Highly sensitive acetone sensors based on flame-spray-made La<inf>2</inf>O<inf>3</inf>-doped SnO<inf>2</inf>nanoparticulate thick films

Abstract

© 2018 Elsevier B.V. In the present work, flame-spray-made La2O3-doped SnO2nanoparticles with 0.1−2 wt% La contents were systematically studied for acetone detection. The particle and sensing film properties were characterized by X-ray diffraction, nitrogen adsorption, electron microscopy, energy dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy. The sensing films were tested towards 0.1–400 ppm acetone at operating temperatures ranging from 150 to 400 °C in dry air. Gas-sensing results demonstrated that the SnO2sensing film with the optimal La content of 0.5 wt% exhibited a very high response of 3626 toward 400 ppm acetone with a short response time of 2.8 s at the optimal operating temperature of 350 °C. Moreover, the sensors displayed high acetone selectivity against SO2, H2S, NO2, C6H6, C7H8, C8H10and CH2O. Therefore, the La2O3-doped SnO2sensors are promising for sensitive and selective detections of acetone at low concentrations.