MOF-derived In2O3/ZnO hollow porous nanotubes enable rapid low-temperature detection of TEA

Rational construction of In 2 O 3 /ZnO n-n heterojunction hollow hexagonal structure nanotubes via MOF template strategy. • In 2 O 3 /ZnO sensor exhibits an ultrafast response of 1 s to TEA at a low operating temperature of 90 °C. • Compared with the pristine In 2 O 3 sensor, the In 2 O 3 /ZnO composite exhibits a 3.08-fold higher response toward TEA, with a limit of detection of 1 ppm. • The superior gas-sensing performance originates from the unique porous hollow structure of In 2 O 3 /ZnO and the n-n heterojunction constructed at the interface, which provides a promising strategy for the rapid low-temperature detection of TEA. Metal-organic frameworks (MOFs) have designed frame structures and excellent catalytic properties, which can effectively address practical application challenges of triethylamine (TEA) gas sensors. In this study, a hollow porous nanotube composite of In 2 O 3 /ZnO was synthesized using a solvothermal method with MOFs serving as sacrificial templates, and it was then utilized for low-temperature rapid detection of TEA. This composite material, characterized by a unique porous hollow structure and n-n heterojunction, boasts a high specific surface area and numerous active sites, resulting in outstanding gas sensitivity performance at lower operating temperatures. At the optimal operating temperature of 90 °C, the In 2 O 3 /ZnO-2 sensor exhibits a rapid response (1 s) to 200 ppm TEA, and its response value of 34.3 is 3.08 times that of the original In 2 O 3 sensor. In addition, this sensor also exhibits excellent selectivity, reproducibility, and moisture resistance. This experiment provides an effective solution for the rapid detection of TEA at low temperatures. The In 2 O 3 /ZnO sensor exhibits a response value of 34.3 toward 200 ppm TEA at a low operating temperature of 90 °C, with a response time as low as 1 s, as well as excellent selectivity, repeatability and long-term stability. The enhanced depletion layer induced by the n-n heterojunction and the unique hollow hexagonal structure are considered to be the key factors responsible for the improved gas-sensing performance of the composite. Download: Download high-res image (112KB) Download: Download full-size image