Synthesis of Nitrogen and Phosphorus Dual-Doped Graphene Oxide as High-Performance Anode Material for Lithium-Ion Batteries.

Nitrogen and phosphorus dual-doped graphene oxide was prepared by directly calcining a mixture of pure graphene oxide, urea (nitrogen source), and 1,2-bis(diphenylphosphino)methane (phosphorous source). The morphology and composition of the obtained dual-doped graphene oxide were confirmed by SEM, TEM, XRD pattern, Raman spectrum, and XPS. The nitrogen and phosphorous dual-doped graphene oxide was tested as an anode material of lithium-ion batteries (LIBs). The cycle and rate performance of the dual-doped graphene oxide were also examined. The dualdoped graphene oxide exhibited a superior initial discharge capacity of 2796 mAh·g-1 and excellent reversible capacity of 1200 mAh·g-1 at a current density of 100 mA·g-1 after 200 charge/discharge cycles, suggesting that the dual-doping of nitrogen and phosphorous is an effective way to enhance lithium-ion storage for graphene oxide.