▎ 摘 要
The mild oxidation of natural graphite was obtained via the modified Hummers method by employing an oxidation temperature of 20(circle)C and KMnO4 loading of 2 g, while the degree of mild oxidation was controlled by varying the oxidation time from 30 to 60, 90 or 120 min. The mild oxidation of graphite was demonstrated by X-ray diffraction (XRD), along with UV-vis spectroscopy, scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). Then, MOG (mildly-oxidized graphite) was grafted with aryldiazonium salts of sulfonic acid (ADS) to afford good water dispersion, followed by sonication exfoliation and centrifugation to isolate the few-layer-graphene (FLG). The FLG was characterized by transmission electron microscopy (TEM), atomic force microscopy (AFM) and Raman spectroscopy, and its sheet resistance (R-s), yield and water dispersion stability were also evaluated. The obtained FLG had low R-s (3 x 10(2) to 5.8 x 10(4) Omega square(-1)), high yield (19-85%), and good stability in water (79-86% after 4 week aging).