Triethylamine gas sensor based on Zn2SnO4 polyhedron decorated with Au nanoparticles and density functional theory investigation

The effective detection of toxic and harmful triethylamine (TEA) gases is of great significance for the living environment and personal safety. Therefore, it is necessary to develop a high-quality TEA sensor that can respond quickly and has high response and low detection limits. In this work, Au nanoparticles (NPs) were successfully loaded onto the surface of the Zn2SnO4 (ZSO) polyhedron by hydrothermal and subsequent impregnation methods. The formation of Schottky junctions between Au and ZSO and the sensitization effect of Au NPs can effectively improve the sensor's sensitivity to triethylamine. The gas characteristic test results show that the AuZSO2-based sensor exhibits the highest response value to TEA. Specifically, at a working temperature of 300°C, the response of the sensor based on AuZSO2 to 100 ppm TEA is as high as 193, which is more than 7 times that of ZSO. The detection limit is reduced from 0.5 ppm to 0.1 ppm. Moreover, the AuZSO2-based sensor exhibits excellent selectivity and stability. Meanwhile, the sensitivity mechanism of the sensor was further explained through density functional theory (DFT). The research provides a reference value for improving the performance and explaining the mechanism of TEA sensors.