High-Performance MoO3 Nanosheets Gas Sensors for Triethylamine Detection: A Rapid Approach for Assessing Fish Freshness

Triethylamine (TEA) is an organic amine released by fish products during spoilage, and the concentration of TEA can be detected by sensors to determine the freshness of fish. However, current TEA sensors face issues such as low response, high detection limits, and high power consumption. In this paper, pure phase molybdenum trioxide nanosheets (MoO 3 Ns) with high-performance TEA detection were prepared by hydrothermal method. By adjusting the calcination temperatures, the sensor response was enhanced, and both the detection limit and power consumption were reduced due to chemical sensitization and reasonable interactions between the material surface and the target gas. Material characterization indicates that MoO 3 calcined at 400°C exhibits a lamellar morphology, high catalytic activity, and a crystal surface with abundant hydroxyl groups, adsorbed oxygen, and Mo 6+ . By adjusting different calcination temperatures, the response was improved and the detection limit and power consumption were reduced based on chemical sensitization and reasonable interaction between the material surface and the target gas. Material characterization indicates that MoO 3 calcined at 400°C exhibits a lamellar morphology, high catalytic activity crystal surface with abundant hydroxyl groups, adsorbed oxygen, and Mo 6+ , and has suitable specific surface area with wide pore size distribution. Gas sensitivity tests reveal that the MoO 3 -400 based sensor demonstrates excellent performance, including a high response (280/50 ppm), low detection limit (1 ppm), and low power consumption (235°C). Furthermore, the sensor exhibits outstanding cycling, long-term stability, and selectivity. Finally, the sensor's applicability was demonstrated by measuring TEA released by crucian carp to evaluate fish freshness. This paper introduces a novel method for rapidly assessing fish spoilage, providing a significant contribution to food safety.