Synthesis of bundled tungsten oxide nanowires with controllable morphology

Bundled tungsten oxide nanowires with controllable morphology were synthesized by a simple solvothermal method with tungsten hexachloride (WCl6) as precursor and cyclohexanol as solvent. The as-synthesized products were systematically characterized by using scanning electron microscopy, X-ray diffraction and transition electron microscopy. Brunauer–Emmett–Teller gas-sorption measurements were also employed. Accompanied by an apparent drop of specific surface area from 151 m2 g− 1 for the longer nanowires synthesized using a lower concentration of WCl6 to 106 m2 g− 1 for the shorter nanowires synthesized using a higher concentration of WCl6, a dramatically morphological evolution was also observed. With increasing concentration of tungsten hexachloride (WCl6) in cyclohexanol, the nanostructured bundles became larger, shorter and straighter, and finally a block-shape product occurred.