GO-graphene ink-derived hierarchical 3D-graphene architecture supported Fe3O4 nanodots as high-performance electrodes for lithium/sodium storage and supercapacitors.

Transition metal oxides/carbon materials are of great interest for promising highly efficient energy storage applications owing to their low cost and eco-friendlines. Nevertheless, creating an electrode material with enhanced conductivity and electrochemical activity remains a great challenge. Here a design and fabrication of Fe3O4 nanodots (∼5.2 nm) loading onto the hierarchical three dimensional graphene (Fe3O4/3D-graphene) via an interesting strategy is reported. The key factor in developing the unique 3D-graphene architecture assemblies with a graphene oxide-graphene composite ink and modifying sol-gel chemistry method is a promising strategy. The 3D-graphene with 3D omnibearing conductive and interconnecting pores can facilitate the penetration of electrolyte, accommodate the volume change and inhibit the aggregation of Fe3O4 nanodots upon cycling. Benefiting from the advantages of the positive synergistic effects of Fe3O4 nanodots and multilevel structures of graphene, the Fe3O4/3D-graphene electrode exhibits excellent electrochemical performances for Li/Na-ion batteries and electrochemical capacitors. As a result of the enhanced electrochemical performance, Fe3O4/3D-graphene hybrids could be regarded as a promising electrode for Li/Na-ion battery and supercapacitor.