Self-assembled 3D NixCo3-xO4 pseudocube superstructure as potential anode material for Li-Ion batteries

Abstract Self-assembled 3D NixCo3-xO4 pseudocube superstructure was successfully synthesized through a facile solvothermal strategy followed by a calcination process. Structure analyses shows that the mesoscopic 3D pseudocube superstructures are stacked by mesoporous nanoflakes with tiny nanoparticles as basic unit, as an anode material for Li-Ion Batteries, such a hierarchical structure can greatly buffer the volume expansion and effectively shorten lithium ion diffusion distance. Comparing with the 1D NiCo2O4 nanorods and 2D Co3O4 nanoflakes synthesized via changing the synthesis parameters, it conclude that the nickel leach process plays a key role in formation of this unique morphology and a mechanism is proposed. As expected, the 3D NixCo3-xO4 pseudocube exhibits the most impressive lithium storage performance, delivering a high reversible capacity of 1225 mA h g−1 after 200 cycles at 200 mA g−1, and even at high current of 4000 mA g−1, it still delivers a specific capacity of 645 mA h g−1. These results suggest a promising application for advanced energy storage units.