Au-nanoparticle-decorated SnO2 nanorod sensor with enhanced xylene-sensing performance

In this work, pure and Au-nanoparticle-decorated SnO 2 nanorods were prepared via a one-step hydrothermal method combined with a facile deposition process, and then characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, high-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy. The xylene-sensing performance of the nanorods was also investigated. The results show that Au nanoparticles with an average diameter of 4-6 nm were immobilized on the surface of rutile SnO 2 nanorods. As the amount of Au increased, the surface-adsorbed oxygen species gradually increased. The 12 mol% Au-SnO 2 nanorods exhibited the highest response to 50 ppm xylene, a lower operating temperature (279 to 255°C), favorable selectivity, and fast response-recovery speed (3 and 4 seconds, respectively). These properties made the fabricated nanorods good candidates for xylene detection. The possible mechanism for the enhanced xylene-sensing performance is discussed.