  Based on first principles density functional theory calculations we explored
energetics of oxygen reduction reaction over pristine and nitrogen-doped
graphene with different amounts of nitrogen doping. The process of oxygen
reduction requires one more step then same reaction catalyzed by metals.
Results of calculations evidence that for the case of light doped graphene
(about 4% of nitrogen) energy barrier for each step is lower than for the same
process on Pt surface. In contrast to the catalysis on metal surface the
maximal coverage of doped graphene is lower and depends on the corrugation of
graphene. Changes of the energy barriers caused by oxygen load and corrugation
are also discussed.
