A General Room Temperature Synthesis of Self-Assembled Urchin-like Nanostructured Vanadates for Lithium-Ion Batteries

Vanadium based materials are widely investigated as high-performance cathode materials for Lithium-ion batteries due to their high specific capacities, good reversibility and abundant resources in the earth's crust. Unlike commonly reported solvothermal synthesis of nanostructured materials at high temperature, herein, a novel general room temperature approach is presented for the synthesis of different vanadium based precursors with nanorods self-assembled urchin-like hierarchial structure, which can be readily transformed into several vanadates, including Na 0.33 V 2 O 5 , Ag 0.33 V 2 O 5 , Ag 1.2 V 2 O 5 and LiV 3 O 8 , when calcined in air. The as-prepared vanadates materials well retained the unique urchin-like hierarchial nanostructure and showed good cycling performance and rate capability as cathode materials for Lithium ion batteries. Specifically, the as-synthesized Na 0.33 V 2 O 5 cathode materials delivered a high specific capacity of 278 mAh/g when cycled at a current density of 100 mA/g. Compared with commonly used solvothermal synthesis at elevated temperature, this presented approach is more economic and more energy saving, as the nanostructure can be obtained at room temperature. In addition, this approach can be easily generalized to synthesize all kinds of other vanadates such as copper vanadates, cobalt vanadates, and potassium vanadates.