Pseudocapacitive properties of electrochemically prepared vanadium oxide on carbon nanotube film substrate

Vanadium oxide (V2O5 center dot xH(2)O) was electrodeposited on a carbon nanotube (CNT) film substrate with a three-dimensional porous structure at the nanometer scale as an electrode material for pseudocapacitors using organic electrolytes. Microstructures of the electrochemically prepared V2O5 center dot xH(2)O on the CNT film substrate (V2O5 center dot xH(2)O/CNT film electrode) showed that V2O5 center dot xH(2)O was heterogeneously nucleated and uniformly deposited on the CNT film substrate. The V2O5 center dot xH(2)O/CNT film electrode showed not only a high specific Li-ion capacitance of 1230 F/g with respect to the mass of the V2O5 center dot xH(2)O, but also a high rate capability. The maximum specific energy of 851 Wh/kg and specific power of 125 kW/kg were obtained from the discharging curves of the V2O5 center dot xH(2)O/CNT film electrode. They could be attributed to the electrode construction comprising a very thin film of V2O5 center dot xH(2)O deposited on the conductive CNT film substrate with a three-dimensional nanoporous structure. (c) 2006 The Electrochemical Society.