Novel Sponge-like Structure of a High-Capacity Nitrogen–Fluorine Codoped Reduced Graphene (N, F-rGO) Film Electrode and Electrochemical Performance in Lithium-Ion Batteries

Abstract

The nitrogen–fluorine-codoped reduced GO film (N, F-rGO film) is prepared by a simple one-step pyrolysis process. The as-prepared N, F-rGO film displays a loose porous structure between layers, and the N- and F-doping contents of the resulting N, F-rGO film were 4 and 1.3%, respectively. As a negative electrode for lithium-ion batteries (LIBs), the as-prepared N, F-rGO film exhibits high reversible capacity and good cycle stability. It delivers an initial discharge capacity of 2133 mA h g–1 and a high reversible specific discharge capacity of 878 mA h g–1 at the current density of 200 mA g–1. Even at the current density of 2 A g–1, the reversible specific capacity could be 344 mA h g–1 after 500 cycles. The N, F-double doping and the high-surface area mesoporous structure of rGO provide efficient ionic diffusion path, offering sufficient active sites for lithium-ion storage, resulting in excellent electrochemical performance.