In₂O₃ Hierarchical Structures of One-Dimensional Electrospun Fibers with in Situ Growth of Octahedron-like Particles with Superior Sensitivity for Triethylamine at Near Room Temperature

Abstract

A one-step single-spinneret electrospinning method is used to prepare tunable In2O3 hierarchical structures of one-dimensional electrospun fibers with in situ growth of octahedron-like particles, and various typical microstructures can be obtained by accurately adjusting the parameter of calcination time. A gas-sensing performance test indicates that hierarchical In2O3 sensors not only have a good gas-sensing response value of about 11.2 for 50 ppm triethylamine (TEA) at 25 °C, but they also have the highest response value (87.8 for 50 ppm TEA) at an optimal working temperature (40 °C) compared with other In2O3 microstructures in the present work. Significantly, sensors based on In2O3 hierarchical structures have excellent gas selectivity and stability, which can be applied for monitoring of freshness of shrimps, demonstrating a practical application of sensors in the chemical and food industries. The synergistic effect of an accessible surface structure, multiple reaction sites, and unique electron transmissions results in enhanced gas-sensing performances. This study offers a promising method for the construction of various inorganic oxide gas sensors with unique hierarchical microstructures for efficiently detecting TEA at near room temperature.