Study of oxygen-containing groups in a series of graphite oxides: Physical and chemical characterization

Some graphite oxides with different degrees of oxidation have been prepared by using a modified Staudenmaier method. The oxidation process has been studied by using different techniques: elementary analysis, gas adsorption, X-ray diffraction, FT-IR, XPS and 13C-NMR. The influence of the oxidation degree on the appearance and evolution of new chemical groups in the samples has been analyzed. The oxidation process produces a development of porosity, especially microporosity. FT-IR, XPS and 13C-NMR are complementary techniques, which confirm the existence of hydroxyl, carbonyl, ether, epoxy, and peroxy groups in the more oxidized samples. These surface groups may play an important role in the acid-base bifunctional catalysis.