Few-layer jellyfish-like graphene nanoflakes: functionalization, N-doping, and application in catalysis and carbon dot synthesis

The present study is devoted to a unique type of graphene-based material, few-layer graphene nanoflakes (GNFs). GNFs are of less than 50 nm in size, while their bent edges make them look like jellyfish. Oxidation of GNFs results in a core-shell structure consisted of a few-layer graphene core decorated at the edges by oxygen containing functional groups, mostly carboxyls and phenols. The similar structure is observed for graphene quantum dots. This material demonstrates the promising properties for application in electrochemistry especially after N-doping. At the same time the great number of edge carbon atoms allows decorating GNFs with metal nanoparticle, which is convenient for the catalyst preparation. Such nanoparticles can be also a starting material for the synthesis of carbon quantum dots with the few-layer graphene core. The synthesis, functionalization, and N-doping of GNFs will be presented and discussed along with the results of the electrochemical capacitance measurements and catalytic tests