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Tetsuo Sakai - One of the best experts on this subject based on the ideXlab platform.

  • a novel thermic process for producing v Based Solid Solution type hydrogen storage alloy
    Materials Transactions, 2001
    Co-Authors: Akio Kawabata, Seiji Sakurai, Hiroyuki T Takeshita, Nobuhiro Kuriyama, M Tsukahara, K. Takahashi, Tetsuo Sakai, Hideo Yoshinaga, Yoshihisa Kamiya, Jun Shi
    Abstract:

    The performance of a high hydrogen capacity alloy, V-16%Ti-12%Ni-1.4%Nb-0.96%Co-2.8%Ta, is sensitively influenced by dissolved aluminum and oxygen, both of which can be removed from vanadium by a refining process, but the process currently used is too expensive. It is necessary to develop a process to remove these impurities at a reasonable cost. We propose a new method for production of the alloy. A V-15%Ni-1.8%Nb precursor with a low enough level of aluminum was produced by alumino-thermic reduction from a mixture of V 2 O 5 , Nb 2 O 5 and nickel. Subsequently, a V-16%Ti-12%Ni-1.4%Nb-0.96%Co-2.8%Ta alloy was obtained by alloying the precursor and the other constituents of titanium, cobalt and tantalum, and by adding mischmetal as a reducing agent to remove oxygen to a low enough level. It was demonstrated that, by the method described here, the vanadium-Based alloy could be produced at a reasonable cost.

  • Hydrogen Storage and Electrode Properties of V‐Based Solid Solution Type Alloys Prepared by a Thermic Process
    Journal of The Electrochemical Society, 2000
    Co-Authors: M Tsukahara, Seiji Sakurai, Hiroyuki T Takeshita, T. Kamiya, Nobuhiro Kuriyama, Jun Shi, K. Takahashi, Atsufumi Kawabata, Tetsuo Sakai
    Abstract:

    A vanadium-Based Solid-Solution-type alloy V 4 TiNi 0.65 Co 0.05 Nb 0.047 Ta 0.047 with a large discharge capacity was obtained using a low-cost precursor of V 4 Ni 0.65 Nb 0.047 produced by aluminothermic reduction from V 2 O 5 , Nb 2 O 5 , and Ni, The alloy was deoxidized to a low level by adding mischmetal as a reducing agent when the precursor was alloyed with Ti, Co, and Ta. The alloy showed a hydrogen absorption behavior similar to an alloy prepared from high-purity constituent metals. Moreover, the Mm-Ni-O phase was precipitated as spherical particles along the TiNi network phase in the alloy, remarkably improving the electrode rate capability because of enhanced catalytic ability of the network phase.

  • vanadium Based Solid Solution alloys with three dimensional network structure for high capacity metal hydride electrodes
    Journal of Alloys and Compounds, 1997
    Co-Authors: M Tsukahara, K. Takahashi, A. Isomura, Takahiro Mishima, Tetsuo Sakai
    Abstract:

    Abstract V-Based alloys with a 3-D network structure of a TiNi phase provided high-capacity metal hydride electrodes for Ni–MH cells. The network of TiNi phase worked as a micro-current collector and electro-catalyst. It was shown that the micro-structure and chemical composition of the network phase remarkably influenced the electrochemical properties of the V-Based alloys. The kinetics of the electrochemical reaction of V3TiNix depended mainly on the volume fraction of the TiNi phase. The cyclic durability was improved by decreasing vanadium content in the TiNi phase by heat-treatment. A network of C14-Laves type phase containing Hf could improve the high rate capability, while a network phase of C14-Laves type phase containing Zr could not. By adding Co, Nb and Ta to a V–Ti–Ni alloy, the durability during charge–discharge cycles was remarkably improved.

  • heat treatment effects of v Based Solid Solution alloy with tini Based network structure on hydrogen storage and electrode properties
    Journal of Alloys and Compounds, 1996
    Co-Authors: M Tsukahara, K. Takahashi, T. Mishima, A. Isomura, Tetsuo Sakai
    Abstract:

    Abstract Heat-treatment at 973–1473 K was conducted on a V 3 TiNi 0.56 alloy which consisted of a V-Based Solid Solution main phase for hydrogen storage and a TiNi-Based secondary phase for electrochemical reaction. Heat-treatment at 1073 K was found to improve the durability during electrical charge-discharge cycles in NiMH cells because the corrosive vanadium content in the secondary phase was decreased by the heat-treatment. High-rate capability, however, was decreased by heat-treatment above 1273 K because of the increased grain size of the main phase and degradation of the TiNi-Based network structure of the secondary phase.

  • V-Based Solid Solution alloys with Laves phase network: Hydrogen absorption properties and microstructure
    Journal of Alloys and Compounds, 1996
    Co-Authors: M Tsukahara, K. Takahashi, T. Mishima, A. Isomura, Tetsuo Sakai
    Abstract:

    Abstract Hydrogen absorption-desorption properties, microstructures and electrode properties of V-Based Solid Solution alloys (V3TiNi0.56Hfx, x = 0.046 and 0.24) were reported. In these alloys a Laves phase was precipitated, forming a three-dimensional network along grain boundaries of a V-Based Solid Solution main phase. Cracking was observed to occur in and around the Laves phase after several charge-discharge cycles. The increase in fresh surface area was very useful in enhancing the high-rate capability of the electrode.

M Tsukahara - One of the best experts on this subject based on the ideXlab platform.

  • a novel thermic process for producing v Based Solid Solution type hydrogen storage alloy
    Materials Transactions, 2001
    Co-Authors: Akio Kawabata, Seiji Sakurai, Hiroyuki T Takeshita, Nobuhiro Kuriyama, M Tsukahara, K. Takahashi, Tetsuo Sakai, Hideo Yoshinaga, Yoshihisa Kamiya, Jun Shi
    Abstract:

    The performance of a high hydrogen capacity alloy, V-16%Ti-12%Ni-1.4%Nb-0.96%Co-2.8%Ta, is sensitively influenced by dissolved aluminum and oxygen, both of which can be removed from vanadium by a refining process, but the process currently used is too expensive. It is necessary to develop a process to remove these impurities at a reasonable cost. We propose a new method for production of the alloy. A V-15%Ni-1.8%Nb precursor with a low enough level of aluminum was produced by alumino-thermic reduction from a mixture of V 2 O 5 , Nb 2 O 5 and nickel. Subsequently, a V-16%Ti-12%Ni-1.4%Nb-0.96%Co-2.8%Ta alloy was obtained by alloying the precursor and the other constituents of titanium, cobalt and tantalum, and by adding mischmetal as a reducing agent to remove oxygen to a low enough level. It was demonstrated that, by the method described here, the vanadium-Based alloy could be produced at a reasonable cost.

  • hydrogen storage and electrode properties of v Based Solid Solution type alloys prepared by a thermic process
    Journal of The Electrochemical Society, 2000
    Co-Authors: M Tsukahara, Seiji Sakurai, Hiroyuki T Takeshita, Akio Kawabata, T. Kamiya, Nobuhiro Kuriyama, Jun Shi, K. Takahashi, T Sakai
    Abstract:

    A vanadium-Based Solid-Solution-type alloy V 4 TiNi 0.65 Co 0.05 Nb 0.047 Ta 0.047 with a large discharge capacity was obtained using a low-cost precursor of V 4 Ni 0.65 Nb 0.047 produced by aluminothermic reduction from V 2 O 5 , Nb 2 O 5 , and Ni, The alloy was deoxidized to a low level by adding mischmetal as a reducing agent when the precursor was alloyed with Ti, Co, and Ta. The alloy showed a hydrogen absorption behavior similar to an alloy prepared from high-purity constituent metals. Moreover, the Mm-Ni-O phase was precipitated as spherical particles along the TiNi network phase in the alloy, remarkably improving the electrode rate capability because of enhanced catalytic ability of the network phase.

  • Hydrogen Storage and Electrode Properties of V‐Based Solid Solution Type Alloys Prepared by a Thermic Process
    Journal of The Electrochemical Society, 2000
    Co-Authors: M Tsukahara, Seiji Sakurai, Hiroyuki T Takeshita, T. Kamiya, Nobuhiro Kuriyama, Jun Shi, K. Takahashi, Atsufumi Kawabata, Tetsuo Sakai
    Abstract:

    A vanadium-Based Solid-Solution-type alloy V 4 TiNi 0.65 Co 0.05 Nb 0.047 Ta 0.047 with a large discharge capacity was obtained using a low-cost precursor of V 4 Ni 0.65 Nb 0.047 produced by aluminothermic reduction from V 2 O 5 , Nb 2 O 5 , and Ni, The alloy was deoxidized to a low level by adding mischmetal as a reducing agent when the precursor was alloyed with Ti, Co, and Ta. The alloy showed a hydrogen absorption behavior similar to an alloy prepared from high-purity constituent metals. Moreover, the Mm-Ni-O phase was precipitated as spherical particles along the TiNi network phase in the alloy, remarkably improving the electrode rate capability because of enhanced catalytic ability of the network phase.

  • vanadium Based Solid Solution alloys with three dimensional network structure for high capacity metal hydride electrodes
    Journal of Alloys and Compounds, 1997
    Co-Authors: M Tsukahara, K. Takahashi, A. Isomura, Takahiro Mishima, Tetsuo Sakai
    Abstract:

    Abstract V-Based alloys with a 3-D network structure of a TiNi phase provided high-capacity metal hydride electrodes for Ni–MH cells. The network of TiNi phase worked as a micro-current collector and electro-catalyst. It was shown that the micro-structure and chemical composition of the network phase remarkably influenced the electrochemical properties of the V-Based alloys. The kinetics of the electrochemical reaction of V3TiNix depended mainly on the volume fraction of the TiNi phase. The cyclic durability was improved by decreasing vanadium content in the TiNi phase by heat-treatment. A network of C14-Laves type phase containing Hf could improve the high rate capability, while a network phase of C14-Laves type phase containing Zr could not. By adding Co, Nb and Ta to a V–Ti–Ni alloy, the durability during charge–discharge cycles was remarkably improved.

  • heat treatment effects of v Based Solid Solution alloy with tini Based network structure on hydrogen storage and electrode properties
    Journal of Alloys and Compounds, 1996
    Co-Authors: M Tsukahara, K. Takahashi, T. Mishima, A. Isomura, Tetsuo Sakai
    Abstract:

    Abstract Heat-treatment at 973–1473 K was conducted on a V 3 TiNi 0.56 alloy which consisted of a V-Based Solid Solution main phase for hydrogen storage and a TiNi-Based secondary phase for electrochemical reaction. Heat-treatment at 1073 K was found to improve the durability during electrical charge-discharge cycles in NiMH cells because the corrosive vanadium content in the secondary phase was decreased by the heat-treatment. High-rate capability, however, was decreased by heat-treatment above 1273 K because of the increased grain size of the main phase and degradation of the TiNi-Based network structure of the secondary phase.

K. Takahashi - One of the best experts on this subject based on the ideXlab platform.

  • a novel thermic process for producing v Based Solid Solution type hydrogen storage alloy
    Materials Transactions, 2001
    Co-Authors: Akio Kawabata, Seiji Sakurai, Hiroyuki T Takeshita, Nobuhiro Kuriyama, M Tsukahara, K. Takahashi, Tetsuo Sakai, Hideo Yoshinaga, Yoshihisa Kamiya, Jun Shi
    Abstract:

    The performance of a high hydrogen capacity alloy, V-16%Ti-12%Ni-1.4%Nb-0.96%Co-2.8%Ta, is sensitively influenced by dissolved aluminum and oxygen, both of which can be removed from vanadium by a refining process, but the process currently used is too expensive. It is necessary to develop a process to remove these impurities at a reasonable cost. We propose a new method for production of the alloy. A V-15%Ni-1.8%Nb precursor with a low enough level of aluminum was produced by alumino-thermic reduction from a mixture of V 2 O 5 , Nb 2 O 5 and nickel. Subsequently, a V-16%Ti-12%Ni-1.4%Nb-0.96%Co-2.8%Ta alloy was obtained by alloying the precursor and the other constituents of titanium, cobalt and tantalum, and by adding mischmetal as a reducing agent to remove oxygen to a low enough level. It was demonstrated that, by the method described here, the vanadium-Based alloy could be produced at a reasonable cost.

  • hydrogen storage and electrode properties of v Based Solid Solution type alloys prepared by a thermic process
    Journal of The Electrochemical Society, 2000
    Co-Authors: M Tsukahara, Seiji Sakurai, Hiroyuki T Takeshita, Akio Kawabata, T. Kamiya, Nobuhiro Kuriyama, Jun Shi, K. Takahashi, T Sakai
    Abstract:

    A vanadium-Based Solid-Solution-type alloy V 4 TiNi 0.65 Co 0.05 Nb 0.047 Ta 0.047 with a large discharge capacity was obtained using a low-cost precursor of V 4 Ni 0.65 Nb 0.047 produced by aluminothermic reduction from V 2 O 5 , Nb 2 O 5 , and Ni, The alloy was deoxidized to a low level by adding mischmetal as a reducing agent when the precursor was alloyed with Ti, Co, and Ta. The alloy showed a hydrogen absorption behavior similar to an alloy prepared from high-purity constituent metals. Moreover, the Mm-Ni-O phase was precipitated as spherical particles along the TiNi network phase in the alloy, remarkably improving the electrode rate capability because of enhanced catalytic ability of the network phase.

  • Hydrogen Storage and Electrode Properties of V‐Based Solid Solution Type Alloys Prepared by a Thermic Process
    Journal of The Electrochemical Society, 2000
    Co-Authors: M Tsukahara, Seiji Sakurai, Hiroyuki T Takeshita, T. Kamiya, Nobuhiro Kuriyama, Jun Shi, K. Takahashi, Atsufumi Kawabata, Tetsuo Sakai
    Abstract:

    A vanadium-Based Solid-Solution-type alloy V 4 TiNi 0.65 Co 0.05 Nb 0.047 Ta 0.047 with a large discharge capacity was obtained using a low-cost precursor of V 4 Ni 0.65 Nb 0.047 produced by aluminothermic reduction from V 2 O 5 , Nb 2 O 5 , and Ni, The alloy was deoxidized to a low level by adding mischmetal as a reducing agent when the precursor was alloyed with Ti, Co, and Ta. The alloy showed a hydrogen absorption behavior similar to an alloy prepared from high-purity constituent metals. Moreover, the Mm-Ni-O phase was precipitated as spherical particles along the TiNi network phase in the alloy, remarkably improving the electrode rate capability because of enhanced catalytic ability of the network phase.

  • vanadium Based Solid Solution alloys with three dimensional network structure for high capacity metal hydride electrodes
    Journal of Alloys and Compounds, 1997
    Co-Authors: M Tsukahara, K. Takahashi, A. Isomura, Takahiro Mishima, Tetsuo Sakai
    Abstract:

    Abstract V-Based alloys with a 3-D network structure of a TiNi phase provided high-capacity metal hydride electrodes for Ni–MH cells. The network of TiNi phase worked as a micro-current collector and electro-catalyst. It was shown that the micro-structure and chemical composition of the network phase remarkably influenced the electrochemical properties of the V-Based alloys. The kinetics of the electrochemical reaction of V3TiNix depended mainly on the volume fraction of the TiNi phase. The cyclic durability was improved by decreasing vanadium content in the TiNi phase by heat-treatment. A network of C14-Laves type phase containing Hf could improve the high rate capability, while a network phase of C14-Laves type phase containing Zr could not. By adding Co, Nb and Ta to a V–Ti–Ni alloy, the durability during charge–discharge cycles was remarkably improved.

  • heat treatment effects of v Based Solid Solution alloy with tini Based network structure on hydrogen storage and electrode properties
    Journal of Alloys and Compounds, 1996
    Co-Authors: M Tsukahara, K. Takahashi, T. Mishima, A. Isomura, Tetsuo Sakai
    Abstract:

    Abstract Heat-treatment at 973–1473 K was conducted on a V 3 TiNi 0.56 alloy which consisted of a V-Based Solid Solution main phase for hydrogen storage and a TiNi-Based secondary phase for electrochemical reaction. Heat-treatment at 1073 K was found to improve the durability during electrical charge-discharge cycles in NiMH cells because the corrosive vanadium content in the secondary phase was decreased by the heat-treatment. High-rate capability, however, was decreased by heat-treatment above 1273 K because of the increased grain size of the main phase and degradation of the TiNi-Based network structure of the secondary phase.

Jun Shi - One of the best experts on this subject based on the ideXlab platform.

  • a novel thermic process for producing v Based Solid Solution type hydrogen storage alloy
    Materials Transactions, 2001
    Co-Authors: Akio Kawabata, Seiji Sakurai, Hiroyuki T Takeshita, Nobuhiro Kuriyama, M Tsukahara, K. Takahashi, Tetsuo Sakai, Hideo Yoshinaga, Yoshihisa Kamiya, Jun Shi
    Abstract:

    The performance of a high hydrogen capacity alloy, V-16%Ti-12%Ni-1.4%Nb-0.96%Co-2.8%Ta, is sensitively influenced by dissolved aluminum and oxygen, both of which can be removed from vanadium by a refining process, but the process currently used is too expensive. It is necessary to develop a process to remove these impurities at a reasonable cost. We propose a new method for production of the alloy. A V-15%Ni-1.8%Nb precursor with a low enough level of aluminum was produced by alumino-thermic reduction from a mixture of V 2 O 5 , Nb 2 O 5 and nickel. Subsequently, a V-16%Ti-12%Ni-1.4%Nb-0.96%Co-2.8%Ta alloy was obtained by alloying the precursor and the other constituents of titanium, cobalt and tantalum, and by adding mischmetal as a reducing agent to remove oxygen to a low enough level. It was demonstrated that, by the method described here, the vanadium-Based alloy could be produced at a reasonable cost.

  • hydrogen storage and electrode properties of v Based Solid Solution type alloys prepared by a thermic process
    Journal of The Electrochemical Society, 2000
    Co-Authors: M Tsukahara, Seiji Sakurai, Hiroyuki T Takeshita, Akio Kawabata, T. Kamiya, Nobuhiro Kuriyama, Jun Shi, K. Takahashi, T Sakai
    Abstract:

    A vanadium-Based Solid-Solution-type alloy V 4 TiNi 0.65 Co 0.05 Nb 0.047 Ta 0.047 with a large discharge capacity was obtained using a low-cost precursor of V 4 Ni 0.65 Nb 0.047 produced by aluminothermic reduction from V 2 O 5 , Nb 2 O 5 , and Ni, The alloy was deoxidized to a low level by adding mischmetal as a reducing agent when the precursor was alloyed with Ti, Co, and Ta. The alloy showed a hydrogen absorption behavior similar to an alloy prepared from high-purity constituent metals. Moreover, the Mm-Ni-O phase was precipitated as spherical particles along the TiNi network phase in the alloy, remarkably improving the electrode rate capability because of enhanced catalytic ability of the network phase.

  • Hydrogen Storage and Electrode Properties of V‐Based Solid Solution Type Alloys Prepared by a Thermic Process
    Journal of The Electrochemical Society, 2000
    Co-Authors: M Tsukahara, Seiji Sakurai, Hiroyuki T Takeshita, T. Kamiya, Nobuhiro Kuriyama, Jun Shi, K. Takahashi, Atsufumi Kawabata, Tetsuo Sakai
    Abstract:

    A vanadium-Based Solid-Solution-type alloy V 4 TiNi 0.65 Co 0.05 Nb 0.047 Ta 0.047 with a large discharge capacity was obtained using a low-cost precursor of V 4 Ni 0.65 Nb 0.047 produced by aluminothermic reduction from V 2 O 5 , Nb 2 O 5 , and Ni, The alloy was deoxidized to a low level by adding mischmetal as a reducing agent when the precursor was alloyed with Ti, Co, and Ta. The alloy showed a hydrogen absorption behavior similar to an alloy prepared from high-purity constituent metals. Moreover, the Mm-Ni-O phase was precipitated as spherical particles along the TiNi network phase in the alloy, remarkably improving the electrode rate capability because of enhanced catalytic ability of the network phase.

Yuan Deng - One of the best experts on this subject based on the ideXlab platform.

  • Correction: High thermoelectric performance of a defect in α-In2Se3-Based Solid Solution upon substitution of Zn for In
    Journal of Materials Chemistry C, 2015
    Co-Authors: Jiaolin Cui, Li Wang, Pengzhan Ying, Yuan Deng
    Abstract:

    Correction for ‘High thermoelectric performance of a defect in α-In2Se3-Based Solid Solution upon substitution of Zn for In’ by Jiaolin Cui et al., J. Mater. Chem. C, 2015, 3, 9069–9075.

  • High thermoelectric performance of a defect in α-In2Se3-Based Solid Solution upon substitution of Zn for In
    Journal of Materials Chemistry C, 2015
    Co-Authors: Jiaolin Cui, Li Wang, Pengzhan Ying, Yuan Deng
    Abstract:

    In this project, we have successfully manipulated the lattice defects in α-In2Se3-Based Solid Solutions (In2−xZnxSe3) by appropriate substitution of Zn for In, via a non-equilibrium fabrication technology (NEFT) of materials. The manipulation of the defect centers involves reduction of the number of interstitial In atoms (Ini) and Se vacancies (VSe), and creation of a new antisite defect ZnIn as a donor. Through this technique, the lattice structure tends to be ordered, and also more stabilized than that of pure α-In2Se3. In the meantime, the carrier concentration (n) and mobility (μ) have increased by 1–2 orders of magnitude. As a consequence, the Solid Solution at x = 0.01 gives the highest TE figure of merit (ZT) of 1.23(±0.22) in the pressing direction at 916 K, which is about 4.7 times that of pure α-In2Se3 (ZT = 0.26). This achieved TE performance is mainly due to the remarkable improvement in the electrical conductivity from 0.53 × 103 (Ω−1 m−1) at x = 0 to 4.88 × 103 (Ω−1 m−1) at x = 0.01 at 916 K, in spite of the enhancement in the lattice thermal conductivity (κL) from 0.26 (W m−1 K−1) to 0.32 (W m−1 K−1).