High-performance pyrolyzed iron corrole as a potential non-precious metal catalyst for PEMFCs

Abstract

This work demonstrates the performance of carbon black-supported pyrolyzed Fe–corrole (py-Fe–corrole/C) as a cathode catalyst for the oxygen reduction reaction (ORR) in PEMFCs. The ORR measurements reveal that the py-Fe–corrole/C exhibits good ORR activity, via the direct four-electron reduction pathway, in the reduction of O₂ to H₂O. The H₂–O₂ PEMFC produces high activity and good stability. The enhanced ORR activity is attributable to the network structure of poly-aromatic hydrocarbons, the quaternary (graphitic)-type nitrogen and the coordination structure of the py-Fe–corrole/C. Square wave voltammetry has been applied to the py-Fe–corrole/C to perform a redox reaction of Fe(II)/Fe(III) at 0.6 V. Finally, detailed in situ X-ray adsorption spectroscopy has been applied to determine the ORR mechanism of py-Fe–corrole/C.