結合ポリマーへの電気化学的に誘導されたイオン注入による可逆的な構造相転換
Connor G Bischak1, Lucas Q Flagg1, Kangrong Yan2
1Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, United States.
Journal of the American Chemical Society
|April 2, 2020
まとめ
結合ポリマーは,電気化学サイクル中に可逆的な構造的相転換を示します. ポリ[2,5-ビス ((thiophenyl) -1,4-ビス ((2- (((2-メトキシエトキシ)) エトキシ) ベンゼン] (PB2T-TEG) のこのユニークな行動は,エネルギー貯蔵に不可欠な非フィッキンイオン輸送を可能にします.
科学分野:
- 材料科学
- ポリマー化学
- 電気化学
背景:
- 結合ポリマーは電気化学的なエネルギー貯蔵に 有望です
- イオン輸送中の構造ダイナミクスを理解することは,性能にとって極めて重要です.
- 以前の研究では 似たような材料でフィキアン拡散が示されました
研究 の 目的:
- 電気化学サイクル中のグリコール結合ポリマー (PB2T-TEG) の構造的相転換を調査する.
- これらの移行がイオン-ポラロンペア輸送に与える影響を明らかにする.
- エネルギー貯蔵とニューロモルフィックコンピューティングの潜在的応用を探求する.
主な方法:
- 水晶相を分析するための広角X線散射 (GIWAXS).
- 電気化学的酸化と水中の電解質へのイオン注入
- 光学顕微鏡と超解像度フォト誘導力顕微鏡 (PiFM) を用いた移動フロント実験.
主要な成果:
- PB2T-TEGは電気化学的酸化/還元によって可逆的な構造的相変化を経験する.
- これらの移行は,鋭いプロファイルを持つ非フィッキンイオン-ポラロンペア輸送につながります.
- 輸送行動は,P3MEEMTのような他のポリマーで観察されたFickian拡散と対照的です.
結論:
- PB2T-TEGの観察された構造的相変異は,LiFePO4のような無機材料の相変異と類似しています.
- 結合ポリマーの類似した相変化特性は,電気化学的エネルギー貯蔵とニューロモルフィックメモリアプリケーションを向上させることができます.
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