通过电化学驱动的离子注入到合聚合物中的可逆结构相位过渡
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
概括
结合聚合物在电化学循环过程中表现出可逆的结构相变. 这种独特的行为使得聚[2,5-bis(thiophenyl)-1,4-bis(2-(2-methoxyethoxy) ethoxy) benzene] (PB2T-TEG) 能够进行非Fickian离子传输,这对于储能至关重要.
科学领域:
- 材料科学
- 聚合物化学
- 电化学
背景情况:
- 结合聚合物对电化学能量储存具有前景.
- 了解它们在离子运输过程中的结构动态对于性能至关重要.
- 之前的研究表明,在类似的材料中,Fickian扩散.
研究的目的:
- 在电化学循环过程中研究糖化合聚合物 (PB2T-TEG) 的结构相变.
- 阐明这些转换对离子-极子对传输的影响.
- 探索能量存储和神经形态计算的潜在应用.
主要方法:
- 用宽角X射线散射 (GIWAXS) 来分析晶体相.
- 在水性电解质中进行电化学氧化和离子注入.
- 使用光学显微镜和超分辨率光诱导力显微镜 (PiFM) 的移动前端实验.
主要成果:
- 在电化学氧化/还原过程中,PB2T-TEG经历可逆的结构相变.
- 这些转换导致具有尖配置的非Fickian离子-极子对运输.
- 运输行为与在P3MEEMT等其他聚合物中观察到的Fickian扩散形成鲜明对比.
结论:
- 在PB2T-TEG中观察到的结构相变与LiFePO4等无机材料的相变相似.
- 结合聚合物的相似相位过渡特性可以增强电化学能量存储和神经形态记忆应用.
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