Spindle-like Fe7S8/C anchored on S-doped graphene nanosheets as a superior long-life and high-rate anode for lithium-ion batteries

Abstract

Transition metal sulfide, as a highly anticipated anode material for high performance lithium-ion batteries (LIBs). Ingenious structural design and reasonable surface modification are used to inhibit the volume expansion of transition metal sulfide during cycling and improve its specific capacity. In this work, a spindle-like Fe7S8/C@rGO composite was synthesized by two-step hydrothermal method. The prepared anode material shows superior electrochemical properties and extraordinary electrical conductivity. Which delivering a considerable specific capacity of 1465.1 mAh g−1 at 0.1A g−1 after 150 cycles and an impressively long cycle life with a capacity of 689.4 mAh g−1 at 1 A g−1 after 100 cycles. These satisfactory performances are attributed to the special nanostructure and the addition of rGO. In addition, the pseudocapacitive behavior effectively increases the extra reversible capacity of Fe7S8/C@rGO. This practical synthesis strategy provides a novel way to pursue extraordinary performance anode materials for lithium-ion batteries.