Porous graphene to encapsulate Na6.24Fe4.88(P2O7)4 as composite cathode materials for Na-ion batteries

Na6.24Fe4.88(P2O7)(4)@porous graphene composite is fabricated as a cathode of Na-ion batteries for the first time by a hydrothermally assisted sol-gel process. In comparison to non-porous and pristine composites, the as-prepared material exhibits much higher capacity and better rate performance, which are mainly attributed to the high conductivity and rational porous structure of graphene with a significantly increased diffusion coefficient.