Self-assembling vanadium oxide nanotubes by organic molecular templates

Vanadium oxide nanotubes were synthesized as the main product by hydrothermal self-assembling from ammonium metavanadate (NH4VO3) and organic molecules as structure-directing templates. Several kinds of templates including primary amines ((CH2n+1NH2)-H-n), alpha,omega-diamines (H2N[CH2](n)NH2), and quaternary ammonium salt (CTAB) were demonstrated to be appropriate for the formation of nanotubes. The morphologies and structures of the nanotubes were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), and thermal gravimetric analysis (TGA). The nanotubes were found forming together with the layered structures and the sheetlike structures. On the basis of the growth mechanism of WS2 nanotubes proposed by our group, a possible rolling mechanism was proposed, which might be a suitable general formation mechanism for types of nanotubes from lamellar structures.