Randy Jalem
(National Institute for Materials Science
)
;
Kazunori Takada
(National Institute for Materials Science
)
;
Hitoshi Onodera
;
Shuhei Yoshida
説明:
(abstract)Recently, a new oxide-type solid electrolyte (SE) for all-solid-state Li ion batteries, pyrochlore-type Li2−xLa(1+x)/3Nb2O6F (LLNOF), was reported to exhibit a Li+ superionic conductivity of 3.9 × 10−3 S cm−1 at room temperature. To gain understanding of this novel SE, in this work, thermodynamic analysis and ab initio molecular dynamics (AIMD) calculations based on the density functional theory (DFT) framework were performed to clarify the material's phase stability, electrochemical stability and Li+ ion transport properties. LLNOF is predicted to be a metastable phase, and thus, its electrochemical window is likely to be determined by its decomposition phases. The Li transport pathway is revealed to be defined by the large hexagonal tunnels formed by corner-sharing NbO6 units. These tunnels can either be La-free or La-blocked depending on the Li/La/vacancy configuration. The Li+ ion conduction mechanism proceeds in a concerted migration manner in the 16d sites via an intermediate site. Analysis of phonon density of states shows that F atoms have a lower phonon-energy band center position than O atoms; this is correlated with the characteristically low phonon-energy band center position of Li atoms and the observed Li+ superionic conductivity of LLNOF.
権利情報:
キーワード: all solid state batteries, solid electrolytes, first-principles calculation, molecular dynamics simulations
刊行年月日: 2024-10-28
出版者: Royal Society of Chemistry (RSC)
掲載誌:
研究助成金:
原稿種別: 著者最終稿 (Accepted manuscript)
MDR DOI: https://doi.org/10.48505/nims.5287
公開URL: https://doi.org/10.1039/d4ta04827j
関連資料:
その他の識別子:
連絡先:
更新時刻: 2025-10-28 08:30:19 +0900
MDRでの公開時刻: 2025-10-28 08:16:28 +0900
| ファイル名 | サイズ | |||
|---|---|---|---|---|
| ファイル名 |
LLNOF_main_rev_clean.pdf
application/pdf |
サイズ | 2.21MB | 詳細 |
| ファイル名 |
LLNOF_es1_rev_v3.pdf
(サムネイル)
application/pdf |
サイズ | 930KB | 詳細 |