聚乙三甲) - - 聚乙) - - 电化学应用膜中的基密度和放松之间的相互作用
Keti Vezzù1,2, Ashley M Maes3, Federico Bertasi1,4
1Section of Chemistry for Technology, Department of Industrial Engineering, University of Padova, in Department of Chemical Sciences , Via Marzolo 1, I-35131 Padova, Italy.
Journal of the American Chemical Society
|January 10, 2018
概括
分析了具有不同离子交换能力的离子交换膜 (AEM). 一个关键的转变影响了离子导电性,聚类阻碍了更高容量的膜中的传输.
科学领域:
- 聚合物科学与工程
- 材料科学
- 电化学
背景情况:
- 离子交换膜 (AEM) 在燃料电池等电化学应用中至关重要.
- 了解它们的热和电特性对于性能优化至关重要.
- 基于聚乙三甲) -b-聚甲) 的 AEM 具有可调节的特性.
研究的目的:
- 综合描述具有不同离子交换能力 (IEC) 的AEM.
- 阐明热过渡,电特性和离子导电性之间的关系.
- 提出导电机制并了解限制离子传输的因素.
主要方法:
- 高分辨率热重力测量 (HR-TGA)
- 调制差分扫描热量计 (mDSC)
- 动态机械分析 (DMA)
- 宽带电光谱 (BES)
主要成果:
- 确定了依赖于IEC的玻璃过渡 (Tg) 和乱序过渡 (Tδ).
- 电反应的特征,确定有助于极化 (σEP,σIP,1) 和介电松 (β1,β2).
- 在Tδ (>20°C) 观察到离子对双极重排,导致显著的离子导电率下降;聚类影响更高的IEC膜.
结论:
- 对于AEM,建议采用双导电路机制 (σEP和σIP,1).
- 障碍 - 顺序过渡 (Tδ) 通过重新排序双极显著影响离子导电性.
- 在高IEC膜中聚集阻碍了有效的离子传输,突出了AEM设计的关键因素.
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