Guided Assembly of Graphene Oxide in Aqueous Solution

Graphene oxide is a chemically modified, hydrophilic form of graphene that can be processed in water to yield new carbon-based films, fibers, and folded particles.  The atomic thinness of GO along with its micron-scale lateral dimensions make it a flexible sheet-like colloid with an extreme aspect ratio.  Graphene oxide solutions have been observed to phase separate into ordered regions under shear when salt is introduced into the solution.  We interpret this assembly process as the formation of vorticity bands based on a log-rolling mechanism. Here, we investigate multiple processing parameters that have an effect on the formation of the ordered regions.  The characteristics of these regions have been found to be a function of GO concentration, salt valency and concentration and gap confinement; the control of these parameters allows for the manipulation of the characteristics of the regions of separated GO phase, a desirable ability in nanomanufacturing.