Preparation of Yb-doped SnO2 hollow nanofibers with an enhanced ethanol-gas sensing performance by electrospinning

Pure and Yb-doped (0.5 wt%, 1.0 wt%, 1.5 wt%) SnO2 hollow nanofibers were synthesized by single capillary electrospinning followed by calcination at 600 degrees C for 2 h. The structural, morphological and elemental composition were investigated by X-ray diffraction (XRD), energy-dispersive X-ray detector (EDX), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer-Emmett-Teller(BET) and X-ray photoelectron spectroscopy (XPS). The results showed that the hollow nanofiberswere composed of SnO2 nanoparticles and Yb3+ ions were successfully doped into the SnO2 lattice. Most importantly, the sensors based on 1.0 wt% Yb-doped SnO2 hollow nanofibers exhibited perfect sensing performance toward ethanol with excellent selectivity, high response (170 for 500 ppm) and fast response-recovery capability (7 s for adsorption and 8 s for desorption) compared to pure SnO2 hollow nanofibers for the same ethanol concentration at 340 degrees C. The results obtained in this study indicate that 1.0 wt% Yb-doped SnO2 hollow nanofibers are potential candidates for fabricating effective ethanol sensors. The growth mechanism and the ethanol sensing mechanism of the hollow nanofibers were discussed in this paper. (C) 2015 Elsevier B.V. All rights reserved.