▎ 摘　　要

Nitrogen-doped graphene quantum dots (N-GQDs) with a size of 2.5-8.5 nm are ultra-uniformly grown in situ on thermally reduced graphene oxide (rGO) and are different from those catalysts fabricated by adding pre-prepared GQDs artificially. N-GQD/rGO shows catalytic activity for the oxygen reduction reaction, which is comparable to that of the Pt/C catalyst, but with better durability and a higher tolerance to the methanol crossover effect. This method might extend the application of N-GQDs in electrocatalysis.