Formation of Large-Area Nitrogen-Doped Graphene Film Prepared from Simple Solution Casting of Edge-Selectively Functionalized Graphite and Its Electrocatalytic Activity

Abstract

"Pristine" graphite is edge-selectively functionalized with 4-aminobenzoic acid by a "direct" Friedel Crafts acylation reaction in a polyphosphoric acid/phosphorus pentoxide medium to produce 4-aminobenzoyl edge-functionalized graphite (EFG). The EFG is readily dispersible in N-methyl-2-pyrrolidone (NMP). Subsequent solution casting leads to the formation of large-area graphene film on a silicon wafer. The film shows sheet resistances of 60 and 200 Omega/sq, respectively, before and after heat treatment at 900 degrees C in an argon atmosphere. Upon the heat treatment, the EFG film becomes a N-doped graphene (N-graphene) film to display outstanding electrocatalytic activity for oxygen reduction reaction (ORR).