Synthesis of interconnected mesoporous ZnCoO nanosheets on a 3D graphene foam as a binder-free anode for high-performance Li-ion batteries.

Interconnected mesoporous sheet-like ZnCoO nanomaterials directly grown on a three-dimensional (3D) graphene film (GF) coated on Ni foam (NF) have been successfully synthesized an effective chemical vapor deposition (CVD) method combined with a subsequent hydrothermal route. When the ZnCoO@3DGF@NF composite material with a high surface area of 46.06 m g is evaluated as a binder-free anode material for lithium ion batteries, it exhibits a superior electrochemical performance with a high discharge capacity (1223 mA h g at a current density of 500 mA g after 240 cycles), and an excellent reversibility (coulombic efficiency of 97-99%). Such an outstanding electrochemical performance may be attributed to its unique mesoporous sheet-like nanostructure with a 3DGF supporting, which can facilitate the electrolyte penetration and accelerate the ion/electron transport, as well as buffer the volume variation during charge/discharge processes.