Understanding fluorine-free electrolytes via small-angle X-ray scattering

作     者：Kun Qian Zhou Yu Yuzi Liu David J.Gosztola Randall E.Winans Lei Cheng Tao Li Kun Qian;Zhou Yu;Yuzi Liu;David J.Gosztola;Randall E.Winans;Lei Cheng;Tao Li

作者机构：Department of Chemistry and BiochemistryNorthern Illinois UniversityDeKalbIL 60115USA Materials Science Division and Joint Center for Energy Storage ResearchArgonne National LaboratoryLemontIL 60439USA Center for Nanoscale MaterialsArgonne National LaboratoryLemontIL 60439USA X-ray Science Division and Joint Center for Energy Storage ResearchArgonne National LaboratoryLemontIL 60439USA 

出 版 物：《Journal of Energy Chemistry》 (能源化学（英文版）)

年 卷 期：2022年第31卷第7期

页      面：340-346,I0009页

核心收录：

学科分类：0808[工学-电气工程] 081704[工学-应用化学] 08[工学] 0817[工学-化学工程与技术] 0805[工学-材料科学与工程（可授工学、理学学位）] 0703[理学-化学] 

基　　金：supported as part of the Joint Center for Energy Storage Research,an Energy Innovation Hub funded by the U.S.Department of Energy,Office of Science,Basic Energy Sciences the supported by U.S.National Science Foundation(Grant No.2120559) 

主　　题：Fluorine-free electrolytes Sodium-ion batteries Small-angle X-ray scattering Solvation structures Sodium tetraphenylborate 

摘      要：Fluorine-free electrolytes have attracted great attention because of its low-cost and environmental friendliness. However, so far, little is known about the solution structures of these electrolytes. Here,we compare the solvation phenomenon of sodium tetraphenylborate(NaBPh_(4)) salt dissolved in organic solvents of propylene carbonate(PC), 1,2-dimethoxyethane(DME), acetonitrile(ACN) and tetrahydrofuran(THF). Small-angle X-ray scattering(SAXS) reveals a unique two-peak structural feature in this saltconcentrated PC electrolyte, while solutions using other solvents only have one scattering *** dynamics(MD) simulations further reveal that there are anion-based clusters in addition to the short-range charge ordering in the concentrated NaBPh4/PC electrolyte. Raman spectroscopy confirms the existence of considerable contact ion pairs(CIPs). This work emphasizes the importance of global and local structural analysis, which will provide valuable clues for understanding the structureperformance relationship of electrolytes.