The effect of tunable graphene oxide sheet size on the structures and catalytic properties of three-dimensional reduced graphene oxide sponge

Based on the selective precipitation of graphene oxide sheets (GOSs), large, medium and small GOSs would be narrowed and controlled by adjusting the time and speed of centrifugation. This size selection principle was used to investigate the influence of GOS size on dispersion, structure, and stacking behavior of GOSs. The structures and catalytic properties of three-dimensional reduced graphene oxide (3D rGO) sponge could also be controlled by the tunable GOS size. These differences due to the different GOS size were correlated to multiscale elemental and structural characteristics of GOSs, such as C/O ratio, the content of oxygen-containing groups on the GO edge, and Raman intensity ratio of D to G-bands of GO on the molecular scale. The relationship between GOS size and the structures and catalytic properties of 3D rGO sponge was established.