Development of mapping method of valency and spin state of 3d transition metal elements

2020 Fiscal Year Final Research Report

• Project/Area Number: 19K21838
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 13:Condensed matter physics and related fields
• Research Institution: Tohoku University
• Principal Investigator: Terauchi Masami 東北大学, 多元物質科学研究所, 教授 (30192652)
• Project Period (FY): 2019-06-28 – 2021-03-31
• Keywords: 3d遷移金属元素 / 軟X線発光分光 / 価電子状態 / スピン状態

Outline of Final Research Achievements

Performance of functional materials, such as large-capacity rechargeable battery materials, depends on the valency and its spin state of 3d transition metal elements. To reveal the distribution of those states, a high energy resolution soft X-ray emission spectroscopy (SXES) method is aimed to combine with electron microscopy.
(1) A larger energy dispersion SXES spectrometer was designed, manufactured and attached to an electron probe microanalyzer. The resolution was evaluated to be 2.2 times larger than that of a conventional SXES instrument for electron microscope.
(2) Systematic measurements of L-emission of Mn, Fe, Cu, and those oxides were done. a) Clear detection of chemical shifts in La-emission peak due to different valency was achieved. 2) Additional shoulder structure due to a spin-orbit interaction between a magnetic moment of 3d-shell and the spin of 3s core-hole was successfully observed as an additional shoulder structure of Ll-emission peak.

Free Research Field

物性物理

Academic Significance and Societal Importance of the Research Achievements

社会を豊かで持続可能なものにするためには、高機能マテリアル開発のスピードアップが必須である。そのためには、合成物質の高精度な評価のハイスループット化とその合成プロセスへのフィードバックが必要不可欠である。開発を目指している新たな顕微SXES手法による価数状態・スピン状態分析技術は、世界でいまだ開拓されていない分析技術分野である。また、これまでにないナノとマクロの中間的空間スケールでの分析技術という特徴を有する。これを実現して社会へ普及させることで、機能性材料開発のスピードアップに貢献できる。