A MOF-derived porous In2O3 flower-like hierarchical architecture sensor: near room-temperature preparation and fast trimethylamine sensing performance

Abstract

We have successfully prepared a metal–organic-framework (MOF) derived In₂O₃ flower-like hierarchical architecture sensor using a near room-temperature template-free strategy and a subsequent accurate annealing process. The In₂O₃ flower-like hierarchical architecture sensor exhibits good sensitivity to trimethylamine. The fabricated sensor has a relatively low working temperature of 140 °C, a response of 35.2 for 20 ppm trimethylamine, a response time as fast as 2 s, and good selectivity and stability. In addition, the sensor exhibits good conductivity. The sensor's enhanced gas sensing performance can be attributed to the synergistic effect of its unique flower-like hierarchical architecture, porous hierarchical morphology and abundant oxygen vacancies. Furthermore, the possible growth mechanism and the gas sensing mechanism are also discussed in detail.