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

Pictured above is the transient response of the sensor to different ethanol concentrations measured at 300°C. Among the three sensors, the one based on the Zn2SnO4 nanopowder prepared with the solution pH value of 13 exhibits the best integral ethanol sensing performances. •Zn2SnO4 nanopowder was prepared via a hydrothermal method.•The influence of the pH value on the gas sensing performance was investigated.•The sensor prepared at pH of 13 showed the most promising gas sensing properties. 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°C, the sensor response increased linearly with ethanol concentration among the range of 5–200ppm and showed a sensitivity of 0.213/ppm, a response/recovery time less than 15s, 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.