Fe-N-C electrocatalysts for oxygen reduction reaction synthesized by using aniline salt and Fe³⁺/H₂O₂catalytic system

Non-precious metal (NPM) catalysts are synthesized by polymerizing aniline salt using an aqueous Fe³⁺/H₂O₂coupled catalytic system on a carbon matrix with a porous creating agent. The sulfur containing compunds such as ammonium peroxydisulfate, are eliminated in this method resulting in a much simpler process. The catalysts' porous structures are enhanced with ammonium carbonate as a sacrificial material that yields voids when decomposed during the heat treatment at 900 °C in N₂atmosphere. Two catalysts Fe-N-C/Vu and Fe-N-C/KB (Vu = Vulcan and KB = Ketjen black) were synthesized and characterized. Their oxygen reduction reaction (ORR) activities were investigated using a rotating ring-disk electrode (RRDE) in both 0.1 M KOH and 0.1 M HClO₄. The catalysts show improved ORR activities close to that of Pt-based catalysts, low H₂O₂formation and also demonstrated a remarkable tolerance towards methanol oxidation.