Excellent acetone sensing properties of Sm-doped α-Fe2O3

Pure and 3 wt% Sm-doped alpha-Fe2O3 nanotubes are prepared via a typical electrospinning technology and calcination procedure. The characteristic and morphology of the synthesized nanotubes are investigated by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM). Compared with pure alpha-Fe2O3 nanotubes, 3 wt% Sm-doped alpha-Fe2O3 nanotubes display enhanced gas-sensing properties. The response of 3 wt% Sm-doped alpha-Fe2O3 nanotubes is 33-50 ppm acetone, which is 13 times larger than that of pure alpha-Fe2O3 nanotubes. The lowest detection limit of acetone is 500 ppb to which the response is 2.3 at the optimum operating temperature of 240 degrees C. The response and recovery times are about 6 and 11 s to 50 ppm acetone, respectively. In addition, 3 wt% Sm-doped alpha-Fe2O3 nanotubes exhibit good selectivity and long term stability. (C) 2014 Elsevier B.V. All rights reserved.