Low-concentration and high-efficiency detection of triethylamine (TEA) based on Sn-doped WO3 gas sensors

Recently, the monitoring of TEA has garnered significant attention, particularly concerning food safety, which could potentially lead to health risks. However, current studies on the detection of TEA using tungsten trioxide (WO 3 ) materials are suboptimal and require the exploration of effective WO 3 -based sensitive materials. This work employs a one-step solvothermal method to synthesize Sn-doped WO 3 materials with varying ratios and analyzes their selectivity and sensitivity to gases. The physicochemical properties of materials were characterized using multiple techniques including XRD, SEM, XPS, BET and Raman spectroscopy. The high response to TEA gas is successfully achieved by adjusting the doping amount of Sn 4+ (∼12 wt%). Qualitative analyses indicate that 10 wt% Sn-WO 3 exhibits superior response to TEA in all samples, showcasing a response of 94.5 at 175 °C for 100 ppm TEA, which is 5.7 times higher than that of WO 3 . Also, the related mechanisms were studied in detail. The low-intensity ratio of the (002) facet, small particle size, large specific surface area, and high concentration of oxygen vacancy defects resulting from Sn 4+ doping play pivotal roles in enhancing the response to TEA. It is expected that this work will contribute to advancements in WO 3 -based materials in the field of gas sensing.