文献类型：期刊文献

英文题名：Investigation into the thermal decomposition behavior and kinetics mechanism of Li2SiF6

作者：Hu, Chuanhang Tang, Shiyun Cai, Cheng Dang, Ziwei Chen, Huanhuan Xiao, Miao An, Zhengyu Tang, Anjiang

第一作者：Hu, Chuanhang

通信作者：Tang, AJ[1]

机构：[1]Guizhou Univ, Coll Chem & Chem Engn, Guiyang 550025, Peoples R China;[2]Guizhou Inst Technol, Guiyang 550025, Peoples R China

第一机构：Guizhou Univ, Coll Chem & Chem Engn, Guiyang 550025, Peoples R China

通信机构：corresponding author), Guizhou Inst Technol, Guiyang 550025, Peoples R China.|贵州理工学院;

年份：2026

卷号：760

外文期刊名：THERMOCHIMICA ACTA

收录：;EI(收录号：20261420433120);Scopus(收录号：2-s2.0-105034730769);WOS:【SCI-EXPANDED(收录号:WOS:001733226000001)】；

基金：The authors gratefully acknowledge the financial support from the Science and Technology Planning Project of Guizhou Province (Qiankehezhicheng [2021] Yiban 493 and Qiankehejichu-ZK [2023] Yiban 129) , Guizhou Institute of Technology Educational Teaching Reform Project (JGYB202414) , Guizhou Institute of Technology University-level First-Class Projects (2024YLXM17) , Guizhou Institute of Technology High-Level Talent Research Start-Up Funding Program (2023GCCZK) .

语种：英文

外文关键词：Thermal decomposition kinetics; Coats-Redfern method; Criado method; Li2SiF6

摘要：This study investigates the thermal decomposition behavior and kinetic model mechanism of lithium hexafluorosilicate (Li2SiF6). Fourier Transform Infrared (FTIR) spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy (SEM) were utilized to characterize both the solid and gaseous products generated during the thermal decomposition of Li2SiF6. Multi-heating-rate TG experiments were carried out at 5, 10, and 20 degrees C/ min, and the apparent activation energies were evaluated by the FWO, KAS, and Starink isoconversional methods. The average activation energies obtained by the three methods were close to each other, indicating good reliability of the kinetic analysis. On this basis, the Coats-Redfern curve-fitting technique, applied through Matlab software, was used to fit 16 common solid-phase reaction mechanism models to determine the reaction mechanism for the thermal decomposition of Li2SiF6. The reaction order, activation energy (Ea), and pre-exponential factor (A) for the primary decomposition stages were calculated. The results show that, under an argon atmosphere, Li2SiF6 completely decomposes into LiF and SiF4 after calcination at 350 degrees C for 30 min. The validity of the Coats-Redfern method was further confirmed by comparing theoretical models to experimental curves derived from the Criado method. Kinetic analysis suggests that the thermal decomposition of Li2SiF6 follows a three-dimensional phase-interface reaction mechanism, consistent with the shrinking sphere model, with an activation energy of 152.07 kJ/mol. This study provides important thermodynamic and kinetic reference data for the further application of Li2SiF6 in lithium-ion battery electrolytes and the preparation of fluorides.