Bimetal PdAu decorated SnO2 nanosheets based gas sensor with temperature-dependent dual selectivity for detecting formaldehyde and acetone

A highly sensitive gas sensor employing biomorphic SnO2with multi-level tubes/pores structure: bio-templated from waste of flax

“…, O À ). 6,33,34 The response then decreased rapidly with further increase of the operating temperature, which may occur because large amounts of reactants were desorbed. 6,33 Therefore, 130 C is the optimal operating temperature of the MLTPS sensor; this optimal operating temperature is obviously lower than those in numerous reported studies (higher operating temperatures from 200 C to 600 C).…”

“…6,33,34 The response then decreased rapidly with further increase of the operating temperature, which may occur because large amounts of reactants were desorbed. 6,33 Therefore, 130 C is the optimal operating temperature of the MLTPS sensor; this optimal operating temperature is obviously lower than those in numerous reported studies (higher operating temperatures from 200 C to 600 C). 22,[25][26][27] Here, the low operating temperature (130 C) is due to the fact that MLTPS has abundant active sites, a large surface-to-volume ratio and numerous gas diffusion channels, which results in a faster adsorption/desorption rate.…”

“…Hence, selectivity is of great importance to practical applications, such as indoor toxic gas detection and biomarkers. 6 Here, in order to clarify its potential gas sensing applications for indoor toxic gas detection and biomarkers, the selectivity of the MLTPS gas sensor was tested with 50 ppm potential interference gases (ammonia (NH 3 ), methanol (CH 3 OH), ethanol (C 2 H 6 O) and formaldehyde (HCHO)) at 130 C. These gases are typical components of indoor toxic gas and biomarkers. The selectivity of the MLTPS gas sensor to 50 ppm of the abovementioned gases at 130 C is displayed in Fig.…”

“…[1][2][3][4][5] They are broadly applied in elds ranging from health monitoring and medical detection to safety. 3,[6][7][8] Among the currently available metal oxide semiconductors, SnO 2 , as a typical n-type semiconductor with a 3.6 eV band gap, has been extensively studied in the eld of gas sensors and applied to the detection of a number of different gases such as HCHO, CH 3 OH, NH 3 , C 2 H 6 O, CO, SO 2 , CH 4 and H 2 S. 6,[9][10][11][12][13][14] However, the practical applications of SnO 2 have been limited due to its low selectivity, high operating temperature and unsatisfactory sensing response. Recently, to overcome these limits, most efforts to optimize its performance have been based on composition modication, structure optimization and process improvement.…”

“…17 Xu et al decorated SnO 2 with bimetal PdAu, and exhibited dual selectivity for detecting formaldehyde and acetone. 6 However, composition modication faces challenges in terms of control of the component quantity and complicated synthesis processes; this adds to the cost of the materials. Moreover, because the sensing mechanism of SnO 2 is surfacecontrol type, a large number of researchers have made signicant efforts to develop novel structures to improve its gas sensing performance.…”