Catalytic activities enhanced by abundant structural defects and balanced N distribution of N-doped graphene in oxygen reduction reaction

• Abundant structural defects on graphene enhance the ORR activity.
• Balanced N distribution on graphene could also improve the ORR activity.
• Structural defects and N distribution are adjusted by regulating temperature.
• NG-1000 shows notable ORR activities in both alkaline and acid media.

N-doped graphene (NG) is a promising candidate for oxygen reduction reaction (ORR) in the cathode of fuel cells. However, the catalytic activity of NG is lower than that of commercial Pt/C in alkaline and acidic media. In this study, NG samples were obtained using urea as N source. The structural defects and N distribution in the samples were adjusted by regulating the pyrolysis temperature. The new NG type exhibited remarkable catalytic activities for ORR in both alkaline and acidic media.