Complexing surfactants-mediated hydrothermal synthesis of WO3 microspheres for gas sensing applications

WO3 microspheres with hierarchical architectures were synthesized by a facile hydrothermal method in the presence of K2SO4 and H2C2O4 with a molar ratio of 1:1, accompanied by WO3 products mediated by only K2SO4 or H2C2O4. The effect of surfactants on product morphology was investigated by means of XRD, SEM, XPS and BET measurements. Structural characterizations demonstrate that WO3 microspheres mediated by complexing surfactants are assembled by numerous one-dimensional hexagonal nanorods with single crystal. Based on the comparative studies, WO3 microspheres mediated by complexing surfactants show the highest effective surface area and optimal morphology distribution, leading to an excellent NO2 gas sensing properties.