| Project/Area Number |
17F17349
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| Research Category |
Grant-in-Aid for JSPS Fellows
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| Allocation Type | Single-year Grants |
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| Section | 外国 |
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| Research Field |
Device related chemistry
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| Research Institution | The University of Tokyo |
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Principal Investigator |
山田 淳夫 東京大学, 大学院工学系研究科(工学部), 教授 (30359690)
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| Co-Investigator(Kenkyū-buntansha) |
LANDER LAURA 東京大学, 工学(系)研究科(研究院), 外国人特別研究員
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| Project Period (FY) |
2017-11-10 – 2020-03-31
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| Project Status |
Completed (Fiscal Year 2019)
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| Budget Amount *help |
¥2,300,000 (Direct Cost: ¥2,300,000)
Fiscal Year 2019: ¥200,000 (Direct Cost: ¥200,000)
Fiscal Year 2018: ¥1,100,000 (Direct Cost: ¥1,100,000)
Fiscal Year 2017: ¥1,000,000 (Direct Cost: ¥1,000,000)
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| Keywords | polyanions / layered oxides / Na-ion batteries / High-voltage cathode / Li-/Na-ion batteries |
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| Outline of Annual Research Achievements |
The goal of this JSPS fellowship is to identify new high-potential cathode materials for sodium-ion batteries. To this end, we studied the electrochemical properties of a Na-based heteropolyanionic SO4-PO3F solid-solution Na2Fe(SO4)2-x(PO3F)x.2H2O. The PO3F unit has not been studied as a polyanion for cathode materials so far and we were interested in its inductive effect and its impact on electrochemical performances. Galvanostatic cycling revealed elevated redox potentials for the PO3F polyanion. This would open the pathway to a new class of high-potential cathode materials. However, one drawback of this functional group is its low thermal stability. Therefore, we try to find additional synthesis routes to ensure an easy and reproducible preparation method of this compound.
A second project consists of the electrochemical and structural characterization of a Na-based layered oxide containing Ti4+ and Co2+, which displays a large hysteresis during Na (de)intercalation suggesting a spin transition of Co2+ upon oxidation. We are using a multi-angle approach with complementing characterization methods such as ex situ soft and hard X-ray absorption, magnetic measurements and galvanostatic intermittent titration technique (GITT) experiments to understand the underlying redox mechanism. Furthermore, we performed Density Functional Theory calculations to complement the experimental work with a theoretical viewpoint. The respective publication is under preparation.
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| Research Progress Status |
令和元年度が最終年度であるため、記入しない。
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| Strategy for Future Research Activity |
令和元年度が最終年度であるため、記入しない。
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