Synthesis and characterization of V3O7⋅⋅H2O nanobelts

V 3O7⋅H2O nanobelts were prepared by a hydrothermal method at 190 ∘C using V 2O5⋅nH2O gel and H2C2O4⋅2H2O as starting agents. The nanobelts obtained have diameters ranging from 40 to 70 nm with lengths of up to several micrometers. Their morphology and structure have been characterized by XRD, SEM, TEM and IR spectroscopy. The effect of the annealing temperature on the morphology of the resulting product has been investigated. XRD and SEM showed that thermal annealing of the V 3O7⋅H2O sample in air led to the collapse of the V 3O7⋅H2O nanobelt structure and the convert into V 2O5 nanobelts. For the first time V 2O5 nanobelts with an ultrahigh aspect-ratio have been obtained in air. Furthermore, electrical conductivity and static magnetic susceptibility measurements have been carried out.