High-Performance Anode Materials with Superior Structure of Fe3O4/FeS/rGO Composite for Lithium Ion Batteries

In this work, we developed a simple one-step hydrothermal method to successfully prepare Fe3O4/FeS-reduced graphene oxide (Fe3O4/FeS/rGO) composite directly, which is a novel Lithium-ion batteries (LIBs) anode material. The characterization of Fe3O4/FeS/rGO composite demonstrates that octahedral Fe3O4/FeS particles are uniformly deposited on the rGO, leading to a strong synergy between them. The excellent structural design can make Fe3O4/FeS/rGO composite to have higher reversible capacity (744.7 mAh/g at 0.1 C after 50 cycles), excellent cycling performance and superior rate capability. This outstanding electrochemical behavior can be attributed to the conductivity network of rGO, which improves the composite electrode conductivity, facilitates the diffusion and transfer of ions and prevents the aggregation and pulverization of Fe3O4/FeS particles during the charging and discharging processes. Moreover, the Fe3O4/FeS/rGO electrode surface is covered with a thin solid-electrolyte interface (SEI) film and the octahedral structure of Fe3O4/FeS particles is still clearly visible, which indicates that composite electrode has excellent interface stability. We believe that the design of this composite structure will provide a new perspective for the further study of other transition metal oxides for LIBs.