Reduced graphene oxide/ZnO nanocomposite for application in chemical gas sensors

Coupling of graphene-based materials with metal oxide nanostructures is an effective way to obtain composites with improved gas sensing properties. In this work, we prepared a hybrid structure based on graphene oxide (GO) and ZnO nanostructures. The morphological, compositional and structural analyses of the composite material have been investigated using scanning electron microscopy, X-ray diffraction spectroscopy, energy dispersive X-ray analysis and Raman spectroscopy. The gas sensing properties of the obtained structure have been studied towards nitrogen dioxide, hydrogen and methane at relatively low (about 200 degrees C) operating temperatures. It has been demonstrated that the reduced graphene oxide (RGO)/ZnO composites exhibit 40-50\% better response to NO2 and H-2 compared to pure ZnO sensors. The obtained results show that the functionalization of the nanostructured ZnO with the RGO sheets is a promising strategy to develop chemical gas sensors with improved gas sensing properties.