In situ incorporation of FeS nanoparticles/carbon nanosheets composite with an interconnected porous structure as a high-performance anode for lithium ion batteries

Abstract

Interconnected porous FeS/C composite consisting of FeS nanoparticles (∼20 nm) homogeneously embedded in carbon nanosheets was synthesized via a facile freeze-drying/carbonization method using a NaCl template. As an anode for LIBs, this composite shows significantly enhanced electrochemical performance due to the synergistic effects of the conductive carbon film and the porous structure, which provides an ideal conductive matrix and buffer spaces for electron/ion transfer and FeS expansion, respectively, during lithiation processes. This composite exhibits reversible capacities of ∼703 mA h g⁻¹ over 150 cycles at 1 A g⁻¹ and a high-rate capability of ∼530 mA h g⁻¹ even at 5 A g⁻¹, which is among the best reported electrochemical performances for FeS-based materials thus far. With a long cycling life and high power density, this composite demonstrates its potential application in LIBs.