A facile route to tungsten oxide nanomaterials with controlled morphology and structure

Various tungsten oxide-based nanomaterials have been prepared by a modified plasma arc gas condensation technique without the use of catalysts or substrates. These products could be obtained by controlling the processing parameters during experiment. All the as-obtained samples were characterized by field emission gun scanning electron microscopy, high-resolution transmission electron microscopy, and X-ray diffraction techniques. The results revealed that as-prepared tungsten oxide nanomaterials (WO₃, W₁₉O ₅₅ and W₅O₁₄) with different phases and morphologies could be obtained by decreasing the oxygen content in the chamber. In addition, W₁₈O₄₉ nanotubes and nanorod bundles were fabricated by controlling the Ar/O₂ ratio under He plasma gas. W ₁₈O₄₉/TiO₂ core-shell nanoparticles were also prepared by evaporating a dual target. The experimental results showed that the present technique is unique and feasible for the fabrication of nanomaterials for use in different applications.