Enhanced sensing performance of TiO2/Ag2V4O11 nanoheterostructures to ethanol gas

High performance sensor for gas species detection is a significant task not only for fundamental sciences but also for industries. In this study, a new type of ethanol gas sensor based on one-dimensional TiO2/Ag2V4O11 nanoheterostructures (NHSs) is reported. The sensitivity of the NHSs to ethanol is much higher than those of pure TiO2 and Ag2V4O11. By regulating the content of TiO2 and Ag2V4O11, it is found that TiO2/Ag2V4O11 NHSs with T/A (TiO2/Ag2V4O11) molar ratio of 2:1 exhibit excellent sensing performances to ethanol. The sensitivity at 300 °C to 100 ppm ethanol is 25.6, about 6 times and 3 times higher than TiO2 and Ag2V4O11, respectively, and the sensor also possesses good selectivity to ethanol gas. Specifically, the NHSs exhibit efficient sensitivity (4.2–100 ppm ethanol gas) and excellent stability at room temperature. High-depth mechanism study reveals that besides the contribution of the fast electron transfer properties of the Ag2V4O11, the formation of nanoheterojunctions and the rich surface interfaces rooting from the hybridization of nanoparticles (NPs) and nanowires (NWs) can significantly enhance the sensing performance of the NHSs.