Enhanced gas sensing properties of Pt-loaded TeO 2 nanorods

Abstract

The NO 2 gas sensing properties of multiple-networked, Pt-loaded TeO 2 nanorod sensors were examined. Scanning electron microscopy revealed nanowires with diameters of 50-100 nm and lengths of a few micrometers. Transmission electron microscopy and X-ray diffraction showed that the nanrods were tetragonal-structured, single crystal TeO 2. The Pt-loaded TeO 2 nanorod sensors exhibited sensitivities of 11.00, 10.26, 11.23 and 11.97% at NO 2 concentrations of 10, 50, 100 and 200 ppm, respectively, at 300 °C. These sensitivities were more than 10 times higher than those of bare-TeO 2 nanorod sensors. The response times of the sensors were 310, 260, 270 and 230 sec at NO 2 concentrations of 10, 50, 100 and 200 ppm, respectively. The recovery times of the Pt-loaded TeO 2 nanorods were 390, 330, 335, and 330 sec at NO 2 concentrations of 10, 50, 100 and 200 ppm, respectively. The origin of the enhanced sensing properties of the TeO 2 nanorods by Pt loading is discussed.