Vanadium oxide nanotubes were obtained as the main product in a sol-gel reaction followed by hydrothermal treatment from V2O5 precursors and octadecylamine. The tubes consist of concentric shells of highly crystalline vanadium oxide separated by alternation organic amine layers. The vanadium oxide nanotubes are redox-active and can electrochemically insert magnesium reversibly. The electrochemical insertion magnesium properties of vanadium oxide nanotubes were studied by electrochemical impedance (EIS) and cyclic voltammogram. (c) 2005 Elsevier B.V. All rights reserved.