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 V2O5 nanorod arrays, V2O5·n H2O nanotube arrays, and Ni/V2O5·n H2O 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 TiO2 to orthorhombic V2O5 is found to affect the crystallinity, microstructure, and possible interaction force between adjacent layers in V2O5, and subsequently leads to enhanced Li+‐intercalation properties in V2O5. The amount of water intercalated in V2O5 is found to have a significant influence on the interlayer spacing and electrochemical performance of V2O5·n H2O. A systematic electrochemical study has demonstrated that the V2O5·0.3 H2O film has the optimal water content and exhibits the best Li+‐intercalation performance.

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This paper reports a study on template-growth and electrochemical properties of single-crystal vanadium pentoxide (V 2 O 5 ) nanorod arrays from VOSO 4 aqueous solution using electrochemical deposition. Uniformly sized vanadium oxide nanorods with a length of about 10 µm with diameters ranging from 100 to 200 nm were grown over a large area with near unidirectional alignment. These nanorods have single-crystalline structure with a growth direction of [010]. Electrochemical property analysis indicates that nanorod array electrodes have significantly higher current density and energy storage density than sol-gel-derived V 2 O 5 films.

Nanotube arrays of amorphous vanadium pentoxide (V(2)O(5)) were synthesized via template-based electrodeposition, and its electrochemical properties were investigated for Li-ion intercalation applications. The nanotubes have a length of 10 microm, outer diameter of 200 nm and inner diameter of 100 nm. Electrochemical analyses demonstrate that the V(2)O(5) nanotube array delivers a high initial capacity of 300 mAh/g, about twice that of the electrochemically prepared V(2)O(5) film. Although the V(2)O(5) nanotube array shows a more drastic degradation than the film under electrochemical redox cycles, the nanotube array reaches a stabilized capacity of 160 mAh/g, which remains about 1.3 times the stabilized capacity of the film.

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