High-performance transparent conductive films using rheologically derived reduced graphene oxide.

In this work, we produced large-area graphene oxide (GO) sheets with fewer defects on the basal plane by application of shear stress in solution to obtain high-quality reduced graphene oxide (RGO) sheets without the need for post-annealing processes. This is described as rheologically derived RGO. The large-area GO sheets were generated using a homogenizer in aqueous solution, which induced slippage of the GO in the in-plane direction during the exfoliation process, in contrast with the conventional sonication method. The effects of chemical reduction under mild conditions demonstrated that the formation of structural defects during the exfoliation process affected the RGO properties. In the Raman spectra, the I(D)/I(G) ratio of the homogenized RGO (HRGO) increased more than that of the sonicated RGO (SRGO) due to the large number of ordered six-fold rings on the basal plane. The enhanced sheet resistance of the HRGO thin film was found to be 2.2 kΩ/sq at 80% transmittance. The effective exfoliation method has great potential for application to high-performance RGO-transparent conducting films.