Graphene oxides-guided growth of ultrafine Co3O4 nanocrystallites from MOFs as high-performance anode of Li-ion batteries

This work presents the self-assembly growth of metal organic frameworks (ZIF-67) dodecahedrons on graphene oxides (GO) nanosheets. Ultrafine Co3O4 nanocrystallites with size of less than 10 nm are uniformly spread on graphene nanosheets through pyrolysis of GO/ZIF-67. The relative mass ratio of graphene to Co3O4 is controlled by adjusting the repeated numbers of GO in precursor solutions. For application as anode material of Li-ion batteries, graphene/Co3O4 manifests good high rate behavior (877 mAh g−1 at the current density of 5000 mA g−1) and long-term cycling stability (714 mAh g−1 after 200 cycles).