Promoting Electrocatalytic Oxygen Reduction in a Model Composite Using Selective Metal Ions

The oxygen reduction reaction (ORR) is critically important in energy converting systems, and the advancement of a catalyst that accelerates the process is vital. Here, an ORR electrocatalyst was developed by the stoichiometric addition of Co(II) ions to a model composite (FePH) and termed as gamma-CoFePH. The developed electrocatalyst shows a significant enhancement in ORR activity with improved E-onset and E-1/2 (3 mA cm(-2)) values, where E-1/2 is -0.29 V as compared to -0.60 V for FePH, drifting toward Pt/C and exhibits a limiting current density of -6.3 mA cm(-2) which exceeds the commercially available Pt/C. The gamma-CoFePH also displays superior resistance toward methanol poisoning and stability of over 40 000 s retaining 83.6% of the current density under alkaline medium.