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A series of N-doped carbon materials (NCs) were synthesized by using biomass citric acid and dicyandiamide as renewable raw materials via a facile one-step pyrolysis method. The characterization of microstructural features shows that the NCs samples are composed of few-layered graphene-like nanoflakes with controlled in situ N doping, which is attributed to the confined pyrolysis of citric acid within the interlayers of the dicyandiamide-derived g-C3N4with high nitrogen contents.Evidently,the pore volumes of the NCs increased with the increasing content of dicyandiamide in the pre-cursor.Among these samples,the NCs nanoflakes prepared with the citric acid/dicyandiamide mass ratio of 1:6,NC-6, show the highest N content of ~6.2 at%, in which pyri-dinic and graphitic N groups are predominant.Compared to the commercial Pt/C catalyst, the as-prepared NC-6 exhi-bits a small negative shift of ~66 mV at the half-wave potential, demonstrating excellent electrocatalytic activity in the oxygen reduction reaction. Moreover, NC-6 also shows better long-term stability and resistance to methanol crossover compared to Pt/C. The efficient and stable per-formance are attributed to the graphene-like microstructure and high content of pyridinic and graphitic doped nitrogen in the sample, which creates more active sites as well as facilitating charge transfer due to the close four-electron reaction pathway. The superior electrocatalytic activity coupled with the facile synthetic method presents a new pathway to cost-effective electrocatalysts for practical fuel cells or metal–air batteries.