Self-supporting Co3O4/Graphene Hybrid Films as Binder-free Anode Materials for Lithium Ion Batteries

Abstract

A self-supporting Co3O4/graphene hybrid film has been constructed via vacuum filtration of Co(OH)2 nanosheet and graphene, followed by a two-step thermal treatment. Within the hybrid film, Co3O4 nanoparticles with size of 40∼60 nm uniformly in-situ grew on the surface of graphene, forming a novel porous and interleaved structure with strong interactions between Co3O4 nanoparticles and graphene. Such fascinating microstructures can greatly facilitate interfacial electron transportation and accommodate the volume changes upon Li ions insertion and extraction. Consequently, the binder-less hybrid film demonstrated extremely high reversible capacity (1287.7 mAh g -1 at 0.2 A g -1), excellent cycling stability and rate capability (1110 and 800 mAh g -1 at 0.5 and 1.0 A g -1, respectively).