MOF-derived In2O3 microtubes as an effective sensing material for sub-ppm-level triethylamine detection

The development of triethylamine (TEA) gas sensors play an important role in industrial gas detection and environmental quality analysis. In this work, the TEA gas sensor was prepared porous In2O3 microtubes synthesized by hydrothermal treatment and annealing process. The morphological characterization displayed that the length of the porous In2O3 microtube was approximately 7∼9 μm and the diameter was around 0.8∼1.1 μm. Gas sensing measurements indicated that the sensor based on the porous In2O3 microtubes exhibited a superior response to 1 ppm TEA (Ra/Rg = 145) at 140 °C, short response time (5) and acceptable recovery time (20 s), good reversibility, excellent selectivity and the TEA detection limits as low as 100 ppb. The possible response mechanism is also discussed carefully through density functional theory (DFT) calculation, which illuminates that the porous In2O3 microtubes are expected to be potential candidates for TEA detection in practical application.