Structural Evolution of Graphene Oxide and Its Thermal Stability During High Temperature Sintering

The thermal reduction of graphene oxide (GO) was performed by a tube furnace at different temperatures, and its structure evolution was investigated in detail. The results showed that the oxygen-containing functional groups on the carbon plane surface of GO gradually decomposed as the temperature increase, and the reduced graphene oxide (rGO) powder was obtained at 800 °C. Then, rGO powder was sintered under 30 MPa at 1 800 °C using spark plasma sintering (SPS) and hot-pressing (HP) to evaluate its structural stability at high temperatures. The defect densities of rGO were reduced after high-temperature sintering. The edge flatness and sp 2 hybrid carbon plane structure were reconstructed effectively. These results demonstrate that the lamellar structure of rGO maintains the structural integrity during high-temperature sintering without obvious deterioration, which provides experimental and theoretical supports for GO reinforced ceramics.