Cobalt‐Doped FeS2 Nanospheres with Complete Solid Solubility as a High‐Performance Anode Material for Sodium‐Ion Batteries. (14th September 2016)

• Record Type: Journal Article
• Authors: Zhang, Kai; Park, Mihui; Zhou, Limin; Lee, Gi‐Hyeok; Shin, Jeongyim; Hu, Zhe; Chou, Shu‐Lei; Chen, Jun; Kang, Yong‐Mook
• Is Part Of: Angewandte Chemie. Volume 128:Number 41(2016)
• Page Start: 13014
• Page End: 13018
• Publication Date: 2016-09-14
• Subjects: Anodenmaterialien -- Cobaltdotiertes Eisensulfid -- Feste Lösungen -- Natriumionenbatterien; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.201607469
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: Considering that the high capacity, long‐term cycle life, and high‐rate capability of anode materials for sodium‐ion batteries (SIBs) is a bottleneck currently, a series of Co‐doped FeS2 solid solutions with different Co contents were prepared by a facile solvothermal method, and for the first time their Na‐storage properties were investigated. The optimized Co0.5 Fe0.5 S2 (Fe0.5) has discharge capacities of 0.220 Ah g −1 after 5000 cycles at 2 A g −1 and 0.172 Ah g −1 even at 20 A g −1 with compatible ether‐based electrolyte in a voltage window of 0.8–2.9 V. The Fe0.5 sample transforms to layered Na x Co0.5 Fe0.5 S2 by initial activation, and the layered structure is maintained during following cycles. The redox reactions of Na x Co0.5 Fe0.5 S2 are dominated by pseudocapacitive behavior, leading to fast Na + insertion/extraction and durable cycle life. A Na3 V2 (PO4 )3 /Fe0.5 full cell was assembled, delivering an initial capacity of 0.340 Ah g −1 .