PBA-Derived Ternary FeCoNi Alloy Supported on N-Doped Porous Carbon as a Bifunctional Catalyst for Zn-Air Batteries

One of the challenges preventing rechargeable Zn-air batteries (ZABs) from being used in larger commercial applications is their slow oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). Low-cost transition metal carbon-based materials are generally considered to be the most promising materials to replace precious metal catalysts to improve the OER and ORR performance. However, practical application of these materials is hampered by poor activity and stability. By optimization of the preparation technology and composition of the material, the catalytic activity and durability of the catalyst can be improved. Herein, through iterative coprecipitation and pyrolysis methods, FeCoNi alloy nanoparticles coated with graphitized carbon nanotubes (FeCoNi-N-CS) were constructed on activated carbon. The FeCoNi-N-CS exhibits impressive bifunctional electrocatalytic activity in alkaline media with a half-wave potential (E-1/2) of 871 mV for the ORR, an overpotential of 334 mV at the current density of 10 mA cm(-2) (E-j=10) for the OER. Furthermore, when this catalyst is applied in ZAB, a greater specific capacity of 791 mAh g(Zn)(-1) and long-term cycling stability compared to commercialized Pt/C + RuO2 can be achieved.