NH3 gas sensing properties of a gas sensor based on fluorinated graphene oxide

A gas sensor is fabricated by dropping fluorinated graphene oxide (f-GO) onto SiO2/Si wafers patterned with Pt electrodes. X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and Raman spectroscopy are used to characterize the graphene oxide (GO) after fluorination. In addition, resistance measurement is used to investigate the ammonia (NH3) gas sensing behavior and resistivity of the f-GO based gas sensor. The f-GO shows that the fluorine content on the GO surface increases with increasing fluorine partial pressure without any significant structural changes. The gas sensor fabricated using f-GO shows an approximately 7% change in the resistive response, whereas the non-treated GO does not exhibit any sensing ability to NH3 gas. This change in the response is attributed to the lower Fermi level of GO and the increased number of holes in the GO after fluorination, which is helpful for effectively attracting NH3 gas. The improvement indicates that the fluorination of GO can provide a novel modification method for GO-based NH3 gas sensor. (C) 2015 Elsevier B.V. All rights reserved.