Highly active Fe_(7)S_(8) encapsulated in N-doped hollow carbon nanofibers for high-rate sodium-ion batteries

作     者：Chengzhi Zhang Donghai Wei Fei Wang Guanhua Zhang Junfei Duan Fei Han Huigao Duan Jinshui Liu Chengzhi Zhang;Donghai Wei;Fei Wang;Guanhua Zhang;Junfei Duan;Fei Han;Huigao Duan;Jinshui Liu

作者机构：Hunan Province Key Laboratory for Advanced Carbon Materials and Applied TechnologyCollege of Materials Science and EngineeringHunan UniversityChangsha 410082HunanChina State Key Laboratory of Advanced Design and Manufacturing for Vehicle BodyCollege of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082HunanChina School of Materials Science and EngineeringChangsha University of Science and TechnologyChangsha 410004HunanChina 

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

年 卷 期：2021年第30卷第2期

页      面：26-35,I0002页

核心收录：

学科分类：081702[工学-化学工艺] 0808[工学-电气工程] 08[工学] 0817[工学-化学工程与技术] 

基　　金：financial support from the National Natural Science Foundation of China (Grant No. 51702095) the Natural Science Foundation of Hunan Province, China (Grant No. 2018JJ3041, 2018JJ3042) the funding of State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body in Hunan University (No. 51965010) 

主　　题：Sodium-ion batteries Anode High rate Iron sulfides N-doped hollow carbon fibers 

摘      要：Nanostructured iron sulfides are regarded as a potential anode material for sodium-ion batteries in virtue of the rich natural abundance and remarkable theoretical ***,poor rate performance and inferior cycling stability caused by sluggish kinetics and volume swelling represent two main obstacles at present. The previous research mainly focuses on nanostructure design and/or hybridizing with conductive *** boosting the property by adjusting Fe/S atomic ratio in iron sulfides is rarely *** this work,Fe_7 S_8 and FeS_2 encapsulated in N-doped hollow carbon fibers(NHCFs/Fe_7 S_8 and NHCFs/FeS_2) are constructed by a combined chemical bath deposition and subsequent sulfidation *** well-designed NHCFs/Fe_(7) S_(8) electrode displays a remarkable capacity of 517 mAh g^(-1) at 2 A g^(-1)after 1000 cycles and a superb rate capability with a capability of 444 mAh g^(-1) even at 20 A g^(-1) in etherbased ***,the rate capability of NHCFs/Fe_(7) S_(8) is superior to that of the contrast NHCFs/FeS_(2) electrode and also much better than the values of the most previously reported iron sulfide-based *** in-depth mechanism explanation is explained by further experimental analysis and theoretical calculation,revealing Fe_(7) S_(8) displays improved intrinsic electronic conductivity and faster Na^(+) diffusion coefficient as well as higher reaction reversibility.