Autor: |
Kevin Lemoine, Agnieszka Wizner, Sandy Auguste, Jean-Marc Grenèche, Hiroshi Kojitani, Masaki Akaogi, Yoshiyuki Inaguma |
Jazyk: |
angličtina |
Rok vydání: |
2021 |
Předmět: |
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Zdroj: |
Open Ceramics, Vol 6, Iss , Pp 100123- (2021) |
Druh dokumentu: |
article |
ISSN: |
2666-5395 |
DOI: |
10.1016/j.oceram.2021.100123 |
Popis: |
In the search of promising Na-ion cathode materials, high-pressure synthesis method was applied to obtain sodium iron fluoride NaFeF3 with the post-perovskite lamellar structure. A two-step synthesis was performed: first, the Pnma orthorhombic perovskite structure NaFeF3 form (or Pv-NaFeF3, GdFeO3 type) was synthesized at 1270 K and 7.7 GPa, then the Cmcm orthorhombic post-perovskite structure (or pPv-NaFeF3, CaIrO3 type) was obtained using a second step at 700 K and 15 GPa. The post-perovskite form was stabilized under ambient conditions with a low amount of remaining perovskite phase (5 mol%). The Mössbauer analysis of pPv-NaFeF3 was firstly investigated with a paramagnetic structure obtained at 300 and 77 K, opposed to Pv-NaFeF3 magnetism reflecting the different [FeF6] polyhedra arrangements. Finally, the sodium migration within the framework of both structures was evaluated with the use of Bond Valence Energy Landscape (BVEL) calculations, resulting with an enhanced Na+ mobility within the pPv-NaFeF3 structure. |
Databáze: |
Directory of Open Access Journals |
Externí odkaz: |
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