Institute of Multidisciplinary Research for Advanced Materials, Tohoku University


LAST UPDATE 2021/05/04

  • 研究者氏名
    Researcher Name

    真木祥千子 Sachiko MAKI
    講師 Lecturer
  • 所属
    Professional Affiliation

    Institute of Multidisciplinary Research for Advanced Materials, Tohoku University

    プロセスシステム工学研究部門 ハイブリッドナノ粒子プロセス研究分野
    Division of Process and System Engineering, Hybrid Nano-particle
  • 研究キーワード
    Research Keywords

    single-/powder-crystal XRD measurement, XAFS measurement
    Maximum entropy method (MEM)/Rietveld analysis
    structure/property correlation in functional materials
Research Subject
Multimodal visualization of nano-scale structure/property ensemble by advanced synchrotron radiation measurement

研究の背景 Background


To improve practicality of functional materials, the “tuning of properties under trade-off state,” for example, high conductivity and low thermal conductivity in the thermoelectric materials, is essential in materials sciences. The development of the multimodal measurement system using synchrotron radiation (SR) requires not only the average atomic arrangement as crystal structure, but also other information related with non-stoichiometric effect as defects, heterogeneous tissue, structural fluctuation, etc.

研究の目標 Outcome

放射光による精密構造解析(単結晶・粉末試料)に加えて、吸収分光および光電子分光の測定から得られる電子状態の情報を活用し、電子構造と統合した構造情報の可視化を行う。それを、コヒーレント光を活用したタイコグラフィーの可視化により、メソスケール(10 nm程度)の構造乱れと電子状態の相関計測へマルチスケール化し、データ科学との融合により、巨視的サイズでの実用機能の設計指針をあたえることができる実用材料設計ツールを開発する。

(1) Visualization of information on the materials’ structure and electronic state by combining data from SR-xray diffraction, xray absorption spectroscopy, and photo emission spectroscopy. (2) Visualization of the correlation among properties, microscopic non-uniform structures, and their electronic states from the atomic scale to mesoscale crystalline field by utilizing xray ptychography.

研究図Research Figure

Fig.1. Profile fitting result by MEM/Rietveld refinement of Mg3Sb2-based thermoelectric material. (a) w/o Bi doping, (b) w/ Bi doping.

Fig.2. Temperature dependence of isotropic thermal factors.

Fig.3. The MEM charge densities of Mg3Sb2-based thermoelectric material. (a) w/o Bi doping, (b) w/ Bi doping, (c) 1D section profile aling c’-line.

文献 / Publications

Supercond. Sci. Technol. 31, 105002-1-105002-6 (2018), Phys. Rev. Lett. 31, 065701-1-065701-5 (2017), Phys. Rev. B 96, 125116-1-125116-5 (2017), Phys. Rev. B 96, 145101-1-045101-5 (2017), Phys. Rev. B 93, 121101-1-121101-5 (2016), Sci. Rep. 6, 39646-1-39646-6 (2016), J. Am. Chem. Soc. 135, 918-923 (2013)