Investigation of hydrogenation properties focusing the electronic states in transition metal hydrides(Fostering Joint International Research)

• Project/Area Number: 15KK0168
• Research Category: Fund for the Promotion of Joint International Research (Fostering Joint International Research)
• Allocation Type: Multi-year Fund
• Research Field: Structural/Functional materials
• Research Institution: Hiroshima University
• Principal Investigator: Ishimatsu Naoki 広島大学, 理学研究科, 助教 (70343291)
• Research Collaborator: Pascarelli S. The European Synchrotron Radiation Facility(ESRF), Matter of Extremes group, Leader of Matter of Extremes group
• Project Period (FY): 2016 – 2017
• Project Status: Completed (Fiscal Year 2017)
• Budget Amount: ¥7,540,000 (Direct Cost: ¥5,800,000、Indirect Cost: ¥1,740,000)
• Keywords: X線吸収分光 / 高圧力 / 金属水素化物 / X線吸収分光法 / コバルト

Outline of Final Research Achievements

I stayed at the ESRF and collaborated with S. Pascarelli and her research group to study the local structure and magnetic states of metal hydride system by using X-ray absorption technique. Extended X-ray absorption fine structure (EXAFS) spectra of CoHx were measured at the Co K-edge under high pressure and at room temperature. The structural change of the Co sublattice from hcp to fcc via hydrogenation was analyzed quantitatively from the viewpoint of the local structure around Co. A model of randomly occupied hydrogen atoms accurately reproduced the experimental EXAFS profiles, indicating that the hydrogen atoms are located randomly in the Co sublattice. I also performed XAS studies of Laves phase compounds and laser-heating experiments to understand the advantages and disadvantages of the energy-dispersive x-ray optics. Fruitful discussion about material science under high pressure using XAS was achieved with the group of S. Pascarelli during the stay at ESRF.

Research Products

• [Int'l Joint Research] European Synchrotron Radiation Facility（ESRF)(フランス) (2016)
• [Journal Article] Relationship between element-selective electronic states and hydrogen absorption properties of Pd-M (M =Ru, Rh, Ag, and Au) alloys (2017)
  • Author(s): Kanako Fujii, Naoki Ishimatsu, Hiroshi Maruyama, Tatsuya Shishidou, Shinjiro Hayakawa, and Naomi Kawamura
  • Journal Title: PHYSICAL REVIEW B Volume: 95 Issue: 2
  • DOI: 10.1103/physrevb.95.024116
  • Peer Reviewed
• [Journal Article] Applications of nano-polycrystalline diamond anvils to X-ray absorption spectroscopy under high pressure (2016)
  • Author(s): N. Ishimatsu, N. Kawamura, M. Mizumaki, H. Maruyama, H. Sumiya, and T. Irifune
  • Journal Title: High Pressure Research Volume: 36 Issue: 3 Pages: 381-390
  • DOI: 10.1080/08957959.2016.1205048
  • Peer Reviewed
• [Journal Article] High-Pressure-Hydrogen-Induced Spin Reconfiguration in GdFe2 Observed by 57Fe-Polarized Synchrotron Radiation Mössbauer Spectroscopy with Nuclear Bragg Monochromator (2016)
  • Author(s): Takaya Mitsui, Yasuhiko Imai, Naohisa Hirao, Takahiro Matsuoka, Yumiko Nakamura, Kouji Sakaki, Hirotoshi Enoki, Naoki Ishimatsu, Ryo Masuda, Makoto Seto
  • Journal Title: Journal of the Physical Society of Japan Volume: 85 Issue: 12 Pages: 1237071-5
  • DOI: 10.7566/jpsj.85.123707
  • NAID: 210000134177
  • Peer Reviewed / Acknowledgement Compliant
• [Presentation] EXAFS local structural analysis of amorphous phase transition under high pressure in type I clathrate compound Eu8Ga16Ge30 (2018)
  • Author(s): K. Yokoyama，N. Ishimatsu，H. Maruyama，T. Onimaru，T. Takabatake，K. Suekuni， N. Kawamura，M. Mizumaki，S. Tsutsui，T. Ina，T. Watanuki，T. Irifune， V. Cuartero，O. Mathon，S. Pascarelli
  • Organizer: 1st international workshop of Emergent Condensed-Matter Physics 2018
  • Int'l Joint Research
• [Presentation] X 線吸収分光法でみる Pd 基合金の元素選択的な水素吸蔵特性 (2018)
  • Author(s): 石松直樹
  • Organizer: 第78回分析化学討論会
  • Invited
• [Presentation] Hydrogenation process and local structure of CoHx under high pressure studied by EXAFS (2017)
  • Author(s): Naoki Ishimtasu, Taishi Toryu, Kei Yokoyama, Hiroshi Maruyama, Satoshi Nakano, Vera Cuartero Yague, and Sakura Pascarelli
  • Organizer: 27th ESRF user meeting 2017
  • Place of Presentation: ESRF, Grenoble, France
  • Year and Date: 2017-02-06
  • Int'l Joint Research
• [Presentation] X 線吸収分光法によるCoの圧力誘起水素化過程の局所構造解析 (2017)
  • Author(s): 鳥生泰志, 石松直樹, 横山渓, 圓山裕, 中野智志, V. Cuartero, R. Torchio, O. Mathon, S. Pascarelli
  • Organizer: 第58回高圧討論会
• [Presentation] ESRF XAFS/XMCDビームラインBM23とID24での圧力下実験の報告 (2017)
  • Author(s): 石松直樹
  • Organizer: 高圧物質科学研究会
  • Invited
• [Presentation] Hydrogenation process of Co metal studied by extended X-ray absorption fine structure (EXAFS) under pressure (2017)
  • Author(s): T. Toryu, N. Ishimatsu, K. Yokoyama, H. Maruyama, S. Nakano, V. Cuartero, R. Torchio, and S. Pascarelli
  • Organizer: The 26th International Conference on High Pressure Science & Technology (AIRAPT 26)
  • Int'l Joint Research
• [Presentation] エネルギー分散型EXAFS 測定によるCo の圧力誘起水素化過程の局所構造解析 (2017)
  • Author(s): 鳥生泰志, 石松直樹, 横山溪, 圓山裕, 中野智志, V. Cuartero, R. Torchio, O. Mathon, S. Pascarelli
  • Organizer: 第20回XAFS討論会
• [Presentation] クラスレート化合物X8Ga16Ge30（X=Eu,Sr,Ba）のGe K端及びEu K端EXAFS解析 (2017)
  • Author(s): 横山渓，石松直樹，鳥生泰志，圓山裕，加藤盛也，岩崎駿，鬼丸孝博，高畠敏郎，末國晃一郎，河村直己，水牧仁一朗，筒井智嗣，伊奈稔哲，綿貫徹, 入舩徹男，V. Cuartero，O. Mathon，S. Pascarelli
  • Organizer: 第20回XAFS討論会
• [Presentation] Magnetism of metal hydrides under high pressure: X-ray spectroscopic studies (2016)
  • Author(s): Naoki Ishimatsu
  • Organizer: ESRF Magnetism Meeting
  • Place of Presentation: the Science Building ESRF, Grenoble, France
  • Year and Date: 2016-11-24
  • Int'l Joint Research / Invited
• [Book] XAFSの基礎と応用 (2017)
  • Author(s): 日本XAFS研究会 (共著）
  • Total Pages: 352
  • Publisher: 講談社
  • ISBN: 9784061532953