メタステーブルNb2O5ブロンズフェーズにおけるナノ構造化なしの高速インターケレーション
Kent J Griffith1, Alexander C Forse1, John M Griffin1
1Department of Chemistry, University of Cambridge , Cambridge CB2 1EW, U.K.
Journal of the American Chemical Society
|June 7, 2016
まとめ
ニオビウムペンタオキシド (Nb2O5) の高容量と高速充電率は,その塊結晶構造の固有特性であり,エネルギー貯蔵アプリケーションではナノ構造化を必要としません.
科学分野:
- 材料科学
- 電気化学
- 固体化学
背景:
- ナノ構造は エネルギー貯蔵材料の性能を高めるための一般的な戦略です
- ニオビウムペンタオキシド (Nb2O5) のポリモルフはリチウムインターケレーションのために探求されている.
研究 の 目的:
- Nb2O5のTとTT相の固有の電気化学的性質を調査する.
- Nb2O5で高い容量と速度の性能を達成するためにナノ構造化が不可欠であるかどうかを判断する.
主な方法:
- マイクロメートルサイズのNb2O5粒子の電気化学分析
- 高解像度 (6/7) Li固体核磁気共振 (NMR) スペクトロスコーピー
- リチウムのダイナミクスを研究する.
主要な成果:
- T相のNb2O5は,ナノ構造化なしに60Cまでのオム値低下によってのみ制限される高容量を示す.
- H相Nb2O5は,中程度の速度で高いインターケレーション能力を示しています.
- NMRは,低活性化エネルギーを持つT-Nb2O5の急速なリチウムダイナミクスを明らかにします.
結論:
- T-とTT-Nb2O5の容量と速度性能は,その塊結晶構造の固有の特性です.
- 高速性能は,ナノ構造化なしで複雑な絶縁酸化物で達成できます.
- Nb2O5は,その特殊な性質と合成により,エネルギー貯蔵の応用として考慮に値する.
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