A high-capacity NiCo2O4@reduced graphene oxide nanocomposite Li-ion battery anode

Highlights: • A special sandwich-nanostructured NiCo₂O₄@rGO composites were developed. • It involves accessible dipping and hydrothermal process followed by heat treatment. • The sandwiched NiCo₂O₄@rGO anodes exhibit high stable capacity and rate performance. • High performance is ascribed to the special sandwiched NiCo₂O₄@rGO nanocomposites. Nano-engineering graphene-based composite anodes have motivated broad investigations of the high energy density lithium-ion batteries. Here, a sandwich-like and porous NiCo₂O₄@reduced graphene oxide (rGO) nanocomposite was presented. Through an incipient dipping process, the NiCo₂O₄ precursors attach on the rGO densely, which significantly improves the material loading of the NiCo₂O₄@rGO composites. Serving as an anode of the lithium-ion battery, the NiCo₂O₄@rGO composites exhibit an unprecedented capacity of 1566 mAh g⁻¹ cycling at a current density of 1000 mA g⁻¹ over 700 times; while a capacity of 886 mAh g⁻¹ at 100 mA g⁻¹ over 100 cycles was achieved upon a NiCo₂O₄@rGO//LiCoO₂ full-cell, which indicates a promising potential for high energy density battery applications.