【摘 要】
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In this work,porous La1-xBaxFeO3 (x =0.01,0.02,0.03,0.04 and 0.05) microspheres of the orthorhombic perovskite phase were prepared by an envi-ronment-friendly o
【机 构】
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School of Material Science and Engineering,University of Jinan,Jinan 250022,China;Shandong Academy o
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In this work,porous La1-xBaxFeO3 (x =0.01,0.02,0.03,0.04 and 0.05) microspheres of the orthorhombic perovskite phase were prepared by an envi-ronment-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 inhib-ited 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 La1-xBaxFeO3 sensor exhibits a fairy high response to the ethanol gas.In par-ticular,the La1-xBaxFeO3 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,demon-strating the superiority as an ethanol sensing nanomaterial.More importantly,the optimum operating temperature of La0.98Ba0.02FeO3 is only 200 ℃,while that of the pure LaFeO3 is 260 ℃.The Ba-doped porous microspheres prepared are a high-performance sensing material capable of rapid and accurate detection of ethanol.
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