聚烯二基电解质中的残留溶剂的分子结构:对导电性和稳定性的影响
Lu Lin1, Changhao Liu1, Robert L Sacci1
1Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.
The Journal of chemical physics
|November 22, 2024
概括
聚烯二 (PAN) 聚合物电解质中的残留溶剂阻碍了离子电池的性能. 使用先进的光谱学了解这些溶剂相互作用是设计更安全,更稳定的固体电解质的关键.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 频谱学是一种光谱学.
背景情况:
- 离子电池对于现代技术至关重要,但挥发性有机电解质引发了安全问题.
- 基于聚合物的固体电解质提供了一个更安全的替代品,聚烯 (PAN) 是一个有前途的耐火材料.
- 有限的PAN溶解度需要低挥发性溶剂,在加工过程中对其去除构成挑战.
研究的目的:
- 为了研究残留N,N-二甲基形式胺 (DMF) 溶剂对基于PAN的聚合物电解质的分子水平影响.
- 了解残留DMF如何影响聚合物矩阵内的离子 (Li+) 的结构和动态.
- 在固体聚合物电解质中,将溶剂含量与离子导电性和潜在稳定性问题相关联.
主要方法:
- 利用秒二维红外 (2D-IR) 光谱仪进行深入的分子分析.
- 采用线性和非线性红外光谱仪研究基于PAN的电解质,含有不同度的DMF.
- 探讨了PAN,Li+和残留的DMF之间的分子相互作用.
主要成果:
- 剩余DMF的度会影响PAN电解质内的Li+离子的协调结构.
- +协调涉及与DMF的碳基和/或胺相互作用,通过双极-双极相互作用与PAN的基组形成反平行结构.
- 在与Li+和PAN相互作用时,DMF的移动性受到显著限制,导致离子导电性降低.
结论:
- 在PAN电解质中的残留DMF阻碍了Li+的流动性和离子导电性.
- 抑制的DMF运动表明对电解质稳定性的潜在影响,包括对去除和化学分解的抵抗.
- 研究结果为优化设计和加工更安全,高性能的离子电池固体聚合物电解质提供了关键的见解.
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