Synthesis, characterization and ethanol vapor sensing performance of SnO2/Graphene composite film

High performing sensor consisting of SnO₂/Gn nanocomposite was fabricated using a novel one-step in-situ sonochemical method. The reducing properties of SnCl₂ was used to reduce graphite oxide (GO) so that SnCl₂ could be transformed to SnO₂ on the basal plane of graphene. The combined characterizations including X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier Transformed Infra-Red spectroscopic data (FTIR) indicated the successful formation of SnO₂/Gn composites. Current-voltage (I-V) characteristics of the gas sensor showed ideal ohmic behavior having low resistance. To demonstrate the product on sensing application, gas sensors were fabricated using SnO₂/Gn composites and used in detecting ethanol vapor at room temperature (27°C).The results indicate that the SnO₂/Gn composite exhibits a considerably high sensing performance of 17.54% response at 150 ppm ethanol vapor, rapid response and reproducibility. Furthermore, the performance of the gas sensor based on SnO₂/Gn is very stable for a long period of time under normal operating conditions. Therefore, it is suggested that SnO₂/Gn can be considered as an excellent sensing material which also has a potential for wider range of applications on sensors.