Template-free synthesis of V2O5 hierarchical nanosheet-assembled microspheres with excellent cycling stability

V2O5 microspheres with hierarchical structure via a facile two-step strategy. The first is preparing vanadium glycolate precursor through polyol medium template-free process and the second is subsequent thermal annealing treatment of the well-prepared precursors at high temperature in air. However, just by one-plot calcination of vanadium(IV) acetylacetone, V2O5 nanorods were obtained. The gained metal oxide were characterized by different physical and electrochemical analytical techniques. Electrochemical testing results show that V2O5 microspheres displayed a high specific discharge capacity of 275 mAh g−1 at 1 C which is higher than the obtained nanorods, and the microspheres still kept 243 mAh g−1 after 200 cycles. Notably, the nanosheet-assembled microspheres as electrode materials still show 200 mAh g−1 even at a rate of 5 C after 500 cycles. These results demonstrated that the well-prepared nanosheet-assembled microspheres are a fine cathode material for lithium ion battery with a high specific capacity and excellent cycle stability.