Chemiresistive triethylamine detection based on novel titanium‐oxo clusters gas sensor and practical application in food spoilage monitoring

Abstract Traditional TiO 2 gas sensing materials face limitations such as difficult energy band adjustment and high operating temperatures. Titanium‐oxo clusters (TOCs), molecular analogs of TiO 2 , have shown promise in various applications but remain underexplored in practical applications of gas sensors. This study synthesized two classical TOCs, Ti 4 O 2 (O i Pr) 10 (1‐Nap) 2 (Ti 4 ) and [Ti 8 O 8 (OMc) 16 ]·2CH 3 CN (Ti 8 ), via solvothermal methods and evaluated their performances in detecting triethylamine (TEA) gas in the air for the first time. The Ti 4 and Ti 8 sensors exhibited high response values of 7.80 and 5.47, respectively, to 100 ppm TEA at optimal operating temperatures of 80 and 50 °C, with excellent selectivity. Response/recovery times were 25/91 s for Ti 4 and 137/230 s for Ti 8 . Both sensors demonstrated good repeatability and long‐term stability. The Ti 8 sensor, with its lower operating temperature and superior linear fitting, was used to monitor carp fish freshness, showcasing its practical application potential. Finally, the sensing mechanism is analyzed. This study pioneers the use of TOCs for TEA detection and food freshness monitoring, offering new avenues for chemiresistive gas sensors.