単層ナノ封じられた水の第一原理相図
Venkat Kapil1, Christoph Schran2,3,4, Andrea Zen5,6
1Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK. vk380@cam.ac.uk.
Nature
|September 14, 2022
まとめ
ナノ限られた水は,新しい固体,液体,超イオン状態を含む複雑な相行動を示す. この発見は ナノスケールで水を制御することで 先進的な材料と技術への道を開きます
科学分野:
- 物理化学
- 材料科学
- ナノテクノロジー
背景:
- ナノスケールでの水の性質は 大量の水と比較して 大きく異なります
- 異常な行動には,低圧電定数,摩擦のない流れ,およびユニークな氷相が含まれます.
- ナノコンフィネッド水はナノ流体,電解質,脱塩化における応用の可能性を持っています.
研究 の 目的:
- グラフェンのようなチャネル内の1つの層に閉じ込められた水の分子レベルの行動を調査する.
- ナノコンフィネスされた水の 豊かな様相性を理解するためです
- 技術の応用のためにナノコンフィネッドウォーターのエンジニアリングの可能性を調査する.
主な方法:
- 計算方法の組み合わせを用いて最初の原則レベルの調査を行いました.
- グラフェンのようなナノチャネルで 単一の水層をシミュレートした
- 温度とヴァン・デル・ワールスの圧力条件の変動下で分析された相性.
主要な成果:
- 温度と圧力に非常に敏感な単層の水における多様な相性を発見した.
- 圧力 (>400K範囲) で単調に変化しない融点を持つ複数の分子相を特定した.
- 固体と液体の間のヘクサティック・フェーズと,高い電気伝導性を有するスーパーイオン・フェーズの存在を予測した.
結論:
- ナノコンフィニメントは水の中で驚くほど豊かで調節可能な相性を誘導します
- 予測された超音波相は,現在のバッテリー材料よりも優れた伝導性を示す.
- ナノ・コンフィニメントは 入手可能な条件下で 超音波の振る舞いを達成する 実行可能な経路を提供します
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