Sno2-reduced graphene oxide nanocomposite for ethanol sensing at room temperature

Abstract

Nanocomposites based on metal oxide semiconductors and reduced graphene oxide (RGO) have been proposed as gas sensors to respond at room temperature. In this work, we prepared SnO2-RGO nanocomposite by microwave-assisted hydrothermal (MAH) method in one-step. The combined characterization techniques including X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, field emission-scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS) and transmission electron microscopy (TEM) confirm the formation of SnO2-RGO nanocomposite, and the distribution of SnO2 nanoparticles on RGO surface. The gas sensing performance of SnO2-RGO was evaluated by ethanol exposure at room temperature (21 °C). The results of gas sensing performance reveal that SnO2-RGO sensor has a great response to ethanol at room temperature, with a response time of about 100 seconds for the highest concentration of the gas (1,500 ppm). Moreover, it was found that the sensor has a higher selectivity for ethanol than for methanol. It is considered that RGO plays an important role in the gas sensing response.