“…Up to now, several methods have been reported for the synthesis of one-dimensional (1D) WO 3 nanostructures, including chemical vapour deposition (CVD) [15], flame synthesis [16], thermal evaporation [17], hydrothermal reaction [18,19], electro spinning [20], spray pyrolysis [21], microemulsion based solution synthesis [22] and electron-beam annealing [23]. Hydrothermal treatment can provide a cost-effective and morphology controllable route to obtain 1-D nanostructures, and hence has become an advantageous method.…”