▎ 摘　　要

An effective and scalable exfoliation route has been developed to prepare high quality pristine graphene sheets. A remarkable yield of 55 wt % was achieved at a high solvent concentration of 20 mg/mL, with the application of only 1 h ultrasonication in total. The exfoliation process was achieved by synergistic effect of intercalation, self-assemblage, and further expansion. The successful exfoliation was proved by means of X-ray diffraction (XRD) patterns, Raman spectra, transmission electron microscopy (TEM), and scanning electron microscopy (SEM). Furthermore, preparation of large-area and ultrathin pristine graphene films were demonstrated by a facile, rapid, and scalable electrophoretic deposition approach. The pristine graphene sheets which are extremely sensitive to the applied electric field were arrayed in strict order to form the high-quality graphene films. The resultant graphene films exhibit a high electrical conductivity of similar to 1 X 10(5) S/m. Raman spectroscopy analysis reflected bilayer morphology of the graphene film. The simple and rapid processing route and the high transparency and conductivity of the graphene films suggest their potential applications in electrical and optical fields.