Synthesis of mono layer graphene oxide from sonicated graphite flakes and their Hall effect measurements

Graphene, a single atom thick sheet is considered a key candidate for the future nanotechnology, due to its unique extraordinary properties. Researchers are trying to synthesize bulk graphene via chemical route from graphene oxide precursor. In the present work, we investigated a safe and efficient way of monolayer graphene oxide synthesis. To get a high degree of oxidation, we sonicated the graphite flakes before oxidation. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) results confirmed graphene oxide formation and high degree of oxidation. Raman spectroscopy and atomic force microscopy (AFM) results revealed a monolayer of graphene oxide (GO) flakes. The sheet like morphology of the GO flakes was further confirmed by scanning electron microscopy (SEM). The Hall effect measurements were performed on the GO film on a silica substrate to investigate its electrical properties. The results obtained, revealed that the GO film is perfectly insulating, having electrical resistivity up to 8.4 × 108 (Ω·cm) at room temperature.