A low-cost method for preliminary separation of reduced graphene oxide nanosheets

Reduced graphene oxide (RGO) nanosheets were produced by chemical reduction of exfoliated graphite oxide. Atomic force microscopy (AFM) images show that the obtained RGO nanosheets vary greatly in lateral-dimensional sizes, ranging from less than 100  100 nm to more than 2000  2000 nm. In order to separate these nanosheets, one simple and low-cost method mainly based on magnetic-stirring and centrifugation treatments was proposed. Preliminary statistical analysis of RGO nanosheets, based on AFM images, shows that the dot-like RGO nanosheets (with lateral dimensions less than 100  100 nm) and leaf-like RGO nanosheets (with lateral dimensions more than 500  500 nm) were effectively separated by this simple method.