Article

Controlling the Formation of Rodlike V2O5 Nanocrystals on Reduced Graphene Oxide for High-Performance Supercapacitors

ACS Applied Materials & Interfaces (Impact Factor: 6.72). 10/2013; 5(21). DOI: 10.1021/am403739g
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ABSTRACT Vanadium pentoxide (V2O5) has attracted much attention for energy storage application due to its high faradaic activity and stable crystal structures, which make it promising electrode materials for supercapacitors. However, the low electronic conductivity and small lithium ion diffusion coefficient of V2O5 limit its practical applications. To overcome these limitations, a facile and efficient method is here demonstrated for the fabrication of V2O5/reduced graphene oxide (rGO) nanocomposites as electrode materials for supercapacitors. With this method, the reduction of graphene oxide can be achieved in a cost-effective and envi-ronmentally friendly solvent, without the addition of any other toxic reducing agent. Importantly, this solvent can control the forma-tion of the uniform rod-like V2O5 nanocrystals on the surface of rGO. Compared to pure V2O5 microspheres, the V2O5/rGO nano-composite materials exhibited higher specific capacitance of 537 F g-1 at a current density of 1 A g-1 in neutral aqueous electrolytes, higher energy density of 74.58 Wh Kg-1 at a power density of 500 W kg-1 and better stability even after 1000 charge/discharge cy-cles. Their excellent performances can be attributed to the synergistic effect of rGO and rod-like V2O5 nanocrystals. Such impres-sive results may promote new opportunities for these electrode materials in high energy density storage systems.

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