscopy (TEM), the average size of the deposited Pt nanoparticles is estimated to be 2.5 nm, and their size distribution is narrow. Our electrocatalyst shows considerably improved catalytic activity and stability toward methanol oxidation reaction (MOR) compared with commercially available Pt catalysts such as Pt black and Pt/carbon (PtC). Inspired by its very high efficiency toward MOR, we also measured the catalytic performance for oxygen reduction reaction (ORR). Our PtC catalyst shows a better performance with half-wave potential of 0.87 V, which is higher than those of commercially available Pt catalysts. The higher performance is also supported by a right-shifted onset potential. Our preparation is simple and could be applied to other metallic nanocrystals as a novel platform in catalysis, fuel cells and biosensors.

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