3D imaging of dopants by X-ray fluorescence and neutron holography

2018 Fiscal Year Final Research Report

• Project Area: 3D Active-Site Science
• Project/Area Number: 26105006
• Research Category: Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area)
• Allocation Type: Single-year Grants
• Review Section: Science and Engineering
• Research Institution: Nagoya Institute of Technology
• Principal Investigator: HAYASHI Koichi 名古屋工業大学, 工学(系)研究科(研究院), 教授 (20283632)
• Co-Investigator(Kenkyū-buntansha): 細川 伸也 熊本大学, 大学院先端科学研究部(理), 教授 (30183601) ; 大山 研司 茨城大学, 理工学研究科(工学野), 教授 (60241569)
• Research Collaborator: Kimura Koji
• Project Period (FY): 2014-07-10 – 2019-03-31
• Keywords: 蛍光X線ホログラフィー / 中性子ホログラフィー / 局所構造 / 三次元原子像 / たんぱく質 / 価数選択解析

Outline of Final Research Achievements

We proposed four goals, such as (1): development of neutron holography, (2): light-element imaging, (3): active-site imaging in protein, and (4): sit-selective imaging. Regrading (1), multiple-wavelength neutron holography was successfully demonstrated with the sample of Eu-doped CaF2 single crystal. Moreover, it was applied to the local structure characterization of B-doped materials. Regarding (2), a new apparatus of X-ray fluorescence holography equipped with a small cylindrical graphite analyzer was constructed and it was applied to the imaging of local structures around Ca and K in superconductors. Regarding (3), by introducing liq. N2 flowing system and kai stage, we could establish the method of hologram measurement of proteins under low radiation damage. Then, holograms of hemoglobin and myoglobin proteins were measured to image heme structures around Fe. Regarding (4), using resonant excitation at absorption edges, valence-selective hologram measurements.

Free Research Field

理工学

Academic Significance and Societal Importance of the Research Achievements

蓄電池や燃料電池等のエネルギー関連の材料は、リチウムや水素などの軽元素を利用したものが多い。軽元素に対応した蛍光X線ホログラフィーや中性子線ホログラフィーは、従来、困難としてきた、これら軽元素の局所構造を３Dで示すことができるために、材料科学におけるインパクトは非常に大きい。また、これまでに全く対象とされてこなかったバイオ物質に対して蛍光X線ホログラフィーが適用できることを示せたため、生物物理学分野への原子イメージングの展開が今後期待される。