Nanostructured vanadium oxide electrodes for enhanced lithium-ion intercalation

This article summarizes our most recent studies on improved Li(+)-intercalation properties in vanadium oxides by engineering the nanostructure and interlayer structure. The intercalation capacity and rate are enhanced by almost two orders of magnitude with appropriately fabricated nanostructures. Processing methods for single-crystal V(2)O(5) nanorod arrays, V(2)O(5)center dot nH(2)O nanotube arrays, and Ni/V(2)O(5)center dot nH(2)O core/shell nanocable arrays are presented; the morphologies, structures, and growth mechanisms of these nanostructures are discussed. Electrochemical analysis demonstrates that the intercalation properties of all three types of nanostructure exhibit significantly enhanced storage capacity and rate performance compared to the film electrode of vanadium pentoxide. Addition of TiO(2) orthorhombic V(2)O(5) is found to affect the crystallinity, microstructure, and possible interaction force between adjacent layers in V(2)O(5), and subsequently leads to enhanced Li(+)-intercalation properties in V(2)O(5). The amount of water intercalated in V(2)O(5) is found to have a significant influence on the interlayer spacing and electrochemical performance of V(2)O(5)center dot nH(2)O. A systematic electrochemical study has demonstrated that the V(2)O(5)center dot 0.3H(2)O film has the optimal water content and exhibits the best Li(+)-intercalation performance.