One-step solvothermal synthesis of hierarchical WO3 hollow microspheres with excellent NO gas sensing properties

Abstract In this work, the hierarchical WO3 hollow microspheres were synthesized through a facile one-step solvothermal method followed by the subsequent thermal treatment. The crystal structure, morphology and microstructure were characterized by various techniques. The sensors fabricated with this WO3 hollow microspheres exhibited ultrahigh response of 380 toward 5 ppm NO under 150 °C, and it also showed high selectivity, reliable repeatability and quick response/recovery characteristics. The excellent NO gas sensing properties is mainly owing to the hierarchical hollow microspheres structure with high specific surface area and effective gas diffusion ability.