Design of narrow bandgap Fe2O3/MoO3 heterostructure for boosting triethylamine sensing performance

To achieve the rapid and real-time detection of triethylamine (TEA) gas, this study synthesized a gas sensor based on heterostructures of Fe2O3/MoO3 using a hydrothermal method. Fe2O3/MoO3 composites with a narrow bandgap (1.1 eV) were successfully synthesized by constructing heterostructures. The rapid and efficient detection of triethylamine was achieved at 220 ºC. The response and response/recovery times of the Fe2O3/MoO3 sensor with 50 × 10−6 triethylamine were 132 s and 5 s/10 s, respectively. The Fe2O3/MoO3 sensor maintained a good response to triethylamine gas, even at 80% relative humidity. The sensing mechanism of the Fe2O3/MoO3 sensor can be described in terms of adsorption energy and electronic behavior of the sensing layer using density functional theory (DFT). The results are consistent with the excellent selectivity and rapid response/recovery of the Fe2O3/MoO3 gas sensor for triethylamine. Therefore, the construction of heterostructures to facilitate electron transmission is an effective strategy to achieve rapid detection of triethylamine and is worthy of further exploration and investigation.