Oxygen Reduction Electrocatalysis Using N-Doped Graphene Quantum-Dots

First-principles investigations of the electrocatalytic activity toward the four-electron oxygen reduction-reaction in N-doped graphene quantum dots reveal that pyridinic and graphitic nitrogen are the most active sites with overpotentials of 0.55 and 0.79–0.90 V, respectively. This agrees with experimental findings. Our calculations account for van der Waals interactions, solvent effects, and describe the electrochemistry using standard hydrogen electrode model. The results show correlations between OH*, OOH*, and O* binding energies that impose a lower limit on the oxygen reduction overpotential.