Dealloying‐Derived Porous Spinel Oxide for Bifunctional Oxygen Electrocatalysis and Rechargeable Zinc‐Air Batteries: Promotion of Activity Via Hereditary Al‐Doping

Abstract The large‐scale fabrication of highly efficient and low‐cost bifunctional catalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is critical to the development of rechargeable zinc‐air batteries (ZABs). Herein, a scalable dealloying strategy was proposed to obtain hierarchically porous spinel‐type oxide with minor hereditary Al doping. Benefiting from the well‐structured porosity and native dopant, O‐np‐Ni 5 Co 10 (Al), namely Al−NiCo 2 O 4 , exhibited excellent electrocatalytic ORR and OER activities, giving a small potential gap of 0.71 V. The rechargeable ZAB with O‐np‐Ni 5 Co 10 (Al) as cathode catalyst delivered a high specific capacity of 757 mAh g −1 , a competitive peak power density of 142 mW cm −2 , and a long‐term discharge‐charge cycling stability. Furthermore, density functional theory calculations evidenced that appropriate Al doping into NiCo 2 O 4 could significantly reduce the Gibbs free energy difference to 1.71 eV. This work is expected to inspire the design of performance‐oriented bifunctional electrocatalysts for wider applications in renewable energy systems.