文献类型：期刊文献

英文题名：Synergic effect of covalent and chemical sulfur fixation enhancing the immobilization-conversion of polysulfides in lithium-sulfur batteries

作者：Gao, Ruili Zhang, Qian Wang, Hui Wang, Fanghui Ren, Jianwei Wang, Xuyun Ma, Xianguo Wang, Rongfang

第一作者：Gao, Ruili

通信作者：Wang, H[1];Wang, RF[1];Ren, JW[2]

机构：[1]Qingdao Univ Sci & Technol, Coll Chem Engn, State Key Lab Base Ecochem Engn, Qingdao 266042, Shandong, Peoples R China;[2]Weifang Vocat Coll, Sch Chem & Engn, Weifang 261108, Shandong, Peoples R China;[3]Univ Johannesburg, Dept Mech Engn Sci, Cnr Kingsway & Univ Rd,Auckland Pk, ZA-2092 Johannesburg, South Africa;[4]Guizhou Inst Technol, Sch Chem Engn, Guiyang 550003, Guizhou, Peoples R China

第一机构：Qingdao Univ Sci & Technol, Coll Chem Engn, State Key Lab Base Ecochem Engn, Qingdao 266042, Shandong, Peoples R China

通信机构：corresponding author), Qingdao Univ Sci & Technol, Coll Chem Engn, State Key Lab Base Ecochem Engn, Qingdao 266042, Shandong, Peoples R China;corresponding author), Univ Johannesburg, Dept Mech Engn Sci, Cnr Kingsway & Univ Rd,Auckland Pk, ZA-2092 Johannesburg, South Africa.

年份：2023

卷号：79

起止页码：1-11

外文期刊名：JOURNAL OF ENERGY CHEMISTRY

收录：;EI(收录号：20230413442599);Scopus(收录号：2-s2.0-85146694566);WOS:【SCI-EXPANDED(收录号:WOS:000924205200001)】；

基金：Acknowledgments All the authors thank the financially supports from the National Natural Science Foundation of China (51963004) , and the Natural Science Foundation of Shandong Province of China (ZR2020MB024) .

语种：英文

外文关键词：Lithium-sulfur battery; Covalent sulfur-fixation; Chemical sulfur-fixation; Electrolyte additive; Cycling stability

摘要：Lithium-sulfur batteries (LSBs) are promising as the next generation energy storage options. However, their wide applications have been technically challenged by the diffusion losses of polysulfides and polysulfide shuttle effect. In this work, the small organic molecules of 2,5-dichloropyrazine (2,5-DCP) were combined with Co-doped carbon (Co-N-C) flakes to achieve the synergic effect of the covalent and chemical sulfur fixation, so as that the immobilization-conversion of polysulfides in LSBs was greatly enhanced. More specifically, the nucleophilic substitution of the 2,5-DCP additive in the electrolyte with polysulfides formed the C-S bonds. Through the further covalent N-Li bonds between the N atoms in 2,5-DCP and polysulfides, sulfur fixation was achieved in the form of solid organosulfur. Meanwhile, the Co-N-C flakes served as the sulfur cathode to chemically anchor the polysulfides. The interaction mechanism between Co-N-C/2,5-DCP and polysulfides was explored by the density functional theory (DFT) calculations and in-situ infrared spectroscopy. The results showed that the optimal "with 2,5-DCP " sample-assembled LSB exhibited an initial discharge specific capacity of 1244 mA h g(-1) at 0.2C, and a capacity decay rate of 0.053% per cycle was displayed after 800 cycles at 1C. The good cycling stability with a high sulfur-loaded electrode sample suggested that the synergic effect of covalent/chemical sulfur fixation enabled the enhancement of polysulfides immobilization-conversion in LSBs. (c) 2023 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by ELSEVIER B.V. and Science Press. All rights reserved.