A novel nitrogen-containing electrocatalyst for oxygen reduction reaction from blood protein pyrolysis

We report a new strategy to design carbon-based electrocatalysts containing nitrogen through the co-pyrolysis of blood protein and carbon black support. The results show that the nitrogen in electrocatalysts is primarily in the form of pyridinic- and pyrrolic-type nitrogen species. High-temperature pyrolysis processes can transfer a significant amount of pyridinic-N to pyrrolic-N. The electrocatalyst containing a higher amount of the pyrrolic-N configuration exhibits better electrocatalytic activity towards oxygen reduction reaction in terms of onset potential, half-wave potential, and limited current density. It is suggested that the pyrrolic-N configuration may be the electrocatalytically active site and may be responsible for the enhanced ORR performance in alkaline media. The carbon black support also plays an important role in the pyrolysis process, improving the ORR catalytic activity.