High Mass and Specific Activity for Ammonia Electro‐oxidation through Optimization of Dispersion Degree and Particle Size of Pt‐Ir Nanoparticles over N‐Doped Reductive Graphene Oxide

Abstract Platinum and iridium co‐supported on N‐doped reductive graphene oxide (N‐rGO) electrocatalysts (Pt−Ir/N‐rGO) were synthesized and investigated for ammonia electro‐oxidation reaction (AOR) in alkaline media. Pt and Ir particles were deposited over the N‐rGO substrate through a potentiodynamic electrodeposition method. The deposition parameters, lower potential limit ( E L ) and scan rate, play a vital role on the dispersion degree and particle size of Pt−Ir bimetallic nanoparticles over N‐rGO. Additionally, the comparable current densities and a better poisoning inhibition are obtained compared to the commercial Pt (20 wt%)/C indicating that a synergistic effect among Pt, Ir and N‐rGO substrate is existing in favour on the electrocatalytic activity. The N‐rGO substrate with more active sites, higher excellent electrochemical activity and well dispersion for Pt and Ir particles anchoring is a suitable substrate for AOR and would be extended to other catalytic reactions.