Common Characterization Methods of Graphenes

The scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy (RS), atomic force microscopy (AFM), X-ray diffractometer (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR) and other equipments, were used to characterize the surface morphology, layer number, defect condition and functional group of 3 groups of graphene powder samples prepared by oxidation graphite reduction method and physical method and 3 groups of graphene film samples prepared by chemical vapor deposition (CVD) method. Through the comparative analysis of the test results, it is found that the SEM is most applicative for surface morphology characterization of graphenes. The RS is good at layer number testing of graphene film samples, and AFM is more suitable for graphene powder samples. The RS analysis is the best method for the defect analysis in the graphenes compared with other methods, and through it the defect density can be calculated and the defect type can be determined. The type and content of the functional group in the graphenes can both be determined by XPS analysis which is an effective method for graphene functional group characterization.