A Gas Sensor With Fe2O3 Nanospheres Based on Trimethylamine Detection for the Rapid Assessment of Spoilage Degree in Fish

• Main Authors: Likun Liu, Shuang Fu, Xiao Lv, Liling Yue, Li Fan, Haitao Yu, Xiuli Gao, Wenbin Zhu, Wei Zhang, Xin Li, Wenquan Zhu
• Format: Article
• Language: English
• Published: Frontiers Media S.A. 2020-09-01
• Series: Frontiers in Bioengineering and Biotechnology
• Subjects: solvothermal method; nanoparticle; α-Fe2O3; trimethylamine gas sensing; fish spoilage
• Online Access: https://www.frontiersin.org/article/10.3389/fbioe.2020.567584/full

A spherical iron oxide precursor was prepared using a solvothermal method, and then treated thermally at 400°C to obtain α-Fe2O3 nanoparticles. The structures and morphology of the as-obtained products were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The results showed that the diameter of the α-Fe2O3 nanoparticles was approximately 500 nm. In addition, we formed the α-Fe2O3 nanoparticles into a thick film as a gas sensor and performed a gas sensing test. When the working temperature was set at 250°C, the α-Fe2O3 nanoparticle displayed very good selectivity and high sensitivity for trimethylamine (TMA). The minimum detection was as low as 1 ppm, and the response value for 100 ppm TMA gas was 27.8. Taken together, our findings illustrated that the α-Fe2O3 nanoparticles could be used as a gas-sensitive material to test the freshness of fish.