LAUSR

Abstract Transition metal phosphates electrocatalysts are promising candidates either for oxygen evolution reaction (OER) or oxygen reduction reaction (ORR) in water splitting or metal-air batteries due to their low cost and high electrocatalytic activity, however, it is still a great challenge to discover bifunctional electrocatalysts with a high electrocatalytic performance for OER and ORR. In this work, using a facile self-template method, the optimal 2D amorphous N-doped CoFe-phosphate displays superior electrocatalytic performances toward both ORR and OER, which exhibits a lower overpotential of 313 mV at 10 mA cm−2 (Ej=10) for OER and a high half-wave potential of 0.74 V(E1/2) for ORR and a small potential gap ΔE (ΔE = Ej=10 − E1/2) of 0.80 V in 1.0 M KOH electrolyte. Furthermore, this bifunctional electrocatalyst was applied in Zn–air battery with a high power density (74.6 mW cm−2), specific capacity (750 mAhgZn−1), and long-term stability (over 30 h at 10 mA cm−2). Our study provided a new synthetic strategy to design and fabricate new 2D heteroatom-doped electrocatalytic materials with mesoporous structured for energy conversion applications, above all, in rechargeable Zn–air battery.