rGO/SnO2 nanocomposite based sensor for ethanol detection under low temperature

In this study, series of rGO/SnO2 nanocomposites were synthesized with hydrothermal method by mixing graphene oxide (GO) solution and pre-prepared SnO2 quantum dot solution. The phase structure and morphology of the as-obtained rGO/SnO2 nanocomposites were analyzed by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV–vis absorption spectrums, Raman spectroscopy, field emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM) technique. The detailed investigation of gas-sensing properties of rGO/SnO2 nanocomposites-based sensors exhibited that the gas response of SnO2-based sensors to ethanol gas increased with the addition of GO, especially when the GO dosage reached 3.3 wt%, which revealed the highest response value of 48.34–50 ppm ethanol gas at 120 oC. Besides, it also displayed an excellent selectivity, good repeatability and long-time stability. The mechanism of rGO functionalized SnO2 and enhanced ethanol gas sensing property at relative low temperature was proposed.