| Affiliation: | 1. State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050 China
Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049 China;2. Laboratory of Advanced Materials, Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai, 200438 China;3. School of Mechanical and Electrical Engineering, Jingdezhen Ceramic Institute, Jingdezhen, 333403 China;4. State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050 China |
| Abstract: | Alloying-type metal sulfides with high theoretical capacities are promising anodes for sodium-ion batteries, but suffer from sluggish sodiation kinetics and huge volume expansion. Introducing intercalative motifs into alloying-type metal sulfides is an efficient strategy to solve the above issues. Herein, robust intercalative In S motifs are grafted to high-capacity layered Bi2S3 to form a cation-disordered (BiIn)2S3, synergistically realizing high-rate and large-capacity sodium storage. The In S motif with strong bonding serves as a space-confinement unit to buffer the volume expansion, maintaining superior structural stability. Moreover, the grafted high-metallicity Indium increases the bonding covalency of Bi S, realizing controllable reconstruction of Bi S bond during cycling to effectively prevent the migration and aggregation of atomic Bi. The novel (BiIn)2S3 anode delivers a high capacity of 537 mAh g−1 at 0.4 C and a superior high-rate stability of 247 mAh g−1 at 40 C over 10000 cycles. Further in situ and ex situ characterizations reveal the in-depth reaction mechanism and the breakage and formation of reversible Bi S bonds. The proposed space confinement and bonding covalency enhancement strategy via grafting intercalative motifs can be conducive to developing novel high-rate and large-capacity anodes. |
