In this study, films of graphene oxide and chemically or thermally reduced graphene oxide were produced by a simple vacuum\nfiltration method and submitted to a thorough characterization by X-ray diffraction (XRD), Raman and infrared spectroscopies,\nfield-emission scanning electron microscopy, transmission electron microscopy, atomic force microscopy, confocal microscopy,\nand contact angle measurements. Graphene oxide (GO) was produced from graphite by the modified Hummers method and\nthereafter reduced with NaBH4 or by heating under argon in a tubular furnace. The films were produced from aqueous\nsolutions by vacuum filtration on a cellulose membrane. Graphite presents two characteristic XRD peaks corresponding to d =\n0 34 nm and d = 0 17 nm. After oxidation, only a peak at d = 0 84nm is found for powder GO, confirming the insertion of\noxygen groups with an increase in the interplanar distance of graphene nanoplatelets. However, for GO films, other unexpected\npeaks are observed at d = 0 63nm, d = 0 52nm, and d = 0 48nm. After reduction, both chemical and thermal, the peak at\n0.84 nm disappears, while those corresponding to interplanar distances of 0.63 nm, 0.52 nm, and 0.48nm are still present. The\nother characterizations confirm the production and chemical composition of GO and reduced GO films. The results indicate the\ncombination of crystalline regions with different interplanar distances, suggesting the ordering of graphene/graphene oxide\nintercalated sheets.
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