The fabrication and triethylamine sensing performance of In-MIL-68 derived In2O3 with porous lacunaris structure

•In-MIL-68 derived porous lacunaris structure In2O3 for triethylamine sensor was synthesized by a simple method.•In2O3-500 sensor shows excellent sensing performance, the response of 32 when exposed to 100 ppb TEA at 120 °C.•Gas sensitivity mechanism about the improvement of gas sensitivity performance has been studied and discussed in this work. Gas sensors with high sensitivity, selectivity, stability, moisture resistance and reliable fabrication potency for detection of toxic and harmful gases have been now expected for many applications in the environment. Herein, a kind of triethylamine (TEA) gas sensors can quantitatively detect on ppb level gases is reported. The sensors were fabricated with porous lacunaris structure In2O3 derived from metal-organic frameworks In-MIL-68 by annealing at a suitable temperature 500 °C. It exhibited the highest response of 32 when exposed to 100 ppb TEA gas at the optimal operation temperature 120 °C, and the response and recovery time is 9 s and 36 s respectively. Furthermore, it also demonstrated outstanding selectivity, stability (without any change after 40 days) and moisture resistance (kept 86.2 % response at 90 % relative humidity). In addition, the good response linearity within a wide TEA concentration range of 0.1 ppm–5 ppm and lower detection limit are other advantages of the sensor. Considering these advantages, In-MIL-68 derived In2O3 sensor is a promising candidate for TEA detection. The gas sensing mechanism is also explored here.