High performance sodium-ion anodes based on FeSb2S4/Sb embedded within porous reduced graphene oxide/carbon nanotubes matrix

Abstract

Sodium-ion battery (SIB) is considered as the most likely representative battery to replace lithium-ion battery (LIB). FeSb2S4 is a promising anode material for SIB with high theoretical capacity and excellent cyclic stability. Nevertheless, Our previous studies have shown that the electrochemical performance of FeSb2S4 was strongly affected by the crystal phase, composition and structural morphology. Therefore, it is meaningful to optimize the electrochemical performance of FeSb2S4 towards practical applications. Herein, FeSb2S4/Sb/rGO powder with high reversible capacity and improved capacity retention ratio was fabricated by using FeSb2S4 compounded with Sb and rGO. Upon assembling the FeSb2S4/Sb/rGO powder into 3D discs using the CNTs and rGO as high conductive networks, physical properties of FeSb2S4/Sb/rGO disc showed that the depositional phase of FeSb2S4 and Sb uniformly distributed in highly porous carbon networks. Electrochemical test results revealed that a high reversible area-specific and mass-specific capacity of 1.2 mAh cm−2 and 174.9 mAh g−1 can be obtained for the FeSb2S4/Sb/rGO disc with 1.1 mm thickness at 50 cycles and 1.0 A g−1. This work provides a new strategy for the design of semi-conductive anodes with high-performance for SIB applications.