Rational synthesis of two-dimensional G@porous FeS2@C composite as high-rate anode materials for sodium/potassium ion batteries. (1st June 2019)

• Record Type: Journal Article
• Authors: Yao, Qianqian; Zhang, Jianshuo; Shi, Xiuling; Deng, Bailu; Hou, Kun; Zhao, Yi; Guan, Lunhui
• Is Part Of: Electrochimica acta. Volume 307(2019)
• Page Start: 118
• Page End: 128
• Publication Date: 2019-06-01
• Subjects: FeS2 -- Graphene -- Anode material -- Sodium-ion batteries -- Potassium-ion batteries; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2019.03.184
• Languages: English
• ISSNs: 0013-4686

Abstract

Abstract: Pyrite (FeS2 ) with the advantages of high capacity, low cost and environmental benign has been considered as a promising anode material for alkali metal (Li, Na, K) ion batteries. However, the large volume expansion and its semiconductor nature result in poor battery performance and hamper its practical applications. To overcome these drawbacks, we rationally construct a two-dimensional FeS2 -carbon architecture, from which porous FeS2 nanoparticles are distributed within reduced graphene oxide matrix and carbon coating shell with abundant interior void space. Benefiting from its structure properties with conductive carbon network, protective carbon layer, and interior void room, as-prepared rGO@p-FeS2 @C composite displays superior electrochemical performance as anode materials for sodium/potassium ion batteries. For sodium storage, it exhibits good cyclic performance with a high capacity 598 mA h g −1 sustained after 100 cycles at 0.1 A g −1, and excellent rate capability (428 mA h g −1 at 10 A g −1 ). For potassium storage, it also maintains a superior rate capacity of 298 mA h g −1 at 2 A g −1 . Moreover, pseudocapacity has been proved to be dominated in charge/discharge process, accounting for the excellent rate performance. Graphical abstract: Image 1 Highlights: A unique G@p-FeS2 @C composite is synthesized by encapsulating porous FeS2 within graphene matrix and carbon coating layer. It delivered high capacities and excellent rate capabilities for sodium and potassium storage. The superior performance stems from the small FeS2, conductive network, protective carbon layer, and interior void space.