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

A self-supporting Co 3 O 4 /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, Co 3 O 4 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 Co 3 O 4 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).