Integration of network-like porous NiMoO4 nanoarchitectures assembled with ultrathin mesoporous nanosheets on three-dimensional graphene foam for highly reversible lithium storage

Abstract

Interconnected ultrathin mesoporous nickel molybdate (NiMoO₄) nanosheets with a network-like porous structure supported on a three-dimensional (3D) macroporous graphene network were successfully synthesized by a facile chemical vapor deposition (CVD) method and subsequent hydrothermal route. The building block NiMoO₄ nanosheets are curved with a thickness as small as 3–5 nm, and randomly connected with the adjacent nanosheets to self-assemble into continuous, interconnected and porous architectures. The NiMoO₄ nanosheets supported on the 3D graphene network could be directly evaluated as binder-free, integrated anodes for lithium-ion batteries (LIBs). Such unique 3D integrated architectures exhibited remarkable electrochemical performance with a high reversible capacity of 1155.54 mA h g⁻¹ at a current density of 200 mA g⁻¹, and an excellent cycling ability (89% of the initial reversible capacity remained after 120 cycles). The superior electrochemical performances could be attributed to the open network structure constituted of interconnected ultrathin mesoporous NiMoO₄ nanosheets directly grown on current collectors that could improve electron transport and enhance electrolyte diffusion efficiency.