Self-supporting oxygen reduction electrocatalysts made from a nitrogen-rich network polymer.

We report the design, synthesis, and evaluation of a new type of non-precious-metal catalyst made from network polymers. 2,6-Diaminopyridine was selected as a building-block monomer for the formation of a nitrogen-rich network polymer that forms self-supporting spherical backbone structures and contains a high density of metal-coordination sites. A Co-/Fe-coordinating pyrolyzed polymer exhibited a high specific oxygen reduction activity with onset and half-wave potentials of 0.87 and 0.76 V vs RHE, respectively, in neutral media. There was no crossover effect of organics on its activity. The power output of a microbial fuel cell equipped with this catalyst on its cathode was more than double the output with a commercial 20 wt % Pt/C catalyst.