Fe₃S₄ Nanoparticles Wrapped in an rGO Matrix for Promising Energy Storage: Outstanding Cyclic and Rate Performance

Iron sulfides/oxides/fluorides have been profoundly investigated as electrodes for rechargeable batteries recently in view of their high-theory capacities, low cost, and environmentally benign nature. Here, Fe₃S₄ nanoparticles (NPs) wrapped in reduced graphene oxide (Fe₃S₄ NPs@rGO) have been obtained using a simple one-pot hydrothermal approach, which is characterized using various techniques. As the anode for Li-ion batteries, Fe₃S₄ NPs@rGO displays a reversible discharge capacity of 950 mA h/g after 100 cycles at 0.1 A/g, and 720 mA h/g capacity can be achieved after 800 cycles even at 1 A/g. Even at 10 A/g, 462 mA h/g capacity can be maintained. The excellent electrochemical properties for Fe₃S₄ NPs@rGO can be ascribed to a collaborative effect between Fe₃S₄ NPs and an rGO matrix, which possess high Li-ion storage ability and excellent conductivity, respectively.