N-doping of graphene: toward long-term corrosion protection of Cu†
Despite the extraordinary impermeability of graphene, graphene fails to prevent the oxidation of Cu substrates under long-term air exposure owing to their high conductivity. Previous investigations showed that N-doped graphene could modulate the electrical properties of graphene while there has been no experimental example to investigate the protective performance of N-doped graphene to date. Here we demonstrate the synthesis and characterization of N-doped graphene with large-area atomic layers, and then evaluate its protective properties by both short- (electrochemical tests) and long-term (air exposure) corrosion tests. The results show that both short- and long-term corrosion are inhibited because incorporating nitrogen in graphene can decrease the conductivity of graphene and thus prevent the electron transport between Cu/N-doped graphene interfaces. Our finding provides a new protection method of graphene and will promote the basic research and applications of graphene.