Improved acetone gas sensing performance based on optimization of a transition metal doped WO ₃ system at room temperature

Abstract

Abstract This paper proposes an effective strategy of material system optimization to improve acetone gas sensing performance based on hydrothermally processed transition metal (Fe, Co or Ni)-doped WO 3 materials. A detailed comparison of the capability of pure WO 3 and X:WO 3 (X = Fe, Co, Ni) to sense acetone gas at room temperature was performed. It was found that the sensitivity of Ni:WO 3 nanoflowers to acetone was much higher than that of pure WO 3 , Fe:WO 3 and Co:WO 3 under white light irradiation. To obtain a highly sensitive acetone gas sensor, the molar doping ratio of Ni to WO 3 was further optimized. It was found that 3%Ni:WO 3 had the highest response–recovery speed and the best target gas selectivity. Acetone with a concentration as low as 2 ppm can be detected at room temperature (20 °C). The sensitivity enhancement mechanism of the Ni:WO 3 gas sensor is also discussed. It is expected that under white light irradiation the proposed Ni-doped WO 3 can be used as a highly sensitive and selective acetone gas sensor at room temperature.