Monodispersed nickel phosphide nanocrystals in situ grown on reduced graphene oxide matrix with excellent performance as the anode for lithium-ion batteries

By using cheap, stable, relative low-toxic precursors (the key of the design), a nanocomposite anode material composed of monodispersed nickel phosphide (Ni 2 P) nanocrystals in situ grown into three dimensional reduced graphene oxide (RGO) matrix has been fabricated through a “heating-up” synthesis method. With an average size of 5 nm, the Ni 2 P nanocrystals are wrapped within the interior as well as on the surface of the curling RGO matrix without aggregation. In this nanostructure , RGO has excellent conductivity and an interconnected porous network, enabling the Ni 2 P/RGO nanocomposites to provide ways for rapid electron transfer and lithium ion transport. Meanwhile, due to the small size and monodispersed phase of the Ni 2 P nanocrystals, it can adapt to the volume change during charging/discharging processes. As a result, the excellent lithium-storage performance has been shown by Ni 2 P/RGO nanocomposites, concerning a long-life cycling stability (389.9 mAh g −1 after 1000 cycles at 1 C) and a high rate capability (197.7 mAh g −1 at 50 C).