パルフオロスルフォニック酸の陽子伝導膜における構造とリラクゼーションの相互作用
Guinevere A Giffin1, Gregory M Haugen, Steven J Hamrock
1Department of Chemical Sciences, University of Padova, Via Marzolo 1, I-35131 Padova, Italy.
Journal of the American Chemical Society
|December 20, 2012
まとめ
この研究は,等価重量 (EW) によって影響されるイオノマー膜構造が,性質にどのように影響するかを明らかにしています. より高いEW膜は,陽子交換の制限が増加し,導電性に影響します.
科学分野:
- マテリアルサイエンス 材料科学
- 電気化学 電気化学について
- ポリマーサイエンスの科学
背景:
- イオノマー膜は,燃料電池の性能にとって極めて重要です.
- 構造-特性関係を理解することは,膜設計を最適化するための鍵です.
研究 の 目的:
- 異なる重量相当 (EW) の3Mイオノマー膜の構造変化を調査する.
- これらの構造的変化と膜の特性,特に導電性を相関させる.
主な方法:
- 膜構造を分析するための広角X線 difraktion (WAXD).
- 振動スペクトロスコーピーは,化学的変化と水の相互作用を研究するために使用されます.
- 性能を評価するために,高温での導電性測定.
主要な成果:
- 膜 (700 EWを除く) で観察された有序な水害性領域.
- 陽子の解離と,EWと水分量に関連したポリ (テトラフルオロエチレン) ドメインの結晶性の変化.
- 導電性はVogel-Tammann-Fulcher (VTF) 行動に従っており,異地化体 (DBs) 経由で陽子の移動を示しています.
- より小さなEW膜は,より大きな界面伝導率の貢献を示し,より大きなEW膜はDB陽子交換に依存する.
結論:
- 膜構造は陽子の伝導性に大きく影響する.
- DBsの間の陽子交換は,より高いEWsで速度制限になります.
- イオノマー膜構造の最適化は,燃料電池の効率的な動作に不可欠です.
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