High sensitive and low concentration detection of methanol by a gas sensor based on one-step synthesis α-Fe2O3 hollow spheres

Hematite (alpha-Fe2O3) hollow spheres were prepared by a one-step hydrothermal reaction without template and used to fabricate the gas sensors. Structure and morphology of the product were characterized by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The results indicated that the alpha-Fe2O3 hollow spheres were composed of nanoparticles with the diameter of 50-70 nm, and the average diameter of alpha-Fe2O3 hollow spheres was 250 nm. The sensor based on alpha-Fe2O3 hollow spheres exhibited excellent sensing performance to methanol at 280 degrees C, and the response can be reached at 25 when the concentration as low as 10 ppm. In addition, sensing mechanism of the sensor towards alpha-Fe2O3 hollow spheres was investigated. (C) 2016 Elsevier B.V. All rights reserved.