SnO2 NSs synthesized by hydrothermal method for Cl2 sensing

Abstract

Three-dimensional flower-shaped tin dioxide nanosheets (SnO2 NSs) are prepared by magnetic stirring, hydrothermal reaction and ice bath rapid cooling using tin dichloride dihydrate as raw material. The same raw materials and preparation process are used to prepare the tin oxide nanoparticles (SnO2 NPs) by natural cooling. The SEM characterization results show that SnO2 NPs is about 50 nm, and it is composed of the irregular aggregation of nanoparticles. The SnO2 NSs formed by rapid cooling show a three-dimensional flower-like morphology with well dispersion and interconnection. The reliable analysis of the growth mechanism of SnO2 NSs is supplied through the literature investigation and material characterization results. Compared with SnO2 NPs, the higher specific surface area of SnO2 NSs makes it have stronger gas sensitive response value and selectivity to chlorine gas (Cl2). The gas response of the SnO2 NSs sensor is 223 to 5 ppm Cl2 at 160 °C, and the detection limit is 0.0981 ppb by linear fitting of detection results at different concentrations. The SnO2 NSs sensor maintains good stability with a fluctuation range of 11% in the relative humidity lower than 60% and exhibits excellent selectivity to Cl2. A series of results demonstrate that SnO2 NSs has large latent capacity as a gas sensor material for monitoring Cl2. The possible mechanism of the preeminent performance of the SnO2 NSs for Cl2 detection is also deduced in detail.