Electroreduction of O₂ to H₂O at Unusually Positive Potentials Catalyzed by the Simplest of the Cobalt Porphyrins

Simple cobalt porphine, adsorbed on graphite electrodes, catalyzes the direct reduction of O2 to H2O, while most other monomeric cobalt porphyrins do not. The surprising behavior of cobalt porphine suggests possible new strategies for the design of electrocatalysts for the reduction of O2 to H2O using structurally similar but more oxidation-resistant analogs.