Ethanol sensors based on graphene/tin oxide

Tin oxide powders were prepared by chemical deposition and reduced graphene oxide (rGO) was prepared by oxidation-reduction method. Their structures were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). Different mass ratio of rGO were doped into tin oxide powders, and the mixed powders were then coated onto the ceramic tube as thick-film gas sensors. Sensing properties of different concentration of ethanol were tested by CGS-8 gas sensing analysis system. The sensing properties of rGO-doped sensors have improved a lot during relatively low temperature. In addition, the recovery performance has been shortened from more than 450 s to nearly 20 s at 110mA heating current.