Ethanol gas sensing performance of Zn2SnO4 nanopowder prepared via a hydrothermal route with different solution pH values

The nanopowders of Zn2SnO4 were prepared via a hydrothermal method with different solution pH values. The influence of the pH value on the crystal structure, morphology, specific surface area, and gas sensing performance was comparatively investigated. The sensor prepared at the pH value of 13 showed the most promising integral ethanol gas sensing properties. At the optimal operating temperature of 300 degrees C, the sensor response increased linearly with ethanol concentration among the range of 5-200 ppm and showed a sensitivity of 0.213/ppm, a response/recovery time less than 15 s, and a high ethanol gas sensing selectivity against to acetone, methylbenzene and methanol. The related sensing mechanism was discussed based on the structural characteristics and the sensing properties. The results indicated that as-prepared Zn2SnO4 nanopowders might be a promising candidate material for fabricating practical ethanol gas sensors. (C) 2015 Elsevier B.V. All rights reserved.