Nanoheterogeneity of LiTFSI Solutions Transitions Close to a Surface and with Concentration
Nanoheterogeneity of LiTFSI Solutions Transitions Close to a Surface and with Concentration
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DOI：
10.1021/acs.nanolett.1c00167
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发表时间：
2021-02-22
期刊：
影响因子：
10.8
通讯作者：
Espinosa-Marzal, Rosa M.
中科院分区：
文献类型：
--
作者：
Han, Mengwei;Zhang, Ruixian;Espinosa-Marzal, Rosa M.
由21 m LiTFSI组成的盐包水（WIS）电解质最近已成为锂离子电池中常规有机电解质的安全且环保的替代品。一些研究强调了WIS电解质的高电导率与其纳米级结构之间的关系。结合力的测量与表面力装置和原子力显微镜，本研究描述了纳米异质性的LiTFSI解决方案的浓度和距离的函数从带负电荷的（云母）表面。我们报告各种纳米结构共存于WIS电解质，其大小随浓度增加，并受到云母表面的接近。确定了两个关键的浓度阈值，超过该阈值，观察到行为的转变。对浓度依赖性纳米结构的仔细研究为设计未来储能器件中的新型电解质奠定了基础。
Water-in-salt (WIS) electrolytes composed of 21 m LiTFSI have recently emerged as a safe and environmentally friendly alternative to conventional organic electrolytes in Li-ion batteries. Several studies have emphasized the relation between the high conductivity of WIS electrolytes and their nanoscale structure. Combining force measurements with a surface forces apparatus and atomic force microscopy, this study describes the nanoheterogeneity of LiTFSI solutions as a function of concentration and distance from a negatively charged (mica) surface. We report various nanostructures coexisting in the WIS electrolyte, whose size increases with concentration and is influenced by the proximity of the mica surface. Two key concentration thresholds are identified, beyond which a transition of behavior is observed. The careful scrutinization on the concentration-dependent nanostructures lays groundwork for designing novel electrolytes in future energy storage devices.