From V2O5 foam to VO2(B) nanoneedles

Nanoneedles B phase VO2 with high crystallinity was hydrothermally synthesized from the foam prepared by mixing V2O5, aniline and H2O in the mol ratio 1:1:258. The samples have been characterized by scanning electron microscopy, transmission electron microscopy, X-ray powder diffraction and thermal analysis. Regularly sized VO2(B) nanoneedles have the following dimensions: 0.5–5 μm in length and about 50 nm in average diameter. According to transmission electron microscopy investigations, the V2O5 crystals resulting from the foam exhibit nanoparticles sizes between 50 and 100 nm. This way of synthesis provides a new simple and elegant route to elaborate the vanadium dioxide VO2(B) nanoneedles and V2O5 nanoparticles under soft conditions.