Toward N-Doped Graphene via Solvothermal Synthesis

Theoretical studies predicted that doping graphene with nitrogen can tailor its electronic properties and chemical reactivity. However, experimental investigations are still limited because of the lack of synthesis techniques that can deliver a reasonable quantity. We develop here a novel method for one-pot direct synthesis of N-doped graphene via the reaction of tetrachloromethane with lithium nitride under mild conditions, which renders fabrication in gram scale. The distinct electronic structure perturbation induced by the incorporation of nitrogen in the graphene network is observed for the first time by scanning tunnelling microscopy. The nitrogen content varies in the range of 4.5-16.4%, which allows further modulation of the properties. The enhanced catalytic activity is demonstrated in a fuel cell cathode oxygen reduction reaction with respect to pure graphene and commercial carbon black XC-72. The resulting N-doped materials are expected to broaden the already widely explored potential applications for graphene.