Nanoporous Carbon-Supported Fe/Co-N Electrocatalyst for Oxygen Reduction Reaction in PEM Fuel Cells

As a substitute for high-cost platinum based catalysts, nonprecious catalysts for the oxygen reduction reaction were synthesized by deposition of Fe/Co-N composite onto two different nanoporous carbon supports, Ketjen Black EC300J and EC600JD, using ethylenediamine as a nitrogen precursor. Rotating ring disk electrode measurements were used to investigate the ORR activity, and the results obtained from EC600JD based catalyst, showed improved onset and half-wave potentials and superior selectivity than that of the EC300J. Similarly, the catalyst showed good performance in the hydrogen-oxygen PEMFC, being able to produce 0.37 A/cm2 with a maximum power density of 0.44 W/cm2 at a cell voltage of 0.6 V. A fuel cell life test at a voltage of 0.40 V demonstrated promising stability up to 100 h. These results suggest that a higher pore volume and surface area of the carbon support could lead to higher nitrogen content, providing more active sites for ORR.