Hydrothermal synthesis of hierarchical WO3/NiO porous microsphere with enhanced gas sensing performances

Two novel hierarchical WO3/NiO microspheres with porous and rough surface have been prepared through a simple one-stop hydrothermal method. Interestingly, it is a surprise that the introduction of different amounts of WO3 plays a critical role in the growth and self-assembly of nanosheets and then the morphology of microsphere. Further gas sensing experiment demonstrates that the sensor based on porous microsphere possesses prominent performance towards 100 ppm ethanol at the optimal working temperature of 300 degrees C compared with that of rough microsphere. It is believed that the enhanced gas sensing properties benefit from the porous structure on the surface with abundant active sites and gas passages for sufficient gas adsorption and diffusion. (C) 2020 Elsevier B.V. All rights reserved.