Vertically aligned mixed V 2O 5-TiO 2 nanotube arrays for supercapacitor applications

Department of Materials Science, WW4-LKO, University of Erlangen-Nuremberg, Martensstrasse 7, 91058 Erlangen, Germany.
Chemical Communications (Impact Factor: 6.72). 07/2011; 47(27). DOI: 10.1039/c1cc11811k

ABSTRACT Highly ordered mixed V 2O 5-TiO 2 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. © 2011 The Royal Society of Chemistry.

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