Vertical, dense and uniform V_2O_5 nanoneedle arrays on carbon foam for boosting electrochemical performance

摘要

For the preparation of nanomaterials applied in supercapacitors, a rational and controllable strategy is generally developed to optimize the framework and augment the properties of them to a great extent. In this paper, we demonstrate a novel 1D@3D microstructure nanocomposite of V2O5@CF that is by means of suitably regulating the concentration of V2O5, and effectively developing its application in the supercapacitor. First, the carbon foam (CF) acts as the framework owning to its distinctive three-dimensional structure, which was obtained from the carbonization of melamine foam (MF). Then, one-dimensional V2O5 nanoneedles are implemented by a one-step hydrothermal method and propagated vertically and uniformly on the surface of CF. In virtue of suitable regulation on the concentration of V2O5, the prepared V2O5@CF composite exhibits desirable microstructure and performance. The specific capacity of this 1D@3D nanocomposite reaches 220.6 C/g at the current density of 1.0 A/g, which maintains 74.5% of initial capacities after 5000 incessant charge/discharge cycles, exposing excellent durability. Furthermore, the assembled asymmetric supercapacitor based on the V2O5@CF composite possesses outstanding specific energy of 28.1 Wh/kg and specific power of 3772.3 W/kg. The electrochemical performance of V2O5@CF nanocomposite is primely promoted by the rational and controllable strategy of preparation, which broadens the application of V2O5 and carbon foam in supercapacitor.