Dispersion of chemically-modified graphene and its applications

J.T. Han, S.H. Kim, J.S. Kim, S.Y. Jeong, H.J. Jeong, G-W Lee
Korea Electrotechnology Research Institute, KR

Keywords: chemically-modified graphene, dispersion, conductivity


In this study, we present straightforward methods to produce large-area GO sheets with fewer defects on the basal plane and for addressing the problems associated with dispersing reduced GO nanosheets in organic solvents for applications. First, the large and less defective GO nanosheets were successfully produced by inducing shear stress in solution using a homogenizer. The shear-induced exfoliation process for preparing GO significantly influenced rGO formation, not only by introducing fewer structural defects on the basal plane but also by producing large-area rGO sheets with high qulity. The enhanced sheet resistance of the rGO thin film was found to be 2.2 kohm/sq at 80% transmittance. Second, a stable dispersion of rGO sheets in an organic solvent was achieved as a result of hydrophobic interactions between sp2 carbons in rGO surfaces and acac stabilizer ligands in the TiO2 precursor sol. Moreover, the conductivity of the rGO multilayer films was therefore enhanced, and the carrier mobility could be controlled by varying the quantity of TiO2 sol in the precursor solution.