Fabrication and ethanol-sensing properties of micro gas sensor based on electrospun SnO2 nanofibers

SnO2 nanofibers were obtained by electrospinning of a poly(vinyl alcohol) (PVA)/SnCl4·5H2O solution. A novel micro gas sensor based on the SnO2 nanofibers was successfully fabricated. The morphology and crystal structure of the fibers were analyzed by scanning electron microscope (SEM), transmission electron microscope (TEM) and X-ray diffraction (XRD), and the ethanol-sensing properties of the sensor were tested. The results showed that the SnO2 nanofibers with an average diameter of ∼100 nm could be directly deposited on a microhotplate by “near-field” electrospinning. The micro gas sensor exhibited large response, low detection limit, fast response/recovery and good reproducibility. The detection limit was <10 ppb and the response/recovery time towards 10 ppm ethanol was <14 s.