Ru-decorated WO3 nanosheets for efficient xylene gas sensing application

Abstract In this work, WO3 nanosheets are synthesized successfully through the hydrothermal method. Ru is thereafter efficiently loaded on the surface of WO3 using the ethylene glycol-assisted solvothermal method. The gas sensing test shows that 0.5 wt% Ru-WO3 exhibits the best performance towards xylene detection. Compared with the pure WO3 sensor, the gas response of the sensor based on 0.5 wt% Ru-WO3 in 100 ppm xylene increases from 11 to 73, and the operating temperature decreases from 375 °C to 280 °C. And an ultra-low detection limit of 25 ppb is obtained. In addition, the gas sensing performance of the Ru-loaded WO3 sensor is much better than that of Au, Pt and Pd-loaded WO3 sensors. The enhanced gas sensing performance can be attributed to the catalytic overflow of Ru and the formation of heterojunction between RuO2 and WO3. It is expected that this finding gives rise to further efforts on efficient and low-cost xylene sensors that are based on Ru-loaded WO3.