Cs7(H4PO4) の構造と特性 (H2PO4) 8:珍しいポリケーション (H4PO4) を特徴とする新しい超陽子固体酸
Louis S Wang1, Sawankumar V Patel2, Sheel S Sanghvi1
1Materials Science & Engineering, Northwestern University, 2220 Campus Drive, Evanston, Illinois 60208, United States.
Journal of the American Chemical Society
|November 12, 2020
まとめ
新しい超プロトン導体Cs7 (H4PO4) (H2PO4) 8 (CPP) が発見されました これはCsH2PO4より低い温度で形成されます この材料は乾燥条件下でも安定性があり,プロトン輸送アプリケーションに広大な運用窓を提供します.
科学分野:
- 固体化学
- 材料科学
- プロトンの伝導性
背景:
- 超プロトン伝導体は エネルギー利用に不可欠です
- セシウム二酸化水素 (CsH2PO4) は,228 °C以上では超プロトン的行動を示す.
- 移行温度が低い新しい超プロトン材料の開発は望ましい.
研究 の 目的:
- 新しい超陽子化合物の発見と特徴を報告する
- この新相の構造,熱力学,陽子輸送の性質を調査する.
- 陽子伝導性を要求するアプリケーションの可能性を探求する.
主な方法:
- 高温単結晶のX線 difraksionで
- 高温 31P NMR スペクトル
- CsH2PO4とCsH5 ((PO4) 2) の反応による合成
主要な成果:
- 新しい超陽子化合物であるCs7 (H4PO4) (H2PO4) 8 (CPP) の発見.
- CPPは,空間群P m-3 nでユニークなH4PO4+カチオンで結晶化する.
- CPPは90 °Cで形成され,乾燥状態では151 °Cまで安定し,中程度の陽子伝導性 (140 °Cで5.8 × 10-4 S cm-1) を表しています.
結論:
- 新型H4PO4+カチオンは,CPPの特性に大きな影響を与える.
- CPPは,CsH2PO4と比較して,乾燥状態での超プロトン伝導のためのより広い安定範囲を提供します.
- この材料は,形成温度が低く脱水安定性があるため,固体プロトン装置の可能性を示しています.
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