文献类型：期刊文献

英文题名：Hierarchical porous carbon nanofibers embedded with ultrafine Nb2O5 nanocrystals for polysulfide-trapping-conversion Li-S batteries

作者：Fang, Minxiang[1];Huang, Qigang[1];Ma, Lianbo[2];Xu, Jie[2];Kang, Qi[3];Cao, Yongjie[4];Hu, Shuozhen[1];Zhang, Xinsheng[1];Niu, Dongfang[1]

机构：[1]East China Univ Sci & Technol, Sch Chem Engn, State Key Lab Chem Engn, Shanghai 200237, Peoples R China;[2]Anhui Univ Technol, Sch Mat Sci & Engn, Maanshan 243002, Peoples R China;[3]Shanghai Jiao Tong Univ, Dept Polymer Sci & Engn, Shanghai Key Lab Elect Insulat & Thermal Ageing, Shanghai 200240, Peoples R China;[4]Fudan Univ, Inst New Energy, Dept Chem, Shanghai Key Lab Mol Catalysis & Innovat Mat, Shanghai 200433, Peoples R China

年份：2022

卷号：434

外文期刊名：ELECTROCHIMICA ACTA

收录：;EI(收录号：20224212900588);WOS:【SCI-EXPANDED(收录号:WOS:000930651800005)】；

基金：This work was financially supported by the National Natural Science Foundation of China (No. 21972042) and the National Key R & D Pro- gram of China (No. 2017YFB0307502) .

语种：英文

外文关键词：Li-S batteries; Separator; Hierarchical porous structure; Polysulfide trapping

摘要：The practical application of lithium-sulfur (Li-S) batteries is severely impeded by the sluggish redox kinetics and polysulfides shuttling. Herein, hierarchical porous carbon nanofibers (HPCNF) embedded with ultrafine Nb2O5 nanocrystals (denoted as Nb2O5-HPCNF) are designed and served as a duplex-functional separator for polysulfide trapping and kinetic enhanced Li-S batteries. The hierarchical porous structure serves as a reservoir for polysulfide trapping, and HPCNF network provides channels for fast electron/ion transport. More importantly, the built-in Nb2O5 nanocrystals enhance the chemical affinity of polysulfides, and simultaneously promote the liquid-solid conversions of polysulfides. As a result, the Li-S batteries with Nb2O5-HPCNF separator delivered a high initial capacity of 1393 mAh g-1 at 0.2 C and a high capacity of 741 mAh g-1 even at 4.0 C. Moreover, the modified cell can remain 574 mAh g-1 after 600 cycles at 1.0 C, corresponding to an ultralow decay rate of 0.066% per cycle. This work provides a rational design for achieving high-performance Li-S batteries.