快速リチオン伝導のためのカチオン共性有機枠ナノシート
Hongwei Chen1, Hangyu Tu1, Chenji Hu2
1College of Materials Science and Engineering, Huaqiao University , Xiamen 361021, People's Republic of China.
Journal of the American Chemical Society
|January 6, 2018
まとめ
組み込まれたカチオンの骨格を持つ共性有機フレームワーク (COF) は,イオンペアを分割することによってリチウムイオン伝導性を高めます. この突破は電池の 固体電解質の改良に 有望な経路を示しています
科学分野:
- 材料科学
- 電気化学
- 固体イオン
背景:
- コヴァレンント有機フレームワーク (COF) は,孔状構造のため,リチウムイオン電池の固体電解質として調査されています.
- COFに浸透したリチウム塩はしばしばイオンペアを形成し,効率的なリチウムイオン (Li+) 伝導を妨げます.
- これらのイオンペアを分離する戦略を開発することは,イオン伝導性を改善するために不可欠です.
研究 の 目的:
- 固体リチウムイオン導体アプリケーションのためのCOFのイオン伝導性を高める.
- COFの毛穴内のLi+塩イオンペアリングによって引き起こされる遅いイオン拡散の制限に対処するために.
- Li+輸送の改善のためのCOFにカチオンの骨格を組み込む効果を調査する.
主な方法:
- 統合されたカチオン骨格を備えたCOFの設計と合成
- 変更されたCOF構造にLi+塩を組み込む.
- Li+伝導性を測定するための電気化学的特性.
- イオンペアの解離と介電スクリーニング効果の分析.
主要な成果:
- カチオンの骨格は,リ+塩イオンペアを効果的に遮断し,自由リ+イオン濃度を増加させます.
- 70 °Cで2.09 × 10^-4 S cm^-1までの有意なLi+伝導性を達成した.
- 液体溶媒がない状態で高いイオン伝導性を証明した.
結論:
- カチオン骨格をCOFに組み込むことは,固体電解質のLi+伝導性を高めるための効果的な戦略です.
- 開発されたCOF材料は,先進的な固体リチウムイオン電池で使用する可能性を示している.
- このアプローチは,従来のCOFベースの電解体のイオンペアリングの限界を克服します.
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