Synthesis, formation mechanism and sensing properties of WO3 hydrate nanowire netted-spheres

Tungsten oxide hydrate nanowire netted-spheres were successfully synthesized in the glycol solution using a facile solvothermal approach. The nanowires with uniform diameter of 4–6 nm are actually a kind of tungsten oxide hydrate/surfactant hybrid materials. The influence of surfactant, solvent, time and temperature on tailoring morphology was investigated in detail. The possible formation process of WO3 hydrate nanowire netted-sphere was proposed. Sensing properties of such WO3 hydrate sensor show that the desirable sensing characteristics towards 100 ppm ammonia gas at 320 °C were obtained, such as rapid response (18.3 s), high sensitivity, good reproducibility and stability.