Liquid-Solid-Solution Assembly of CoFe2O4/Graphene Nanocomposite as a High-Performance Lithium-Ion Battery Anode

Abstract

CoFe2O4/graphene composites were fabricated via a novel one-pot liquid-solid-solution (LSS) hydrothermal process. Through ions electrostatic adsorption onto graphene sheets and oil microemulsion encapsulation, CoFe2O4 nanoparticles can be uniformly anchored on crumpled graphene sheets without aggregation, and the size distribution of CoFe2O4 particles can be controlled by the microemulsion shell in the range of 50–100nm. With the synergistic effect between CoFe2O4 and graphene, the CoFe2O4/graphene hybrid exhibits a high reversible specific capacity of 1102mAhg−1 at 0.2Ag−1 after 100 cycles, and a good cycling stability as well. Moreover, the composite has good rate capability. The specific capacity can reach a high value of 410mAhg−1 even under a high current density of 6.4Ag−1 (corresponds to a charge time of ∼230s), indicating its promising application as an anode material for lithium ion batteries.