Self-heated hydrogen gas sensors based on Pt-coated W18O49 nanowire networks with high sensitivity, good selectivity and low power consumption

Self-heating effect can be applied to develop gas sensors avoiding use of external heaters. We report here a prototype self-heated hydrogen gas sensor based on Pt-coated W18O49 nanowire networks. Such a sensor has been shown to have promising performance, e.g., high sensitivity (able to detect down to 50 ppm of H-2), good selectivity (poor response to ethanol, CH4, CO, and C3H8), and low power consumption of 30-60 mW at 6 V compatible to a portable device. Coaxial cable model and percolation theory are applied to explain the gas sensing effect of the Pt-coated W18O49 nanowire networks. (C) 2010 Elsevier B.V. All rights reserved.