Synthesis of hemispherical WO3/graphene nanocomposite by a microwave-assisted hydrothermal method and the gas-sensing properties to triethylamine

•Hemispherical WO3/graphene was synthesized by the microwave-assisted hydrothermal method.•Sensors exhibit improved sensing performance to amine gases at room temperature.•Sensitivity of WO3/graphene to triethylamine can reach 205 at room temperature.

WO3 nanoparticle and hemispherical WO3/graphene nanocomposite were successfully synthesized via a microwave-assisted hydrothermal method. The obtained samples were characterized by X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscope (SEM) techniques. The gas-sensing performance of the as-synthesized materials was also investigated. The experimental results revealed that the graphene plays a very important role in the crystal structure evolution process from WO3 nanoparticle to hemispherical WO3/graphene nanocomposite. The hemispherical WO3/graphene nanocomposite with hollow structure shows far better gas-sensing performance for amine gases at room temperature, especially for triethylamine.