Synthesis of Ba-doped porous LaFeO3 microspheres with perovskite structure for rapid detection of ethanol gas

In this work, porous La 1− x Ba x FeO 3 ( x = 0.01, 0.02, 0.03, 0.04 and 0.05) microspheres of the orthorhombic perovskite phase were prepared by an environment-friendly one-step hydrothermal method with a series of characterization of the six sensing nanomaterials. Characterization results show that their grain size is between 21.2 and 23.2 nm, and the grain growth is inhibited with the increase in Ba-doping concentration. The samples are all spherical with a diameter of about 10 μm, and the surface is very rough. By the gas sensing study of the samples, the results show that the La 1− x Ba x FeO 3 sensor exhibits a fairly high response to the ethanol gas. In particular, the La 1− x Ba x FeO 3 microspheres with a Ba-doping concentration of 2 mol% showed not only a significant improvement in sensitivity but also a rather rapid response recovery time compared to the undoped samples, demonstrating the superiority as an ethanol sensing nanomaterial. More importantly, the optimum operating temperature of La 0.98 Ba 0.02 FeO 3 is only 200 °C, while that of the pure LaFeO 3 is 260 °C. The Ba-doped porous microspheres prepared are a high-performance sensing material capable of rapid and accurate detection of ethanol. Graphic abstract