Au-loaded Zn2SnO4/SnO2/ZnO nanosheets for fast response and highly sensitive TEA gas sensors

Triethylamine (TEA), a poisonous and combustible gas, is extremely dangerous to both human health and the surrounding environment. Thus, it is essential to produce a gas sensor for rapid and accurate detection of TEA. In this study, hydrothermal and impregnation techniques were used to create Zn2SnO4/SnO2/ZnO (ZSO) nanosheets that were decorated with Au nanoparticles (Au NPs). The synthesized materials were characterized by XRD, SEM, TEM, and XPS. The results showed that the materials were hexagonal nanosheets with a side length of 600–800 nm and a thickness of about 100 nm. The as-synthesized materials were used with TEA gas sensors, and the effectiveness of their sensing was thoroughly assessed. The sensor's response with the best gas sensing performance can be as high as 116–100 ppm TEA, which is 12 times that of the material before modification. The sensor also showed improved long-term stability, greater selectivity, a quick response time of 1 s, and low detection limits of 0.5 ppm. An efficient synthesis method of Au NPs-loaded multi-heterojunction materials was provided, and the mechanism behind the sensing performance was thoroughly described. [Display omitted] •Au-Zn2SnO4/SnO2/ZnO nanosheets were prepared by hydrothermal/impregnation methods.•The sensor exhibited a low detection limit of 0.5 ppm to TEA.•The sensing properties depend on the heterojunctions, and modification of Au NPs.