Thermochromic VO2 nanorods were prepared via thermal conversion of the metastable VO2-B phase synthesized by hydrothermal methods. We observe an increased thermochromic transition temperature to similar to 75-80 degrees C by variable-temperature infrared spectroscopy. Nano- and sub-micron structures of other vanadium oxides (V3O7, (NH4)(0.5)V2O5, and V2O5) were obtained simply by varying the starting materials in the hydrothermal synthesis. We also obtained nanostructures of the high temperature tetragonal rutile phase of VO2 by thermolysis of single-source vanadium (IV) precursors. (C) 2006 Elsevier Ltd. All rights reserved.