FeS under wrinkled thin-layer carbon derived from ionic liquid as a high-performance sodium-ion battery anode material

FeS is a promising anode material with high theoretical capacity in sodium-ion batteries (SIBs). Unfortunately, the unstable structure and poor conductivity of FeS limit its commercial applications. Herein, FeS coated by wrinkled thin layers of carbon (FeS/C) is synthesized by using a simple pyrolysis strategy. The wrinkled carbon layers, which derived from ionic liquids, effectively improve the conductivity and structural stability of FeS. When employed as anode in SIBs, FeS/C exhibits high capacity, long cycle life, and excellent stability. Specifically, when the current density is 0.1 A g?1 and 0.5 A g?1, the reversible capacity of FeS/C reaches 404.7 mAh g?1 and 304.8 mAh g?1 after 100 cycles. When the current density increases to 4 A g?1, the sodium storage can maintain a capacity of 178.8 mAh g?1 after 1000 cycles. The excellent electrochemical performance can be attributed to the wrinkled carbon layers that enhance the structural stability and charge mobility.

Automated summary

FeS/C, synthesized by a simple pyrolysis strategy, shows high capacity, long cycle life, and stability in sodium-ion batteries, attributed to the wrinkled carbon layers enhancing structural stability and charge mobility.