A comparison of single and double Co sites incorporated in N-doped graphene for the oxygen reduction reaction

Metal and nitrogen co-doped carbons (M-N/Cs) are promising alternatives to platinum-based catalysts for the oxygen reduction reaction (ORR). Here, density functional theory calculations used compare ORR activity of Co single double sites embedded in N-doped carbon. Two different models a site investigated, one which two stacked on top each other has atoms next graphene sheet. For both it is found that can proceed via dissociative mechanism splits ?OOH intermediate into ?O ?OH, but only sheet does result significant deviation from scaling relations. The adsorption energies intermediates investigated using implicit explicit solvent models, showing some variation results. In particular, addition water same side catalyst as stabilisation due hydrogen bonding, while an molecule adsorbed opposite atom have effect change coordination affects splitting d orbitals.