Abstract
Highly ordered mixed V2O5-TiO2 nanotubes can be formed by self-organizing anodization of Ti-V alloys with vanadium content of up to 18 at%. In the resulting oxide nanotube arrays, the vanadium is electrochemically switchable leading to a specific capacitance that can reach up to 220 F g(-1) and an energy density of 19.56 Wh kg(-1) with perfect reversibility and long-term stability. Thus these mixed oxide nanotubes may be considered as a promising candidate for supercapacitors.