晶体和无形序列定义的类块共聚物电解质中的形态-导电性关系
Jing Sun1, Xunxun Liao, Andrew M Minor
1Molecular Foundry, ‡Materials Sciences Division, and §Environmental Energy Technologies Division, Lawrence Berkeley National Laboratory, University of California , Berkeley, California 94720, United States.
Journal of the American Chemical Society
|September 25, 2014
概括
聚合物中的离子导电性在无形和晶体状态中是可比的,这挑战了以前关于可充电电池中的离子传输机制的假设.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物化学 聚合物化学
- 电化学 电化学 电化学
背景情况:
- 导电离子的聚合物对于可充电电池至关重要.
- 离子传输通常归因于无形,状聚合物的细分运动.
研究的目的:
- 在无形和晶体聚合物领域研究离子导电性.
- 为了比较不同物质状态的化学上相似的聚合物块中的离子运输.
主要方法:
- 通过亚单体固相合成,合成序列定义的二区块共聚类.
- 制备两个具有相同导电块但不同的无形 (pNeh) 和晶体 (pNdc) 非导电块的类似共聚类.
- 自组装成叶片形态,以创建不同的无形和晶体导电域.
主要成果:
- 含有乙烯氧的域表现出可比的离子导电性,无论是无形还是晶体.
- 导电块 (pNte) 在一个共聚类中是无形的,在另一个是晶体的,使直接比较成为可能.
- 该研究成功地创建了一个平台,用于研究具有不同晶度的类似聚合物领域中的离子运输.
结论:
- 聚合物领域的物质状态 (无形与晶体) 并不会显著影响离子导电性.
- 这一发现挑战了电池的聚合物电解质中对离子运输机制的传统理解.
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