Preparation of VO2 nanowires and their electric characterization

Large-scale VO2 nanowires have been synthesized by two-step method. First, we have been obtained (NH4)0.5V2O5 nanowire precursors by hydrothermal treatment of ammonium metavanadate solution at 170 deg. C. Secondly, the precursors have been sealed in quartz tube in vacuum and annealed to form VO2 nanowires at 570 deg. C. Scanning electron microscope and transmission electron microscope analysis show that the nanowires have self-assembling nanostructure with the diameter of about 80-200 nm, length up to125 μm. Electrical transport measurements show that it is semiconductor with conduction activate energy of 0.128 eV. A metal-semiconductor transition can be observed around 341 K