One step synthesis of vesicular Na3V2(PO4)2F3 and network of Na3V2(PO4)2F3@graphene nanosheets with improved electrochemical performance as cathode material for sodium ion battery

Abstract

Here, we report a novel structure of vesicular Na3V2(PO4)2F3 (NVPF) and a highly connected network of NVPF@graphene nanosheets (GN) via a one-step hydrothermal method, which is reported for the first time. As cathode material for Sodium ion battery (SIB), NVPF@16%GN shows a high average discharge plateau at 3.8 V with reversible capacity of 111.1 and 67.4 mAh g−1 at 0.2C and 5C rate, respectively. The obviously improved electrochemical performance should be contributed to the formation of superior conductive network of vesicular NVPF active material combing with GN, supplying adequate and shortened passageway for electronic transport and sodium ion diffusion.