Coupling effect between cobalt oxides and carbon for oxygen reduction reaction.

Same selectivity hides different pathways: The same apparent 4-electron process for the oxygen-reduction-reaction hides different pathways over carbon-supported cobalt oxide catalysts depending on the potential. At low overpotentials, the ORR intermediate HO(2) (-) preferably disproportionates to oxygen, whereas at high overpotentials the disproportionation and reduction reaction occur in parallel.