Highly responsive detection of triethylamine gas based on Gd-doped MoO3 nanorod sensors: an experimental and first-principles study

Triethylamine (TEA) is widely used in industrial production, but it poses a threat to human health. Therefore, it is crucial to develop highly sensitive sensors for TEA. In this paper, Gd-doped MoO₃ nanorod structures with different molar ratios were prepared via a step hydrothermal route by taking advantage of the excellent properties of rare earth elements. After comprehensively characterize, it was confirmed that Gd was successfully doped into the MoO₃ lattice. The sensor based on 3 mol% Gd-doped MoO₃ exhibited a larger specific surface area and a higher amount of surface-adsorbed oxygen compared to sensors with other doping ratios. The sensor with this optimal doping ratio has a gas sensing response of about 65.8 for 10 ppm TEA at 150 ℃, which is six times higher than that of the pure MoO₃ nanorods, with a response time of only 16 s. In addition, the sensor exhibits excellent selectivity, good reproducibility, and excellent long-term stability. Finally, density-functional theory (DFT) calculations indicate that the gadolinium-doped MoO₃ material significantly improved the sensing performance for TEA. This study provides a valuable reference for the development of metal-semiconductor (MOS) sensors for the detection of TEA.