Solvothermal Synthesis of Co₃S₄/Graphene Nanoassemblies As Anode Materials for Lithium-Ion Batteries

Co₃S₄/graphene nanoassemblies were synthesized by a facile solvothermal approach, in which bifunctional dimethyl sulfoxide served as both solvent and sulfur-source. Structural characterizations reveal an intimate contact between Co₃S₄ and graphene matrix. When employed as anode materials for lithium-ion batteries, the Co₃S₄/graphene nanoassemblies exhibited good electrochemical performance, including a high reversible capacity of 1085 mAh/g, good cyclability and excellent rate capability. Compared to bare Co₃S₄ and graphene, the lithium-ion storage performance has been significantly improved. The improved electrochemical performance for reversible lithium-ion storage could be ascribed to the synergistic effects of the Co₃S₄/graphene nanoassemblies as an integrated hybrid nanoarchitecture, in which graphene nanosheets provide electronic conductivity, serve as the homogeneous dispersive agent and offer buffer layers for the active Co₃S₄ during lithium-ion insertion and extraction processes.