▎ 摘　　要

Na0.33V2O5 nanosheet@graphene composites were explored as cathodes for sodium ion batteries for the first time. Here, Na0.33V2O5 nanosheet@graphene composites with special sandwich-like nanostructures were synthesized. The composites exhibit high discharge capacity (of ca. 213 mA h g(-1) at 20 mA g(-1)), good cycling stability (with a capacity retention of 83.3% at 50 mA g(-1) after 100 cycles) and desirable rate performance (88.2 mA h g(-1) at an extremely high current density of 6000 mA g(-1)) as cathodes for sodium storage. Notably, the as-synthesized Na0.33V2O5 nanosheet@graphene composites show much higher specific capacity and better rate capability than those reported Na0.33V2O5 materials which were usually tested at relatively low currents (no more than 200 mA g(-1)) and showed low capacities (less than 150 mA h g(-1)). (C) 2016 Elsevier B.V. All rights reserved.