Rational Design of WO Nanostructures as the Anode Materials for Lithium-Ion Batteries with Enhanced Electrochemical Performance.

A facile, one-step hydrothermal method was employed to synthesize two kinds of WO nanostructures. By using different kinds of sylvine, tungsten trioxide (WO) with different morphologies of microflowers and nanowires was obtained, respectively. The discharge capacities for microflowers and nanowires are 107 and 146 mAh g after 180 cycles, and their corresponding capacity retentions after the first cycle are 72 and 85 %, respectively. Even at a high current density of 1,600 mAh g, the discharge capacities of WO microflowers and nanowires are as high as 433 and 557 mAh g after 40 cycles, in which the current densities were increased stepwise. It is worth mentioned that the rate capability of the nanowires is superior to that of the microflowers. However, the cycle performance of the microflowers is better than nanowires, revealing that the morphology and structure of the as-synthesized WO products can exert great influence on the electrochemical performances.