Wireless portable detection of hazardous triethylamine vapor at near-room temperature via ZnO nanoflowers functionalized with titanium-oxo cluster.

Triethylamine (TEA) is a widely used industrial solvent, yet its high volatility and toxicity pose significant risks to occupational safety and environmental air quality, with a recommended workplace exposure limit of 10 ppm. Real-time, low-temperature monitoring of TEA remains challenging for metal oxide semiconductor sensors, which require elevated operating temperatures. Herein, we report a ZnO nanoflower sensor functionalized with a classical titanium-oxo cluster [Ti8O8(OMc)16]·2CH3CN (Ti8) that enables sensitive and selective TEA detection at near-room temperature. The ZnO/5% Ti8 sensor achieves a response (Ra/Rg) of 5.29 toward 100 ppm TEA, a 4.3-fold enhancement over pristine ZnO, with a low detection limit of 0.39 ppm. The sensor exhibits a response to TEA at least 3 times higher than that to common interfering vapors and retains 90% of its initial response over 30 days. The enhanced performance is attributed to the Ti8-induced increase in chemisorbed oxygen on the ZnO surface, which provides more active sites for TEA oxidation. As a proof-of-concept demonstration for portable TEA detection, the sensor was integrated into a compact Bluetooth-enabled device capable of wirelessly transmitting response data to a smartphone. This work provides a material design strategy for low-power, portable detection of hazardous TEA for workplace and environmental safety.