金属リチウムイオン導体,LiNiNNの結晶化学と電子構造
Zlatka Stoeva1, Bernd Jäger, Ruben Gomez
1School of Chemistry, University of Nottingham, University Park, Nottingham NG7 2RD, U.K.
Journal of the American Chemical Society
|January 31, 2007
まとめ
層状のニトリドLiNiNは,急速なリチウムイオン拡散と金属特性を示し,リチウムイオン電池電極の有望な材料となっています. そのユニークな構造と結合は,これらの有利な特性に寄与しています.
科学分野:
- マテリアルサイエンス 材料科学
- 固体化学 固体化学
- 電気化学 電気化学について
背景:
- 層状の三元ナイトリドは,先進的なエネルギー貯蔵アプリケーションのために調査されています.
- ニトリウムリチウム (Li3N) は,関連する化合物の母体構造として機能します.
- 急速なイオン拡散と金属的振る舞いは,電池電極材料の望ましい特性である.
研究 の 目的:
- 層状の三重性ニトリドLiNiNの構造と性質を調査する.
- リチウムイオン電池の電極材料としてのLiNiNの可能性を評価する.
- 構造,結合,電気化学的性質の関係を理解する.
主な方法:
- 粉末中性子 difrakcionは,変化する温度で.
- 電子構造の初期計算について.
- SQUID磁気計は,磁気特性を測定する.
- 固体核磁共振 (NMR) スペクトロスコーピー. 固体核磁共振 (NMR) スペクトロスコーピー. 固体核磁共振 (NMR) スペクトロスコーピー. 固体核磁共振 (NMR) スペクトロスコーピー.
主要な成果:
- LiNiNは, Li3N構造の変形を形成し, Li+の空白と,層間の位置にある Ni (六角空間群 Pm2) を有しています.
- Ab initio計算では,LiNiNはc軸に沿ったNi-N pi-およびシグマ結合により1次元の金属であることを示しています.
- 温度変数のニュートロン difraktionと固体状態の7Li NMRは,高速のLi+イオン運動と金属の振る舞いを確認しています.
結論:
- LiNiNは,迅速なリチウムイオン輸送に有利なユニークな結晶構造を有しています.
- 特定のNi-N結合から生じる材料の1次元の金属性質が確認されています.
- LiNiNは,高性能リチウムイオン電池の電極材料として大きな可能性を秘めている.
関連する概念動画
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