MoO3/CeO2 nanorods for TEA gas sensors: sensing performance, mechanism study, and application to detection of seafood freshness

MoO 3 nanorods, successfully modified with CeO 2 , were synthesized using the hydrothermal technique and subsequently utilized for gas detection. Various techniques were employed to test and analyze the MoO 3 /CeO 2 materials. Numerous characterizations have confirmed that the synthesized MoO 3 /CeO 2 possesses excellent properties. The synthesized MoO 3 nanorods demonstrated uniformity in size, with an approximate diameter of 146 nm. CeO 2 nanoparticles were distinctly visible on the surface of the MoO 3 nanorods. The MoO 3 /CeO 2 sensor demonstrated significantly enhanced sensing performance for triethylamine at 240 °C. Specifically, the MoO 3 /CeO 2 sensor exhibited a reactivity of 73.1 to 20 ppm of triethylamine, signifying an improvement of 3.5 times compared to the reactivity of the MoO 3 nanorods. The sensor based on MoO 3 /CeO 2 exhibited high selectivity, good repeatability, and a lower detection limit for TEA. The enhancement of the gas-sensing performance of the MoO 3 /CeO 2 sensor may have been attributed to the accelerated electron transfer facilitated by the heterojunction formed between MoO 3 and CeO 2 . Additionally, underlying sensing mechanism was investigated using Density Functional Theory (DFT) methodologies.