Nanoporous Fe and Co Dually Doped Carbon Nanotube-Based Oxygen Electrocatalysts for Efficient Zinc–Air Batteries

The development of bifunctional electrocatalysts to overcome the slow kinetics of the oxygen reduction–evolution reaction (ORR/OER) remains a significant challenge. Therefore, combined with morphology control engineering and bimetallic doping strategies, Fe and Co bimetals are effectively doped into carbon nanotube-coated three-dimensional porous materials, and a cost-effective bifunctional oxygen-electrode material is successfully prepared. The synthesized Fe25–NZ8@Co500-CN catalysts show high electrocatalytic activity in both ORR (E1/2 = 0.85 V) and OER (ηj=10 = 350 mV). Furthermore, the zinc-air battery is assembled with the Fe25–NZ8@Co500-CN catalyst as the air electrode, which has an excellent power density of 183.65 mW cm–2, a specific capacity of 699.2 mA h gZn–1, and a long-term stability of 200 h. This newly synthesized bimetallic-doped catalyst offers a design option for oxygen electrocatalysts in zinc–air batteries.