Impact of oxidation morphology on reduced graphene oxides upon thermal annealing

Thermal reduction of graphene oxide (GO) is an essential technique to produce low-cost and higher quality graphene-based materials and composites used today in a plethora of applications. However, despite a demonstrated efficiency of high-temperature annealing in reducing the oxygen content of GO, the impact of the morphology of the initially oxidized samples on the restored sp(2) graphene plane versus remaining sp(3) imperfections remains unclear and out-of-control. Here using classical molecular dynamics, we simulate the process of thermal reduction on several GO samples for a variety of initial conditions and elucidate how both the concentration of oxygen functional groups and their spatial distribution jeopardize the reduction process efficiency. Our simulations suggest thermal annealing strategies to further optimize the crystallinity of reduced GO, enhancing their transport properties and hence making the resulting composites even more performant for electronic applications.