Synthesis and Gas Sensing Properties of ∝-Fe2O3 Microspheres Toward ppb-Level Aniline Detection

We successfully obtained ∝-Fe2O3 microspheres with a ca. 500 nm diameter through solvothermal method and subsequent annealing at 300 °C for 2 h in air. The composition and morphology of the samples were analyzed by FT-IR, XRD, SEM, TEM, TG and BET. The gas sensitivity measurements indicated that the sensor of ∝-Fe2O3 microspheres showed good selectivity and high response to aniline gas. This sensor showed a response to aniline gas as low as 0.01 ppm, and the response achieved 12.5 at 150 °C to 10 ppm aniline. The enhanced gas sensing properties were due to enough pore architectures of the sample. These results demonstrated that the samples have a good application prospect in preparation of high-performance gas sensors.